A polyphenylene sulfide resin composition and preparation method thereof

Abstract

The present invention relates to the technical field of polymer materials, and in particular to a polyphenylene sulfide resin composition and a preparation method thereof. The polyphenylene sulfide resin composition comprises: polyphenylene sulfide, flat glass fiber as a nucleating agent, phosphate ester and polyethylene glycol; the weight ratio of the nucleating agent to the polyphenylene sulfide is greater than or equal to 5:46, the weight ratio of the phosphate ester to the polyphenylene sulfide is greater than or equal to 2:46, and the weight ratio of the polyethylene glycol to the polyphenylene sulfide is greater than or equal to 5:46. The polyphenylene sulfide resin composition of the present invention can eliminate the cold crystallization peak phenomenon of the material system, accelerate the crystallization speed of the material system, and is suitable for filling and reinforcing the polyphenylene sulfide resin composition.

Description

Technical Field

[0001] The invention relates to the technical field of polymer materials, and in particular to a phenylene sulfide resin composition and a preparation method thereof. Background Art

[0002] Polyphenylene sulfide (PPS), also known as polyphenylene sulfide and polyphenylene sulfide, has a melting point of 277-282°C and a glass transition temperature of 85-93°C. Due to the presence of a large number of benzene rings on the main chain of polyphenylene sulfide (PPS), the rigidity of the material is increased, making the unmodified polyphenylene sulfide material relatively brittle, with relatively poor mechanical properties and relatively low heat resistance, so the application of the material is greatly limited. Modifying polyphenylene sulfide with glass fiber or inorganic mineral fillers can improve its mechanical properties and heat resistance, and the heat deformation temperature can reach 260°C.

[0003] Due to the special molecular structure, it has many unique properties, mainly in: excellent thermal stability, chemical stability, dimensional stability, corrosion resistance and electrical properties, excellent physical and mechanical properties, good adhesion, excellent flame retardancy, good electrical properties, and can be blended and modified. At present, it has a wide range of applications in automobile manufacturing, electronics and electrical, chemical industry, instrumentation and aerospace industry, etc.

[0004] The main disadvantages of commonly used polyphenylene sulfide (PPS) are low crystallization temperature and relatively slow crystallization rate, which is specifically manifested in the presence of a cold crystallization peak in the range of 100°C-130°C on the differential scanning calorimetry (DSC) curve of the PPS material. Cold crystallization is the phenomenon that crystallization occurs first and then melts in the process of increasing the temperature from room temperature to the melting point of the polymer. It has been reported (Cui Ning, Li Jie, Wu Pengfei, Wang Ying, Research and Development of Domestic Polyphenylene Sulfide Short Fibers, High-Tech Fibers and Applications, 2008, 33(6): 23-27;) that the cold crystallization peak temperature of Japanese PPS resin chips is 105.9°C, and the cold crystallization peak temperature of domestic PPS resin chips is 121.2°C. In order to achieve the desired crystallinity and ensure product performance, molding is usually carried out at a high mold temperature (130°C-180°C) and for a relatively long molding time. However, due to the limitation of molding equipment, most enterprises find it difficult to ensure that the mold temperature reaches above 130℃. When polyphenylene sulfide materials are molded at a lower mold temperature, the crystallization is not yet complete and the molecular chain segments are frozen, causing the molded products to re-stretch and rearrange and creep when subjected to external forces, causing large deformation of the products, which seriously affects the subsequent use of the products. In order to prevent secondary crystallization, the molded products are usually annealed at a high temperature of 130℃ to 200℃; and for parts made of PPS with large production and demand, the high-temperature annealing process is time-consuming and labor-intensive, and it will also cause problems such as shrinkage of the products after annealing. Furthermore, during the molding process, the mold temperature is low and the cooling time is short. The polyphenylene sulfide material is often not completely crystallized and hardened, and the gate is prone to breakage, which has a certain impact on the production efficiency of the products.

[0005] At present, the idea of ​​accelerating PPS crystallization and reducing the processing mold temperature generally adopts chemical polymerization method (adding a third monomer during PPS polymerization production) and physical method (adding a nucleating agent to the PPS resin matrix) to increase the crystallization temperature (Tm) of the PPS material when cooling from the melt and reduce the glass transition temperature (Tg).

[0006] US patent US5120804: Easily crystallizable polyphenylenesulfidecopolymer and preparation The Japanese Patent No. JP2971930: Method for producing easily crystallized polyfluorinated copolymers (Application No. JP19900250138, Application Date: September 21, 1990; Authorization No. JP2971930 (B2) Authorization Date: November 8, 1999) reports that in order to increase the crystallization rate of PPS, some ethers and other substances are added to the process of synthesizing PPS resin for copolymerization reaction. This method can reduce the Tg of PPS and thus increase the crystallization rate at the processing temperature, and at the same time improve the toughness of the final product. However, this method will reduce the use temperature of the product to a certain extent and will also affect the corrosion resistance of the material.

[0007] In order to solve the problem of lowering the use temperature of PPS due to chemical polymerization, a physical method is used to add inorganic nucleating agents and organic small molecules to PPS to accelerate the crystallization of PPS. Chinese patent CN111574834A reports a polyphenylene sulfide resin composite material, which uses an inorganic nucleating agent zinc carbonate, and is combined with phosphite and silane coupling agents to synergistically accelerate the crystallization rate of the polyphenylene sulfide resin composite material. Chinese patents CN108587165A and CN108485265A report a filled and reinforced polyphenylene sulfide composite material, which uses ultrafine talcum powder and boron nitride as composite inorganic nucleating agents, combined with dibutyl adipate, to accelerate the crystallization rate of the filled and reinforced polyphenylene sulfide composite material.

[0008] In order to further accelerate the crystallization rate of PPS composite materials, a nucleating agent system of an organic nucleating agent and an inorganic nucleating agent can be used. Chinese patent CN111057374A uses an organic nucleating agent, 2,2'-methylene bis (4,6-di-tert-butylphenyl) sodium phosphate, and an inorganic nucleating agent, boron nitride or ultrafine talc, in an organic / inorganic compound nucleating agent system.

[0009] However, the improvement of the crystallization of polyphenylene sulfide materials by inorganic nucleating agents and organic nucleating agents combined with inorganic nucleating agents is relatively limited. In order to improve this problem, fluororesin is added to PPS as a nucleating agent to accelerate the crystallization of PPS. Chinese patent CN107353645B reports an easily crystallized polyphenylene sulfide resin composition, which uses 1-15 parts of polytetrafluoroethylene powder with a melting point of 295°C-315°C as a nucleating agent to accelerate the crystallization of PPS. Furthermore, Chinese patent CN110903650A reports a highly crystalline polyphenylene sulfide composite material that is easy to process and form, using 0.3-2 parts of fluorocarbon resin as a nucleating agent to accelerate the crystallization of PPS. This solution reduces the amount of fluororesin to as low as 0.3 parts by mass.

[0010] However, these methods do not eliminate the cold crystallization peak of the PPS material system, indicating that the crystallization rate of the PPS material system needs to be further improved. At the same time, although the current amount of fluororesin can be as low as 0.3 parts by mass, the hydrofluoric acid produced by the combustion of fluororesin is harmful to the human body. Summary of the invention

[0011] The present invention aims to solve at least one of the above technical problems.

[0012] The inventors have found that using flat glass fiber (flat glass fiber) as a nucleating agent for a polyphenylene sulfide (PPS) resin composition can increase the crystallization temperature Tm of the composite material, eliminate the cold crystallization peak, accelerate its crystallization rate, and meet the requirements of halogen-free flame retardancy.

[0013] A polyphenylene sulfide resin composition comprises: polyphenylene sulfide, a nucleating agent, a phosphate ester and polyethylene glycol; wherein the nucleating agent is a flat glass fiber; the weight ratio of the nucleating agent to polyphenylene sulfide is greater than or equal to 5:46, the weight ratio of the phosphate ester to polyphenylene sulfide is greater than or equal to 2:46, and the weight ratio of the polyethylene glycol to polyphenylene sulfide is greater than or equal to 5:46.

[0014] The inventors have found that the flat glass fiber reduces the shear of the PPS resin, provides better fluidity, reduces the friction and viscosity of the PPS resin, and reduces the entanglement of the PPS resin molecular chains, and promotes the crystallization of the PPS system as a nucleating agent. When the phosphate ester and polyethylene glycol are used as lubricants to accelerate the crystallization of the PPS resin, the movement of the molecular chain is conducive to the folding of the PPS molecular chain and rapid crystallization. The nucleating agent flat glass fiber can work synergistically with the phosphate ester and polyethylene glycol within the above-mentioned ratio range to eliminate the cold crystallization peak of the PPS resin composition, and its combustion products will not produce hydrofluoric acid harmful to the human body.

[0015] According to an embodiment of the present invention, the length of the flat glass fiber is 3-6 mm, and the flatness ratio of the cross section is 3-12.

[0016] Herein, the flat glass fiber is commercially available.

[0017] According to an embodiment of the present invention, the weight ratio of the nucleating agent (ie, flat glass fiber) to polyphenylene sulfide is (5:46)-(20:26).

[0018] According to an embodiment of the present invention, the weight ratio of the phosphate ester to polyphenylene sulfide is (2:46)-(2:26).

[0019] According to an embodiment of the present invention, the phosphate ester is triphenyl phosphate.

[0020] According to an embodiment of the present invention, the weight ratio of polyethylene glycol to polyphenylene sulfide is (5:46)-(5:26).

[0021] According to an embodiment of the present invention, the degree of polymerization of polyethylene glycol is 400-1000, preferably 400, namely PEG400.

[0022] According to an embodiment of the present invention, the polyphenylene sulfide resin composition may further contain other additives, such as one or more of glass fiber, inorganic mineral powder, plasticizer, stabilizer, release agent, filler, dye, pigment and other resins that impart other properties, as long as the effect of the present invention is not impaired.

[0023] According to an embodiment of the present invention, the polyphenylene sulfide resin composition further contains glass fiber; based on the total weight of the polyphenylene sulfide resin composition, the content of the glass fiber is 10-40%.

[0024] According to an embodiment of the present invention, the glass fiber is chopped glass fiber with a length of 3-10 mm and a single fiber diameter of 8-15 um. Adding glass fiber can improve the strength of the polyphenylene sulfide composite material.

[0025] According to an embodiment of the present invention, the polyphenylene sulfide resin composition further contains inorganic mineral powder; based on the total weight of the polyphenylene sulfide resin composition, the content of the inorganic mineral powder is 10-30%.

[0026] According to an embodiment of the present invention, the inorganic mineral powder can be selected from one or a mixture of talc, calcium carbonate, barium sulfate, calcium sulfate, wollastonite, kaolin, and glass microspheres. Adding inorganic mineral powder can improve the strength of the polyphenylene sulfide composite material, reduce anisotropy, and improve the low warpage performance of the material.

[0027] According to an embodiment of the present invention, the polyphenylene sulfide resin composition further contains a processing aid, and the content of the processing aid is 0.3-5% based on the total weight of the polyphenylene sulfide resin composition. Adding the processing aid can improve the epoxy adhesive bonding ability of the polyphenylene sulfide material.

[0028] According to an embodiment of the present invention, the processing aid is epoxy resin.

[0029] According to an embodiment of the present invention, the polyphenylene sulfide resin composition comprises, in parts by weight:

[0030] Polyphenylene sulfide 20-80 parts,

[0031] Nucleating agent 5-20 parts,

[0032] Phosphate 2-10 parts,

[0033] 5-10 parts of polyethylene glycol,

[0034] Glass fiber 10-40 parts,

[0035] Inorganic mineral powder 10-30 parts,

[0036] Processing aids 0.3-5 parts.

[0037] According to an embodiment of the present invention, the polyphenylene sulfide resin composition comprises, in parts by weight:

[0038] 26-46 parts of polyphenylene sulfide,

[0039] Nucleating agent 5-20 parts,

[0040] Phosphate 2-5 parts,

[0041] 5-8 parts of polyethylene glycol,

[0042] Glass fiber 10-30 parts,

[0043] 10-15 parts of inorganic mineral powder,

[0044] Processing aids 0.3-5 parts.

[0045] According to an embodiment of the present invention, the polyphenylene sulfide resin composition is made of the above raw materials, specifically, by melt blending and extrusion granulation.

[0046] According to an embodiment of the present invention, the polyphenylene sulfide resin composition is made of the following raw materials in percentage by weight:

[0047] Polyphenylene sulfide 20-80%,

[0048] Nucleating agent 5-20%,

[0049] Phosphate ester 2-10%,

[0050] Polyethylene glycol 5-10%

[0051] Glass fiber 10-40%,

[0052] Inorganic mineral powder 10-30%,

[0053] Processing aids 0.3-5%.

[0054] According to an embodiment of the present invention, the polyphenylene sulfide resin composition is made of the following raw materials in percentage by weight:

[0055] Polyphenylene sulfide 26-46%,

[0056] Nucleating agent 5-20%,

[0057] Phosphate 2-5%,

[0058] Polyethylene glycol 5-8%,

[0059] Glass fiber 10-30%,

[0060] Inorganic mineral powder 10-15%,

[0061] Processing aids 0.3-5%.

[0062] According to an embodiment of the present invention, the melt flow rate of the polyphenylene sulfide composition is 200-1200 g / 10 min. The test conditions are 316° C. and 5 kg.

[0063] The present invention also provides a method for preparing the polyphenylene sulfide resin composition, which comprises providing raw materials; and preparing the polyphenylene sulfide resin composition by melt blending and extrusion granulation.

[0064] According to an embodiment of the present invention, the method for preparing the polyphenylene sulfide resin composition comprises:

[0065] (1) premixing polyphenylene sulfide resin, phosphate ester, polyethylene glycol and a processing aid to obtain a mixture;

[0066] (2) The mixture obtained in step (1), inorganic mineral powder, glass fiber and nucleating agent are put into an extruder for melt blending and extrusion granulation to obtain a polyphenylene sulfide composition.

[0067] In the above preparation method, in step (2), the polyphenylene sulfide premix is ​​added from the main feeding port, the inorganic mineral powder is fed from the side of zone 4, and the glass fiber and the nucleating agent are fed from the side of zone 7.

[0068] In step (2), the heating temperatures of the extruder are as follows: 270-280°C for zone one, 280-320°C for zone two, 280-320°C for zone three, 280-320°C for zone four, 280-320°C for zone five, 280-320°C for zone six, 280-320°C for zone seven, 280-320°C for zone eight, 280-320°C for zone nine, 280-320°C for zone ten and 290-330°C for the die.

[0069] Due to the selection of the above raw materials, the preparation method of the polyphenylene sulfide resin composition of the present invention is simple, short in time and low in energy consumption.

[0070] The present invention also provides a product, which is made of the polyphenylene sulfide resin composition, or made of the polyphenylene sulfide resin composition and additives and / or other resins. The additives can be selected from additives available in the field of polymer materials.

[0071] Examples of the products described are listed below, but are not limited to these products.

[0072] Electronics: high-voltage components, housings, sockets, terminals on televisions and computers, starting coils, blades, brush brackets and rotor insulation parts of electric motors, contact switches, relays, electric irons, hair dryers, lamp holders, heaters, Class F films, etc.

[0073] Automobile industry: Applicable to exhaust gas recirculation valves and water pump impellers, as well as carburetors, exhaust devices, exhaust regulating valves, light reflectors, bearings, sensor components, etc.

[0074] Mechanical industry: used as bearings, pumps, valves, pistons, precision gears, as well as copiers, cameras, computer parts, catheters, sprayers, fuel injectors, instrument parts, etc.

[0075] Chemical industry: used to make acid and alkali resistant valve pipes, pipe fittings, valves, gaskets and submersible pumps or impellers and other corrosion resistant parts.

[0076] Engineering plastics: used to manufacture automotive parts, anti-corrosion coatings, electrical insulation materials, etc.

[0077] Environmental protection field: PPS fiber filter material is used in smelting, chemical industry, building materials, thermal power, waste incinerator, coal-fired boiler and other industries with high temperature and harsh working conditions. It is a high-quality, high-efficiency and high-temperature resistant filter material.

[0078] Tableware field: used to make chopsticks, spoons, bowls and plates and other tableware.

[0079] Compared with the prior art, the present invention can achieve at least one of the following technical effects:

[0080] 1) Compared with the existing polyphenylene sulfide resin composition and composite material, the cold crystallization peak phenomenon of the material system can be eliminated, the crystallization speed of the material system can be accelerated, and the material system is suitable for filling and reinforcing the polyphenylene sulfide resin composition.

[0081] 2) When the polyphenylene sulfide resin composition of the present invention is burned, no hydrofluoric acid harmful to the human body is generated, and the polyphenylene sulfide resin composition meets the requirements of halogen-free flame retardancy and environmental protection. DETAILED DESCRIPTION

[0082] The present invention will be further described in detail with reference to the following examples, but the present invention should not be limited to these examples.

[0083] The following raw materials were used:

[0084] Polyphenylene sulfide (PPS) was purchased from Zhejiang Xinhecheng Co., Ltd.; glass fiber was purchased from China Fiberglass Jushi Group; flat glass fiber (length 3-6 mm, cross-sectional flatness ratio 3-12) was purchased from Chongqing International Composite Materials Co., Ltd.; triphenyl phosphate was purchased from Zhangjiagang Yarui Chemical Co., Ltd.; polyethylene glycol (PEG400) was purchased from Linyi Guoli Chemical Co., Ltd.; inorganic mineral powder and processing aids (epoxy resin) are all commercially available products.

[0085] The preparation method of the polyphenylene sulfide resin composition is as follows:

[0086] (1) premixing polyphenylene sulfide resin, phosphate ester, polyethylene glycol and a processing aid to obtain a mixture;

[0087] (2) The mixture obtained in step (1), inorganic mineral powder, glass fiber and nucleating agent are put into an extruder for melt blending and extrusion granulation to obtain a polyphenylene sulfide composition.

[0088] In the above preparation method, in step (2), the polyphenylene sulfide premix is ​​added from the main feed port, the inorganic mineral powder is fed from the side of zone 4, and the glass fiber and the nucleating agent are fed from the side of zone 7. In step (2), the heating temperature of the extruder is as follows: 270°C for zone 1, 280°C for zone 2, 280°C for zone 3, 280°C for zone 4, 280°C for zone 5, 290°C for zone 6, 300°C for zone 7, 300°C for zone 8, 300°C for zone 9, 300°C for zone 10 and 310°C for the die.

[0089] Example 1

[0090] A polyphenylene sulfide resin composition comprises the following raw materials (parts by weight): 46 parts of PPS, 30 parts of glass fiber, 10 parts of inorganic mineral powder, 5 parts of flat glass fiber, 2 parts of triphenyl phosphate, 5 parts of PEG400 and 2 parts of a processing aid.

[0091] Example 2

[0092] A polyphenylene sulfide resin composition comprises (by weight): 43 parts of PPS, 30 parts of glass fiber, 10 parts of inorganic mineral powder, 8 parts of flat glass fiber, 2 parts of triphenyl phosphate, 5 parts of PEG400 and 2 parts of processing aid.

[0093] Example 3

[0094] A polyphenylene sulfide resin composition comprises (by weight): 40 parts of PPS, 30 parts of glass fiber, 10 parts of inorganic mineral powder, 11 parts of flat glass fiber, 2 parts of triphenyl phosphate, 5 parts of PEG400 and 2 parts of a processing aid.

[0095] Example 4

[0096] A polyphenylene sulfide resin composition comprises the following raw materials (parts by weight): 32 parts of PPS, 30 parts of glass fiber, 15 parts of inorganic mineral powder, 14 parts of flat glass fiber, 2 parts of triphenyl phosphate, 5 parts of PEG400 and 2 parts of a processing aid.

[0097] Example 5

[0098] A polyphenylene sulfide resin composition comprises the following raw materials (parts by weight): 29 parts of PPS, 30 parts of glass fiber, 15 parts of inorganic mineral powder, 17 parts of flat glass fiber, 2 parts of triphenyl phosphate, 5 parts of PEG400 and 2 parts of a processing aid.

[0099] Example 6

[0100] A polyphenylene sulfide resin composition comprises the following raw materials (parts by weight): 26 parts of PPS, 30 parts of glass fiber, 15 parts of inorganic mineral powder, 20 parts of flat glass fiber, 2 parts of triphenyl phosphate, 5 parts of PEG400 and 2 parts of a processing aid.

[0101] Comparative Example 1

[0102] A polyphenylene sulfide resin composition comprises (by weight): 97.2 parts of PPS, 0.8 parts of zinc carbonate / phosphite, and 2 parts of a processing aid.

[0103] Comparative Example 2

[0104] A polyphenylene sulfide resin composition comprises the following raw materials (by weight): 30.5 parts of PPS, 35 parts of glass fiber, 30 parts of inorganic mineral powder, 4 parts of ultrafine talc powder and a boron nitride / dibutyl adipate nucleating agent, and 0.5 parts of a processing aid.

[0105] Comparative Example 3

[0106] A polyphenylene sulfide resin composition comprises (by weight): 67 parts of PPS, 30 parts of glass fiber, 2.5 parts of ultrafine talc powder and sodium benzoate / ultrafine talc powder nucleating agent, and 0.5 parts of processing aid.

[0107] Comparative Example 4

[0108] A polyphenylene sulfide resin composition comprises (by weight): 90 parts of PPS and 10 parts of polytetrafluoroethylene.

[0109] Comparative Example 5

[0110] A polyphenylene sulfide resin composition comprises (by weight): 39 parts of PPS, 59 parts of glass fiber, 1 part of polyvinylidene fluoride and 1 part of a processing aid.

[0111] Comparative Example 6

[0112] A polyphenylene sulfide resin composition comprises (by weight): 47 parts of PPS, 30 parts of glass fiber, 10 parts of inorganic mineral powder, 4 parts of flat glass fiber, 2 parts of triphenyl phosphate, 5 parts of PEG400 and 2 parts of processing aid.

[0113] Comparative Example 7

[0114] A polyphenylene sulfide resin composition comprises (by weight): 47 parts of PPS, 30 parts of glass fiber, 10 parts of inorganic mineral powder, 5 parts of flat glass fiber, 1 part of triphenyl phosphate, 5 parts of PEG400 and 2 parts of processing aid.

[0115] Comparative Example 8

[0116] A polyphenylene sulfide resin composition comprises (by weight): 47 parts of PPS, 30 parts of glass fiber, 10 parts of inorganic mineral powder, 5 parts of flat glass fiber, 2 parts of triphenyl phosphate, 4 parts of PEG400 and 2 parts of processing aid.

[0117] Comparative Example 9

[0118] A polyphenylene sulfide resin composition comprises (by weight): 46 parts of PPS, 30 parts of glass fiber, 17 parts of inorganic mineral powder, 5 parts of flat glass fiber and 2 parts of processing aid.

[0119] Comparative Example 10

[0120] A polyphenylene sulfide resin composition comprises (by weight): 46 parts of PPS, 30 parts of glass fiber, 20 parts of inorganic mineral powder, 2 parts of triphenyl phosphate and 2 parts of processing aid.

[0121] Comparative Example 11

[0122] A polyphenylene sulfide resin composition comprises (by weight): 46 parts of PPS, 30 parts of glass fiber, 17 parts of inorganic mineral powder, 5 parts of PEG400 and 2 parts of a processing aid.

[0123] Comparative Example 12

[0124] A polyphenylene sulfide resin composition comprises the following raw materials (parts by weight): 46 parts of PPS, 30 parts of glass fiber, 15 parts of inorganic mineral powder, 2 parts of triphenyl phosphate, 5 parts of PEG400 and 2 parts of a processing aid.

[0125] Comparative Example 13

[0126] A polyphenylene sulfide resin composition comprises (by weight): 46 parts of PPS, 30 parts of glass fiber, 12 parts of inorganic mineral powder, 5 parts of flat glass fiber, 5 parts of PEG400 and 2 parts of processing aid.

[0127] Comparative Example 14

[0128] A polyphenylene sulfide resin composition comprises (by weight): 46 parts of PPS, 30 parts of glass fiber, 15 parts of inorganic mineral powder, 5 parts of flat glass fiber, 2 parts of triphenyl phosphate and 2 parts of processing aid.

[0129] Experimental example

[0130] In order to study the crystallization rate of the polyphenylene sulfide resin composition, the crystallization temperature was tested by differential scanning calorimetry (DSC). The sample was first heated to 350°C, kept constant for 3 minutes, and then cooled to 50°C at a rate of 10°C / min. If the crystallization temperature of the material is higher and there is no cold crystallization peak, the crystallization rate is faster and the processing performance is better.

[0131] The polyphenylene sulfide resin composition (plastic particles) prepared by the above method in the embodiment and the comparative example was subjected to DSC test. The test results are shown in Table 1 below.

[0132] Table 1

[0133]

[0134] From comparative examples 1-5, the inorganic nucleating agent system, the organic nucleating agent combined with the inorganic nucleating agent system and the fluororesin nucleating agent system did not eliminate the cold crystallization peak phenomenon of the PPS material system, and the combustion of the fluororesin system produced hydrofluoric acid that was harmful to the human body. From comparative examples 6-14, when the mass fraction of flat glass fiber was greater than or equal to 5 parts, and triphenyl phosphate was ≥ 2 parts, and PEG400 was greater than or equal to 5 parts, the PPS resin composition system would eliminate the cold crystallization peak phenomenon and the crystallization rate would be improved.

[0135] When processed by a twin-screw extruder, because flat glass fibers tend to flow in a planar state like mica, rather than rolling and tumbling like conventional round glass monofilaments, like skateboards, they provide better fluidity by reducing PPS resin shear, reducing PPS resin friction and viscosity, and reducing PPS resin molecular chain entanglement, and as a nucleating agent, promote the crystallization of the PPS system. When triphenyl phosphate and PEG400 are used as lubricants to accelerate the crystallization of PPS resin, the movement of the molecular chain is conducive to the folding of the PPS molecular chain and rapid crystallization. The nucleating agent flat glass fiber works synergistically with triphenyl phosphate and PEG400 to eliminate the cold crystallization peak of the PPS resin composition, and its combustion products will not produce hydrofluoric acid that is harmful to the human body.

[0136] It can be clearly seen from the experimental results of the above examples that the polyphenylene sulfide resin composition of the present invention has no cold crystallization peak phenomenon, the crystallization temperature is increased, and its combustion product does not contain hydrofluoric acid, which meets the halogen-free flame retardant and environmental protection requirements.

[0137] Although the present invention has been described in detail above with general descriptions and specific embodiments, it is obvious to those skilled in the art that some modifications or improvements may be made thereto based on the present invention. Therefore, these modifications or improvements made without departing from the spirit of the present invention all fall within the scope of protection claimed by the present invention.

Claims

1. A polyphenylene sulfide resin composition, characterized in that include: Polyphenylene sulfide, a nucleating agent, a phosphate ester and polyethylene glycol; wherein the nucleating agent is a flat glass fiber; the weight ratio of the nucleating agent to polyphenylene sulfide is greater than or equal to 5:46, the weight ratio of the phosphate ester to polyphenylene sulfide is greater than or equal to 2:46, and the weight ratio of the polyethylene glycol to polyphenylene sulfide is greater than or equal to 5:46; The length of the flat glass fiber is 3-6mm, the flatness ratio of the cross section is 3-12; The weight ratio of the nucleating agent to polyphenylene sulfide is (5:46) - (20:26); The weight ratio of the phosphate ester to polyphenylene sulfide is (2:46)-(2:26); the phosphate ester is triphenyl phosphate; The weight ratio of the polyethylene glycol to the polyphenylene sulfide is (5:46)-(5:26); In parts by weight, the polyphenylene sulfide resin composition comprises: Polyphenylene sulfide 20-80 parts, Nucleating agent 5-20 parts, Phosphate ester 2-10 parts, 5-10 parts of polyethylene glycol, Glass fiber 10-40 parts, Inorganic mineral powder 10-30 parts, Processing aid 0.3-5 parts; The glass fibers are chopped glass fibers.

2. The polyphenylene sulfide resin composition according to claim 1, characterized in that: The polymerization degree of the polyethylene glycol is 400-1000.

3. The polyphenylene sulfide resin composition according to claim 2, characterized in that: The degree of polymerization of the polyethylene glycol is 400.

4. The polyphenylene sulfide resin composition according to any one of claims 1 to 3, characterized in that: In parts by weight, the polyphenylene sulfide resin composition comprises: 26-46 parts of polyphenylene sulfide, Nucleating agent 5-20 parts, Phosphate 2-5 parts, 5-8 parts of polyethylene glycol, Glass fiber 10-30 parts, 10-15 parts of inorganic mineral powder, Processing aids 0.3-5 parts.

5. The polyphenylene sulfide resin composition according to any one of claims 1 to 3, characterized in that: The melt flow rate of the polyphenylene sulfide composition is 200-1200 g / 10 min; the test conditions of the melt flow rate are 316° C. and 5 kg.

6. The polyphenylene sulfide resin composition according to claim 4, characterized in that: The melt flow rate of the polyphenylene sulfide composition is 200-1200 g / 10 min; the test conditions of the melt flow rate are 316° C. and 5 kg.

7. The method for preparing the polyphenylene sulfide resin composition according to any one of claims 1 to 6, characterized in that: include: (1) premixing polyphenylene sulfide resin, phosphate ester, polyethylene glycol and a processing aid to obtain a mixture; (2) The mixture obtained in step (1), inorganic mineral powder, glass fiber and nucleating agent are put into an extruder for melt blending and extrusion granulation to obtain a polyphenylene sulfide composition.

8. A product, characterized in that The invention is made of the polyphenylene sulfide resin composition according to any one of claims 1 to 6, or made of the polyphenylene sulfide resin composition according to any one of claims 1 to 6 and an additive.

9. A product, characterized in that The invention is prepared from the polyphenylene sulfide resin composition according to any one of claims 1 to 6 and other resins.

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