阅读说明：本技术 聚醚酯多嵌段共聚二元醇、合成方法及反应型热熔胶应用 (Polyether ester multi-block copolymerized dihydric alcohol, synthesis method and application of reactive hot melt adhesive ) 是由 兰支利 李皞丹 戴尚衡 宋腾 凌立志 于 2020-08-04 设计创作，主要内容包括：聚醚酯多嵌段共聚二元醇、合成方法及反应型热熔胶应用,所述聚醚酯多嵌段共聚二元醇主要由以下原料制成：聚对苯二甲酸乙二醇酯、小分子二元醇、聚醚二元醇、醇解催化剂、缩聚催化剂和抗氧剂。所述合成方法是先将聚对苯二甲酸乙二醇酯、小分子二元醇、聚醚二元醇和醇解催化剂加入反应器中,氮气保护下,醇解反应,加入缩聚催化剂和抗氧剂,升温,减压缩聚反应,冷却,即成。本发明还公开了所述聚醚酯多嵌段共聚二元醇在制备反应型热熔胶上的应用。本发明聚醚酯多嵌段共聚二元醇具微相分离结构以及零下与零上玻璃化温度,与聚酯、聚醚多元醇相溶性好。本发明方法反应时间短、简单、成本低、适于工业化生产。应用所得热熔胶具高初粘及长开放时间。(Polyether ester multi-block copolymerized dihydric alcohol, a synthesis method and application of reactive hot melt adhesive, wherein the polyether ester multi-block copolymerized dihydric alcohol is mainly prepared from the following raw materials: polyethylene terephthalate, micromolecular dihydric alcohol, polyether dihydric alcohol, an alcoholysis catalyst, a polycondensation catalyst and an antioxidant. The synthesis method comprises the steps of firstly adding polyethylene terephthalate, micromolecular dihydric alcohol, polyether dihydric alcohol and an alcoholysis catalyst into a reactor, carrying out alcoholysis reaction under the protection of nitrogen, adding a polycondensation catalyst and an antioxidant, heating, carrying out reduced pressure polycondensation reaction, and cooling. The invention also discloses application of the polyether ester multi-block copolymerized dihydric alcohol in preparation of a reactive hot melt adhesive. The polyether ester multi-block copolymerized dihydric alcohol has a micro-phase separation structure and a subzero and suprazero glass transition temperature, and has good intermiscibility with polyester and polyether glycol. The method has the advantages of short reaction time, simplicity, low cost and suitability for industrial production. The hot melt adhesive has high initial adhesion and long opening time.)

1. The polyether ester multi-block copolymerized dihydric alcohol is characterized by mainly being prepared from the following raw materials: polyethylene terephthalate, micromolecular dihydric alcohol, polyether dihydric alcohol, an alcoholysis catalyst, a polycondensation catalyst and an antioxidant.

2. The polyether ester multi-block copolyol as claimed in claim 1, wherein the raw materials comprise, by weight: 30-80 parts of polyethylene terephthalate, 5-15 parts of micromolecular dihydric alcohol, 20-60 parts of polyether dihydric alcohol, 0.01-0.10 part of alcoholysis catalyst, 0.05-0.20 part of polycondensation catalyst and 0.5-3.0 parts of antioxidant.

3. The polyether ester multi-block copolyol according to claim 1 or 2, characterized in that: the molecular weight of the polyethylene terephthalate is 20000-40000; the micromolecular dihydric alcohol is one or more of ethylene glycol, 1, 2-propylene glycol or 1, 4-butanediol; the molecular weight of the polyether glycol is 200-2000; the polyether diol is one or more of polyethylene glycol, polypropylene glycol or polybutylene glycol; the alcoholysis catalyst is one or more of zinc acetate, manganese acetate or cobalt acetate; the polycondensation catalyst is one or more of alkoxy titanium, organic tin, antimony series or germanium series catalysts; the antioxidant is one or more of 1010 antioxidant, 1076 antioxidant, 1135 antioxidant, 215 antioxidant, 225 antioxidant or 220 antioxidant.

4. A method for synthesizing the polyether ester multi-block copolyol as claimed in any one of claims 1 to 3, wherein: firstly adding polyethylene terephthalate, micromolecular dihydric alcohol, polyether dihydric alcohol and alcoholysis catalyst into a reactor, heating for alcoholysis reaction under the protection of nitrogen atmosphere, then adding polycondensation catalyst and antioxidant, heating, carrying out polycondensation reaction through two-step decompression, evaporating out the micromolecular dihydric alcohol at the end base position of the polycondensation product, and cooling to obtain the polyether ester multi-block copolymerization dihydric alcohol.

5. The method for synthesizing polyether ester multi-block copolyol as claimed in claim 4, wherein: the temperature of the alcoholysis reaction is 180-200 ℃, and the time is 1.0-3.0 h; the temperature of the polycondensation reaction is 230-250 ℃; the two-step reduced pressure polycondensation reaction is as follows: reducing the pressure to-0.03-0.05 MPa vacuum degree, carrying out polycondensation reaction for 1.0-2.0 h, and then reducing the pressure to-0.095-0.098 MPa vacuum degree, carrying out polycondensation reaction for 2.0-3.0 h.

6. The application of the polyether ester multi-block copolymerized dihydric alcohol as claimed in any one of claims 1 to 3 in the preparation of reactive hot melt adhesive, wherein the polyether ester multi-block copolymerized dihydric alcohol as claimed in any one of claims 1 to 3 is used in the preparation of reactive hot melt adhesive in a mass percentage of 30 to 70% of the raw materials.

7. The application of the reactive hot melt adhesive of the polyether ester multi-block copolymerized diol as claimed in claim 6, wherein the reactive hot melt adhesive is mainly prepared from the following raw materials in parts by weight: 30 to 70 parts of the polyether ester block copolymer polyol, 1 to 49 parts of polyether polyol and 1 to 49 parts of polyester polyol as claimed in any one of claims 1 to 3, wherein the total of the polyether polyol and the polyester polyol is 20 to 50 parts, 10 to 20 parts of polyisocyanate and 2 to 8 parts of an auxiliary.

8. The reactive hot melt adhesive application of polyetherester multi-block copolyols in claim 7, wherein: the molecular weight of the polyether polyol is 1000-4000; the polyether polyol is polypropylene glycol and/or polybutylene glycol; the molecular weight of the polyester polyol is 2000-6000; the polyester polyol is one or more of polyester polyols of 72 series, 73 series or 71 series; the polyisocyanate is one or more of diphenylmethane diisocyanate, toluene diisocyanate or isophorone diisocyanate; the auxiliary agent is one or more of tackifying resin, defoaming agent or antioxidant.

9. The application of the reactive hot melt adhesive of the polyether ester multi-block copolymerized dihydric alcohol as claimed in claim 7 or 8, wherein the preparation method of the reactive hot melt adhesive comprises the following steps: dehydrating the polyether ester multi-block copolymerized dihydric alcohol, the polyether polyol and the polyester polyol as claimed in any one of claims 1 to 3, cooling, adding the polyisocyanate, stirring at a high speed, heating for reaction, adding the auxiliary agent, stirring, defoaming in vacuum, discharging and packaging in a nitrogen atmosphere.

10. The reactive hot melt adhesive application of polyetherester multi-block copolyols in claim 9, wherein: the temperature of the dehydration treatment is 110-130 ℃, the vacuum degree is-0.08-0.10 MPa, and the time is 1-3 h; the temperature is reduced to be less than or equal to 90 ℃; the rotating speed of the high-speed stirring is 60-200 r/min; the heating reaction is carried out at the temperature of 70-110 ℃ for 3-5 h; and the time for stirring after the addition of the auxiliary agent is 10-30 min.

Technical Field

The invention relates to a copolymerized dihydric alcohol, a synthetic method and application, in particular to a polyether ester multi-block copolymerized dihydric alcohol, a synthetic method and application in reactive hot melt adhesives.

Background

Reaction type polyurethane hot melt adhesive (PUR), it has better just gluing and quick positioning performance, through the moisture cure reaction after the glueing, make the system take place intermolecular cross-linking, make glue film intensity, heat resistance, water proofness, chemical resistance can be stronger than traditional hot melt adhesive, have the advantage of hot melt adhesive and reaction type adhesive concurrently, be a green and novel gluing agent that productivity ratio is high when using.

The main raw materials for preparing the PUR are polyester polyol, polyether polyol and polyisocyanate, but the conventional polyester polyol and polyether polyol have poor compatibility due to large polarity difference. The polyester polyols used in the preparation of PURs are generally classified into liquid polyester polyols, crystalline polyester polyols and amorphous polyester polyols, corresponding to 72 series, 73 series and 71 series, respectively, of winning companies. PURs prepared using liquid polyester polyols generally have long open times but have low initial tack; PURs prepared from crystalline polyester polyols generally have short opening time and general initial viscosity; PURs prepared using amorphous polyester polyols generally have a short open time but a high initial tack. Many application scenarios for PUR require that they have both a long open time and a large initial tack performance. The existing polyester polyol does not basically have a polyol raw material which can meet the performance requirement, so the PUR performance requirements of high initial viscosity and long open time are generally met by compounding various polyester polyol raw materials and adding a thermoplastic high polymer material, but the preparation method increases the difficulty of the production process and formula modulation.

The polyether ester elastomer is a thermoplastic high molecular material mainly applied to elastomer fibers, and the molecular structure of the polyether ester elastomer is provided with a hard segment polyester segment and a soft segment polyether segment, and is a polyether polyester block polymer structure. Because the existing polyether ester elastomer is mostly a thermoplastic macromolecule of a super macromolecule, the polyether ester elastomer can not be used as a polyol raw material of the PUR hot melt adhesive.

The conventional polyether ester block copolymer is generally prepared by polycondensation using terephthalic acid or dimethyl terephthalate (DMT), diols such as ethylene glycol, butanediol and propylene glycol, and polyether diols such as PEG, PPG and PTMG as raw materials. However, when terephthalic acid is used as a raw material, the dissolution temperature is high, and thus the reaction temperature is required to exceed 240 ℃, and when DMT is used as a raw material, DMT is easy to sublimate and easily blocks a rectification channel. Moreover, the preparation method can only obtain the linear polymer with two blocks of PET-PTMG or three blocks of PET-PTMG-PET and PTMG-PET-PTMG, and the polyether ester copolymerized diol with multi-block structure of PET-PTMG … … is difficult to obtain.

Disclosure of Invention

The invention aims to solve the technical problem of overcoming the defects in the prior art and providing the polyether ester multi-block copolymerized dihydric alcohol which has a molecular weight suitable for PUR, has a microphase separation structure, two vitrification temperatures of below zero and above, has good intermiscibility with conventional polyester polyol and polyether polyol, and has the characteristics of high initial adhesion and long open time performance.

The invention further aims to solve the technical problem of overcoming the defects in the prior art and provide a synthesis method of polyether ester multi-block copolymerized dihydric alcohol, which has the advantages of short reaction time, simple process, no solvent in the preparation process, low cost and suitability for industrial production.

The invention further aims to solve the technical problem of overcoming the defects in the prior art and provides application of the reactive hot melt adhesive prepared from the polyether ester multi-block copolymerized dihydric alcohol, wherein the reactive hot melt adhesive has the characteristics of high initial adhesion and long open time.

The technical scheme adopted by the invention for solving the technical problems is as follows: the polyether ester multi-block copolymerized dihydric alcohol is mainly prepared from the following raw materials: polyethylene terephthalate, micromolecular dihydric alcohol, polyether dihydric alcohol, an alcoholysis catalyst, a polycondensation catalyst and an antioxidant.

Polyethylene terephthalate (PET) is a widely used thermoplastic polymer material from which conventional beverage bottles and polyester fibers are processed, but which cannot be used as a polyol raw material for PUR hot melt adhesives. In the invention, the hard segment polyester structure provided by PET is subjected to alcoholysis reaction with micromolecular dihydric alcohol to obtain an oligomeric PET structure, and then the oligomeric PET structure is subjected to polycondensation reaction with polyether dihydric alcohol to obtain polyether ester copolymerized dihydric alcohol with a multi-block structure meeting PUR application. The polyester segment with hard segment in the molecular structure of the oligomeric PET is subjected to polycondensation reaction with polyether diol, the polyether diol provides a soft segment structure, the polyether ester is a block polymer structure with polyether-polyester microphase separation, the block structure characteristics of the polyester polyether enable the polyether to have good intermiscibility with conventional polyester polyol and polyether polyol, and the block structure characteristics of the polyether-polyester microphase separation enable the polyether polyester to have two glass transition temperatures lower than zero and higher than zero.

The micromolecular dihydric alcohol mainly has the function of accelerating the dissolution of the PET raw material and is used as an alcoholysis raw material to participate in the alcoholysis reaction.

The polyether diol mainly has the function of providing a soft segment polyether structure in polyether ester multi-block copolymerized diol, plays a role of a solvent in alcoholysis reaction, and is subjected to polycondensation reaction on the terminal position of oligomeric PET in the subsequent polycondensation reaction to obtain the multi-block polyether ester copolymerized diol.

The alcoholysis catalyst mainly has the effects of improving the reaction speed, reducing the temperature of alcoholysis reaction and accelerating the reaction process.

The polycondensation catalyst has the main functions of accelerating the polycondensation reaction speed of the polyether glycol and the oligomeric PET, reducing the polycondensation reaction temperature and accelerating the polycondensation reaction process.

The antioxidant mainly has the function of reducing the occurrence of oxidation side reactions under the high-temperature polycondensation reaction.

Preferably, the polyether ester multi-block copolymerized dihydric alcohol comprises the following raw materials in parts by weight: 30-80 parts of polyethylene terephthalate, 5-15 parts of micromolecular dihydric alcohol, 20-60 parts of polyether dihydric alcohol, 0.01-0.10 part of alcoholysis catalyst, 0.05-0.20 part of polycondensation catalyst and 0.5-3.0 parts of antioxidant. The content of PET determines the content of hard segments in the polyether ester product, and also determines the size of the glass transition temperature above zero, if the amount is too much, the glass transition temperature is too high, the prepared PUR hot melt adhesive is too hard and brittle, and if the amount is too little, the glass transition temperature is too low, and the prepared PUR hot melt adhesive is low in initial viscosity; the use amount of the micromolecular dihydric alcohol determines the size of the oligomeric PET block obtained in the alcoholysis reaction, if the use amount is too large, the molecular weight of the oligomeric PET block is too small, the glass transition temperature of a final product is too small, and if the use amount is too small, the molecular weight of the oligomeric PET block is too large, so that the block number and the hard segment characteristics of polyether ester are influenced; the content of the polyether diol determines the content of soft segments in the polyether ester product, and also determines the size of the glass transition temperature below zero, if the content is too much, the glass transition temperature is too low, the prepared PUR hot melt adhesive is too soft and insufficient in initial adhesion, and if the content is too little, the glass transition temperature is too high, and the opening time of the prepared PUR hot melt adhesive is not long.

More preferably, the polyether ester multi-block copolymerized dihydric alcohol comprises the following raw materials in parts by weight: 30-80 parts of polyethylene terephthalate, 5-15 parts of micromolecular dihydric alcohol, 20-60 parts of polyether dihydric alcohol, 0.01-0.10 part of alcoholysis catalyst, 0.05-0.20 part of polycondensation catalyst and 0.5-3.0 parts of antioxidant.

Preferably, the molecular weight of the polyethylene terephthalate is 20000-40000. The PET is derived from one or more of pure PET granules or powder, recycled PET bottle scraps or PET fiber leftover materials/cut scraps. PET is a widely used thermoplastic polymer material, conventional beverage bottles and polyester fibers are all processed from the PET, and a large amount of leftover materials and recycled PET raw materials exist in the production. The existing PET chemical regeneration method obtains terephthalic acid through hydrolysis or alcoholysis, or DMT raw material and ethylene glycol, the added value of the product is not greatly increased, and polyether ester multi-block copolymerized dihydric alcohol prepared by using PET as raw material is used as basic polyhydric alcohol raw material to be applied to the preparation of PUR hot melt adhesive, so that the added value can be greatly improved.

Preferably, the small molecular diol is one or more of ethylene glycol, 1, 2-propylene glycol or 1, 4-butanediol and the like.

Preferably, the polyether glycol has a molecular weight of 200 to 2000 (more preferably 400 to 800). The polyether diol with the molecular weight has a better solvent effect in the alcoholysis reaction, and can perform a faster polycondensation reaction on the end group of the PET oligomer in the subsequent polycondensation reaction, and the obtained polyether ester multi-block copolymerized diol has better PUR application performance.

Preferably, the polyether glycol is one or more of polyethylene glycol, polypropylene glycol or polybutylene glycol.

Preferably, the alcoholysis catalyst is one or more of zinc acetate, manganese acetate or cobalt acetate.

Preferably, the polycondensation catalyst is one or more of alkoxy titanium, organic tin, antimony-based or germanium-based catalysts and the like. More preferably, the titanium alkoxide is tetrabutyl titanate and/or tetraisobutyl titanate.

Preferably, the antioxidant is one or more of 1010 antioxidant, 1076 antioxidant, 1135 antioxidant, 215 antioxidant, 225 antioxidant or 220 antioxidant.

The technical scheme adopted for further solving the technical problems is as follows: the synthesis method of polyether ester multi-block copolymerized dihydric alcohol comprises the steps of firstly adding polyethylene terephthalate, micromolecular dihydric alcohol, polyether dihydric alcohol and alcoholysis catalyst into a reactor, heating for alcoholysis reaction under the protection of nitrogen atmosphere, then adding polycondensation catalyst and antioxidant, heating, carrying out polycondensation reaction through two-step pressure reduction, evaporating out the end base micromolecular dihydric alcohol of a polycondensation product, and cooling to obtain the polyether ester multi-block copolymerized dihydric alcohol.

The reaction formula of the synthesis process of the polyether ester multi-block copolymerized dihydric alcohol is shown as follows:

in the reaction process, the small molecular diol performs alcoholysis reaction on the PET under the action of an alcoholysis catalyst, and the PET raw material with the molecular weight of 2-4 ten thousand is subjected to alcoholysis reaction to obtain a PET polyester oligomer with the molecular weight of about 500-1000; and (3) carrying out polycondensation reaction on the terminal position of the PET polyester oligomer by polyether diol under the action of a polycondensation catalyst to release terminal position micromolecule diol, thereby obtaining polyether ester multi-block copolymerized diol with molecular weight of 2000-5000 suitable for PUR preparation.

Preferably, the temperature of the alcoholysis reaction is 180-200 ℃ and the time is 1.0-3.0 h. At the temperature, the PET raw material is favorably swelled by the micromolecule dihydric alcohol and the polyether dihydric alcohol, and is subjected to alcoholysis reaction with the micromolecule dihydric alcohol to a certain extent to form a homogeneous solution system; if the temperature is too low, the reaction speed is too slow, so that PET polyester oligomer with lower molecular weight is difficult to obtain, and the swelling of the PET oligomer is insufficient, so that a homogeneous system cannot be formed; if the temperature is too high, the alcoholysis reaction speed is difficult to control, so that a PET polyester oligomer with too low molecular weight is obtained, in the subsequent polycondensation reaction, polyether ester multi-block copolymerized dihydric alcohol with the PET function is difficult to obtain, and if the boiling point of the small molecular dihydric alcohol is exceeded, most of the small molecular dihydric alcohol is converted into gas phase, so that the alcoholysis and the dissolution assisting effects on the PET are not achieved.

Preferably, the temperature of the polycondensation reaction is 230-250 ℃. And at the polycondensation temperature, the polyether diol can carry out polycondensation reaction on the PET polyester oligomer until the PET polyester oligomer is polycondensed into polyether ester multi-block copolymerized diol with the molecular weight of 2000-5000.

Preferably, the two-step reduced pressure polycondensation reaction means: reducing the pressure to-0.03-0.05 MPa vacuum degree, carrying out polycondensation reaction for 1.0-2.0 h, and then reducing the pressure to-0.095-0.098 MPa vacuum degree, carrying out polycondensation reaction for 2.0-3.0 h. The first step of decompression is carried out under a lower vacuum degree, and the main purpose is to further carry out alcoholysis reaction of the small molecular diol on the PET, remove the small molecular diol which is not reacted completely and simultaneously carry out polycondensation reaction with the polyether diol in a small amount; the second step of decompression is carried out under high vacuum condition, and the polyether diol with larger molecular weight carries out polycondensation reaction on the end group in the oligomeric PET structure to remove the end group micromolecule diol, and the reaction can be better carried out under high vacuum.

The technical scheme adopted by the invention for further solving the technical problems is as follows: the application of the reactive hot melt adhesive of the polyether ester multi-block copolymerized dihydric alcohol is characterized in that the polyether ester multi-block copolymerized dihydric alcohol accounts for 30-70% of the raw materials by mass percent and is applied to the preparation of the reactive hot melt adhesive. The polyether ester multi-block copolymerized dihydric alcohol is a main polyhydric alcohol raw material for preparing the PUR hot melt adhesive, and any other components can be modulated according to the requirements.

Preferably, the reactive hot melt adhesive is mainly prepared from the following raw materials in parts by weight: 30-70 parts of polyether ester block copolymer polyol, 1-49 parts of polyether polyol and 1-49 parts of polyester polyol, wherein the total amount of the polyether polyol and the polyester polyol is 20-50 parts, 10-20 parts of polyisocyanate and 2-8 parts of an auxiliary agent. The polyether ester multi-block copolymerized dihydric alcohol has longer polyether chain segments and polyester chain segments, so that the polyether ester multi-block copolymerized dihydric alcohol can be well mixed with polyether polyol and polyester polyol respectively without phase separation; when the conventional polyether polyol and the polyester polyol coexist, the addition of the polyether ester multi-block copolymerized dihydric alcohol is equivalent to the addition of respective solubilizer, and the conventional polyether polyol and the polyester polyol can be well mixed without phase separation through the solubilizing effect of the polyether ester multi-block copolymerized dihydric alcohol. Under the dosage range of the raw materials, the PUR hot melt adhesive with larger initial adhesion and longer open time can be obtained more conveniently.

More preferably, the reactive hot melt adhesive is mainly prepared from the following raw materials in parts by weight: 40-60 parts of polyether ester block copolyol, 5-30 parts of polyether polyol and 10-40 parts of polyester polyol, wherein the total amount of the polyether polyol and the polyester polyol is 20-50 parts, 10-20 parts of polyisocyanate and 2-8 parts of an auxiliary agent.

Preferably, the molecular weight of the polyether polyol is 1000-4000.

Preferably, the polyether polyol is polypropylene glycol and/or polybutylene glycol.

Preferably, the molecular weight of the polyester polyol is 2000-6000.

Preferably, the polyester polyol is one or more of polyester polyols of 72 series, 73 series or 71 series and the like. More preferably, the winning type 72 series is one or more of winning type 7210, winning type 7230 or winning type 7250, the winning type 73 series is winning type 7360, and the winning type 71 series is winning type 7130 and/or winning type 7150.

Preferably, the polyisocyanate is one or more of diphenylmethane diisocyanate, toluene diisocyanate, isophorone diisocyanate and the like.

Preferably, the auxiliary agent is one or more of tackifying resin, defoaming agent or antioxidant. The amount of each component in the auxiliary is selected according to the prior art.

Preferably, the preparation method of the reactive hot melt adhesive comprises the following steps: dehydrating the polyether ester multi-block copolymerized dihydric alcohol, the polyether polyol and the polyester polyol, cooling, adding the polyisocyanate, stirring at a high speed, heating for reaction, adding the auxiliary agent, stirring, defoaming in vacuum, discharging in a nitrogen atmosphere, and packaging.

Preferably, the temperature of the dehydration treatment is 110-130 ℃, the vacuum degree is-0.08-0.10 MPa, and the time is 1-3 h.

Preferably, the temperature is reduced to be less than or equal to 90 ℃.

Preferably, the rotation speed of the high-speed stirring is 60-200 r/min (more preferably 80-150 r/min).

Preferably, the heating reaction temperature is 70-110 ℃, and the time is 3-5 h.

Preferably, the time for stirring after adding the auxiliary agent is 10-30 min.

The invention has the following beneficial effects:

(1) the polyether ester multi-block copolymerized dihydric alcohol has the molecular weight of 2000-5000, the dispersity is 2-3, the structural characteristics of hard and soft segment microphase separation are realized, the glass transition temperature is zero or above, and the intermiscibility with the conventional polyester polyol and polyether polyol is good;

(2) after the PUR hot melt adhesive prepared from the polyether ester multi-block copolymerized dihydric alcohol is pasted for 5min, the 90-degree peel strength is greater than 8.5N/25mm, and the opening time is greater than 30min, so that the PUR hot melt adhesive has the performance characteristics of high initial adhesion and long opening time, and is suitable for application scenes such as coating, flat pasting and the like;

(3) the method has the advantages of short reaction time, simple process, no solvent in the preparation process, low cost and suitability for industrial production.

Drawings

FIG. 1 is a chart of the IR spectrum of a polyether ester multi-block copolyol of example 1 of the present invention;

FIG. 2 is a Differential Scanning Calorimetry (DSC) chart of a polyether ester multi-block copolyol of example 1 of the present invention.

Detailed Description

The invention is further illustrated by the following examples and figures.

The sources of polyethylene terephthalate (PET) used in the examples of the present invention are in order: PET 1: the molecular weight is 20000-40000, and PET powder is purchased from the market; PET 2: the molecular weight is 20000-40000, and the recycled mineral water bottle is used; PET 3: the molecular weight is 20000-40000, and the PET fibers are cut into pieces; the 1010 antioxidant, 1076 antioxidant, 220 antioxidant and 215 antioxidant are all commercial products; the polyester polyols of Yingchuang 7210 type, Yingchuang 7230 type, Yingchuang 7250 type, Yingchuang 7360 type, Yingchuang 7130 type and Yingchuang 7150 type are used, the molecular weights are 3500, 5500, 3500, 3000 and 2600 in sequence, and are purchased from Asahi Chuan chemical (Suzhou) Limited company; the starting materials or chemicals used in the examples of the present invention are, unless otherwise specified, commercially available in a conventional manner.

Polytetramethylene glycol is abbreviated as PTMG, polypropylene glycol is abbreviated as PPG, polyethylene glycol is abbreviated as PEG, and diphenylmethane diisocyanate is abbreviated as MDI.

Examples 1 to 4 of polyether ester multiblock copolymerized diol

The raw materials and the parts by weight of the polyether ester multi-block copolyol in examples 1 to 4 are shown in Table 1.

TABLE 1 polyether ester multiblock copolyol raw materials and parts by weight of examples 1 to 4

Note: in the table, "-" indicates no addition.

Method for synthesizing polyether ester multi-block copolymerized diol example 1

According to the raw materials and the weight portions in the example 1 in the table 1, firstly adding polyethylene terephthalate, micromolecular dihydric alcohol, polyether dihydric alcohol and alcoholysis catalyst into a reactor, heating to 190 ℃ under the protection of nitrogen atmosphere for alcoholysis reaction for 1.5h, then adding polycondensation catalyst and antioxidant, heating to 240 ℃, firstly reducing the pressure to-0.04 MPa vacuum degree, carrying out polycondensation reaction for 1h, then reducing the pressure to-0.095 MPa vacuum degree, carrying out polycondensation reaction for 3h, evaporating out micromolecular dihydric alcohol at the end base position of a polycondensation product, and cooling to obtain PET/PTMG type polyether ester multi-block copolymerization dihydric alcohol, wherein PET/PTMG1 is used as a PET/PTMG.

The molecular weight of the PET/PTMG type polyether ester multi-block copolymerized dihydric alcohol obtained in the embodiment of the invention is 4800 and the dispersity is 2.6 through GPC measurement.

As shown in FIG. 1, in the infrared spectrogram of PET/PTMG type polyether ester multi-block copolymerized dihydric alcohol obtained in the example of the invention, the infrared spectrogram is 3485cm^-1The absorption peak of hydroxyl group is weaker, which shows that the hydroxyl group is a hydroxyl-terminated high molecular material with larger molecular weight, 2939cm^-1And 2855 cm^-1Is treated as methylene C-H stretching vibration peak, 1714 cm^-1And 1269 cm^-1Is located at 1576cm of strong ARCOO stretching vibration peak^-1And 1451 cm^-1Is located at 1099cm of an in-plane bending vibration peak of a carbon-carbon double bond in a benzene ring^-1The strong absorption peak is the stretching vibration peak of typical fatty ether, 727 cm^-1The position is a hydrocarbon out-of-plane deformation vibration peak in a benzene ring; therefore, the PET/PTMG type polyether ester multi-block copolymer diol obtained in the embodiment of the invention has a typical structure of polyether and polyester, and is polyether ester multi-block copolymer diol.

As shown in FIG. 2, in the DSC chart of the PET/PTMG type polyether ester multi-block copolymerized diol obtained in the example of the present invention, two glass transition temperatures of-8.99 ℃ and 45.95 ℃ exist, which shows that the PET/PTMG type polyether ester multi-block copolymerized diol has a microphase separation structure.

The PET/PTMG type polyether ester multi-block copolymerized dihydric alcohol obtained in the embodiment of the invention is respectively and uniformly mixed with PPG2000 and PBA2000 with equal mass at the temperature of 110 ℃, and then is kept stand for 2 hours at the temperature of 100 ℃, and no phase separation phenomenon is found, which indicates that the PET/PTMG type polyether ester multi-block copolymerized dihydric alcohol obtained in the embodiment of the invention has good intermiscibility with conventional polyether polyol and polyester polyol.

Method for synthesizing polyether ester multi-block copolymerized diol example 2

According to the raw materials and the weight parts in the example 2 in the table 1, firstly adding polyethylene terephthalate, micromolecular dihydric alcohol, polyether dihydric alcohol and alcoholysis catalyst into a reactor, heating to 185 ℃ under the protection of nitrogen atmosphere for alcoholysis reaction for 2h, then adding a polycondensation catalyst and an antioxidant, heating to 235 ℃, firstly reducing the pressure to-0.03 MPa of vacuum degree, carrying out polycondensation reaction for 1.5h, then reducing the pressure to-0.098 MPa of vacuum degree, carrying out polycondensation reaction for 2.5h, evaporating out the micromolecular dihydric alcohol at the end base position of the polycondensation product, and cooling to obtain the PET/PPG type polyether ester multi-block copolyol, which is PET/PPG 2.

The molecular weight of the PET/PPG type polyether ester multi-block copolymerized dihydric alcohol obtained in the embodiment of the invention is 4100 and the dispersity is 2.4 through GPC measurement.

Through infrared spectrum detection, the PET/PPG type polyether ester multi-block copolymerized dihydric alcohol obtained in the embodiment of the invention has a typical structure of polyether and polyester, and is polyether ester multi-block copolymerized dihydric alcohol.

Through detection, the PET/PPG type polyether ester multi-block copolymerized dihydric alcohol obtained in the embodiment of the invention has two glass transition temperatures of-25 ℃ and 33 ℃, which shows that the PET/PPG type polyether ester multi-block copolymerized dihydric alcohol has a microphase separation structure.

The PET/PPG type polyether ester multi-block copolymerized dihydric alcohol obtained in the embodiment of the invention is respectively and uniformly mixed with PPG2000 and PBA2000 with equal mass at the temperature of 110 ℃, and then is kept stand for 2 hours at the temperature of 100 ℃, and no phase separation phenomenon is found, so that the PET/PPG type polyether ester multi-block copolymerized dihydric alcohol obtained in the embodiment of the invention has good intermiscibility with conventional polyether polyol and polyester polyol.

Method for synthesizing polyether ester multi-block copolymerized diol example 3

According to the raw materials and the weight parts in the embodiment 3 in the table 1, firstly, adding polyethylene terephthalate, micromolecular dihydric alcohol, polyether dihydric alcohol and alcoholysis catalyst into a reactor, heating to 195 ℃ under the protection of nitrogen atmosphere for alcoholysis reaction for 1.5h, then adding polycondensation catalyst and antioxidant, heating to 245 ℃, then decompressing to-0.05 MPa of vacuum degree, performing polycondensation reaction for 1h, then decompressing to-0.098 MPa of vacuum degree, performing polycondensation reaction for 2.5h, evaporating out the micromolecular dihydric alcohol at the end base position of the polycondensation product, and cooling to obtain the PET/PEG type polyether ester multi-block copolyol, which is PET/PEG 3.

Through GPC measurement, the molecular weight of the PET/PEG type polyether ester multi-block copolymerized dihydric alcohol obtained in the embodiment of the invention is 3500, and the dispersity is 2.3.

Through infrared spectrum detection, the PET/PEG type polyether ester multi-block copolymerized dihydric alcohol obtained in the embodiment of the invention has a typical structure of polyether and polyester, and is polyether ester multi-block copolymerized dihydric alcohol.

Through detection, the PET/PEG type polyether ester multi-block copolymerized dihydric alcohol obtained in the embodiment of the invention has two glass transition temperatures of-34 ℃ and 28 ℃, which shows that the PET/PEG type polyether ester multi-block copolymerized dihydric alcohol has a microphase separation structure.

The PET/PEG type polyether ester multi-block copolymerized dihydric alcohol obtained in the embodiment of the invention is respectively and uniformly mixed with PPG2000 and PBA2000 with equal mass at the temperature of 110 ℃, and then is kept stand for 2 hours at the temperature of 100 ℃, and no phase separation phenomenon is found, so that the PET/PEG type polyether ester multi-block copolymerized dihydric alcohol obtained in the embodiment of the invention has good intermiscibility with conventional polyether polyol and polyester polyol.

Method for synthesizing polyether ester multi-block copolymerized diol example 4

According to the raw materials and the weight portions in the example 4 in the table 1, firstly, polyethylene terephthalate, micromolecular dihydric alcohol, polyether dihydric alcohol and alcoholysis catalyst are added into a reactor, the temperature is increased to 180 ℃ under the protection of nitrogen atmosphere for alcoholysis reaction for 2.5h, then polycondensation catalyst and antioxidant are added, the temperature is increased to 250 ℃, the pressure is reduced to-0.04 MPa vacuum degree, the polycondensation reaction is carried out for 2h after 2h, the pressure is reduced to-0.097 MPa vacuum degree, polycondensation reaction is carried out for 2h, micromolecular dihydric alcohol at the end base position of a polycondensation product is evaporated, and the PET/PTMG type polyether ester multi-block copolymerization dihydric alcohol is obtained by cooling, and PET/PTMG4 is marked as PET/PTMG.

The molecular weight of the PET/PTMG type polyether ester multi-block copolymerized dihydric alcohol obtained in the embodiment of the invention is 4500 and the dispersity is 2.5 through GPC measurement.

By infrared spectrum detection, the PET/PTMG type polyether ester multi-block copolymerized diol obtained in the embodiment of the invention has a typical structure of polyether and polyester, and is polyether ester multi-block copolymerized diol.

Through detection, the PET/PTMG type polyether ester multi-block copolymerized dihydric alcohol obtained in the embodiment of the invention has two glass transition temperatures of-15 ℃ and 40 ℃, which shows that the PET/PTMG type polyether ester multi-block copolymerized dihydric alcohol has a microphase separation structure.

The PET/PTMG type polyether ester multi-block copolymerized dihydric alcohol obtained in the embodiment of the invention is respectively and uniformly mixed with PPG2000 and PBA2000 with equal mass at the temperature of 110 ℃, and then is kept stand for 2 hours at the temperature of 100 ℃, and no phase separation phenomenon is found, which indicates that the PET/PTMG type polyether ester multi-block copolymerized dihydric alcohol obtained in the embodiment of the invention has good intermiscibility with conventional polyether polyol and polyester polyol.

Application examples 1-4 of reactive hot melt adhesive of polyether ester multi-block copolymerized dihydric alcohol

PET/PTMG1, PET/PPG2, PET/PEG3 and PET/PTMG4 are respectively applied to the preparation of the reactive hot melt adhesive in mass percent of 40 percent, 50 percent, 60 percent and 45 percent of the raw materials.

1) The raw materials and the weight parts of the specific reactive hot melt adhesives of examples 1-4 and comparative examples 1 and 2 are shown in table 2.

TABLE 2 raw materials and parts by weight of reactive hot melt adhesives in examples 1-4 and comparative examples 1 and 2

Note: in the table, "-" indicates no addition.

2) Specific methods for preparing reactive hot melt adhesives, examples 1 to 4, are as follows.

Preparation method of reactive hot melt adhesive example 1:

according to the raw materials and the weight parts in the example 1 in the table 2, the polyether ester multi-block copolymerized dihydric alcohol, the polyether polyol and the polyester polyol are dehydrated for 2h at the temperature of 120 ℃ and the pressure of-0.09 MPa, the polyisocyanate is added after the temperature is reduced to 90 ℃, the auxiliary agent is added after the heating reaction is carried out for 4h at the temperature of 100r/min under the high-speed stirring of 100 ℃, the stirring is carried out for 20min, the vacuum defoaming is carried out, and the materials are discharged and packaged in the nitrogen atmosphere to obtain the hot melt adhesive 1.

Preparation method of reactive hot melt adhesive example 2:

according to the raw materials and the weight parts of the raw materials in the example 2 in the table 2, firstly, the polyether ester multi-block copolymerized dihydric alcohol, the polyether polyol and the polyester polyol are dehydrated for 1.5h at the temperature of 125 ℃ and the pressure of-0.10 MPa, after the temperature is reduced to 85 ℃, the polyisocyanate is added, the mixture is heated and reacted for 3.5h at the temperature of 90 ℃ under the high-speed stirring of 150 r/min, the auxiliary agent is added, after the stirring for 15min, the mixture is defoamed in vacuum, and the mixture is discharged and packaged in the nitrogen atmosphere, so that the hot melt adhesive 2 is obtained.

Preparation method of reactive hot melt adhesive example 3:

according to the raw materials and the weight parts of the raw materials in the embodiment 3 in the table 2, the polyether ester multi-block copolymerized dihydric alcohol, the polyether polyol and the polyester polyol are dehydrated for 2.5h at the temperature of 115 ℃ and the pressure of-0.085 MPa, after the temperature is reduced to 85 ℃, the polyisocyanate is added, the mixture is heated and reacted for 5h at the temperature of 80 ℃ under the high-speed stirring of 80 r/min, the auxiliary agent is added, the mixture is stirred for 25min, the mixture is defoamed in vacuum, and the mixture is discharged and packaged in the nitrogen atmosphere to obtain the hot melt adhesive 3.

Preparation method of reactive hot melt adhesive example 4:

according to the raw materials and the weight portions of the raw materials in the embodiment 4 in the table 2, firstly, the polyether ester multi-block copolymerized dihydric alcohol, the polyether polyol and the polyester polyol are dehydrated for 2h at the temperature of 120 ℃ and the pressure of-0.09 MPa, after the temperature is reduced to 88 ℃, the polyisocyanate is added, the auxiliary agent is added after the heating reaction is carried out for 4h at the temperature of 110 ℃ under the high-speed stirring of 120 r/min, after the stirring is carried out for 20min, the vacuum defoaming is carried out, and the materials are discharged and packaged under the nitrogen atmosphere, thus obtaining the hot melt adhesive 4.

Preparation method of reactive Hot melt adhesive comparative example 1

The comparative example differs from the preparation of a reactive hotmelt only in that example 1: the preparation was carried out according to the raw materials and parts by weight as described in comparative example 1 in Table 2. The same as in example 1.

Preparation method of reactive Hot melt adhesive comparative example 2

The comparative example differs from the preparation of a reactive hotmelt only in that example 1: the preparation was carried out according to the raw materials and parts by weight as described in comparative example 2 in Table 2. The same as in example 1.

The reactive hot melt adhesives obtained in examples 1 to 4 of the invention and comparative examples 1 and 2 were subjected to initial adhesion test and open time test.

1) The initial adhesion testing method comprises the following steps:

the WPC base material is used as a bottom plate, the XPE film is used as a surface material, the hot melt adhesive obtained in the embodiments 1-4 and the comparative examples 1 and 2 is respectively coated on the WPC bottom plate after being melted at 120 ℃, and the coating weight is 50g/m²Immediately applying and pressing XPE surface material with the width of 25mmThe 90 ° peel force after 5min was measured, and the results are shown in table 3.

2) Open time test method:

referring to the standard GB/T13477.5-2002, after the reactive hot melt adhesives obtained in examples 1-4 and comparative examples 1 and 2 of the present invention are respectively heated to 120 ℃ for melting, a layer of adhesive with the thickness of 0.1 mm is quickly scraped out by a mold and coated on a smooth flat plate, and the time from the coating start to the non-adhesion of the surface of the hot melt adhesive is recorded, and the results are shown in Table 3.

TABLE 3 comparison table of initial tack and open time properties of the reactive hot melt adhesives obtained in examples 1 to 4 of the present invention and comparative examples 1 and 2

As can be seen from Table 3, the hot melt adhesives obtained in the examples 1-4 of the present invention all have good initial adhesion and long open time, while the initial adhesion of the comparative example 1 is relatively small although the open time is long, and the initial adhesion of the comparative example 2 is greatly improved but the open time is greatly reduced after the high glass transition temperature amorphous resin is added to the formula. Therefore, the conventional polyether and polyester polyol are used as raw materials to prepare the hot melt adhesive, so that the high initial adhesion and the long opening time are hardly realized at the same time, and the hot melt adhesive prepared by using the polyether ester multi-block copolymerized dihydric alcohol as a main raw material has the performances of high initial adhesion and long opening time.