阅读说明：本技术 一种基于生物基改性透明聚酰胺聚合物及纤维的制备方法 (Preparation method of bio-based modified transparent polyamide polymer and fiber ) 是由 郝超伟 来国桥 李泽 马清芳 潘庆华 于 2020-08-26 设计创作，主要内容包括：本发明涉及生物可降解高分子材料技术领域,为了提高聚酰胺材料及其纤维的透明度问题,本发明提出一种基于生物基改性透明聚酰胺聚合物及纤维的制备方法,通过化学方法,利用生物基改性剂呋喃二羧酸及其衍生物和透明剂与环基二胺聚合,并在一定的凝固条件下得到透明性聚酰胺,透明度为88-98%,结晶度≤15%,与传统的通过物理共混、化学共聚方法制备透明聚酰胺有所区别。制备出生物基透明聚酰胺并通过纺丝工艺调控制备出生物基改性透明聚酰胺纤维,断裂强度为4.0～8.0cN/dtex,条干不匀率为1.5～2.0,断裂伸长率为10～30%,可用于渔网、钓鱼线等,使聚酰胺的应用领域得到极大地拓展和延伸。(The invention relates to the technical field of biodegradable high polymer materials, and provides a preparation method of a bio-based modified transparent polyamide polymer and a fiber based on the bio-based modified transparent polyamide polymer, which aims to improve the transparency of polyamide materials and fibers thereof, wherein a bio-based modifier furan dicarboxylic acid and derivatives thereof, and a transparentizing agent are polymerized with cyclic diamine through a chemical method, and transparent polyamide is obtained under certain solidification conditions, wherein the transparency is 88-98%, the crystallinity is less than or equal to 15%, and the method is different from the traditional method for preparing transparent polyamide through physical blending and chemical copolymerization. The bio-based transparent polyamide is prepared, the bio-based modified transparent polyamide fiber is prepared by regulating and controlling a spinning process, the breaking strength is 4.0-8.0 cN/dtex, the yarn evenness is 1.5-2.0, and the elongation at break is 10-30%, so that the bio-based modified transparent polyamide fiber can be used for fishing nets, fishing lines and the like, and the application field of the polyamide is greatly expanded and extended.)

1. A preparation method of a bio-based modified transparent polyamide polymer is characterized by comprising the following steps:

(1) purifying furan dicarboxylic acid and derivatives thereof, diamine compound and a transparent agent, and drying;

(2) adding furan dicarboxylic acid and derivatives thereof and a diamine compound into a reaction kettle, adding a transparent agent and an antioxidant, replacing air in the kettle with inert gas for several times, pressurizing to 0.11-0.3MPa, heating while stirring, carrying out pre-polycondensation reaction, then firstly releasing gas to normal pressure, then heating to continue polycondensation reaction until the reaction is finished, discharging under the pressure of 0.2-0.5MPa, cooling and pelletizing to obtain the bio-based modified transparent polyamide polymer.

2. The method for preparing bio-based modified transparent polyamide polymer according to claim 1, wherein the furan dicarboxylic acid and its derivatives are selected from one or more of furan-2, 5-dicarboxylic acid, furan 3, 4-dicarboxylic acid, furan-2, 5-diacetic acid, furan 3, 4-diacetic acid, furan-2, 5-furylidene di (methylene) diacetic acid, furan-3, 4-furylidene di (methylene) diacetic acid, furan-2, 5-dicarboxylic chloride, furan-3, 4-dicarboxylic chloride, etc.; the diamine compound is selected from aromatic diamine, and the transparent agent is one or more of metal stearate, isophthalic acid, metal chloride and aromatic diamide compounds.

3. The preparation method based on bio-based modified transparent polyamide polymer according to claim 1 or 2, characterized in that the molar ratio of carboxylic acid groups to amine groups in step (2) is 0.7-1.3: 1.

4. the method for preparing the bio-based modified transparent polyamide polymer according to claim 1 or 2, wherein the adding amount of the transparent agent is 2-8 mol% of the carboxylic acid group, and the adding amount of the antioxidant is 0.1-1.0wt% of the total adding mass of the carboxylic acid and the diamine.

5. The method for preparing bio-based modified transparent polyamide polymer as claimed in claim 1, wherein the pre-polycondensation temperature in step (2) is 200-230 ℃, the pre-polycondensation pressure is 1.2-2.0MPa, and the pre-polycondensation time is 1.5-3 h; the polycondensation reaction temperature is 240 ℃ and 270 ℃, and the reaction time is 1.5-3 h.

6. The preparation method based on bio-based modified transparent polyamide polymer as claimed in claim 1, wherein step (2) is cooled by a coagulating bath, the transparency of the polyamide is 88-98%, and the crystallinity is less than or equal to 15%.

7. A method for preparing bio-based modified transparent polyamide fiber by using bio-based modified transparent polyamide polymer obtained by the method for preparing bio-based modified transparent polyamide polymer according to any one of claims 1 to 6, wherein the method comprises the following steps: the bio-based modified transparent polyamide polymer is dried and then placed in a melt spinning machine, and is subjected to screw melting, spinning manifold, spinning assembly, cooling, oiling, drafting, winding and other processes to prepare the bio-based modified transparent polyamide fiber.

8. The method for preparing the bio-based modified transparent polyamide fiber according to claim 7, wherein the drying is carried out at 80-110 ℃ for 12-24 h.

9. The method for preparing the bio-based modified transparent polyamide fiber as claimed in claim 7, wherein the screw melting temperature is 220-.

10. The method for preparing the bio-based modified transparent polyamide fiber according to claim 7, wherein the prepared bio-based modified transparent polyamide fiber has a single filament fineness of 2.0dtex to 16.0dtex, a breaking strength of 4.0 cN/dtex to 8.0cN/dtex, a yarn unevenness of 1.5 to 2.0 and an elongation at break of 10 to 30%.

Technical Field

The invention relates to the technical field of biodegradable high polymer materials, in particular to a preparation method of a bio-based modified transparent polyamide polymer and fiber.

Background

Since the last century, a large number of synthetic polymer products are manufactured in large scale successively, which greatly enriches our production and life, but the vast majority of the synthetic polymer materials are non-degradable materials, which brings serious white pollution and greenhouse effect, and consequently, the physical and mental health of human beings is greatly influenced. The problem of developing biodegradable materials to reduce the "greenhouse effect" is therefore at hand. Nylon is an important engineering plastic variety at present. Ordinary nylon is a crystalline polymer, and the product is milky white. The transparent nylon is amorphous or microcrystalline thermoplastic nylon, has light transmittance of more than 90 percent, is superior to Polycarbonate (PC) and polymethyl methacrylate (PMMA) in environmental stress cracking resistance, can be used for packaging beverages and foods, can also be used as a packaging material for precision instruments, instruments and pharmaceutical chemicals, and can be used for producing damp-proof and shock-absorbing cushions, foaming plates and the like. And the wear resistance, flexibility, density and the like of the material are better than those of the traditional transparent material, and the material can produce more flexible products and lighter sports glasses, sunglasses and the like. What's more, the spinnability of the transparent nylon makes it have important application foreground in fiber and textile fields, especially fishing net weaving, etc. while other transparent materials, such as PMMA and PC, do not have the function. According to statistics, 38% of the Polyamide (PA) material yield is used in the fiber field, 46% in the injection molding field, 14% in the extrusion molding field, and the rest of the deep-processed products only account for about 2%. The PA fiber (mainly comprising PA6 and PA 66) is the second largest synthetic fiber variety next to polyester fiber, and the yield of the polyamide fiber in China reaches 400 million tons in 2019. The production of transparent fibers has also increased year by year.

However, the continuously strengthened ecological consciousness is becoming the core criteria of the continuous development of enterprises, the processing technology of bio-based PA materials and products thereof is getting more and more attention from the chemical fiber industry, the research and development of bio-based PA6, PA66 and long-chain PA varieties are also being actively carried out, lysine and adipic acid are obtained by fermentation based on biomass glucose at present as raw materials for synthesizing PA6 and PA66, diamine and diacid are prepared from castor oil, and thus PA products such as PA11, PA12, PA610 and PA1010 are obtained. Among them, Rennovia company in the United states judges that the global yield of bio-based PA fiber will break through 100 million tons in 2022 based on the current supply situation of global glucose raw materials and the commercial reality of technologies for preparing bio-based hexamethylene diamine and adipic acid by chemical catalysis technology.

With the rapid increase of fisheries and fishing enthusiasts, the output of PA6 and PA66 monofilaments, which are mainly used for weaving fishing nets and fishing lines, is also increasing year by year. The clarity of the monofilaments has a critical effect on the effectiveness of catching fish and shrimp. Meanwhile, the 'waste' of fishing nets and fishing lines generated every year also has serious influence on the ecological environment and aquatic organisms, and the development of a preparation technology of biodegradable and transparent polyamide material and fiber is urgent.

Disclosure of Invention

In order to solve the problem that 'waste' of a fishing net causes serious influence on ecological environment and aquatic organisms, the invention provides a preparation method based on a bio-based modified transparent polyamide polymer and a bio-based modified transparent polyamide fiber, the bio-based transparent polyamide is prepared, the bio-based modified transparent polyamide fiber is prepared by regulating and controlling a spinning process, and the bio-based modified transparent polyamide fiber can be used for fishing nets, fishing lines and the like, so that the application field of polyamide is greatly expanded and extended.

The invention is realized by the following technical scheme: the preparation method of the bio-based modified transparent polyamide polymer comprises the following steps:

(1) purifying furan dicarboxylic acid and derivatives thereof, diamine compound and a transparent agent, and drying;

the furan dicarboxylic acid and the derivatives thereof are selected from one or more of furan-2, 5-dicarboxylic acid, furan 3, 4-dicarboxylic acid, furan-2, 5-diacetic acid, furan 3, 4-diacetic acid, furan-2, 5-furylidene di (methylene) diacetic acid, furan-3, 4-furylidene di (methylene) diacetic acid, furan-2, 5-diformyl chloride, furan-3, 4-diformyl chloride and the like;

the diamine compound is selected from aromatic diamine, preferably one or more of p-phenylenediamine, m-phenylenediamine, o-phenylenediamine, cyclohexyl-1, 4-diamine, furan-2, 5-diamine and furan-3, 4-diamine.

The transparent agent is selected from one or more of metal stearate, isophthalic acid, metal chloride and aromatic diamide compounds.

The furan dicarboxylic acid (FDCA) is a biological-based chemical prepared by using biomass as a raw material through a chemical or biological method, has good biodegradability, less carbon atom number than benzene ring and weaker aromaticity than benzene ring, and the FDCA-based polymer has better thermodynamic and mechanical properties than a phthalic acid/phthalic acid polymer.

The drying method is drying at 50 deg.C for 2-8h, preferably vacuum drying.

(2) Adding furan dicarboxylic acid and derivatives thereof and a diamine compound into a reaction kettle, adding a transparent agent and an antioxidant, replacing air in the kettle with inert gas for several times, pressurizing to 0.11-0.3MPa, heating while stirring, carrying out a pre-polycondensation reaction, then discharging gas to normal pressure, heating to continue the polycondensation reaction until the reaction is finished, discharging under the pressure of 0.2-0.5MPa, cooling, and pelletizing to obtain the bio-based modified transparent polyamide polymer.

The addition amount of the furan dicarboxylic acid and the derivatives thereof and the diamine compound is that the molar ratio of the carboxylic acid groups to the amino groups is 0.7-1.3: 1, preferably 0.9 to 1.10, and more preferably 0.95 to 1.05.

The amount of added clearing agent is 2-8 mol% (based on 100% carboxylic acid groups) in order to improve the transparency of the PA material and also of the fibres.

The antioxidant is a commercial product, and the addition amount is 0.1-1.0wt% (based on the total mass of the added carboxylic acid and diamine).

The pre-polycondensation temperature is 200-;

the polycondensation reaction is carried out at normal pressure and at the temperature of 240 ℃ and 270 ℃ for 1.5-3 h;

preferably, the cooling is performed by a coagulation bath, which is a liquid bath that is water or a 10% aqueous solution of NaOH by mass.

The common PA material is easy to crystallize to form a crystalline polymer due to the polarity and intermolecular hydrogen bond action, and the product is milky. In order to obtain transparency, it is necessary to suppress the formation of crystals and to form an amorphous or low-crystalline polymer. The invention mainly uses a chemical method, utilizes the biological-based modifier furan dicarboxylic acid and derivatives thereof and a transparent agent to polymerize with cyclic diamine, and obtains transparent polyamide under certain solidification conditions, which is different from the traditional method for preparing transparent polyamide by physical blending and chemical copolymerization. The transparency of the obtained modified transparent polyamide based on the bio-based is 88-98%, and the crystallinity is less than or equal to 15%. Meanwhile, the transparent fiber is spun by a spinning process, can be used in the fields of fishing nets, fishing lines and the like, and greatly expands and extends the application field of polyamide.

A method for preparing a bio-based modified transparent polyamide fiber by using the bio-based modified transparent polyamide polymer comprises the following steps: the bio-based modified transparent polyamide polymer is dried and then placed in a melt spinning machine, and is subjected to screw melting, spinning manifold, spinning assembly, cooling, oiling, drafting, winding and other processes to prepare the bio-based modified transparent polyamide fiber.

The drying is carried out for 12-24 h at the temperature of 80-110 ℃.

The melting temperature of the screw is 220-290 ℃, preferably 240-280 ℃, and more preferably 255-270 ℃; the temperature of a spinning box body is 250-270 ℃, a circular blowing cooling mode is adopted, the drafting is the drafting between a first hot roller and a second hot roller, the drafting ratio is 1.6-3.0, preferably 1.8-2.6, and more preferably 2.0-2.4; the spinning speed is 2000-6000 m/min, preferably 3500-4800 m/min, and more preferably 4200-4500 m/min.

In order to avoid uneven cooling of the strand silk, a circular blowing cooling mode is adopted, the temperature of cooling air is 20 +/-2 ℃, the humidity is 50 +/-10%, and the air speed is 0.7 +/-0.1 m/s.

The monofilament titer of the prepared bio-based modified transparent polyamide fiber is 2.0dtex to 16.0dtex, preferably 4.0dtex to 12.0dtex, and more preferably 5.0dtex to 10.0 dtex; the breaking strength of the fiber is 4.0-8.0 cN/dtex, preferably 4.8-7.0 cN/dtex, more preferably 5.8-6.8 cN/dtex; the yarn evenness unevenness is 1.5-2.0, and the elongation at break is 10-30%.

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

(1) the polyamide prepared by the method has obviously improved transparency, and the transparent fiber is prepared by regulating and controlling the spinning process;

(2) the prepared polyamide and fiber have important significance for environmental protection and relieving the problem of fossil resource consumption.

Detailed Description

The present invention is further illustrated by the following examples, it should be understood that the practice of the invention is not limited to the following examples, and any variations and/or modifications made thereto are intended to fall within the scope of the invention. In the present invention, all the equipment, materials and the like are commercially available or commonly used in the industry, if not specified. The methods in the following examples are conventional in the art unless otherwise specified.

Example 1

Firstly, 0.2mol of p-phenylenediamine, 0.18mol of furan-2, 5-dicarboxylic acid and 0.015mol of isophthalic acid as a clearing agent are weighed according to the mass, respectively purified and dried for 8 hours in vacuum at 50 ℃. Then adding the mixture into a high-pressure reaction kettle, adding one thousandth of composite antioxidant 168/1010 in mass ratio, and fully stirring a plurality of monomers and antioxidants to uniformly disperse the monomers and the antioxidants. And (3) sealing the high-pressure reaction kettle, vacuumizing for many times until the air in the kettle is exhausted, and then filling inert gas to ensure that the pressure in the kettle reaches about 0.2 MPa. Slowly and sectionally heating the temperature in the polymerization kettle to 230 ℃, and slowly deflating when the pressure in the polymerization kettle reaches 1.6MPa, so that the pressure in the kettle is always kept at about 1.6MPa, and the pressure and heat preservation time is 90 DEGAnd (3) minutes. Then slowly deflating to normal pressure, controlling the deflating time at 60 minutes, keeping the system at normal pressure for 90 minutes, and controlling the central temperature at 260 ℃. Finally preheating the discharge port and charging N₂And (3) opening a discharge port valve under the pressure of 0.5MPa, allowing the material to flow out through a discharge port, cooling in a water bath, and granulating to obtain the bio-based modified transparent polyamide 1.

The transparency of the bio-based modified transparent polyamide 1 is 93 percent and the crystallinity of the bio-based modified transparent polyamide is 14 percent.

Preparation example 1

The bio-based modified transparent polyamide 1 prepared in example 1 is dried at 100 ℃ for 8h and then placed in a melt spinning machine, and is subjected to screw melting, spinning beam, spinning assembly, cooling, oiling, drafting, winding and other processes to prepare the bio-based modified transparent polyamide fiber 1. Wherein the melting temperature of the screw is 278 ℃, the temperature of the spinning box body is 270 ℃, the temperature of cooling air of circular blowing is 22 ℃, the humidity is 50 percent, the wind speed is 0.6m/s, the drafting ratio between the first hot roller and the second hot roller is 2.3, and the spinning speed is 4500 m/min.

The testing shows that the single filament number of the prepared bio-based modified transparent polyamide fiber 1 is 4.0dtex, the breaking strength of the fiber is 6.2cN/dtex, the yarn unevenness is 1.8, and the elongation at break is 16%.

Example 2

Firstly, 0.2mol of m-phenylenediamine, 0.20mol of furan-3, 4-dicarboxylic acid and 0.01mol of calcium stearate as a transparent agent are weighed according to the mass, respectively purified and dried for 8 hours in vacuum at 50 ℃. Then adding the mixture into a high-pressure reaction kettle, adding one thousandth of composite antioxidant 168/1010 in mass ratio, and fully stirring a plurality of monomers and antioxidants to uniformly disperse the monomers and the antioxidants. Sealing the high-pressure reaction kettle, vacuumizing for many times until the air in the kettle is exhausted, and then filling inert gas N₂The pressure in the kettle reaches 0.3 MPa. Slowly and sectionally heating the temperature in the polymerization kettle to 220 ℃, and slowly deflating when the pressure in the polymerization kettle reaches 1.6MPa, so that the pressure in the kettle is always kept at about 1.6MPa, and the pressure maintaining and heat preserving time is 100 minutes. Slowly deflating to normal pressure, controlling the deflation time at 70 minutes, and maintaining the system at normal pressure for 120 minutesThe core temperature was controlled at 255 ℃. Finally preheating the discharge port and filling inert gas N₂And opening a discharge port valve under the pressure of 0.5MPa, allowing the material to flow out through a discharge port, and cooling and granulating the material by adopting 10wt% NaOH water bath to obtain the bio-based modified transparent polyamide 2.

The transparency of the bio-based modified transparent polyamide 2 is tested to be 97 percent, and the crystallinity is 7 percent.

Preparation example 2

The bio-based modified transparent polyamide 2 prepared in example 2 is dried at 85 ℃ for 10h and then placed in a melt spinning machine, and is subjected to screw melting, spinning beam, spinning assembly, cooling, oiling, drafting, winding and other processes to prepare the bio-based modified transparent polyamide fiber 2. Wherein the melting temperature of the screw is 267 ℃, the temperature of a spinning box is 267 ℃, the temperature of circular blowing cooling air is 21 ℃, the humidity is 55%, the wind speed is 0.7m/s, the drawing ratio between the first hot roller and the second hot roller is 2.4, and the spinning speed is 4300 m/min.

The testing shows that the single filament number of the prepared bio-based modified transparent polyamide fiber 2 is 6.0dtex, the breaking strength of the fiber is 6.0cN/dtex, the yarn unevenness is 1.9, and the elongation at break is 18%.

Example 3

Firstly, 0.2mol of furan-2, 5 diamine, 0.20mol of furan-2, 5-methylene diacetic acid and 0.005mol of anhydrous calcium chloride are weighed according to the mass, respectively purified, dried in vacuum at 50 ℃ for 4h, added into a high-pressure reaction kettle, and added with one thousandth of composite antioxidant 168/1010 in mass ratio, and a plurality of monomers and antioxidants are fully stirred to be uniformly dispersed. Sealing the high-pressure reaction kettle, vacuumizing for many times until the air in the kettle is exhausted, and then filling inert gas N₂The pressure in the kettle reaches about 0.3 Mpa. Slowly and sectionally heating the temperature in the polymerization kettle to 215 ℃, and slowly deflating when the pressure in the polymerization kettle reaches 1.2MPa, so that the pressure in the kettle is always kept at about 1.2MPa, and the pressure maintaining and heat preserving time is 180 minutes. Then slowly deflating to normal pressure, controlling the deflating time at 60 minutes, keeping the system at the normal pressure for 180 minutes, and controlling the central temperature at 253 ℃. Finally preheating discharge holeIs filled with inert gas N₂And (3) opening a discharge port valve under the pressure of 0.5MPa, allowing the material to flow out through a discharge port, cooling in a water bath, and granulating to obtain the bio-based modified transparent polyamide 3.

The transparency of the bio-based modified transparent polyamide 3 is tested to be 95 percent, and the crystallinity is 10 percent.

Preparation example 3

The bio-based modified transparent polyamide 3 prepared in example 3 is dried at 90 ℃ for 8h and then placed in a melt spinning machine, and is subjected to screw melting, spinning beam, spinning assembly, cooling, oiling, drafting, winding and other processes to prepare the bio-based modified transparent polyamide fiber 3. Wherein the melting temperature of the screw is 262 ℃, the temperature of the spinning box is 262 ℃, the temperature of the cooling air of the circular blowing is 21 ℃, the humidity is 60 percent, the wind speed is 0.6m/s, the drafting ratio between the first hot roll and the second hot roll is 2.2, and the spinning speed is 4200 m/min.

The testing shows that the single filament number of the prepared bio-based modified transparent polyamide fiber 3 is 7.0dtex, the breaking strength of the fiber is 5.8cN/dtex, the yarn unevenness is 1.9, and the elongation at break is 20%.

Comparative example

The transparency of the nylon resin used in the current commonly used fishing net is 76-93%, the filament number of the nylon fiber used is 8-30dtex, and the breaking strength is 4.4-7.7 cN/dtex.

The bio-based modified transparent polyamide fiber is prepared by using the bio-based modified transparent polyamide polymer, so that the prepared polyamide has obviously improved transparent performance, reduced filament number and environmental protection significance.

The above-described preferred embodiments are merely illustrative and explanatory of the present invention and are not restrictive of the invention as claimed. Although the present invention has been described in detail by the inventor, it is obvious that various modifications and/or additions can be made to the described embodiments or replacements can be made by those skilled in the art according to the disclosure of the summary of the invention and the embodiments, and the technical effects of the present invention can be achieved, therefore, the detailed description is omitted. The terms appearing in the present invention are used for illustration and understanding of the technical aspects of the present invention, and do not constitute limitations of the present invention.