阅读说明：本技术 一种反应型功能聚酯母粒及其制备方法 (Reactive functional polyester master batch and preparation method thereof ) 是由 吉鹏 王华平 王朝生 徐毅明 徐虎明 谢伟 于 2021-09-23 设计创作，主要内容包括：本发明公开了一种反应型功能聚酯母粒及其制备方法,所述反应型功能聚酯母粒的分子链由二元酸与二元醇聚合链段、羟基封端的改性共聚组分链段构成,同时组分上还含有纳米无机成核剂；所述羟基封端的改性共聚组分为含4～14个碳原子、以-CH-(2)CH-(2)-、-CH-(2)OCH-(2)-和-CH-(2)OOCH-(2)-中的一种或多种为重复单元,同时以羟基封端的脂肪族二元醇中的一种或多种；其中,反应型功能聚酯母粒中改性共聚组分质量分数为30～60%；二元酸与二元醇的摩尔比为1:1.1～2.0。本发明工艺简单,通过引入两种改性组分共同作用解决了功能组分的高比例共聚有效性的问题以及母粒可结晶满足使用要求的问题,成本低廉,极具应用前景。(The invention discloses a reactive functional polyester master batch and a preparation method thereof, wherein the molecular chain of the reactive functional polyester master batch consists of a diacid and diol polymerization chain segment and a hydroxyl-terminated modified copolymerization component chain segment, and simultaneously, the components also contain a nano inorganic nucleating agent; the hydroxyl-terminated modified copolymerization component contains 4-14 carbon atoms and is-CH 2 CH 2 ‑、‑CH 2 OCH 2 -and-CH 2 OOCH 2 -one or more of repeating units, while one or more of aliphatic diols are terminated with hydroxyl groups; wherein the mass fraction of the modified copolymerization component in the reactive functional polyester master batch is 30-60%; the molar ratio of the dibasic acid to the dihydric alcohol is1: 1.1-2.0. The invention has simple process, solves the problem of high proportion copolymerization effectiveness of functional components and the problem that master batches can be crystallized to meet the use requirement by introducing the combined action of two modified components, has low cost and has wide application prospect.)

1. A reactive functional polyester master batch is characterized in that: the molecular chain of the reactive functional polyester master batch is composed of a diacid and dihydric alcohol polymerization chain segment and a hydroxyl-terminated modified copolymerization component chain segment, and meanwhile, the components also contain a nano inorganic nucleating agent;

the hydroxyl-terminated modified copolymerization component contains 4-14 carbon atoms and is-CH₂CH₂-、-CH₂OCH₂-and-CH₂OOCH₂-one or more of repeating units, while one or more of aliphatic diols are terminated with hydroxyl groups;

wherein the mass fraction of the modified copolymerization component in the reactive functional polyester master batch is 30-60%;

the molar ratio of the dibasic acid to the dihydric alcohol is 1: 1.1-2.0.

2. The reactive functional polyester masterbatch of claim 1, wherein: the particle size of the nano inorganic nucleating agent is 50-200 nm, and the addition amount of the nano inorganic nucleating agent is 0.01-0.1% of the mass fraction of the hydroxyl-terminated modified copolymerization component.

3. The reactive functional polyester masterbatch according to claim 1 or 2, wherein: the dibasic acid is one or more of terephthalic acid, succinic acid, adipic acid, suberic acid, sebacic acid and furandicarboxylic acid;

the dihydric alcohol is one or more of ethylene glycol, diethylene glycol, propylene glycol, butanediol, pentanediol, hexanediol, heptanediol, octanediol, nonanediol and decanediol.

4. The reactive functional polyester masterbatch of claim 3, wherein: the nano inorganic nucleating agent comprises inert inorganic powder or inorganic powder with catalytic reactivity.

5. The preparation method of the reactive functional polyester masterbatch according to any one of claims 1 to 4, wherein the preparation method comprises the following steps: and (2) carrying out esterification reaction on dibasic acid and dihydric alcohol, introducing a hydroxyl-terminated modified copolymerization component and a nano inorganic nucleating agent after the esterification reaction is finished, and carrying out pre-polycondensation reaction and final polycondensation reaction to obtain the reactive functional polyester master batch.

6. The method for preparing the reactive functional polyester masterbatch according to claim 5, wherein the method comprises the following steps: specifically, the method comprises the following steps of,

mixing and pulping dibasic acid, dihydric alcohol and a titanium composite catalyst to prepare slurry;

carrying out esterification reaction on the slurry;

preparing a hydroxyl-terminated modified copolymerization component and a nano inorganic nucleating agent into slurry;

adding the slurry, the heat stabilizer and the antioxidant into an esterification reaction product, and then carrying out a pre-polycondensation reaction and a final polycondensation reaction to obtain a reactive functional polyester master batch;

the titanium-based composite catalyst is prepared by compounding a titanium-silicon composite catalyst and a cobalt-based catalyst, and the titanium-silicon composite catalyst is prepared by loading a titanium-based catalyst on a silicon-based catalyst;

the titanium catalyst is tetrabutyl titanate or metatitanic acid, the silicon catalyst is silicon dioxide, and the cobalt catalyst is cobalt acetate.

7. The method for preparing the reactive functional polyester masterbatch according to claim 6, wherein the method comprises the following steps: the addition amount of the hydroxyl-terminated modified copolymerization component is that the mass ratio of the dibasic acid to the dibasic alcohol esterification product is 3:7 to 6:4, the addition amount of the titanium composite catalyst is 20-200 ppm of the mass of the dibasic acid, and the molar ratio of the titanium catalyst, the silicon catalyst and the cobalt catalyst in the titanium composite catalyst is 1 (0.1-10) to (0.1-10);

the addition amount of the heat stabilizer is 0.001-0.02% of the mass of the dibasic acid, and the addition amount of the antioxidant is 0.001-0.03% of the mass of the dibasic acid.

8. The method for preparing the reactive functional polyester masterbatch according to claim 6, wherein the method comprises the following steps: the esterification reaction is carried out at the temperature of 200-260 ℃, under the pressure of 20-80 KPa, for 2-4 h, and at the stirring speed of 5-20 rpm; the intrinsic viscosity of the esterification reaction product is 0.10-0.25 dL/g.

9. The method for preparing the reactive functional polyester masterbatch according to claim 6, wherein the method comprises the following steps: the particle size of the nano inorganic nucleating agent is 50-200 nm, and the addition amount of the nano inorganic nucleating agent is 0.01-0.1% of the mass fraction of the hydroxyl-terminated modified copolymerization component;

when the addition amount of the modified copolymerization component is that the mass ratio of the dibasic acid to the glycol esterification product is 3: 7-5: 5, the nano inorganic nucleating agent is selected to be inert inorganic powder comprising one or more of barium sulfate and calcium carbonate;

when the addition amount of the modified copolymerization component is that the mass ratio of the dibasic acid to the glycol esterification product is 5: 5-6: 4, the nano inorganic nucleating agent is selected from inorganic powder with ester exchange catalytic activity, and the nano inorganic nucleating agent comprises zinc oxide.

10. The method for preparing the reactive functional polyester masterbatch according to claim 6, wherein the method comprises the following steps: the temperature of the pre-polycondensation reaction is 220-270 ℃, the pressure is 0.5-1.0 KPa, the time is 0.5-2.5 h, and the stirring speed is 5-15 rpm;

the temperature of the final polycondensation reaction is 220-270 ℃, the pressure is 0-200 Pa, the time is 1.0-3.0 h, and the stirring speed is 5-10 rpm.

Technical Field

The invention belongs to the technical field of polyester preparation, and particularly relates to a reactive functional polyester master batch and a preparation method thereof.

Background

Polyester is a generic name of a polymer obtained by polycondensation of a polyhydric alcohol and a polybasic acid, mainly referring to polyethylene terephthalate (PET), and conventionally including linear thermoplastic resins such as polybutylene terephthalate (PBT) and polyarylate, and is a polymer having excellent performance and wide application, and has been widely used in the fields of fibers, plastics, films, and the like. Along with the requirement of diversification of fiber products, the development of novel polyester fiber materials is more and more urgent, and the development directions of new polyester and fiber products mainly comprise copolymerization modification, blending modification and surface coating finishing. The method for realizing the functionalization of the polyester and the fiber by adding the functional master batch has the advantages of good flexibility and lasting functionality, and simultaneously can adjust the blending ratio in time according to the needs of products, thereby being the most mainstream development direction of the functional new products at present.

The master batch is prepared by dispersing and mixing a plurality of components including organic functional components, inorganic functional components and polymers under the shearing action of a screw in a screw blending mode, extruding, cooling by water and granulating. The master batch processed and formed based on the physical method improves the differentiation and functionalization levels of the polyester fiber to a certain extent. With the continuous upgrade of the polyester fiber industry, higher requirements are put forward on the technology of the master batch. When the waste polyester bottle chips are recycled and reused for spinning, the dyeing property of the waste polyester bottle chips needs to be improved, and the fibers obtained by spinning are expected to have the effect of cationic dyeability by adding novel functional master batches, so that the competitiveness of products is improved, and the unification of environmental protection and high added value is realized.

Chinese patent CN107652422B discloses a method for preparing dyeable polyester of regenerated cationic dye by alcoholysis of waste polyester, which comprises the following steps: 1) pretreating waste polyester; 2) alcoholysis of waste polyester; 3) regulating the quality of the esterified substance, and adding m-phthalic acid-5-sodium sulfonate and polyethylene glycol as comonomers; 4) preparing polycondensation and slicing; the final regenerated cationic dyeable polyester has the intrinsic viscosity of 0.55-0.65 dl/g, the melting point of 220-230 ℃, the content of diglycol of 5.5 +/-0.3 percent and the chroma b value of less than 8. The regenerated cationic dyeable polyester prepared by the method can be used for preparing cationic dyeable polyester filaments and staple fibers, and realizes high-valued recycling of waste polyester.

However, from the practical application, in order to realize that the cation of the regenerated polyester fiber can be dyed, the regenerated polyester is subjected to alcoholysis and then is copolymerized with the sulfonate component, the whole process is extremely complex, meanwhile, a plurality of side reactions are very easy to occur in the alcoholysis and repolymerization processes, and especially, a great amount of excessive diol is needed in the alcoholysis process, and self-polycondensation is easy to occur to form a byproduct.

In view of the above problems, the polyester fiber industry has been concerned with developing copolyester masterbatches, such as cationic copolyester masterbatches, to achieve cationic dyeing of polyester fibers including recycled polyester fibers.

Chinese patent CN109456469A discloses a copolymerization type high-fluidity cationic polyester master batch matrix material and a preparation method thereof, wherein a dibasic acid I, a dibasic acid II and a dihydric alcohol I are uniformly mixed and then subjected to esterification reaction, and after the esterification reaction is finished, a high-fluidity branched structure modifier is introduced to perform pre-polycondensation reaction and final polycondensation reaction to obtain the copolymerization type high-fluidity cationic polyester master batch matrix material, wherein the high-fluidity branched structure modifier is an esterified substance which is prepared by the reaction of a branched structure acid or acid anhydride and the dihydric alcohol II and is terminated by hydroxyl. The melt index of the prepared product is 8-15 g/10min, and the viscosity is reduced by less than or equal to 0.02dL/g in the melt processing process.

The Chinese invention patent CN109180923A discloses a high-fluidity stain-resistant easily-dyed polyester master batch and a preparation method thereof, wherein the preparation method comprises the following steps: uniformly mixing dibasic acid I, dibasic acid II (sodium m-phthalate-5-sulfonate) and dihydric alcohol I, carrying out esterification reaction, introducing high-fluidity stain-resistant modifier after the reaction is finished, carrying out pre-polycondensation reaction and final polycondensation reaction to obtain the high-fluidity stain-resistant easily-contaminated polyesterThe master batch and the high-fluidity stain-resistant modifier are prepared by the reaction of acid or anhydride with a branched structure and dihydric alcohol II which is terminated by hydroxyl and is-CF₂CF₂O-is a repeating unit, has a polymerization degree of 1 to 5, and is terminated with a hydroxyl group. The prepared high-fluidity stain-resistant easily-dyed polyester master batch has the melt index of 8-15 g/10min, the viscosity reduction in the melt processing process is less than or equal to 0.02dL/g, and the surface energy<20J/cm². The preparation method of the invention has simple process.

The Chinese invention patent CN109456468A discloses a copolymer type high-fluidity hydrophilic easy-dyeing polyester master batch matrix material and a preparation method thereof, wherein the preparation method comprises the following steps: uniformly mixing dibasic acid I, m-phthalic acid-5-sodium sulfonate and dihydric alcohol I, then carrying out esterification reaction, introducing a high-fluidity hydrophilic modifier after the esterification reaction is finished, carrying out pre-polycondensation reaction and final polycondensation reaction to obtain a copolymer type high-fluidity hydrophilic easily-dyed polyester master batch base material, wherein the melt index of the prepared high-fluidity hydrophilic easily-dyed polyester master batch base material is 8-15 g/10min, the viscosity is reduced to be less than or equal to 0.02dL/g in the melt processing process, the contact angle between the surface and water is less than or equal to 30 degrees, the saturated water absorption rate is more than or equal to 150 percent, and when the addition amount in the polyester is 4-10 wt%, the dye uptake of the polyester fiber after being subjected to normal pressure boiling dyeing by a cationic dye is 94-98 percent. The method is simple and easy to implement, and the prepared polyester master batch matrix material has good flowing property, hydrophilic property and dyeing property.

The method for preparing the functional master batch by adopting the copolymerization method is an important method, but the problem that the master batch is dried and does not generate bonding before use is solved for solving the problems of effective copolymerization of a high-proportion modified component and crystallization capacity reduction of the high-proportion copolymerized polyester master batch of the modified component due to high randomness.

CN 103910981B discloses a branched chain type degradable hydrophilic polyester master batch and a preparation method thereof, wherein pyromellitic dianhydride reacts with lactic acid to prepare a branched chain monomer, then the branched chain monomer is subjected to a first esterification reaction with terephthalic acid and ethylene glycol, then polyol is added in a second pre-polycondensation process to carry out copolycondensation, and finally polycondensation is carried out to prepare the branched chain type degradable hydrophilic polyester. Although the branched chain type structure modification component is introduced in the polyester synthesis stage, the flow property of the polyester master batch is improved to a certain extent, the introduced branched chain type structure modification component is prepared by reacting pyromellitic anhydride and lactic acid at a molar ratio of 1:4 at 110-140 ℃ for 3-5h without a catalyst, because of the steric hindrance effect of pyromellitic anhydride, the temperature of the esterification reaction of hydroxyl on pyromellitic anhydride and lactic acid is higher than the temperature of the esterification reaction of lactic acid, the esterification reaction of general lactic acid is above 180 ℃, and catalyst conditions are also needed, so that the branched chain type structure modification component disclosed by the patent has more unreacted monomers, especially the stability of unreacted lactic acid is poor, the stability of the master batch is greatly influenced and the viscosity drop is large, and the fluidity is general. Meanwhile, the polyol introduced in the second-step prepolycondensation process in the above patent cannot be introduced into the molecular chain in an esterified form, and since the product in this stage is terminated with a hydroxyl group, the esterification reaction with the polyol cannot be carried out.

CN 106519201B discloses a preparation method of high-fluidity hydrophilic copolyester, which comprises the steps of mixing a modified component Tween and dihydric alcohol according to a certain mass ratio, pulping, adding Tween and an esterified substance when the esterification stage of the polyester is completed, completing the ester exchange process at a lower temperature by the Tween and the esterified substance, and preparing the high-fluidity hydrophilic copolyester through polycondensation after the ester exchange reaction is completed. Although the fluidity of the polyester master batch is improved to a certain extent, the introduced branched Tween is difficult to participate in the polyester copolymerization process due to the steric hindrance effect and the relatively high molecular weight, and meanwhile, part of the branched Tween is grafted into a polyester molecular chain to play a role in blocking, so that the molecular weight cannot be increased continuously.

Therefore, it is necessary to solve the problem of the master batch formed by copolymerization of a copolymerized polyester master batch while achieving effective copolymerization of a modified component at a high ratio, which is problematic in that the master batch is poor in crystallization ability due to a decrease in regularity and causes stickiness during drying.

Disclosure of Invention

This section is for the purpose of summarizing some aspects of embodiments of the invention and to briefly introduce some preferred embodiments. In this section, as well as in the abstract and the title of the invention of this application, simplifications or omissions may be made to avoid obscuring the purpose of the section, the abstract and the title, and such simplifications or omissions are not intended to limit the scope of the invention.

The present invention has been made keeping in mind the above and/or other problems occurring in the prior art.

One of the purposes of the invention is to provide a reactive functional polyester master batch, which solves the problem of high proportion copolymerization effectiveness of functional components and the problem that master batch can be crystallized to meet the use requirement by introducing two modification components under the combined action, has low cost and has great application prospect.

In order to solve the technical problems, the invention provides the following technical scheme: a reaction type functional polyester master batch, the molecular chain of the reaction type functional polyester master batch is composed of a diacid and diol polymerization chain segment and a hydroxyl-terminated modified copolymerization component chain segment, and meanwhile, the components also contain a nano inorganic nucleating agent;

the hydroxyl-terminated modified copolymerization component contains 4-14 carbon atoms and is-CH₂CH₂-、-CH₂OCH₂-and-CH₂OOCH₂-one or more of repeating units, while one or more of aliphatic diols are terminated with hydroxyl groups;

wherein the mass fraction of the modified copolymerization component in the reactive functional polyester master batch is 30-60%;

the molar ratio of the dibasic acid to the dihydric alcohol is 1: 1.1-2.0.

As a preferred scheme of the reactive functional polyester master batch, the reactive functional polyester master batch comprises the following components in percentage by weight: the particle size of the nano inorganic nucleating agent is 50-200 nm, and the addition amount of the nano inorganic nucleating agent is 0.01-0.1% of the mass fraction of the hydroxyl-terminated modified copolymerization component.

As a preferred scheme of the reactive functional polyester master batch, the reactive functional polyester master batch comprises the following components in percentage by weight: the dibasic acid is one or more of terephthalic acid, succinic acid, adipic acid, suberic acid, sebacic acid and furandicarboxylic acid;

the dihydric alcohol is one or more of ethylene glycol, diethylene glycol, propylene glycol, butanediol, pentanediol, hexanediol, heptanediol, octanediol, nonanediol and decanediol.

As a preferred scheme of the reactive functional polyester master batch, the reactive functional polyester master batch comprises the following components in percentage by weight: the nano inorganic nucleating agent comprises inert inorganic powder or inorganic powder with catalytic reactivity.

The invention also aims to provide a preparation method of the reactive functional polyester master batch, which comprises the steps of carrying out esterification reaction on dibasic acid and dihydric alcohol, introducing a hydroxyl-terminated modified copolymerization component and a nano inorganic nucleating agent after the esterification reaction is finished, and carrying out pre-polycondensation reaction and final polycondensation reaction to obtain the reactive functional polyester master batch.

As a preferred scheme of the preparation method of the reactive functional polyester master batch, the method comprises the following steps: specifically, the method comprises the following steps of,

mixing and pulping dibasic acid, dihydric alcohol and a titanium composite catalyst to prepare slurry;

carrying out esterification reaction on the slurry;

preparing a hydroxyl-terminated modified copolymerization component and a nano inorganic nucleating agent into slurry;

adding the slurry, the heat stabilizer and the antioxidant into an esterification reaction product, and then carrying out a pre-polycondensation reaction and a final polycondensation reaction to obtain a reactive functional polyester master batch;

the titanium-based composite catalyst is prepared by compounding a titanium-silicon composite catalyst and a cobalt-based catalyst, and the titanium-silicon composite catalyst is prepared by loading a titanium-based catalyst on a silicon-based catalyst;

the titanium catalyst is tetrabutyl titanate or metatitanic acid, the silicon catalyst is silicon dioxide, and the cobalt catalyst is cobalt acetate.

As a preferred scheme of the preparation method of the reactive functional polyester master batch, the method comprises the following steps: the addition amount of the hydroxyl-terminated modified copolymerization component is that the mass ratio of the dibasic acid to the dibasic alcohol esterification product is 3:7 to 6:4, the addition amount of the titanium composite catalyst is 20-200 ppm of the mass of the dibasic acid, and the molar ratio of the titanium catalyst, the silicon catalyst and the cobalt catalyst in the titanium composite catalyst is 1: 0.1-10;

the addition amount of the heat stabilizer is 0.001-0.02% of the mass of the dibasic acid, and the addition amount of the antioxidant is 0.001-0.03% of the mass of the dibasic acid.

As a preferred scheme of the preparation method of the reactive functional polyester master batch, the method comprises the following steps: the esterification reaction is carried out at the temperature of 200-260 ℃, under the pressure of 20-80 KPa, for 2-4 h, and at the stirring speed of 5-20 rpm; the intrinsic viscosity of the esterification reaction product is 0.10-0.25 dL/g.

As a preferred scheme of the preparation method of the reactive functional polyester master batch, the method comprises the following steps: the particle size of the nano inorganic nucleating agent is 50-200 nm, and the addition amount of the nano inorganic nucleating agent is 0.01-0.1% of the mass fraction of the hydroxyl-terminated modified copolymerization component;

when the addition amount of the modified copolymerization component is that the mass ratio of the dibasic acid to the glycol esterification product is 3: 7-5: 5, the nano inorganic nucleating agent is selected to be inert inorganic powder and comprises more than one of barium sulfate, calcium carbonate and the like;

when the addition amount of the modified copolymerization component is that the mass ratio of the dibasic acid to the glycol esterification product is 5: 5-6: 4, the nano inorganic nucleating agent is selected from inorganic powder with ester exchange catalytic activity, and the nano inorganic nucleating agent comprises zinc oxide.

As a preferred scheme of the preparation method of the reactive functional polyester master batch, the method comprises the following steps: the temperature of the pre-polycondensation reaction is 220-270 ℃, the pressure is 0.5-1.0 KPa, the time is 0.5-2.5 h, and the stirring speed is 5-15 rpm;

the temperature of the final polycondensation reaction is 220-270 ℃, the pressure is 0-200 Pa, the time is 1.0-3.0 h, and the stirring speed is 5-10 rpm.

Compared with the prior art, the invention has the following beneficial effects:

the preparation method of the reactive functional polyester master batch has simple process, solves the problem of high proportion copolymerization effectiveness of the functional components and the problem that the master batch can be crystallized to meet the use requirement by introducing the combined action of the two modification components, has low cost and has wide application prospect;

the reactive functional polyester master batch can selectively copolymerize functional components according to the application requirements of the master batch in fibers, can effectively improve the hand feeling and the dyeing property of polyester fibers by the copolymerization components including functional groups or chain segments containing ether bonds, sulfonate and the like, and has good application prospect.

Detailed Description

In order to make the aforementioned objects, features and advantages of the present invention more comprehensible, specific embodiments thereof are described in detail below with reference to examples of the specification.

In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention, but the present invention may be practiced in other ways than those specifically described and will be readily apparent to those of ordinary skill in the art without departing from the spirit of the present invention, and therefore the present invention is not limited to the specific embodiments disclosed below.

Furthermore, reference herein to "one embodiment" or "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one implementation of the invention. The appearances of the phrase "in one embodiment" in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments.

Aiming at solving the problems of the prior art that the master batch formed by the effective copolymerization and the copolymerization of the modified components in high proportion has poor crystallization capability and causes adhesion in drying and the like, the invention provides a reactive functional polyester master batch, the molecular chain of which is composed of a dibasic acid and dihydric alcohol polymerization chain segment and a modified copolymerization component chain segment, and the components also contain a nano inorganic nucleating agent;

the hydroxyl-terminated modified copolymerization component contains 4-14 carbon atoms and is-CH₂CH₂-、-CH₂OCH₂-and-CH₂OOCH₂-one or more of aliphatic diols in which the repeating units are simultaneously terminated with hydroxyl groups;

the mass fraction of the modified copolymerization component in the reactive functional polyester master batch is 30-60%, the content of the free unreacted copolymerization modified component is less than 0.5%, the cooling crystallization temperature of the reactive functional polyester master batch is 100-200 ℃, and the semicrystallization time t_1/2= 2-10 min, crystallization enthalpy 10-40J/g, crystallinity 10-40%, and thermal decomposition temperature (temperature corresponding to 5% mass loss) 350-400 ℃;

the number average molecular weight of the reactive functional polyester master batch is 10000-40000 g/mol, the intrinsic viscosity is 0.45-0.85 dL/g, and the melt index is 5-30 g/10 min. The reactive functional polyester master batch realizes high-proportion copolymerization of the modified components and simultaneously introduces the inorganic nucleating agent, on one hand, the copolymerization reaction can be promoted when the modified components are added in high proportion, on the other hand, the heterogeneous nucleation effect is realized, the crystallization performance of the functional polyester master batch can be improved, and the bonding can not occur in the drying and dehumidifying process before the spinning use.

As a preferred technical scheme:

the reaction type functional polyester master batch is characterized in that the dibasic acid is more than one of terephthalic acid, isophthalic acid, succinic acid, adipic acid, suberic acid, sebacic acid and furandicarboxylic acid;

the reactive functional polyester master batch is characterized in that the dihydric alcohol is more than one of ethylene glycol, diethylene glycol, propylene glycol, butanediol, pentanediol, hexanediol, heptanediol, octanediol, nonanediol and decanediol;

the hydroxyl-terminated modified copolymerization component contains 4-14 carbon atoms and is represented by-CH₂CH₂-、-CH₂OCH₂-and-CH₂OOCH₂-one or more of aliphatic diols in which the repeating units are simultaneously terminated with hydroxyl groups;

the nano inorganic nucleating agent is divided into inert inorganic powder and inorganic powder with catalytic reactivity, and the selection category is determined according to the addition amount of the modified copolymerization component.

The invention also provides a method for preparing the reactive functional polyester master batch, which comprises the steps of carrying out esterification reaction on dibasic acid and dihydric alcohol, introducing a hydroxyl-terminated modification component and a nano inorganic nucleating agent after the esterification reaction is finished, and carrying out pre-polycondensation reaction and final polycondensation reaction to obtain the reactive functional polyester master batch;

the molar ratio of the dibasic acid to the dibasic alcohol is 1: 1.1-2.0, and the hydroxyl-terminated modified copolymerization component contains 4-14 carbon atoms and is represented by-CH₂CH₂-、-CH₂OCH₂-and-CH₂OOCH₂-one or more ofThe repeating units are simultaneously one or more of aliphatic diols terminated with hydroxyl groups.

The size of the nano inorganic nucleating agent is 50-200 nm. The addition amount is 0.01-0.1% of the mass fraction of the modified copolymerization component; when the addition amount of the modified copolymerization component is that the mass ratio of the dibasic acid to the glycol esterification product is 3: 7-5: 5, the nano inorganic nucleating agent is selected to be inert inorganic powder and comprises more than one of barium sulfate, calcium carbonate and the like; when the addition amount of the modified copolymerization component is that the mass ratio of the dibasic acid to the glycol esterification product is 5: 5-6: 4, the nano inorganic nucleating agent is selected from inorganic powder with ester exchange catalytic activity, and the nano inorganic nucleating agent comprises zinc oxide and the like.

The method comprises the following specific steps:

(1) preparation of esterified slurry

Mixing and pulping dibasic acid, dihydric alcohol and a titanium composite catalyst to prepare slurry, wherein the titanium composite catalyst is prepared by compounding a titanium-silicon composite catalyst and a cobalt catalyst, and the titanium-silicon composite catalyst is prepared by loading a titanium catalyst on a silicon catalyst;

the invention adopts the titanium composite catalyst, the composite catalyst is selected in consideration of ensuring the catalytic effect and improving the final product, and other catalysts except the titanium-silicon-cobalt composite catalyst can also be selected, but the side reaction is increased and the color of the product is poor, so that the complex catalyst can realize higher catalytic activity and improve the color of the product;

the specific preparation method of the titanium composite catalyst comprises the following steps:

the titanium series composite catalyst is made of TiO₂-SiO₂Mixing the composite catalyst and cobalt catalyst in a certain proportion, adding into a polymerization system, wherein the TiO is obtained by adopting a sol-gel method₂-SiO₂The composite catalyst method comprises the following steps: adding proper amount of tetraethoxysilane, ethanol, distilled water and nitric acid into a three-neck flask in sequence, uniformly mixing, placing the three-neck flask on a magnetic stirrer for heating and refluxing, setting the heating temperature to be 65 ℃, the stirring speed to be 820r/min, refluxing for 2h, and adding 40.0g of tetrabutyl titanate into the three-neck flask after the tetraethoxysilane is completely hydrolyzedStirring for 20min to mix with reactant, slowly adding appropriate amount of distilled water at a certain speed by using a constant pressure burette, refluxing for 2h at 65 ℃ after dropwise adding is finished, aging for 12h at room temperature after gel is formed, drying for 12h at 110 ℃ in a blast drying oven, removing water and ethanol solvent in a reaction system, grinding dried solid in a mortar, putting ground powder into a muffle furnace, setting the baking temperature to be 500 ℃, starting timing after the temperature reaches the set temperature, baking for 3h, taking out the baked matter after baking is finished, naturally cooling, and finally obtaining TiO₂-SiO₂A composite catalyst;

(2) esterification reaction

Carrying out esterification reaction on the esterified slurry;

(3) preparation of modified copolymerization component slurry

Preparing a hydroxyl-terminated modified copolymerization component and a nano inorganic nucleating agent into slurry;

(4) polycondensation reaction

Adding the modified copolymerization component slurry, the heat stabilizer and the antioxidant into the esterification reaction product, and then carrying out pre-polycondensation reaction and final polycondensation reaction to obtain the reactive functional polyester master batch.

In the above method, the dibasic acid is one or more of terephthalic acid, isophthalic acid, sodium 5-sulfoisophthalate and furandicarboxylic acid, the dibasic alcohol is one or more of ethylene glycol, propylene glycol, butylene glycol, pentanediol, hexanediol, heptanediol, octanediol, nonanediol and decanediol, the titanium-based catalyst is tetrabutyl titanate or metatitanic acid, the silicon-based catalyst is silica, the cobalt-based catalyst is cobalt acetate, the heat stabilizer is one or more of trimethyl phosphate, alkyl diester phosphate and tris (nonylphenyl) phosphite, and the antioxidant is one or more of antioxidant 1010, antioxidant 168 and antioxidant 616.

According to the method, in the step (1), the molar ratio of the dibasic acid to the dihydric alcohol is 1: 1.1-2.0, the stirring speed of mixing and pulping is 5-25 rpm, and the time is 0.5-1.0 h;

the addition amount of the titanium-based composite catalyst is 20-200 ppm of the weight of the dibasic acid I, and the molar ratio of the titanium-based catalyst, the silicon-based catalyst and the cobalt-based catalyst in the titanium-based composite catalyst is 1: 0.1-10.

The invention can realize the uniform dispersion in the system by mixing the dibasic acid, the dihydric alcohol and other auxiliary agents in the slurry preparation stage, and ensure that the subsequent esterification reaction is uniformly and stably participated in. At the moment, only the viscosity of the system is low in the material mixing stage, and the mixing process of the materials can be realized without overhigh stirring speed or overlong stirring time, so that the stirring speed of mixing and beating is controlled to be 5-25 rpm for 0.5-1.0 h, the stirring speed and time of mixing and beating can be reduced in adaptability but are not overhigh, and the effective mixing of the materials cannot be realized by overlow stirring speed and overlow stirring time.

The reaction between the dibasic acid and the dihydric alcohol belongs to the organic chemical reaction of alcohol acid, excessive dihydric alcohol in a certain range can promote the reaction to be carried out in the positive direction, and the molar ratio of the dibasic acid to the dihydric alcohol is controlled to be 1: 1.1-2.0.

The addition amount of the titanium composite catalyst can be changed within a proper range but is not too high, the catalyst effect is reduced due to the excessively low addition amount of the catalyst, the reaction time is prolonged, and the efficiency is reduced; too high a catalyst addition results in too rapid a reaction, with the potential for "implosion" hazards, and increased costs.

According to the method, in the step (2), the temperature of the esterification reaction is 200-260 ℃, the pressure is 20-80 KPa, the time is 2-4 h, and the stirring speed is 5-20 rpm; the intrinsic viscosity of the esterification reaction product is 0.10-0.25 dL/g.

The stirring speed is controlled to be 5-20 rpm, the esterification reaction time is determined according to the types of dibasic acid and dihydric alcohol, the reaction time is 2-4 h, and the esterification rate is ensured to reach more than 96%; the intrinsic viscosity of the esterification reaction product is controlled to be 0.10-0.25 dL/g.

According to the method, in the step (3), the stirring speed of mixing and pulping is 10-30 rpm, the time is 0.5-1.0 h, and the temperature is 30-60 ℃; at the moment, only the viscosity of the system is low in the material mixing stage, and the mixing process of the materials can be realized without overhigh stirring speed or overlong stirring time, so that the stirring speed of mixing and beating is controlled to be 5-25 rpm, the time is 0.5-1.0 h, the temperature is 30-60 ℃, the stirring speed and the time of mixing and beating can be reduced in adaptability but are not too excessive, the effective mixing of the materials cannot be realized even if the stirring speed is too low and the stirring time is too low, the modified copolymerization component can be melted at the temperature, the sufficient mixing is realized, the waste of heat is caused when the temperature is too high, the melting cannot be realized if the temperature is too low, and the mixing effect is reduced.

In the method, in the step (4), the temperature of the pre-polycondensation reaction is 220-270 ℃, the pressure is 0.5-1.0 KPa, the time is 0.5-2.5 h, the stirring speed is 5-15 rpm, the temperature of the final polycondensation reaction is 220-270 ℃, the pressure is 0-200 Pa, the time is 1.0-3.0 h, and the stirring speed is 5-10 rpm;

the modified copolymerization component and the nucleating agent are added after the esterification reaction of the dibasic acid and the dibasic alcohol is completed. The hydroxyl-terminated modified copolymerization component contains 4-14 carbon atoms and is-CH₂CH₂-、-CH₂OCH₂-and-CH₂OOCH₂-one or more of aliphatic diols in which the repeating units are simultaneously terminated with hydroxyl groups; the nano inorganic nucleating agent is divided into inert inorganic powder and inorganic powder with catalytic reactivity, and the selection category is determined according to the addition amount of the modified copolymerization component; when the addition amount of the modified copolymerization component is that the mass ratio of the dibasic acid to the glycol esterification product is 3: 7-5: 5, the nano inorganic nucleating agent is selected to be inert inorganic powder comprising one or more of barium sulfate, calcium carbonate and the like; when the addition amount of the modified copolymerization component is that the mass ratio of the dibasic acid to the glycol esterification product is 5: 5-6: 4, the nano inorganic nucleating agent is selected from inorganic powder with ester exchange catalytic activity, and the nano inorganic nucleating agent comprises zinc oxide and the like.

The pre-polycondensation reaction temperature is controlled to be 220-270 ℃, and can be changed within a proper range, but is not too high, because the pre-polycondensation reaction cannot be carried out due to too low reaction temperature, thermal degradation side reactions are increased in the pre-polycondensation reaction process due to too high reaction temperature, and the color of the formed product is poor.

The pre-polycondensation reaction pressure is controlled to be 0.5-1.0 KPa, compared with the final polycondensation vacuum degree, the pre-polycondensation reaction pressure can be changed in a proper range, but the pre-polycondensation reaction pressure is not too high, low viscosity prepolymer in the pre-polycondensation reaction can be pumped out due to too low pressure (namely, higher vacuum effect) to block a pipeline to cause polycondensation accidents, small molecules in the polycondensation reaction can not be removed due to too high pressure (namely, poorer vacuum effect), and the pre-polycondensation reaction can not be normally carried out.

The pre-polycondensation reaction time is controlled to be 0.5-2.5 h, can be changed within a proper range, but is not too long, the pre-polycondensation reaction time is too short, the reaction is insufficient, the pre-polycondensation reaction time is too long, thermal degradation side reactions in the pre-polycondensation reaction process at high temperature are increased, and the effective increase of the molecular weight cannot be realized.

The stirring speed of the pre-polycondensation reaction is 5-15 rpm, the viscosity of the material in the pre-polycondensation reaction process is higher than that of an esterification reaction product and lower than that of a final polycondensation reaction product, the stirring speed of the pre-polycondensation reaction can be changed within a proper range, but the stirring speed is not too high, the pre-polycondensation product with lower viscosity can be brought out together with dihydric alcohol under a vacuum environment due to the too high stirring speed, the reaction is not favorable, and the effect of uniformly stirring the material cannot be achieved due to the too low stirring speed.

The final polycondensation reaction temperature is controlled to be 220-270 ℃, the final polycondensation reaction temperature can be changed within a proper range, but the final polycondensation reaction temperature is not too high, the final polycondensation reaction cannot be carried out due to too low reaction temperature, thermal degradation side reactions are enhanced in the final polycondensation reaction process due to too high reaction temperature, and the color and luster of the formed product are poor.

The final polycondensation reaction pressure is controlled to be 0-200 Pa, and can be changed within a proper range, but is not too high, the requirement on equipment is higher due to too low pressure (namely higher vacuum effect), small molecules in the polycondensation reaction cannot be removed due to too high pressure (namely poorer vacuum effect), and the final polycondensation reaction cannot be normally carried out.

The final polycondensation reaction time is controlled to be 1.0-3.0 h, the final polycondensation reaction time can be changed in a proper range, but the final polycondensation reaction time is not too long, the number average molecular weight of the formed product is low and cannot reach the spinning grade due to too short final polycondensation reaction time, the thermal degradation side reaction of the polymer under the high-temperature condition is obviously increased due to too long final polycondensation reaction time, and the number average molecular weight of the product is rapidly reduced due to thermal degradation after the number average molecular weight of the product reaches the maximum.

The stirring speed of the final polycondensation reaction is 5-10 rpm, the viscosity of materials in the final polycondensation reaction process is higher than that of a pre-polycondensation reaction product, the higher the viscosity of the product is, the harder the stirring is, the stirring speed of the final polycondensation reaction can be changed within a proper range, but the stirring speed is not too high, the stirring effect cannot be realized for a high-viscosity polymer system by using the too high stirring speed, and meanwhile, the motor is damaged due to too high current, and the uniform stirring effect of the materials cannot be realized by using the too low stirring speed.

Example 1

（1）TiO₂-SiO₂Preparation of composite catalyst

Sequentially adding 20mL of tetraethoxysilane, ethanol, distilled water and nitric acid into a three-neck flask, uniformly mixing, placing the three-neck flask on a magnetic stirrer, heating and refluxing, setting the heating temperature to 65 ℃, the stirring speed to 820r/min, refluxing for 2h, adding 40.0g of tetrabutyl titanate into the three-neck flask after the tetraethoxysilane is completely hydrolyzed, stirring for 20min to uniformly mix the tetrabutyl titanate with reactants, slowly dripping a proper amount of distilled water by using a constant-pressure burette at a certain speed, refluxing for 2h at 65 ℃ after dripping is finished, aging for 12h at room temperature after gel is formed, drying for 12h at 110 ℃ in a blast drying oven, removing water and ethanol solvents in a reaction system, grinding the dried solid in a mortar, placing the ground powder into a muffle furnace, setting the baking temperature to 500 ℃, starting timing after the temperature reaches the set temperature, baking for 3h, taking out the baked material after baking is finished, naturally cooling to obtain TiO₂-SiO₂A composite catalyst;

(2) preparation of titanium series composite catalyst

TiO prepared in the step (1)₂-SiO₂Stirring and mixing the composite catalyst and the cobalt acetate catalyst according to a molar ratio of 1:0.1: 0.1;

(3) preparation of esterified slurry

Mixing 10 kg of terephthalic acid, 4.5 kg of ethylene glycol (the molar ratio of the alcohol to the acid is 1.2: 1) and 1g (equivalent to 100 ppm) of the titanium composite catalyst prepared in the step (2), and pulping at the stirring speed of 20rpm for 0.8h to prepare slurry;

(4) esterification reaction

Putting the slurry obtained in the step (3) into a stainless steel reactor, starting to heat for esterification reaction, starting stirring when the temperature rises to 200 ℃, wherein the temperature of the esterification reaction is 230 ℃, the pressure is 50KPa, the time is 3h, and the stirring speed is 15 rpm;

the esterification process is accompanied by micromolecular water generated by the reaction of dibasic acid and dihydric alcohol, and the quantity of the micromolecular water can judge the process of the esterification reaction; when the esterification water reaches more than 95 percent of the theoretical water outlet value, judging that the esterification reaction is finished, wherein the intrinsic viscosity of the esterification reaction product is 0.15 dL/g;

(5) preparation of modified copolymerization component slurry

Preparing slurry from 12kg of polyethylene glycol and 6g of nano inorganic nucleating agent calcium carbonate, wherein the calcium carbonate is slowly added into the polyethylene glycol, the adding time is controlled to be 15min, the stirring speed of mixing and pulping is 20rpm, the time is 0.8h, and the temperature is 45 ℃, so as to obtain modified copolymerization component slurry;

(6) polycondensation reaction

Adding the modified copolymerization component slurry obtained in the step (5), 1g of heat stabilizer triphenyl phosphite and 1g of antioxidant 1010 (tetra [ beta- (3, 5-di-tert-butyl-4-hydroxyphenyl) propionic acid ] pentaerythritol ester) into an esterification reaction product, and then carrying out a pre-polycondensation reaction and a final polycondensation reaction to obtain a reaction type functional polyester master batch; the temperature of the pre-polycondensation reaction was 250 ℃, the pressure was 0.8KPa, the time was 1.5h, the stirring rate was 10rpm, the temperature of the final polycondensation reaction was 250 ℃, the pressure was 100Pa, the time was 2.0h, and the stirring rate was 8 rpm.

Performance testing

The method for measuring the mass fraction of the modified copolymerization component in the master batch comprises the following steps: the test was carried out using a 400 MHz NMR spectrometer from Bruker, Switzerland. Weighing about 10 mg of sample at 25 deg.CTest, the solvent is CF₃And (4) COOD. The sample was left for some time after dissolution to allow the air bubbles to be removed.

The content determination method of the free unreacted modified copolymerization component comprises the following steps: placing the master batch sample in a Soxhlet extractor, and utilizing CHCl₃And/dioxane (the volume ratio of the two is 1: 2), and the extraction is carried out in a mixed solvent repeatedly under reflux for 15-18 h. And recovering the solvent after the test is finished, and removing the solvent through a rotary evaporator to obtain the free unreacted modified component.

Test results show that the mass fraction of the modified copolymerization component in the reactive functional polyester master batch is 50 percent, and the content of the free unreacted modified copolymerization component is 0.2 percent of polyethylene glycol.

The cooling crystallization temperature, the crystallization enthalpy and other measuring methods are as follows: the samples were tested using a model Q-20 DSC from TA, USA. The copolyester chips were dried under vacuum at 135 ℃ for 24 h prior to testing. Nitrogen atmosphere, heating rate: heating the test temperature from 25 ℃ to 300 ℃ at 10 ℃/min, keeping the temperature for 3 min to eliminate the thermal history, cooling the test temperature from 300 ℃ to 25 ℃, and then continuously heating the test temperature to 300 ℃. The peak appeared in the process of cooling from 300 ℃ to 25 ℃ is called as a cooling crystallization peak, and the temperature corresponding to the peak is the cooling crystallization temperature; the cooling crystallization process is an exothermic process, and the total heat released in the whole process from the beginning of crystallization to the end of crystallization corresponding to a sample with unit mass is crystallization enthalpy; the time required for the whole process from the beginning of crystallization to the completion of crystallization of the sample is the crystallization time, the semi-crystallization time t_1/2The time corresponding to the degree of crystallinity of 50%.

The test result shows that the cooling crystallization temperature of the reactive functional polyester master batch is 160 ℃, and the semi-crystallization time t_1/2=5min, enthalpy of crystallization 25J/g, degree of crystallinity 30%.

Thermal decomposition temperature measurement method: the thermogravimetric analysis was carried out using a model STA429 thermogravimetric analyzer from Netzsch, Germany. Nitrogen atmosphere, heating rate: 10 ℃/min, and the testing temperature is 30-700 ℃. And when the quality is reduced by 5% in the temperature rise process, the corresponding temperature is a test value.

The test results showed that the thermal decomposition temperature (corresponding to a 5% mass loss) was 380 ℃.

Example 2

This example 2 is substantially the same as example 1 except that the molar ratio of dibasic acid to glycol was different, and the test results are shown in table 1.

TABLE 1

Terephthalic acid addition amount

Addition amount of ethylene glycol

Molar ratio of dibasic acid to glycol

Cooling crystallization temperature

Time of semi-crystallization

Enthalpy of crystallization

Degree of crystallinity

Temperature of thermal decomposition

10kg

4.1kg

1：1.1

166℃

4.5min

28J/g

30%

385℃

10kg

4.5kg

1：1.2

160℃

5min

25 J/g

30%

380℃

10kg

5.6kg

1：1.5

158℃

5min

24J/g

28%

378℃

10kg

7.5kg

1：2.0

150℃

6.5min

22J/g

21%

370℃

The invention can realize the uniform dispersion in the system by mixing the dibasic acid, the dihydric alcohol and other auxiliary agents in the slurry preparation stage, and ensure that the subsequent esterification reaction is uniformly and stably participated in. At the moment, only the viscosity of the system is low in the material mixing stage, and the mixing process of the materials can be realized without overhigh stirring speed or overlong stirring time, so that the stirring speed of mixing and beating is controlled to be 5-25 rpm for 0.5-1.0 h, the stirring speed and time of mixing and beating can be reduced in adaptability but are not overhigh, and the effective mixing of the materials cannot be realized by overlow stirring speed and overlow stirring time.

The reaction between the dibasic acid and the dihydric alcohol belongs to the organic chemical reaction of alcohol acid, excessive dihydric alcohol in a certain range can promote the reaction to be carried out in the positive direction, and the semicrystallization time is shortened; however, the diol is too high, which results in the waste of the diol and causes the side reaction of self-polycondensation of the diol at high temperature, and the crystallinity is reduced, so the molar weight ratio of the diacid to the diol can be reduced adaptively but is not too high, and the molar weight ratio of the diacid to the diol is too low, so the semi-crystallization time is increased.

Example 3

This example 3 is substantially the same as example 1 except that the kinds of diols are different, and the test results are shown in table 2.

TABLE 2

Kind of dihydric alcohol	Cooling crystallization temperature	Time of semi-crystallization	Enthalpy of crystallization	Degree of crystallinity	Temperature of thermal decomposition
						Ethylene glycol	160℃	5min	25 J/g	30%	380℃
Third twoAlcohol(s)	150℃	3min	40 J/g	30%	390℃
						Butanediol	140℃	5min	30 J/g	25%	380℃
Pentanediol	130℃	6min	25 J/g	20%	375℃

As can be seen from the data in Table 2, the influence degrees of different types of dihydric alcohols on the performance of the polyester master batch are different, wherein ethylene glycol is used as the dihydric alcohol, and the cooling crystallization temperature is highest; the propylene glycol is used as the dihydric alcohol, so that the semi-crystallization time is shortest; the lower enthalpy of crystallization is ethylene glycol and pentanediol; ethylene glycol and propylene glycol are the more crystalline; the highest thermal decomposition temperature is achieved by using propylene glycol as the diol.

Example 4

This example 4 is substantially the same as example 1 except that the amount of polyethylene glycol added is different, and the test results are shown in Table 3.

TABLE 3

Polyethylene glycol addition amount

Nano inorganic nucleating agent

Mass fraction of modified copolymerization component

Free unreacted content

Cooling crystallization temperature

Time of semi-crystallization

Enthalpy of crystallization

Degree of crystallinity

Temperature of thermal decomposition

5 kg

Calcium carbonate

30%

0.10wt%

170℃

3min

40 J/g

36%

395℃

8 kg

Calcium carbonate

40%

0.15wt%

165℃

3.5min

35 J/g

31%

386℃

12 kg

Calcium carbonate

50%

0.20wt%

160℃

5min

25 J/g

30%

380℃

18 kg

Zinc oxide

60%

0.45wt%

145℃

7min

20 J/g

25%

375℃

As can be seen from the data in Table 3, as the amount of polyethylene glycol added gradually increases, the content of free unreacted modified copolymerization components gradually increases, the crystallization temperature gradually decreases upon cooling, the crystallization half-time gradually increases, the enthalpy of crystallization and the degree of crystallinity also gradually decrease, and the thermal decomposition temperature also gradually decreases. However, the amount of polyethylene glycol added should not be too high, and when the amount of polyethylene glycol added reaches 18kg, the content of free unreacted modifying copolymer component reaches 0.45 wt%, the half-crystallization time increases to 7min, the crystallization ability of the master batch becomes weak, and the crystallinity also decreases to 25%, so 12kg is preferable as the optimum amount of polyethylene glycol added.

Example 5

This example 5 is substantially the same as example 1 except that the nano inorganic nucleating agent was added in a different amount, and the test results are shown in Table 4.

TABLE 4

Nano inorganic nucleating agent	Cooling crystallization temperature	Time of semi-crystallization	Enthalpy of crystallization	Degree of crystallinity	Temperature of thermal decomposition
						2.4 g	165℃	4.5min	28J/g	32%	390℃
5 g	170℃	4min	30J/g	35%	395℃
						12 g	158℃	6.5min	22J/g	23%	375℃
0	130℃	120min	5 J/g	5%	300℃

As can be seen from the data in Table 4, when no nano inorganic nucleating agent is added, the semi-crystallization time is as high as 120min, the crystallinity is only 5%, and the enthalpy of crystallization is only 5J/g. The performance of the polyester master batch added with the nano inorganic nucleating agent is obviously superior to that of the polyester master batch not added with the nano inorganic nucleating agent; wherein, the addition amount of the nano inorganic nucleating agent is not suitable to be too high, and when the addition amount of the nano inorganic nucleating agent reaches 12 g (namely 0.1 percent of the mass fraction of the modified copolymerization component), the semi-crystallization time is greatly increased, and the crystallinity is greatly reduced.

Example 6

This example 6 is substantially the same as example 1 except that the esterification reaction conditions are different, and the test results are shown in Table 5.

TABLE 5

Temperature of esterification reaction	Cooling crystallization temperature	Time of semi-crystallization	Enthalpy of crystallization	Degree of crystallinity	Temperature of thermal decomposition
						200	165℃	4min	30J/g	33%	385℃
230	160℃	5min	25J/g	30%	380℃
						260	153℃	6min	20J/g	26%	375℃

According to the invention, researches show that the temperature of the esterification reaction can be changed within a proper range, but the temperature is not too high, the rate of the esterification reaction can be further accelerated by using too high temperature, but the rate of side reactions can also be accelerated, and the heat requirement in the esterification reaction and the dissolving process cannot be met by using too low temperature. Meanwhile, the esterification reaction is slightly positive, and the pressure is controlled to be 20-80 KPa in the test process, because the small molecular water is generated by the reaction in the esterification process and has a certain positive pressure, the improvement of the esterification reaction rate can be promoted. The pressure of the esterification reaction can be changed within a proper range, but the pressure is not too high, and the higher pressure can put higher requirements on an esterification reaction device.

According to the invention, the stirring speed of the esterification reaction is controlled at 5-20 rpm, the viscosity of the slurry in the esterification reaction kettle is slightly increased compared with that in the pulping kettle, the stirring speed of the esterification reaction can be changed within a proper range, but the stirring speed is not too high, the mixing of the slurry cannot be realized at too low stirring speed, the requirement on a stirrer is higher at too high stirring speed, and the energy consumption is increased.

The method determines the esterification reaction time according to the types of the dibasic acid and the dibasic alcohol, the reaction time is 2-4 h, the esterification rate is ensured to be more than 96%, the esterification reaction time can be changed within a proper range, but the esterification reaction time is not too long, the sufficient reaction of the alcoholic acid functional group cannot be ensured due to too short esterification reaction time, and the esterification rate is difficult to further improve due to too long esterification reaction time, and side reactions are increased.

According to the invention, the intrinsic viscosity of the esterification reaction product is controlled within 0.10-0.25 dL/g, the intrinsic viscosity of the esterification reaction product can be changed within a proper range, but the intrinsic viscosity of the esterification reaction product is not too high, which means low molecular weight, so that the esterification product is easy to be pumped into a vacuum pipeline when entering a polycondensation stage, and conversely, the intrinsic viscosity is too high, which means high molecular weight, so that the activity of the esterification reaction product and the dihydric alcohol ester exchange reaction in the polycondensation stage can be reduced.

The invention is based on molecular structure design and copolymerization reaction principle, and prepares the reactive functional polyester master batch by introducing high proportion of modified copolymerization components and inorganic nucleating agent into the polyester and by the combined action of the two modified components.

A high proportion of the modifying copolymeric component is incorporated into the polyester molecular chain on the basis of transesterification, since the activation energy for transesterification is lower than that for esterification. In the invention, when the mass fraction of the esterified substance formed by the modified copolymerization component, the dibasic acid and the dihydric alcohol is less than 5:5, effective copolymerization can be realized based on ester exchange reaction, and the more important problem to be solved is how to obtain the prepared master batch with certain crystallinity. Therefore, inert nucleating agents including barium sulfate, calcium carbonate and the like are introduced at the moment, the inorganic nucleating agents do not have reaction catalytic activity, play a role in heterogeneous nucleation in the master batch and improve the crystallization capacity of the master batch, and the improvement of the crystallization performance is reflected by taking the semi-crystallization time and the crystallization enthalpy value as consideration; when the addition ratio of the modified copolymerization component is further increased and the mass fraction of the esterified product formed by the modified copolymerization component, the dibasic acid and the dihydric alcohol is higher than 5:5, the problems of effective copolymerization and improvement of crystallization capacity of master batches need to be solved. Thus, at this time, a nucleating agent having catalytic reactivity, including zinc oxide and the like, is introduced. The zinc oxide nucleating agent plays a role of heterogeneous nucleation similar to an inert nucleating agent, including barium sulfate, calcium carbonate and the like, and has good ester exchange catalytic reaction activity to promote the ester exchange reaction of the modified copolymerization component and the ester.

It should be noted that the above-mentioned embodiments are only for illustrating the technical solutions of the present invention and not for limiting, and although the present invention has been described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that modifications or equivalent substitutions may be made on the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, which should be covered by the claims of the present invention.