WO2020098588A1 - Polyphenylene sulfide composite material and preparation method therefor - Google Patents

Abstract

A polyphenylene sulfide composite material and a preparation method therefor. The composite material comprises the following components in mass percentage: 50-98% of a polyphenylene sulfide resin, 0.5-20% of a low molecular weight polymer plasticizer, 0.5-20% of a toughening agent, 0.5-15% of a flame retardant, and 0.05-2% of an anti-dripping agent. By adding the low molecular weight polymer plasticizer to the composite material, the impact resistance of the composite material can be improved, and the processing fluidity of the composite material can also be improved; and a small amount of the flame retardant and anti-dripping agent are added at the same time, so that the flame retardant requirement for the polyphenylene sulfide material can be met.

Description

[Name of invention formulated by ISA according to Rule 37.2] Polyphenylene sulfide composite material and its preparation method Technical field

The invention belongs to the field of polymer material modification, in particular to a high-toughness flame-retardant polyphenylene sulfide composite material and a preparation method thereof.

Background technique

Polyphenylene sulfide is a thermoplastic crystalline polymer with excellent comprehensive properties. It has good moldability, chemical resistance, flame retardancy, rigidity and modulus. It has high dimensional stability, excellent electrical properties, and fatigue resistance. High, good creep resistance, easy to form, and has the characteristics of aging resistance, radiation resistance, non-toxic and so on. It has a wide range of applications in the fields of electronics, automobiles, precision machinery, chemicals, home appliances, and aviation, aerospace, and national defense. In recent years, it has developed into the world's sixth-largest general-purpose engineering plastic.

Polyphenylene sulfide has excellent heat resistance: its melting point exceeds 280 ℃, its heat distortion temperature exceeds 260 ℃, and its long-term use temperature is 220-240 ℃. It degrades in air at 700 ° C and inert gas at 1000 ° C still maintains 40% quality. Short-term heat resistance and thermal stability for long-term continuous use are superior to all current engineering plastics. The flame retardancy of polyphenylene sulfide can reach UL94V-0 level, and the oxygen index (LOI)> 57%. The chemical structure of polyphenylene sulfide itself has good flame retardant properties, so it can be used as a flame retardant material.

Polyphenylene sulfide has a molecular structure with a benzene ring alternately connected to the sulfur atom at the para position, and the molecular chain has great rigidity and regularity. Therefore, polyphenylene sulfide is a crystalline polymer with a crystallinity of up to 70% -80%. It can be seen that although pure polyphenylene sulfide material has high rigidity but poor toughness, it is limited in the application fields where the toughness requirements of products are high. Therefore, the toughening modification of polyphenylene sulfide material is an important means to broaden the application field of the material.

The patent (CN 106243719A) discloses a high toughness polyphenylene sulfide reinforced composite material and its preparation method, the invention can suppress the production of carbides during the preparation process, and improve the compatibility between the resins used, and the invention The prepared polyphenylene sulfide composite material has high impact strength, excellent strength and elongation at the weld line, and high formability.

The patent (CN 106633880A) discloses a high-strength and high-toughness polyphenylene sulfide reinforced composite material and its preparation method. The invention adopts high-tenacity nylon to alloy and toughen polyphenylene sulfide, using two different monofilament diameters Glass fiber compound is used as a reinforcing material. The styrene-maleic anhydride random copolymer is added as a compatibilizer to enhance the interfacial bonding strength of high-toughness nylon and glass fiber and polyphenylene sulfide resin matrix to obtain higher strength. And resilience.

The patent (CN10501050452A) discloses a halogen-free flame-retardant polyphenylene sulfide composite material and a preparation method thereof. The halogen-free flame-retardant polyphenylene sulfide composite material prepared by the invention not only has good impact toughness, but also good Maintain the mechanical strength and processing flow properties of the material.

The polyphenylene sulfide material has good flame retardant properties, so it only needs to add a small amount of flame retardant to achieve a good flame retardant effect, and it also has high rigidity, good dimensional stability, excellent chemical resistance and electrical performance. It can be said that polyphenylene sulfide material has broad application prospects in the flame retardant material market. However, the disadvantages of polyphenylene sulfide's poor toughness limit its application range, and the addition of flame retardants will further reduce the impact resistance of polyphenylene sulfide materials. Traditional toughening methods will reduce polyphenylene sulfide to some extent. The processing flow properties of the material are not conducive to the formation of products with complex structures or thin walls. Therefore, the market urgently needs to develop a polyphenylene sulfide material, which has high flame resistance and high toughness and high fluidity.

Summary of the invention

Problems to be solved by the invention

In order to solve the above problems in the prior art, the present invention provides a high toughness flame retardant polyphenylene sulfide composite material and a preparation method thereof. The invention adopts a compounding method of a toughener and an oligomer plasticizer to improve the toughness of polyphenylene sulfide material and improve the processing fluidity of polyphenylene sulfide material, while adding a small amount of flame retardant and anti-dripping agent to Meet the flame retardant requirements of polyphenylene sulfide materials.

Solutions for solving problems

The invention provides a polyphenylene sulfide composite material, which is characterized by comprising the following components in mass percentage:

Preferably, the following components are included in mass percentage:

Preferably, the polyphenylene sulfide resin is one or a combination of linear polyphenylene sulfide and cross-linked polyphenylene sulfide, wherein the mass flow rate of the linear polyphenylene sulfide melt is 100-400g / 10min ; Mass flow rate of cross-linked polyphenylene sulfide melt is 5-200g / 10min.

Preferably, the low molecular weight polymer plasticizer is selected from one or more of polyester, polyolefin and polyether; preferably, the low molecular weight polyester is an unsaturated polyester, low molecular weight polyolefin It is one or more of low molecular weight polypropylene, low molecular weight polyethylene or low molecular weight polystyrene, and the low molecular weight polyether is polyethylene glycol ether.

Preferably, the low molecular weight polymer plasticizer has a low isotactic structure with an isotacticity of 30% -60%, the weight average molecular weight of the low molecular weight polymer plasticizer is 1000-80000, and the molecular weight distribution is 1-10.

Preferably, the toughener is methyl methacrylate-butadiene-styrene ternary random copolymer, ethylene-methyl acrylate-glycidyl methacrylate ternary random copolymer, maleic anhydride One or a combination of several grafted ethylene-octene copolymers.

Preferably, the flame retardant is a melamine flame retardant, preferably one or a combination of melamine, melamine cyanurate, and melamine phosphate.

Preferably, the anti-dripping agent is polytetrafluoroethylene.

The invention also provides a method for preparing the polyphenylene sulfide composite material according to any one of the above, the method comprises the following steps:

(1) Weigh polyphenylene sulfide resin, low molecular weight polymer plasticizer, toughener, flame retardant, anti-dripping agent according to the mass ratio to obtain a premix, and the low molecular weight polymer plasticizer The weight average molecular weight is 1000-80000, the molecular weight distribution is 1-10, and the isotacticity is 30% -60%;

(2) The obtained premix is added to the extruder, and the mixture extruded from the extruder is cooled and solidified and pelletized to obtain a polyphenylene sulfide composite material.

In addition, the present invention also provides an article comprising the polyphenylene sulfide composite material according to any one of the above items, and the article is selected from a hard hat brim, a coil skeleton, or a button on a safety protective clothing.

Effect of invention

In the present invention, by adding a low molecular weight polymer plasticizer to the composite material, on the one hand, due to the random or syndiotactic molecular chain of the low molecular weight polymer plasticizer entering the polyphenylene sulfide macromolecular chain, it is destroyed The orderly arrangement of molecular chains during the crystallization process of polyphenylene sulfide reduces the crystallinity of polyphenylene sulfide and improves the impact resistance of polyphenylene sulfide; on the other hand, the addition of the low molecular weight polymer plasticizer is weakened The force between the polyphenylene sulfide macromolecular chains has a plasticizing effect, which improves the movement ability of the polyphenylene sulfide macromolecular chains, thereby increasing the fluidity of the polyphenylene sulfide, that is, through the composite material The addition of oligomer plasticizers can improve the impact resistance of composite materials, and also improve the processing fluidity of composite materials.

The low molecular weight polymer plasticizer and the toughening agent (thermoplastic elastomer) in the composite material of the present invention are compounded. After the compounding, a flexible toughening agent toughening system is formed, and both the oligomer plasticizer and the toughening agent There is a synergistic effect between them, which can have a good toughening effect on a rigid and brittle resin matrix such as polyphenylene sulfide, which can toughen the flame retardant polyphenylene sulfide composite material, and the resulting composite material has high impact resistance At the same time, it also has good processing fluidity, and a small amount of flame retardant and anti-drip agent can be added to meet the flame retardant requirements of polyphenylene sulfide materials.

The polyphenylene sulfide composite material of the present invention has excellent flame retardancy, good toughness and molding processing performance, and can be used to prepare hard hats, eaves, coil skeletons, buttons on safety protective clothing and other materials that require flame retardancy Good, toughness and fluidity (thin product thickness is thin) products.

detailed description

First of all, the present invention provides a high toughness flame retardant polyphenylene sulfide composite material, which includes the following components in terms of mass percentage:

In a preferred embodiment, the following components are included in mass percentage:

In a preferred embodiment, the polyphenylene sulfide resin is one or a combination of linear polyphenylene sulfide and cross-linked polyphenylene sulfide, wherein the linear polyphenylene sulfide melt mass flow rate 100-400g / 10min, preferably 200-350g / 10min; cross-linked polyphenylene sulfide melt mass flow rate is 5-200g / 10min, preferably 10-100g / 10min, the weight average molecular weight of the above polyphenylene sulfide The range is 20000-40000, preferably 25000-30000.

In a preferred embodiment, the mass percentage of the polyphenylene sulfide resin is 60-95%, further preferably 70-90%.

In a preferred embodiment, the low molecular weight polymer plasticizer is one or more of ester, olefin or ether low molecular weight polymers. The weight of the low molecular weight polymer plasticizer The average molecular weight is 1000-80000, preferably, the low molecular weight polymer plasticizer has a weight average molecular weight of 10000-80000; further, the low molecular weight polymer of esters, olefins or ethers is an unsaturated polyester , Polypropylene, polyethylene, polyether, polystyrene one or more combinations, preferably one of polyethylene, polypropylene and polystyrene one or more combinations. On the one hand, the random or syndiotactic molecular chain of the low molecular weight polymer plasticizer enters into the polyphenylene sulfide macromolecular chain, which destroys the orderly arrangement of the molecular chain during the crystallization process of the polyphenylene sulfide and reduces the The crystallinity of polyphenylene sulfide improves the impact resistance of polyphenylene sulfide; on the other hand, the addition of the low molecular weight polymer plasticizer weakens the force between the polyphenylene sulfide macromolecular chains and plays a role The effect of plasticization improves the movement ability of polyphenylene sulfide macromolecular chain, thereby increasing the fluidity of polyphenylene sulfide.

In a more preferred embodiment, the mass percentage of the aforementioned low molecular weight polymer plasticizer is 1-15%, preferably 1-10%, more preferably 3-10%.

In a preferred embodiment, the toughening agent is a conventional toughening agent in the art, preferably methyl methacrylate-butadiene-styrene random copolymer (MBS), ethylene-acrylic acid One or more of methyl ester-glycidyl methacrylate ternary random copolymer (EMA), maleic anhydride grafted ethylene-octene copolymer (POE-g-MAH), more preferably, The toughening agent is ethylene-methyl acrylate-glycidyl methacrylate ternary random copolymer (EMA). The molecular weight range of the toughening agent is 1000 to 100,000. The toughening agent is a thermoplastic elastomer, which is mainly composed of a plastic phase and a rubber phase. The plastic phase mainly plays a role of compatibility with the polymer matrix, while the rubber phase It plays the role of absorbing and buffering external impact forces. The toughening agent is compounded with the above oligomer plasticizer to form a flexible toughening agent toughening system. There is a synergistic effect between the two, which is good for a resin matrix such as polyphenylene sulfide with strong rigidity and brittleness. The toughening effect.

In a more preferred embodiment, the mass percentage of the above toughener is 1-15%, preferably 2-10%, more preferably 5-10%.

In a preferred embodiment, the flame retardant is a conventional flame retardant in the art, preferably a melamine derivative, more preferably one of melamine, melamine cyanurate, melamine phosphate, etc. or Several, most preferably, the flame retardant is melamine cyanurate (MCA), and the molecular weight range of the flame retardant is 100-1000.

In a more preferred embodiment, the mass percentage of the above flame retardant is 2-10%, preferably 3-8%.

In a preferred embodiment, the anti-dripping agent is a conventional anti-dripping agent in the art, preferably polytetrafluoroethylene (PTFE) powder, and the molecular weight range of the anti-dripping agent is 3 million-600 Million.

In a more preferred embodiment, the mass percentage of the anti-dripping agent is 0.1-1%, preferably 0.2-0.8%.

Secondly, the present invention also provides a method for preparing the above polyphenylene sulfide composite material. The method includes the following steps:

(1) Weigh polyphenylene sulfide resin, low molecular weight polymer plasticizer, toughening agent, flame retardant, anti-dripping agent according to the mass ratio to obtain a premix;

(2) The obtained premix is added to the extruder, and the mixture extruded from the extruder is cooled and solidified and pelletized to obtain a polyphenylene sulfide composite material.

In a preferred embodiment, the low molecular weight polymer plasticizer has a weight average molecular weight of 1,000-80,000, preferably 10,000-80,000, and more preferably 30,000-70,000. The extruder is a twin-screw extruder. The extruder is preheated in sections before the premix is added to the extruder. After the extrusion is stabilized, the vacuum exhaust pump is turned on.

Finally, the present invention also provides a button on a hard hat brim, a coil skeleton, or a safety protective clothing, which contains any one of the above polyphenylene sulfide composite materials.

In order to make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be further described in detail below in conjunction with specific embodiments.

Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field of the present invention. The terminology used in the description of the present invention herein is for the purpose of describing specific embodiments, and is not intended to limit the present invention.

The following examples and comparative examples use low molecular weight polyethylene with a weight average molecular weight of 40,000 to 50,000, low molecular weight polystyrene with a weight average molecular weight of 60,000 to 70,000, low molecular weight polyethylene glycol ether with a weight average molecular weight of 30,000 to 40,000, and EMA molecular weight It is 6000-10000, MBS molecular weight is 5000-7000, PTFE molecular weight is 4 million-5 million.

Example 1

A polyphenylene sulfide composite material, according to the weight ratio, includes the raw materials in Table 1 below:

Table I

Component weight(%) Polyphenylene sulfide resin 84.5 Low molecular weight polymer plasticizer (low molecular weight polyethylene) 3 Toughener (EMA) 7 Flame retardant (MCA) 5 Anti-dripping agent (PTFE) 0.5

Comparative Example 1

A polyphenylene sulfide composite material, according to the weight ratio, includes the raw materials in Table 2 below:

Table II

Component weight(%) Polyphenylene sulfide resin 87.5 Low molecular weight polymer plasticizer - Toughener (EMA) 7 Flame retardant (MCA) 5 Anti-dripping agent (PTFE) 0.5

Example 2

A polyphenylene sulfide composite material, according to the weight ratio, includes the raw materials in Table 3 below:

Table 3

Component weight(%) Polyphenylene sulfide resin 84.5 Low molecular weight polymer plasticizer (low molecular weight polystyrene) 3 Toughener (MBS) 6 Flame retardant (MCA) 6 Anti-dripping agent (PTFE) 0.5

Example 3

A polyphenylene sulfide composite material, according to the weight ratio, includes the raw materials in Table 4 below:

Table 4

Component weight(%) Polyphenylene sulfide resin 86.5 Low molecular weight polymer plasticizer (low molecular weight polystyrene) 1 Toughener (MBS) 6 Flame retardant (MCA) 6 Anti-dripping agent (PTFE) 0.5

Example 4

A polyphenylene sulfide composite material, according to the weight ratio, includes the raw materials in Table 5 below:

Table 5

Component weight(%) Polyphenylene sulfide resin 79.5 Low molecular weight polymer plasticizer (low molecular weight polystyrene) 8 Toughener (MBS) 6 Flame retardant (MCA) 6 Anti-dripping agent (PTFE) 0.5

Comparative Example 2

A polyphenylene sulfide composite material, according to the weight ratio, includes the raw materials in Table 6 below:

Table 6

Component weight(%) Polyphenylene sulfide resin 87.5 Low molecular weight polymer plasticizer (low molecular weight polystyrene) - Toughener (MBS) 6 Flame retardant (MCA) 6 Anti-dripping agent (PTFE) 0.5

Example 5

A polyphenylene sulfide composite material, according to the weight ratio, includes the raw materials in Table 7 below:

Table 7

Component weight(%) Polyphenylene sulfide resin 84.5 Low molecular weight polymer plasticizer (low molecular weight polyethylene glycol ether) 3 Toughener (EMA) 8 Flame retardant (MCA) 4 Anti-dripping agent (PTFE) 0.5

Comparative Example 3

A polyphenylene sulfide composite material, according to the weight ratio, includes the raw materials in Table 8 below:

Table 8

Component weight(%) Polyphenylene sulfide resin 87.5 Low molecular weight polymer plasticizer (low molecular weight polyethylene) - Toughener (EMA) 8 Flame retardant (MCA) 4 Anti-dripping agent (PTFE) 0.5

The composite materials prepared in the above examples and comparative examples are injection molded into standard test strips according to standard sizes, wherein the standard test strip dimensions of notched impact strength test are: length 80mm, width 10mm, thickness 4mm, remaining width of the bottom of the notch 8mm The radius of the bottom is 0.1mm; the standard sample size of the fire rating test: length 125mm, width 13mm, thickness 1.6mm; melt flow rate test: particle sample. Relevant performance is tested with reference to the following standards:

1. The notched impact strength is tested according to GB / T1043 standard;

2. The fire rating is tested according to ANSI / UL94 standard;

3. The melt flow rate is tested according to the GB / T3682 standard.

The test results of the above embodiments and comparative examples are shown in Table 9:

Table 9

In summary, it can be seen from Table 9 that Example 1 is compared with Comparative Example 1, Example 2-4 is compared with Comparative Example 2, Example 5 is compared with Comparative Example 3, in the presence of a toughener The addition of low molecular weight polymer plasticizers significantly increased the notched impact strength of polyphenylene sulfide composites, which increased the toughness of the materials, indicating that low molecular weight polymer plasticizers and tougheners produced a synergistic effect. In addition, the addition of low molecular weight polymer plasticizers has also greatly increased the melt flow rate of polyphenylene sulfide composite materials, which gives the material good processing flow properties.

In Comparative Examples 2-4, it can be found that the notched impact strength and melt flow rate of the polyphenylene sulfide composite material gradually increase with the increase in the content of the low molecular weight polymer toughener without changing the proportion of other components. After the plasticizer content exceeds 3%, the low molecular weight polymer plasticizer continues to add to the material notch impact strength to a small extent, so when the low molecular weight polymer plasticizer content is 3%, its polyphenylene sulfide compound The material has an ideal toughening effect.

Comparing Examples 1, 2, and 5 it can be known that the polyphenylene sulfide composite material corresponding to low molecular weight polyethylene as a low molecular weight polymer plasticizer at the same content has better notch impact strength and melt flow performance than low Molecular weight polystyrene or low molecular weight polyethylene glycol ether as the polyphenylene sulfide composite material corresponding to the low molecular weight polymer plasticizer.

The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention should be included in the present invention. Within the scope of protection.

Claims (10)

A polyphenylene sulfide composite material, characterized in that it includes the following components in mass percentage:

The polyphenylene sulfide composite material according to claim 1, characterized in that it comprises the following components in mass percentage:

The polyphenylene sulfide composite material according to claim 1 or 2, wherein the polyphenylene sulfide resin is one or two of linear polyphenylene sulfide and cross-linked polyphenylene sulfide Combination, wherein the mass flow rate of linear polyphenylene sulfide melt is 100-400g / 10min; the mass flow rate of cross-linked polyphenylene sulfide melt is 5-200g / 10min. A polyphenylene sulfide composite material according to claim 1 or 2, wherein the low molecular weight polymer plasticizer is selected from one or more of polyester, polyolefin and polyether; preferably, the The low molecular weight polyester is unsaturated polyester, the low molecular weight polyolefin is one or more of low molecular weight polypropylene, low molecular weight polyethylene or low molecular weight polystyrene, and the low molecular weight polyether is polyethylene glycol ether, One or more of polypropylene glycol ether, polyethylene glycol monomethyl ether or polyethylene glycol dimethyl ether. The polyphenylene sulfide composite material according to claim 4, wherein the isotacticity of the low molecular weight polymer plasticizer is 30% -60%, and the low molecular weight polymer plasticizer The weight average molecular weight is 1000-80000, and the molecular weight distribution is 1-10. The polyphenylene sulfide composite material according to claim 1 or 2, wherein the toughening agent is methyl methacrylate-butadiene-styrene ternary random copolymer, ethylene-acrylic acid One or a combination of methyl ester-glycidyl methacrylate ternary random copolymer and maleic anhydride grafted ethylene-octene copolymer. The polyphenylene sulfide composite material according to claim 1 or 2, wherein the flame retardant is a melamine flame retardant, preferably one of melamine, melamine cyanurate, and melamine phosphate One or a combination of several. The polyphenylene sulfide composite material according to claim 1 or 2, wherein the anti-dripping agent is polytetrafluoroethylene. A method for preparing a polyphenylene sulfide composite material according to any one of claims 1-8, characterized in that the method comprises the following steps: (1) Weigh polyphenylene sulfide resin, low molecular weight polymer plasticizer, toughener, flame retardant, anti-dripping agent according to the mass ratio to obtain a premix, and the low molecular weight polymer plasticizer The weight average molecular weight is 1000-80000, the molecular weight distribution is 1-10, and the isotacticity is 30% -60%; (2) The obtained premix is added to the extruder, and the mixture extruded from the extruder is cooled and solidified and pelletized to obtain a polyphenylene sulfide composite material. An article, characterized in that the article comprises the polyphenylene sulfide composite material according to any one of claims 1-8, and the article is selected from a hard hat brim, a coil skeleton or a button on a safety protective clothing.