Preparation technology of environmentally friendly heat-resistant and flame-retardant polyvinyl chloride material

Abstract

The invention relates to the technical field of polyvinyl chloride, and discloses a preparation process of an environmentally friendly heat-resistant and flame-retardant polyvinyl chloride material, wherein 100 parts by weight of polyvinyl chloride, 5-10 parts by weight of a plasticizer, 3-15 parts by weight of a sulfone-based polyurethane, 0.2-0.3 parts by weight of an antioxidant, 2.5-3.5 parts by weight of a heat stabilizer, 1-5 parts by weight of a flame retardant, etc. are added to a high-speed mixer for mixing, and then extruded and granulated, and injection molded to obtain an environmentally friendly heat-resistant and flame-retardant polyvinyl chloride material. The sulfone-based polyurethane has a hyperbranched three-dimensional molecular chain, which forms a physical chain entanglement with a polyvinyl chloride molecular chain, and the carbamate group contained in the polyurethane forms a hydrogen bond cross-linking network in the polyvinyl chloride material, which has a good toughening effect on the polyvinyl chloride, and improves the toughness and impact strength, high temperature resistance and flame retardancy of the material.

Description

Technical Field

[0001] The invention relates to the technical field of polyvinyl chloride, in particular to a preparation process of an environmentally friendly, heat-resistant and flame-retardant polyvinyl chloride material. Background Art

[0002] Polyvinyl chloride is one of the most widely produced general-purpose plastics in the world. It has good mechanical properties, dielectric properties, and certain flame retardant properties. It is widely used in building pipes, plastic bottles, packaging materials, cable materials, etc. It is usually necessary to add plasticizers to polyvinyl chloride to improve its softness and toughness. However, adding too much plasticizer will affect its heat resistance, strength and flame retardant properties.

[0003] Polyurethane is a polymer material with good elasticity, high toughness and high strength. By using different chain extenders, polyurethane materials with different properties can be obtained. For example, by using carboxylic acid chain extenders, hydrophilic polyurethane can be obtained; by using diphenyl sulfone chain extenders, heat-resistant polyurethane can be obtained; by using diethanolamine, trimethylolpropane, etc. as chain extenders, unique hyperbranched polyurethane can be obtained.

[0004] Using hyperbranched polymers to modify polyvinyl chloride can improve its processing performance, toughness, mechanical strength and other properties. The patent application with publication number CN117511088A discloses polyvinyl chloride composite materials, polyvinyl chloride toughening and reinforcing masterbatch and preparation methods thereof. Fillers such as hyperbranched polyurethane grafted carbon nanotubes and hyperbranched polyurethane grafted graphene nanosheets are added to polyvinyl chloride to improve the mechanical strength, impact resistance and other properties of polyvinyl chloride. However, the patent requires the use of expensive nanomaterials such as carbon nanotubes and graphene, and the preparation methods of hyperbranched polyurethane grafted carbon nanotubes and graphene nanosheets are relatively complicated. Summary of the invention

[0005] The invention provides a preparation process of an environmentally friendly, heat-resistant and flame-retardant polyvinyl chloride material, and solves the problems of poor mechanical properties, high temperature resistance and the like of polyvinyl chloride.

[0006] The technical solution of the present invention is: a preparation process of an environmentally friendly, heat-resistant and flame-retardant polyvinyl chloride material, comprising the following steps:

[0007] Step A, add polyester polyol to a flask, heat to 120°C, and vacuum dehydrate for 2h, add toluene-2,4-diisocyanate at 70-75°C, react for 2-3h in a nitrogen atmosphere, reduce the temperature to 50-55°C, add acetone, the structural formula is The diphenyl sulfone chain extender, dibutyltin dilaurate, was reacted for 1-1.5 hours, and concentrated under reduced pressure to obtain sulfone-based polyurethane;

[0008] Step B, adding 100 parts by weight of polyvinyl chloride, 5-10 parts by weight of plasticizer, 3-15 parts by weight of sulfone-based polyurethane, 0.2-0.3 parts by weight of antioxidant, 2.5-3.5 parts by weight of heat stabilizer, 1-5 parts by weight of flame retardant, 0.5-1 parts by weight of lubricating aid, and 2-10 parts by weight of filler into a high-speed mixer, mixing at 100-120° C., then extruding and granulating the materials in a twin-screw extruder, with the temperature of the sixth stage being 150-175° C., and finally performing injection molding in an injection molding machine, with the temperature of the third stage being 160-175° C., to obtain an environmentally friendly, heat-resistant, flame-retardant polyvinyl chloride material.

[0009] Furthermore, the molar ratio of polyester polyol, toluene-2,4-diisocyanate, diphenyl sulfone chain extender, and dibutyltin dilaurate is 1: (2.2-2.4): (0.5-0.55): (0.006-0.007).

[0010] Furthermore, the polyester polyol is polycaprolactone diol 2000 or polybutylene adipate diol 2000.

[0011] Furthermore, the preparation process of the diphenyl sulfone chain extender is as follows: add methanol, ethanol or 1,4-dioxane reaction solvent, phenyl glycidyl ether and 4,4'-diaminodiphenyl sulfone in a molar ratio of (2-2.4):1 to a flask, stir and react at 50-80°C for 3-6 hours, concentrate under reduced pressure after the reaction, separate by silica gel column chromatography, and gradient elute with dichloromethane and methanol solution to obtain the diphenyl sulfone chain extender. The reaction formula is: .

[0012] Furthermore, the heat stabilizer is tribasic lead sulfate, dibasic lead sulfate or dibasic lead phosphite; and the antioxidant is antioxidant 1010 or antioxidant 168.

[0013] Furthermore, the plasticizer is diisononyl phthalate or dioctyl phthalate; and the lubricating auxiliary agent is stearic acid, calcium stearate or zinc stearate.

[0014] Furthermore, the flame retardant is antimony trioxide or zinc stannate; and the filler is calcium carbonate or white carbon black.

[0015] The invention has the following beneficial effects: phenyl glycidyl ether and 4,4'-diaminodiphenyl sulfone are reacted to generate a diphenyl sulfone chain extender containing multiple hydroxyl and imino polymerization sites, and then a polymerization reaction is carried out with polyester polyol and toluene-2,4-diisocyanate to obtain a hyperbranched sulfone-based polyurethane. Then, polyvinyl chloride is modified, and the sulfone-based polyurethane has a hyperbranched three-dimensional molecular chain, which forms a physical chain entanglement with the polyvinyl chloride molecular chain, and the carbamate group contained in the polyurethane forms a hydrogen bond cross-linking network in the polyvinyl chloride material, which has a good toughening effect on the polyvinyl chloride. When the material is subjected to stress and impact, the hyperbranched polyurethane can dissipate part of the impact energy through stress transfer, and it forms silver streaks and shear bands in the polyvinyl chloride body as a stress concentrator, which can dissipate stress, thereby improving the toughness and impact strength of the material, and showing higher elongation at break and impact strength.

[0016] The sulfone-based polyurethane of the present invention contains a high-temperature-resistant diphenyl sulfone structure, and its hyperbranched three-dimensional molecular chain forms a physical chain entanglement with the polyvinyl chloride molecular chain, so that the polyvinyl chloride maintains good structural stability and is not prone to thermal decomposition, which is beneficial to improving the thermal decomposition temperature and high-temperature resistance. In addition, diphenyl sulfone, as a flame retardant group, can improve the limiting oxygen index and flame retardant performance of the polyvinyl chloride. DETAILED DESCRIPTION

[0017] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0018] Embodiment 1: The preparation process of environmentally friendly heat-resistant flame-retardant polyvinyl chloride material comprises the following steps:

[0019] (1) Add 50 mL of methanol, 36 mmol of phenyl glycidyl ether, and 15 mmol of 4,4'-diaminodiphenyl sulfone into a flask, heat to 50°C, stir and react for 4 hours, concentrate under reduced pressure, separate by silica gel column chromatography, and elute with a gradient of dichloromethane and methanol solution to obtain a diphenyl sulfone chain extender;

[0020] (2) Add 20 mmol of polybutylene adipate diol 2000 to a flask, heat to 120°C, and vacuum dehydrate for 2 hours. Add 48 mmol of toluene-2,4-diisocyanate at 70°C, react for 2 hours in a nitrogen atmosphere, lower the temperature to 50°C, add acetone, 10 mmol of diphenyl sulfone chain extender, and 0.13 mmol of dibutyltin dilaurate, react for 1 hour, and concentrate under reduced pressure to obtain sulfone polyurethane;

[0021] (3) Add 100g polyvinyl chloride, 5g plasticizer dioctyl phthalate, 3g sulfone polyurethane, 0.2g antioxidant 1010, 3.5g heat stabilizer dibasic lead sulfate, 2g flame retardant antimony trioxide, 0.8g lubricating aid stearic acid, and 10g filler calcium carbonate into a high-speed mixer and mix at 120°C. Then, extrude the material into granules in a twin-screw extruder with six-stage temperatures of 150°C, 160°C, 160°C, 170°C, 175°C, and 175°C. Finally, injection molding is performed in an injection molding machine with three-stage temperatures of 160°C, 170°C, and 175°C to obtain an environmentally friendly, heat-resistant, flame-retardant polyvinyl chloride material.

[0022] Embodiment 2: A process for preparing an environmentally friendly, heat-resistant and flame-retardant polyvinyl chloride material, comprising the following steps:

[0023] (1) Add 60 mL of 1,4-dioxane, 30 mmol of phenyl glycidyl ether, and 15 mmol of 4,4'-diaminodiphenyl sulfone into a flask, heat to 80°C, stir and react for 3 hours, concentrate under reduced pressure, separate by silica gel column chromatography, and use a gradient elution of dichloromethane and methanol solution to obtain a diphenyl sulfone chain extender;

[0024] (2) Add 20 mmol of polybutylene adipate diol 2000 to a flask, heat to 120°C, and vacuum dehydrate for 2 hours. Add 48 mmol of toluene-2,4-diisocyanate at 70°C, react for 2 hours in a nitrogen atmosphere, lower the temperature to 50°C, add acetone, 11 mmol of diphenyl sulfone chain extender, and 0.12 mmol of dibutyltin dilaurate, react for 1 hour, and concentrate under reduced pressure to obtain sulfone polyurethane;

[0025] (3) Add 100g polyvinyl chloride, 5g plasticizer diisononyl phthalate, 7g sulfone polyurethane, 0.26g antioxidant 168, 2.5g heat stabilizer tribasic lead sulfate, 5g flame retardant zinc stannate, 0.5g lubricating aid zinc stearate, and 8g filler calcium carbonate into a high-speed mixer and mix at 100°C. Then, extrude the material into granules in a twin-screw extruder with six temperature sections of 150°C, 160°C, 160°C, 170°C, 175°C, and 175°C. Finally, perform injection molding in an injection molding machine with three temperature sections of 160°C, 170°C, and 175°C to obtain an environmentally friendly, heat-resistant, flame-retardant polyvinyl chloride material.

[0026] Embodiment 3: A process for preparing an environmentally friendly, heat-resistant and flame-retardant polyvinyl chloride material, comprising the following steps:

[0027] (1) Add 60 mL of ethanol, 33 mmol of phenyl glycidyl ether, and 15 mmol of 4,4'-diaminodiphenyl sulfone into a flask, heat to 60°C, stir and react for 5 hours, concentrate under reduced pressure, separate by silica gel column chromatography, and use a gradient elution of dichloromethane and methanol solution to obtain a diphenyl sulfone chain extender;

[0028] (2) Add 20 mmol of polycaprolactone diol 2000 to a flask, heat to 120°C, and vacuum dehydrate for 2 hours. Add 46 mmol of toluene-2,4-diisocyanate at 70°C, react for 3 hours in a nitrogen atmosphere, reduce the temperature to 50°C, add acetone, 10 mmol of diphenyl sulfone chain extender, and 0.14 mmol of dibutyltin dilaurate, react for 1.5 hours, and concentrate under reduced pressure to obtain sulfone polyurethane;

[0029] (3) Add 100g polyvinyl chloride, 5g plasticizer dioctyl phthalate, 11g sulfone polyurethane, 0.3g antioxidant 168, 3.2g heat stabilizer tribasic lead sulfate, 1g flame retardant antimony trioxide, 1g lubricating aid calcium stearate, and 2g filler white carbon black into a high-speed mixer and mix at 120°C. Then, extrude and granulate the materials in a twin-screw extruder with six temperatures of 150°C, 160°C, 160°C, 170°C, 175°C, and 175°C. Finally, injection molding is performed in an injection molding machine with three temperatures of 160°C, 170°C, and 175°C to obtain an environmentally friendly, heat-resistant, flame-retardant polyvinyl chloride material.

[0030] Embodiment 4: A process for preparing an environmentally friendly, heat-resistant and flame-retardant polyvinyl chloride material, comprising the following steps:

[0031] (1) Prepare a diphenyl sulfone chain extender according to the method of Example 1;

[0032] (2) Add 20 mmol of polycaprolactone diol 2000 to a flask, heat to 120°C, and vacuum dehydrate for 2 hours. Add 44 mmol of toluene-2,4-diisocyanate at 75°C, react for 3 hours in a nitrogen atmosphere, reduce the temperature to 50°C, add acetone, 10 mmol of diphenyl sulfone chain extender, and 0.12 mmol of dibutyltin dilaurate, react for 1.5 hours, and concentrate under reduced pressure to obtain sulfone polyurethane;

[0033] (3) Add 100g of polyvinyl chloride, 10g of plasticizer dioctyl phthalate, 15g of sulfone polyurethane, 0.3g of antioxidant 1010, 3.5g of heat stabilizer dibasic lead phosphite, 5g of flame retardant zinc stannate, 0.8g of lubricating aid stearic acid, and 10g of filler calcium carbonate into a high-speed mixer and mix well at 110°C. Then, extrude and granulate the materials in a twin-screw extruder with six-stage temperatures of 150°C, 160°C, 160°C, 170°C, 175°C, and 175°C. Finally, injection molding is performed in an injection molding machine with three-stage temperatures of 160°C, 170°C, and 175°C to obtain an environmentally friendly, heat-resistant, flame-retardant polyvinyl chloride material.

[0034] Comparative Example 1: The preparation process of environmentally friendly heat-resistant and flame-retardant polyvinyl chloride material is as follows:

[0035] (1) Add 100g of polyvinyl chloride, 5g of plasticizer dioctyl phthalate, 0.2g of antioxidant 1010, 3.5g of heat stabilizer dibasic lead sulfate, 2g of flame retardant antimony trioxide, 0.8g of lubricating aid stearic acid, and 10g of filler calcium carbonate into a high-speed mixer and mix them at 120°C. Then, extrude and granulate the materials in a twin-screw extruder with six-stage temperatures of 150°C, 160°C, 160°C, 170°C, 175°C, and 175°C. Finally, injection molding is performed in an injection molding machine with three-stage temperatures of 160°C, 170°C, and 175°C to obtain an environmentally friendly, heat-resistant, flame-retardant polyvinyl chloride material.

[0036] Comparative Example 2: The preparation process of environmentally friendly heat-resistant and flame-retardant polyvinyl chloride material is as follows:

[0037] (1) Add 20 mmol of polybutylene adipate diol 2000 to a flask, heat to 120°C, and vacuum dehydrate for 2 hours. Add 48 mmol of toluene-2,4-diisocyanate at 70°C, react for 2 hours in a nitrogen atmosphere, lower the temperature to 50°C, add acetone, 20 mmol of 4,4'-diaminodiphenyl sulfone, and 0.13 mmol of dibutyltin dilaurate, react for 1 hour, and concentrate under reduced pressure to obtain sulfone polyurethane.

[0038] (2) Add 100g of polyvinyl chloride, 5g of plasticizer dioctyl phthalate, 3g of sulfone polyurethane, 0.2g of antioxidant 1010, 3.5g of heat stabilizer dibasic lead sulfate, 2g of flame retardant antimony trioxide, 0.8g of lubricating aid stearic acid, and 10g of filler calcium carbonate into a high-speed mixer and mix them at 120°C. Then, extrude and granulate the materials in a twin-screw extruder with six temperatures of 150°C, 160°C, 160°C, 170°C, 175°C, and 175°C. Finally, injection molding is performed in an injection molding machine with three temperatures of 160°C, 170°C, and 175°C to obtain an environmentally friendly, heat-resistant, flame-retardant polyvinyl chloride material.

[0039] Comparative Example 3: The preparation process of environmentally friendly heat-resistant and flame-retardant polyvinyl chloride material is as follows:

[0040] (1) Add 20 mmol of polybutylene adipate diol 2000 to a flask, heat to 120°C, and vacuum dehydrate for 2 hours. Add 48 mmol of toluene-2,4-diisocyanate at 70°C, react for 2 hours in a nitrogen atmosphere, lower the temperature to 50°C, add acetone, 13.33 mmol of diethanolamine, and 0.13 mmol of dibutyltin dilaurate, react for 1 hour, and concentrate under reduced pressure to obtain polyurethane.

[0041] (2) Add 100g of polyvinyl chloride, 30g of plasticizer dioctyl phthalate, 3g of polyurethane, 0.2g of antioxidant 1010, 3.5g of heat stabilizer dibasic lead sulfate, 2g of flame retardant antimony trioxide, 0.8g of lubricating aid stearic acid, and 10g of filler calcium carbonate into a high-speed mixer and mix at 120°C. Then, extrude and granulate the materials in a twin-screw extruder with six-stage temperatures of 150°C, 160°C, 160°C, 170°C, 175°C, and 175°C. Finally, injection molding is performed in an injection molding machine with three-stage temperatures of 160°C, 170°C, and 175°C to obtain an environmentally friendly, heat-resistant, flame-retardant polyvinyl chloride material.

[0042] The tensile properties of PVC materials are tested according to GB / T 1040.1-2018. The impact strength is tested according to GB / T1043.1-2008.

[0043] The flame retardant properties are tested according to GB / T 2406.1-2008. The thermal properties are tested using a thermogravimetric analyzer in a nitrogen atmosphere at a temperature of 20-700°C.

[0044] Table 1: Mechanical properties test results of polyvinyl chloride materials of various embodiments and comparative examples

[0045]

[0046] As can be seen from Table 1, sulfone-based polyurethane is added in Examples 1 to 4, and the polyurethane has good toughness and strength. At the same time, the diphenyl sulfone chain extender contains multiple hydroxyl and imino polymerization sites. The sulfone-based polyurethane obtained by the reaction has a hyperbranched three-dimensional molecular chain, which forms a physical chain entanglement with the polyvinyl chloride molecular chain, and the carbamate group contained in the polyurethane forms a hydrogen bond cross-linking network in the polyvinyl chloride material, which has a good toughening effect on the polyvinyl chloride. When the material is subjected to stress and impact, the hyperbranched polyurethane can dissipate part of the impact energy through stress transfer. It forms silver streaks and shear bands in the polyvinyl chloride body as a stress concentrator, which can dissipate stress, thereby improving the toughness and impact strength of the material, and showing higher elongation at break and impact strength.

[0047] The difference between Comparative Example 1 and Example 1 is that without adding sulfone-based polyurethane, the toughness of polyvinyl chloride is poor, and the elongation at break and impact strength are significantly lower than those in Example 1.

[0048] The main difference between Comparative Example 2 and Example 1 is that 4,4'-diaminodiphenyl sulfone is used instead of diphenyl sulfone chain extender to prepare sulfone-based polyurethane. 4,4'-diaminodiphenyl sulfone contains only two amino polymerization sites. The sulfone-based polyurethane obtained by polymerization has a linear structure and does not have a hyperbranched three-dimensional molecular chain. The toughening effect is not good, and the tensile properties and impact strength are lower than those in Example 1.

[0049] The main difference between Comparative Example 3 and Example 1 is that diethanolamine is used instead of diphenyl sulfone chain extender to prepare sulfone polyurethane, and diethanolamine also has multiple hydroxyl and imino polymerization sites. The sulfone polyurethane obtained by polymerization has a hyperbranched three-dimensional molecular chain, has a better toughening effect on polyvinyl chloride, and has higher elongation at break and impact strength.

[0050] Table 2: Test results of thermal properties and flame retardant properties of polyvinyl chloride in various embodiments and comparative examples

[0051]

[0052] As shown in Table 2, sulfone-based polyurethane is added in Examples 1 to 4, which contains a diphenyl sulfone structure with high temperature resistance, and the sulfone-based polyurethane has a hyperbranched three-dimensional molecular chain, which forms a physical chain entanglement with the polyvinyl chloride molecular chain, so that the polyvinyl chloride maintains good structural stability, is not easy to thermally decompose, and is conducive to increasing the thermal decomposition temperature. At the same time, diphenyl sulfone, as a flame retardant group, can improve the limiting oxygen index and flame retardant performance of polyvinyl chloride. Compared with Example 1, the thermal decomposition temperature and limiting oxygen index of the polyvinyl chloride materials of Comparative Examples 1 to 3 are lower.

[0053] The above contents are merely examples and explanations of the present invention. Those skilled in the art may make various modifications or additions to the specific embodiments described or replace them in a similar manner. As long as they do not deviate from the invention or exceed the scope defined by the claims, they shall all fall within the protection scope of the present invention.

Claims

1. A process for preparing an environmentally friendly, heat-resistant and flame-retardant polyvinyl chloride material, characterized in that: The following steps are involved: Step A, add polyester polyol to a flask, heat and vacuum dehydrate, add toluene-2,4-diisocyanate at 70-75°C, react for 2-3h in a nitrogen atmosphere, reduce the temperature to 50-55°C, add acetone, the structural formula is The diphenyl sulfone chain extender, dibutyltin dilaurate, was reacted for 1-1.5 hours, and concentrated under reduced pressure to obtain sulfone-based polyurethane; Step B, adding 100 parts by weight of polyvinyl chloride, 5-10 parts by weight of plasticizer, 3-15 parts by weight of sulfone-based polyurethane, 0.2-0.3 parts by weight of antioxidant, 2.5-3.5 parts by weight of heat stabilizer, 1-5 parts by weight of flame retardant, 0.5-1 parts by weight of lubricating aid, and 2-10 parts by weight of filler into a high-speed mixer, mixing at 100-120° C., then extruding and granulating the materials in a twin-screw extruder, with the temperature of the sixth stage being 150-175° C., and finally performing injection molding in an injection molding machine, with the temperature of the third stage being 160-175° C., to obtain an environmentally friendly, heat-resistant, flame-retardant polyvinyl chloride material; The molar ratio of the polyester polyol, toluene-2,4-diisocyanate, diphenyl sulfone chain extender and dibutyltin dilaurate is 1:(2.2-2.4):(0.5-0.55):(0.006-0.007).

2. The preparation process of the environmentally friendly, heat-resistant and flame-retardant polyvinyl chloride material according to claim 1, characterized in that: The polyester polyol is polycaprolactone diol 2000 or polybutylene adipate diol 2000.

3. The preparation process of the environmentally friendly, heat-resistant and flame-retardant polyvinyl chloride material according to claim 1, characterized in that: The preparation process of the diphenyl sulfone chain extender comprises: adding a reaction solvent, phenyl glycidyl ether and 4,4'-diaminodiphenyl sulfone into a flask, concentrating under reduced pressure after the reaction, separating by silica gel column chromatography, and eluting with a dichloromethane and methanol solution in a gradient manner to obtain the diphenyl sulfone chain extender.

4. The preparation process of the environmentally friendly, heat-resistant and flame-retardant polyvinyl chloride material according to claim 3, characterized in that: The reaction solvent is methanol, ethanol or 1,4-dioxane.

5. The preparation process of the environmentally friendly, heat-resistant and flame-retardant polyvinyl chloride material according to claim 3, characterized in that: The molar ratio of the phenyl glycidyl ether to 4,4'-diaminodiphenyl sulfone is (2-2.4):

1.

6. The preparation process of the environmentally friendly, heat-resistant and flame-retardant polyvinyl chloride material according to claim 3, characterized in that: The reaction was stirred at 50-80°C for 3-6 h.

7. The preparation process of the environmentally friendly, heat-resistant and flame-retardant polyvinyl chloride material according to claim 1, characterized in that: The heat stabilizer is tribasic lead sulfate, dibasic lead sulfate or dibasic lead phosphite; the antioxidant is antioxidant 1010 or antioxidant 168.

8. The process for preparing the environmentally friendly, heat-resistant and flame-retardant polyvinyl chloride material according to claim 1, characterized in that: The plasticizer is diisononyl phthalate or dioctyl phthalate; the lubricating auxiliary agent is stearic acid, calcium stearate or zinc stearate.

9. The process for preparing the environmentally friendly, heat-resistant and flame-retardant polyvinyl chloride material according to claim 1, characterized in that: The flame retardant is antimony trioxide or zinc stannate; the filler is calcium carbonate or white carbon black.

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