CN114262952B - A kind of composite material and its preparation method and application - Google Patents

Abstract

The invention provides a composite material, which is characterized in that it comprises a skin layer and a core layer, the skin layer is composed of component A, and the core layer is composed of component B, wherein, in component A, each component by weight In terms of parts, it includes: 10-60 parts of polyhydroxyalkanoate and 0.1-2 parts of nucleating agent; in component B, each component includes: 80-95 parts of nylon and 5-20 parts of PHA. Component A has the advantages of being dyeable and fully biodegradable, and Component B has the advantages of high toughness and high strength. The two are made into composite filaments with a skin-core structure, which solves the problems of low toughness and nylon materials in existing PHA materials. Difficult problem. The composite material provided by the invention can be continuously spun into yarns and used as textile materials, and the prepared textiles have excellent softness and strength.

Description

A kind of composite material and its preparation method and application

technical field

The invention belongs to the technical field of composite materials, and in particular relates to a composite material and its preparation method and application.

Background technique

Polyhydroxyalkanoate (referred to as PHA) is a kind of thermoplastic aliphatic biopolyester synthesized by prokaryotic microorganisms as carbon source and energy storage under the condition of carbon and nitrogen nutrition imbalance. The mechanical properties of PHA are similar to some thermoplastic materials such as polyethylene and polypropylene. Like general aliphatic polyesters, PHA materials also have many disadvantages in processing and performance, such as relatively narrow processing window, difficult processing and molding, long molding cycle, poor resilience, and high production costs.

Therefore, experts and scholars at home and abroad have carried out modification research on PHA, such as biological modification, chemical modification and physical modification, in order to improve performance, reduce production costs, and promote applications. The biological modification of PHA is to introduce other functional hydroxy fatty acid chain unit into the PHA molecular chain through microbial fermentation under different carbon sources and different fermentation conditions, so as to achieve the purpose of improving the performance of PHA. In the chemical modification of PHA, grafting and block are the most common methods. For example, the thermal stability of PHA can be improved by grafting maleic anhydride (MA). In addition, physical modification is also a common method for PHA modification. For example, blending PHA with polyethylene oxide (PEO) can improve the brittleness of PHA and improve the impact strength of the blended material; blending PHA with polybutylene succinate (PBS) can improve the tensile strength and impact strength of the material. Toughness, the elongation at break can reach 400%; PHA and polylactic acid (PLA) are blended to increase the breaking strength.

At present, how to improve the defects in the performance of PHA materials, especially the mechanical properties such as toughness, is still the subject of most scholars' research.

Contents of the invention

In order to overcome the defects of the above-mentioned prior art, the present invention proposes a composite material and its preparation method and application, which solves the low toughness and low strength of existing polyhydroxyalkanoate products, and the difficulty of degradation of nylon (abbreviated as PA) The problem.

Specifically, it is realized through the following technical solutions:

A composite material, characterized in that it comprises a skin layer and a core layer, the skin layer is composed of component A, and the core layer is composed of component B, wherein,

In component A, each component includes by weight:

Polyhydroxyalkanoate 10-60 parts

Nucleating agent 0.1～2 parts

In component B, each component includes by weight:

Nylon 80～95 parts

5-20 parts of polyhydroxyalkanoate.

Preferably, the nylon is PA6 and PA66.

Component A has the characteristics of being dyeable and fully biodegradable. Component A is used as the skin layer to facilitate the dyeing of textiles when the composite material is used in textiles. Component B is located in the core layer and helps the composite material to degrade. , because most of the degradation of the material is disintegrated from the outside to the inside, disintegrated into small fragments (oligomers), and then further degraded. In addition, component B can provide sufficient toughness and toughness for the overall composite material. strength;

Further, the weight ratio of the component A to the component B is (10-60): (40-90).

Preferably, the polyhydroxyalkanoate has a water content of not more than 30 ppm. Specifically, the water content of the polyhydroxyalkanoate can be controlled below 30ppm by putting the polyhydroxyalkanoate in a drying device for 8-10 hours and drying at a drying temperature of 70-80°C. If the water content is higher than 30ppm, it will have an impact on the stability of processing, because high water content may cause PHA to decompose during extrusion, melting and high temperature processing, resulting in a decrease in the molecular weight of the material, thereby making the thickness of the composite material uneven. Filaments are prone to breakage during spinning, which affects spinnability, or the final spun filaments are more likely to break, which affects the breaking strength of the filaments.

Further, in the polyhydroxyalkanoate, the molar content of 4-hydroxybutyric acid is 7-25%. As the content of 4-hydroxybutyric acid increases, the material will change from brittle to tough, making the toughness better; but if the content of 4-hydroxybutyric acid is less than 7%, the material is relatively brittle and has low toughness; 4 If the content of -hydroxybutyric acid is higher than 25%, the processing temperature will decrease with the increase of the content, the processing window will be narrowed, and the decomposition temperature will also decrease, making the material easy to decompose.

Further, the weight average molecular weight of the polyhydroxyalkanoate is 100,000-800,000, the melting point of the polyhydroxyalkanoate is 100-160°C, and the melt flow index of the polyhydroxyalkanoate is 5-7g /10min. The weight-average molecular weight of polyhydroxyalkanoate is large, which can increase the melting point of polyhydroxyalkanoate; the melt flow index of polyhydroxyalkanoate is 5-7g/10min, which can make the masterbatch have a better melt index. It has good fluidity and is easy to extrude, ensuring that component A and component B have a good melt extrusion effect when extruded in a composite spinning machine.

Further, the weight average molecular weight of the nylon is 16000-24000, the melting point of the nylon is 200°C-260°C, and the melt flow index of the nylon is 15-50g/10min. Preferably, the nylon is nylon 6 or nylon 66.

Preferably, the nucleating agent is sodium benzoate or p-tert-butylbenzoic acid or uracil carboxylic acid. Nucleating agents can increase the rate of crystallization of polyhydroxyalkanoate powders. When polyhydroxyalkanoate is processed at high temperature, the crystallization speed is slow, and the filaments are easy to stick when forming, and the finished silk after processing becomes brittle when it crystallizes after cooling; adding a nucleating agent makes polyhydroxyalkanoate It can also crystallize quickly under processing, so that the material is not easy to stick, more stable during spinning, and also reduces post-crystallization. The finished product is not easy to become brittle when stored, and the toughness of the material is enhanced.

The present invention also provides the preparation method of above-mentioned composite material, comprises the following steps:

S1: Weigh each component of component A, after mixing and drying, melt, extrude, cool, pelletize and dry through the first extruder to obtain component A;

S2: Weigh each component of component B, after mixing, melt, extrude, cool, pelletize and dry through the second extruder to obtain component B;

S3: Input component A and component B from different feeding ports of the composite spinning machine, perform skin-core composite spinning, and then cool and draw to obtain a composite material.

Further, the melting temperature of the first extruder is 160°C to 180°C, if the melting temperature is lower than 150°C, the polyhydroxyalkanoate powder has a high viscosity and it is difficult to feed; if the melting temperature is higher than 180 °C, the polyhydroxyalkanoate powder is prone to degradation. The melting temperature of the second extruder is 220°C-280°C, and the temperature of the composite spinning machine is 220°C-260°C.

The processing melting temperature of nylon is 220-280°C, and the processing temperature range of PHA is lower and narrower than that of nylon, which is 160-180°C. If it is only blended for extrusion processing and then composite spinning, the extrusion temperature must be processed within the processing temperature range of nylon (220-280°C), but processing at this temperature will cause partial thermal decomposition of PHA, resulting in odor and The processing stability will be affected, and the performance of the material will also be greatly affected. Therefore, PHA-nylon composite materials cannot be prepared by conventional methods, but must be made into a skin-core structure.

Compared with direct blending, the composite spinning sheath-core structure is made. First, PHA and nylon can be extruded in their respective suitable processing temperature ranges to obtain particles; second, spinning through a composite spinning machine to obtain Silk fibers with skin-core structure, the skin and core of the structure can retain the advantages of their respective materials to the greatest extent, the skin has the advantages of being dyeable and fully biodegradable, and the core has the advantages of high toughness and high strength, avoiding direct blending It leads to the mutual influence of the materials between the components, which leads to the fluctuation of the material properties, and the processing stability is also guaranteed; thirdly, if direct blending is used, the difference in the proportion of each component will lead to uneven mixing between the materials, which will affect the processing temperature. In order to improve the performance of composite materials, additional compatibilizers need to be added, and the screening of compatibilizers is difficult.

The present invention also provides the application of the above-mentioned composite material in the preparation of textile products, such as non-woven fabrics and other products.

Compared with the prior art, the present invention has the following advantages:

The composite material provided by the invention has the advantages of degradability and high toughness, and solves the problems of low toughness and difficult degradation of nylon materials existing in existing PHA materials. The composite material provided by the invention can be continuously spun into yarns and used as textile materials, and the manufactured textiles not only have excellent softness, but also have sufficient strength.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings that need to be used in the description of the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present application. For those skilled in the art, other drawings can also be obtained based on these drawings without creative effort.

Fig. 1 is a schematic flow chart of the preparation of the composite material in Example 1 of the present invention.

Detailed ways

The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some, not all, embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

Example 1

A kind of composite material, it is characterized in that, comprises skin layer and core layer, skin layer is made up of component A, and core layer is made up of component B, wherein,

In component A, each component includes by weight:

Polyhydroxyalkanoate 10 parts

Sodium benzoate 0.1 parts

In component B, each component includes by weight:

Nylon 90 parts

Polyhydroxyalkanoate 10 parts.

The weight ratio of component A to component B is 10:40.

The weight-average molecular weight of the polyhydroxyalkanoate is 300,000, the melting point of the polyhydroxyalkanoate is 140° C., and the melt flow index of the polyhydroxyalkanoate is 5 g/10 min. In polyhydroxyalkanoate, the molar content of 4-hydroxybutyric acid is 7%.

The weight average molecular weight of nylon is 16000, the melting point is 200°C, and the melt flow index of nylon is 15g/10min.

Referring to Fig. 1, Fig. 1 is a schematic diagram of the preparation process of the composite material of this embodiment.

The preparation method of the present embodiment is as follows:

S1-1: Weigh 10 parts of polyhydroxyalkanoate powder, wherein the molar content of 4-hydroxybutyric acid in the polyhydroxyalkanoate powder is 7%;

S1-2: Put the polyhydroxyalkanoate powder in a vacuum drum drying equipment for 8 hours and dry at 70°C, and control the water content of the polyhydroxyalkanoate powder below 30PPM;

S1-3: Mix polyhydroxyalkanoate powder and 0.1 part of nucleating agent evenly, melt and extrude through the first twin-screw extruder at 160-180°C, water-cool and pelletize, dry, and make component A;

S2-1: Weigh 90 parts of nylon 6, and weigh 10 parts of polyhydroxyalkanoate powder according to weight, wherein the molar content of 4HB in the polyhydroxyalkanoate powder is 7%;

S2-2: Put the polyhydroxyalkanoate powder in a vacuum drum drying equipment for drying for 8 hours, set the drying temperature to 70°C, and control the water content of the polyhydroxyalkanoate powder below 30PPM;

S2-3: Mix polyhydroxyalkanoate powder and nylon granules evenly, melt and extrude through the second twin-screw extruder at 220-280°C, water-cool and pelletize, and dry to make component B;

S3-1: According to the weight ratio, put component A into the screw 1 of the twin-screw extruder, and melt and extrude it at 160-180°C;

S3-2: According to the weight ratio, put component B into the screw 2 of the twin-screw extruder, and melt and extrude it at 220-280°C;

S3-3: The melted materials A and B enter the sheath-core composite spinning assembly respectively, and are metered and extruded at 220-260°C to form as-spun filaments of composite materials, which are then cooled and drawn to obtain composite materials.

Example 2

A kind of composite material, it is characterized in that, comprises skin layer and core layer, skin layer is made up of component A, and core layer is made up of component B, wherein,

In component A, each component includes by weight:

Polyhydroxyalkanoate 30 parts

1 part p-tert-butylbenzoic acid

In component B, each component includes by weight:

Nylon 80 parts

Polyhydroxyalkanoate 5 parts.

The weight ratio of component A to component B is 10:90.

The weight-average molecular weight of the polyhydroxyalkanoate is 100,000, the melting point of the polyhydroxyalkanoate is 100° C., and the melt flow index of the polyhydroxyalkanoate is 7 g/10 min. In the polyhydroxyalkanoate, the molar content of 4-hydroxybutyric acid was 18%.

The weight average molecular weight of nylon is 24000, the melting point is 260°C, and the melt flow index of nylon is 50g/10min.

The preparation method of the present embodiment is as follows:

S1-1: Weigh 30 parts of polyhydroxyalkanoate powder, wherein the molar content of 4-hydroxybutyric acid in polyhydroxyalkanoate powder is 18%;

S1-2: Put the polyhydroxyalkanoate powder into the vacuum drum drying equipment and dry for 9 hours, the drying temperature is set at 70°C, and the water content of the polyhydroxyalkanoate powder is controlled below 30PPM;

S1-3: Mix polyhydroxyalkanoate powder and 1 part of p-tert-butylbenzoic acid evenly, melt and extrude through the first twin-screw extruder at 160-180°C, water-cool and pelletize, dry, and make a composition Point A;

S2-1: Weigh 80 parts of nylon 66 particles and 5 parts of polyhydroxyalkanoate powder, wherein the molar content of 4HB in the polyhydroxyalkanoate powder is 18%;

S2-2: Put the polyhydroxyalkanoate powder in a vacuum drum drying equipment for drying for 9 hours, set the drying temperature to 70°C, and control the water content of the polyhydroxyalkanoate powder below 30PPM;

S2-3: Mix polyhydroxyalkanoate powder and nylon granules evenly, melt and extrude through the second twin-screw extruder at 220-280°C, water-cool and pelletize, and dry to make component B;

S3-1: According to the weight ratio, put component A into the screw 1 of the twin-screw extruder, and melt and extrude it at 160-180°C;

S3-2: According to the weight ratio, put component B into the screw 2 of the twin-screw extruder, and melt and extrude it at 220-280°C;

S3-3: The melted materials A and B enter the sheath-core composite spinning assembly respectively, and are metered and extruded at 220-260°C to form as-spun filaments of composite materials, which are then cooled and drawn to obtain composite materials.

Example 3

A kind of composite material, it is characterized in that, comprises skin layer and core layer, skin layer is made up of component A, and core layer is made up of component B, wherein,

In component A, each component includes by weight:

Polyhydroxyalkanoate 50 parts

Uracil carboxylic acid 0.5 parts

In component B, each component includes by weight:

Nylon 85 parts

Polyhydroxyalkanoate 10 parts.

The weight ratio of component A to component B is 60:40.

The weight-average molecular weight of the polyhydroxyalkanoate is 800,000, the melting point of the polyhydroxyalkanoate is 160°C, and the melt flow index of the polyhydroxyalkanoate is 7g/10min. In the polyhydroxyalkanoate, the molar content of 4-hydroxybutyric acid was 22%.

The weight average molecular weight of nylon is 24000, the melting point is 260°C, and the melt flow index of nylon is 50g/10min.

The preparation method of the present embodiment is as follows:

S1-1: Weigh 50 parts of polyhydroxyalkanoate powder, wherein the molar content of 4-hydroxybutyric acid in polyhydroxyalkanoate powder is 22%;

S1-2: Put the polyhydroxyalkanoate powder in the vacuum drum drying equipment and dry for 8 hours, the drying temperature is set at 80°C, and the water content of the polyhydroxyalkanoate powder is controlled below 30PPM;

S1-3: Mix polyhydroxyalkanoate powder and 0.5 part of uracil carboxylic acid evenly, melt and extrude through the first twin-screw extruder at 160-180°C, water-cool and cut into pellets, and dry to make component A ;

S2-1: Weigh 85 parts of nylon 6 particles and 10 parts of polyhydroxyalkanoate powder, wherein the molar content of 4HB in the polyhydroxyalkanoate powder is 22%;

S2-2: Put the polyhydroxyalkanoate powder in a vacuum drum drying equipment for drying for 8 hours, set the drying temperature to 80°C, and control the water content of the polyhydroxyalkanoate powder below 30PPM;

S2-3: Mix polyhydroxyalkanoate powder and nylon granules evenly, melt and extrude through the second twin-screw extruder at 220-280°C, water-cool and pelletize, and dry to make component B;

S3-1: According to the weight ratio, put component A into the screw 1 of the twin-screw extruder, and melt and extrude it at 160-180°C;

S3-2: Put the component B into the screw 2 of the twin-screw extruder according to the weight ratio, and melt and extrude it at 220-280°C;

S3-3: The melted materials A and B enter the sheath-core composite spinning assembly respectively, and are metered and extruded at 220-260°C to form as-spun filaments of composite materials, which are then cooled and drawn to obtain composite materials.

Example 4

A kind of composite material, it is characterized in that, comprises skin layer and core layer, skin layer is made up of component A, and core layer is made up of component B, wherein,

In component A, each component includes by weight:

Polyhydroxyalkanoate 60 parts

Sodium Benzoate 2 parts

In component B, each component includes by weight:

Nylon 95 parts

Polyhydroxyalkanoate 5 parts.

The weight ratio of component A to component B is 60:90.

The weight-average molecular weight of the polyhydroxyalkanoate is 500,000, the melting point of the polyhydroxyalkanoate is 150°C, and the melt flow index of the polyhydroxyalkanoate is 6g/10min. In the polyhydroxyalkanoate, the molar content of 4-hydroxybutyric acid is 25%.

The weight average molecular weight of nylon is 16000-24000, the melting point is 200°C-260°C, and the melt flow index of nylon is 15-50g/10min.

The preparation method of the present embodiment is as follows:

S1-1: Weigh 60 parts of polyhydroxyalkanoate powder, wherein the molar content of 4-hydroxybutyric acid in polyhydroxyalkanoate powder is 25%;

S1-2: Put the polyhydroxyalkanoate powder in a vacuum drum drying equipment for 8 hours and dry at 70°C, and control the water content of the polyhydroxyalkanoate powder below 30PPM;

S1-3: Mix polyhydroxyalkanoate powder and 2 parts of sodium benzoate evenly, melt and extrude through the first twin-screw extruder at 160-180°C, water-cool and pelletize, and dry to prepare component A;

S2-1: Weigh 95 parts of nylon 66 particles and 5 parts of polyhydroxyalkanoate powder, wherein the molar content of 4HB in the polyhydroxyalkanoate powder is 25%;

S2-2: Put the polyhydroxyalkanoate powder in a vacuum drum drying equipment for drying for 8 hours, set the drying temperature to 70°C, and control the water content of the polyhydroxyalkanoate powder below 30PPM;

S2-3: Mix polyhydroxyalkanoate powder and nylon granules evenly, melt and extrude through the second twin-screw extruder at 220-280°C, water-cool and pelletize, and dry to make component B;

S3-1: According to the weight ratio, put component A into the screw 1 of the twin-screw extruder, and melt and extrude it at 160-180°C;

S3-2: According to the weight ratio, put component B into the screw 2 of the twin-screw extruder, and melt and extrude it at 220-280°C;

S3-3: The melted materials A and B enter the sheath-core composite spinning assembly respectively, and are metered and extruded at 220-260°C to form as-spun filaments of composite materials, which are then cooled and drawn to obtain composite materials.

Comparative example 1

In this Comparative Example 1, the water content of the polyhydroxyalkanoate powder was 35PPM, and the rest were consistent with Example 1.

Comparative example 2

In this comparative example, the weight ratio of component A and component B is 70:30, and the rest are consistent with Example 1.

The composite materials prepared in Examples and Comparative Examples were tested for performance, and the results are shown in Table 1.

As can be seen from the data of Examples and Comparative Examples, because the water content of polyhydroxyalkanoate and the proportioning of Component A and Component B in the composite material are not suitable, the breaking strength, elongation at break and fracture of Comparative Examples The work average is worse than that of the examples, indicating that the material strength of the comparative examples is far less than that of the examples.

Example 5

The composite material prepared in Example 1 of the present invention is used to prepare non-woven fabric, and the performance test of the prepared non-woven fabric is carried out. The thermal softening temperature measured is 90° C., the breaking strength is 3.86 cN/dtex, and the breaking elongation is 39.62%, and the work of fracture is 60.12 N.cm. It can be seen that the composite material provided by the present invention can be applied to textiles with higher performance requirements such as strength.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included in the protection of the present invention. within range.

Claims (6)

1. A composite material, characterized in that, comprises a skin layer and a core layer, the skin layer is made up of component A, and the core layer is made up of component B, wherein, In component A, each component is by weight, is composed of: Polyhydroxyalkanoate 10-60 parts Nucleating agent 0.1～2 parts In component B, each component is by weight, and consists of: Nylon 80～95 parts 5-20 parts of polyhydroxyalkanoate; The water content of the polyhydroxyalkanoate is not more than 30ppm; The weight ratio of the component A to the component B is (10-60): (40-90); In the polyhydroxyalkanoate, the molar content of 4-hydroxybutyric acid is 7-25%; The weight average molecular weight of the polyhydroxyalkanoate is 100000-800000, and the melt flow index of the polyhydroxyalkanoate is 5-7g/10min. 2. The composite material according to claim 1, characterized in that, the weight average molecular weight of the nylon is 16000-24000, and the melt flow index of the nylon is 15-50 g/10min. 3. composite material according to claim 1, is characterized in that, nucleating agent is sodium benzoate or p-tert-butylbenzoic acid or uracil carboxylic acid. 4. A method for preparing the composite material according to any one of claims 1-3, characterized in that, comprising the following steps: S1: Weigh each component of component A, after mixing and drying, melt, extrude, cool, pelletize and dry through the first extruder to obtain component A; S2: Weigh each component of component B, after mixing, melt, extrude, cool, pelletize and dry through the second extruder to obtain component B; S3: Input component A and component B from different feeding ports of the composite spinning machine, perform skin-core composite spinning, and then cool and draw to obtain a composite material. 5. The preparation method of the composite material according to claim 4, characterized in that, the melting temperature of the first extruder is 160°C to 180°C, and the melting temperature of the second extruder is 220°C to 280°C, the temperature of the composite spinning machine is 220°C to 260°C. 6. The application of the composite material according to any one of claims 1-3 in the preparation of textile products.

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