阅读说明：本技术 一种低线性热膨胀系数型再生塑料合成轨枕制备方法 (Preparation method of low-linear thermal expansion coefficient type recycled plastic synthetic sleeper ) 是由 张锐涛 王彦辉 张用兵 张兴刚 魏凯耀 孟雨辰 于 2019-11-29 设计创作，主要内容包括：本发明提供一种低线性热膨胀系数型再生塑料合成轨枕的制备方法,所述方法包括以下步骤：S1,将制备低线性热膨胀系数型再生塑料合成轨枕的原料加入到高速混合机中混合,搅拌均匀；S2,将上述混合好的物料输送至储料仓的型腔内,随后将储料仓传送至高温平板硫化机下模板上,盖上储料仓的上盖板后,将上模板合模；S3,将所述储料仓传送至低温平板硫化机,合模保压降温,到达预定保压时间后将所制得的型材放置在空气中二次冷却至室温；S4,切割所述型材,本发明所述的低线性热膨胀系数型废旧塑料合成轨枕的制备方法过程简单、原材料环保,制备条件简单,易于实施,制备的合成轨枕线性热膨胀系数低,应用范围广。(The invention provides a preparation method of a low-linear thermal expansion coefficient type recycled plastic synthetic sleeper, which comprises the following steps: s1, adding the raw materials for preparing the low linear thermal expansion coefficient type recycled plastic synthetic sleeper into a high-speed mixer for mixing, and uniformly stirring; s2, conveying the mixed materials into a cavity of a storage bin, then conveying the storage bin onto a lower template of a high-temperature flat vulcanizing machine, covering an upper cover plate of the storage bin, and closing an upper template; s3, conveying the storage bin to a low-temperature flat vulcanizing machine, closing the die, maintaining the pressure and cooling, and placing the prepared section in air to cool to room temperature for the second time after the preset pressure maintaining time is reached; s4, cutting the section bar, wherein the preparation method of the low linear thermal expansion coefficient type waste plastic synthetic sleeper has the advantages of simple process, environment-friendly raw materials, simple preparation conditions and easy implementation, and the prepared synthetic sleeper has low linear thermal expansion coefficient and wide application range.)

1. A method for preparing a low linear thermal expansion coefficient type recycled plastic composite sleeper is characterized by comprising the following steps:

s1, preparing the raw materials of the low linear thermal expansion coefficient type recycled plastic synthetic sleeper: adding the base resin, the thermal expansion coefficient modifier, the compatilizer, the flame retardant, the reinforcing filler, the ultraviolet-resistant auxiliary agent, the antioxidant, the coupling agent, the lubricant and the foaming agent into a high-speed mixer, mixing and stirring uniformly;

s2, conveying the mixed materials into a cavity of a storage bin, uniformly laying the mixed materials in the cavity of the storage bin, then conveying the storage bin to a lower template of a high-temperature flat vulcanizing machine, covering an upper cover plate of the storage bin, and closing an upper template; wherein the temperature of the upper template and the lower template of the high-temperature flat vulcanizing machine is set to be 180-260 ℃, the applied pressure is 30-50 MPa, and the forming time is 6-12 h;

s3, after the step S2 is completed, the storage bin is conveyed to a low-temperature flat vulcanizing machine, and the mold is closed, the pressure is maintained, and the temperature is reduced; the temperature of an upper template and a lower template of the low-temperature vulcanizing press is set to be 40-80 ℃, the applied pressure is 30-50 MPa, the pressure maintaining time is 6-12 h, and the prepared section is placed in the air to be cooled to the room temperature for the second time after the preset pressure maintaining time is reached;

and S4, cutting the section according to the size requirement to finally obtain the low linear thermal expansion coefficient type recycled plastic composite sleeper.

2. A method of making a low coefficient of linear thermal expansion type recycled plastic composite tie as claimed in claim 1, wherein said method comprises the steps of:

s1, preparing the raw materials of the low linear thermal expansion coefficient type recycled plastic synthetic sleeper: adding base resin, a thermal expansion coefficient modifier, a compatilizer, a flame retardant, a reinforcing filler, an ultraviolet-resistant auxiliary agent, an antioxidant, a coupling agent, a lubricant and a foaming agent into a high-speed mixer for mixing, wherein the stirring speed of the high-speed mixer is 1000-1500 r/min, and the stirring time is 10 min;

s2, conveying the mixed materials into a cavity of a storage bin, wherein the cavity is cuboid and has the length, width and thickness of 3-6 m, 0.3-2 m and 0.1-0.3 m respectively, uniformly laying the mixed materials in the cavity, conveying the storage bin onto a lower template of a high-temperature flat vulcanizing machine by using a hydraulic device, covering an upper cover plate of the storage bin, and closing the upper template; the temperature of the upper template and the lower template of the high-temperature flat vulcanizing machine is set to be 180-260 ℃, pressure is gradually applied, the final applied pressure is 30-50 MPa, and the forming time is 6-12 hours;

s3, after the step S2 is completed, the storage bin is conveyed to a low-temperature plate vulcanizing machine by using a hydraulic device, and the mold is closed, the pressure is maintained, and the temperature is reduced; the temperature of an upper template and a lower template of the low-temperature vulcanizing press is set to be 40-80 ℃, the applied pressure is 30-50 MPa, the pressure maintaining time is 6-12 h, and the prepared section is placed in the air to be cooled to the room temperature for the second time after the preset pressure maintaining time is reached;

and S4, cutting the section according to the size requirement to obtain the recycled plastic composite sleeper with the low linear thermal expansion coefficient.

3. The method for preparing the recycled plastic composite sleeper with the low linear thermal expansion coefficient as claimed in claim 1, wherein the raw material composition of the recycled plastic composite sleeper with the low linear thermal expansion coefficient comprises the following components in parts by weight: 100 parts of base resin, 35-55 parts of thermal expansion coefficient modifier, 5-10 parts of compatilizer, 30-60 parts of flame retardant, 45-70 parts of reinforcing filler, 0-1 part of ultraviolet light resistant auxiliary agent, 0-2 parts of antioxidant, 1.0-2.5 parts of coupling agent, 0-3 parts of lubricant and 0-4 parts of foaming agent.

4. A low coefficient of linear thermal expansion type recycled plastic composite sleeper as claimed in claim 3, wherein said base resin comprises, in parts by weight: the weight ratio of the high-density polyethylene reclaimed material to the polyethylene oxide to the polystyrene reclaimed material to the reclaimed rubber powder is (55-75): (10-25): 5-20): 5-10.

5. The recycled plastic composite sleeper with low linear thermal expansion coefficient as claimed in claim 3, wherein the thermal expansion coefficient modifier is one or a mixture of more of hollow glass micro-beads, negative thermal expansion coefficient materials, rare earth oxides, glass fibers, carbon fibers, glass fiber reinforced polyethylene and glass fiber reinforced polypropylene.

6. The recycled plastic composite sleeper with low coefficient of linear thermal expansion as claimed in claim 3, wherein said compatilizer is one or more of maleic anhydride grafted polyethylene, maleic anhydride grafted polypropylene, maleic anhydride grafted polyethylene oxide and maleic anhydride grafted polystyrene.

7. The recycled plastic composite sleeper with low linear thermal expansion coefficient as claimed in claim 3, wherein the flame retardant is one or more of magnesium hydroxide, aluminum hydroxide, antimony trioxide, molybdenum trioxide, red phosphorus, zinc borate and melamine.

8. A low coefficient of linear thermal expansion type recycled plastic composite sleeper as claimed in claim 3, wherein said reinforcing filler is one or a mixture of mica, calcium carbonate, montmorillonite and talc.

9. The recycled plastic composite sleeper with low linear thermal expansion coefficient as claimed in claim 3, wherein said anti-ultraviolet light auxiliary agent is one or a mixture of UV531, UV-234, UV-320 and UV-770.

10. The recycled plastic composite sleeper with low coefficient of linear thermal expansion as claimed in claim 3, wherein said antioxidant is one or more of antioxidant 1010, antioxidant 1076, antioxidant 1035 and antioxidant 300.

Technical Field

The invention belongs to the technical field of composite materials for rail transit, and particularly relates to a preparation method of a low-linear thermal expansion coefficient type recycled plastic synthetic sleeper.

Background

At present, three kinds of sleepers are adopted in railway lines, namely a wood sleeper, a concrete sleeper and a glass fiber reinforced polyurethane synthetic sleeper. At present, forest resources are deficient in the global range, and the wooden pillow is easy to age, short in service life and frequent in replacement; the concrete sleeper has the problems of heavy weight, poor elasticity, large mass and low construction efficiency during replacement; the polyurethane synthetic sleeper has high cost and limited application.

Nowadays, the updating and upgrading speed of materials is accelerated, and in many fields, products need to have the characteristics of light weight, high specific strength and low cost. The plastic synthetic sleeper is made of recycled plastic and is prepared by using a large amount of petroleum byproducts. The plastic sleeper also has the advantages of good elasticity, corrosion resistance and aging resistance.

However, thermoplastic materials have a high coefficient of thermal expansion, which is much higher than inorganic materials and metal materials, and thus, the application of thermoplastic materials in some aspects is limited. The thermal expansion coefficient of the plastic sleeper is reduced, and on one hand, the mismatching and assembly clearance with other assembly parts can be reduced; on the other hand, the mechanical stress between the assembly parts caused by thermal expansion can be reduced, so that microcracks generated by the mechanical stress are reduced, and the service life of the product is prolonged.

Therefore, it is one of the technical problems to be solved by those skilled in the art to provide a method for preparing a low linear thermal expansion coefficient type recycled plastic composite sleeper.

Disclosure of Invention

The invention aims to provide a preparation method of a low-linear-thermal-expansion-coefficient type recycled plastic composite sleeper, which aims to solve the problems of high thermal expansion coefficient and limited application of the existing plastic sleeper.

In order to achieve the purpose, the invention adopts the technical scheme that:

a method for preparing a low coefficient of linear thermal expansion type recycled plastic composite sleeper, comprising the steps of:

s1, preparing the raw materials of the low linear thermal expansion coefficient type recycled plastic synthetic sleeper: adding the base resin, the thermal expansion coefficient modifier, the compatilizer, the flame retardant, the reinforcing filler, the ultraviolet-resistant auxiliary agent, the antioxidant, the coupling agent, the lubricant and the foaming agent into a high-speed mixer, mixing and stirring uniformly;

s2, conveying the mixed materials into a cavity of a storage bin, uniformly laying the mixed materials in the cavity of the storage bin, then conveying the storage bin to a lower template of a high-temperature flat vulcanizing machine, covering an upper cover plate of the storage bin, and closing an upper template; wherein the temperature of the upper template and the lower template of the high-temperature flat vulcanizing machine is set to be 180-260 ℃, the applied pressure is 30-50 MPa, and the forming time is 6-12 h;

s3, after the step S2 is completed, the storage bin is conveyed to a low-temperature flat vulcanizing machine, and the mold is closed, the pressure is maintained, and the temperature is reduced; the temperature of an upper template and a lower template of the low-temperature vulcanizing press is set to be 40-80 ℃, the applied pressure is 30-50 MPa, the pressure maintaining time is 6-12 h, and the prepared section is placed in the air to be cooled to the room temperature for the second time after the preset pressure maintaining time is reached;

and S4, cutting the section according to the size requirement to finally obtain the low linear thermal expansion coefficient type recycled plastic composite sleeper.

Further, the method comprises the following steps:

s1, preparing the raw materials of the low linear thermal expansion coefficient type recycled plastic synthetic sleeper: adding base resin, a thermal expansion coefficient modifier, a compatilizer, a flame retardant, a reinforcing filler, an ultraviolet-resistant auxiliary agent, an antioxidant, a coupling agent, a lubricant and a foaming agent into a high-speed mixer for mixing, wherein the stirring speed of the high-speed mixer is 1000-1500 r/min, and the stirring time is 10 min;

s2, conveying the mixed materials into a cavity of a storage bin, wherein the cavity is cuboid and has the length, width and thickness of 3-6 m, 0.3-2 m and 0.1-0.3 m respectively, uniformly laying the mixed materials in the cavity, conveying the storage bin onto a lower template of a high-temperature flat vulcanizing machine by using a hydraulic device, covering an upper cover plate of the storage bin, and closing the upper template; the temperature of the upper template and the lower template of the high-temperature flat vulcanizing machine is set to be 180-260 ℃, pressure is gradually applied, the final applied pressure is 30-50 MPa, and the forming time is 6-12 hours;

s3, after the step S2 is completed, the storage bin is conveyed to a low-temperature plate vulcanizing machine by using a hydraulic device, and the mold is closed, the pressure is maintained, and the temperature is reduced; the temperature of an upper template and a lower template of the low-temperature vulcanizing press is set to be 40-80 ℃, the applied pressure is 30-50 MPa, the pressure maintaining time is 6-12 h, and the prepared section is placed in the air to be cooled to the room temperature for the second time after the preset pressure maintaining time is reached;

and S4, cutting the section according to the size requirement to obtain the recycled plastic composite sleeper with the low linear thermal expansion coefficient.

Further, the low linear thermal expansion coefficient type recycled plastic synthetic sleeper comprises the following raw materials in parts by weight: 100 parts of base resin, 35-55 parts of thermal expansion coefficient modifier, 5-10 parts of compatilizer, 30-60 parts of flame retardant, 45-70 parts of reinforcing filler, 0-1 part of ultraviolet light resistant auxiliary agent, 0-2 parts of antioxidant, 1.0-2.5 parts of coupling agent, 0-3 parts of lubricant and 0-4 parts of foaming agent.

Further, the base resin comprises the following components in parts by weight: the weight ratio of the high-density polyethylene reclaimed material to the polyethylene oxide to the polystyrene reclaimed material to the reclaimed rubber powder is (55-75): (10-25): 5-20): 5-10.

Further, the thermal expansion coefficient modifier is one or a mixture of more of hollow glass microspheres, negative thermal expansion coefficient materials, rare earth oxides, glass fibers, carbon fibers, glass fiber reinforced polyethylene and glass fiber reinforced polypropylene.

Further, the compatilizer is one or a mixture of more of maleic anhydride grafted polyethylene, maleic anhydride grafted polypropylene, maleic anhydride grafted polyethylene oxide and maleic anhydride grafted polystyrene.

Further, the flame retardant is one or a mixture of more of magnesium hydroxide, aluminum hydroxide, antimony trioxide, molybdenum trioxide, red phosphorus, zinc borate and melamine.

Furthermore, the reinforcing filler is one or a mixture of mica, calcium carbonate, montmorillonite and talcum powder.

Furthermore, the ultraviolet light resistant auxiliary agent is one or a mixture of more of UV531, UV-234, UV-320 and UV-770.

Further, the antioxidant is one or a mixture of several of an antioxidant 1010, an antioxidant 1076, an antioxidant 1035 and an antioxidant 300.

The preparation method of the low linear thermal expansion coefficient type recycled plastic synthetic sleeper disclosed by the invention is prepared by using a large amount of recycled plastics, so that the problems of white pollution and energy are solved to a certain extent, and the environment is protected; by utilizing the thermal expansion modifier, the linear thermal expansion coefficient of the plastic synthetic sleeper is reduced, the molding shrinkage capacity of the plastic sleeper is improved, and the application range of the plastic sleeper under the harsh temperature environment condition is enlarged. In addition, the preparation method of the low-linear-thermal-expansion-coefficient type recycled plastic composite sleeper has the advantages of simple process, simple and non-harsh preparation conditions and easy implementation.

Detailed Description

The invention will be further illustrated with reference to specific embodiments. It should be understood that these examples are for illustrative purposes only and are not intended to limit the scope of the present invention. Further, it should be understood that various changes or modifications of the present invention may be made by those skilled in the art after reading the teaching of the present invention, and such equivalents may fall within the scope of the present invention as defined in the appended claims.

The application provides a low linear thermal expansion coefficient type recycled plastic composite sleeper, its constitution includes: 100 parts of base resin, 35-55 parts of thermal expansion coefficient modifier, 5-10 parts of compatilizer, 30-60 parts of flame retardant, 45-70 parts of reinforcing filler, 0-1 part of ultraviolet light resistant auxiliary agent, 0-2 parts of antioxidant, 1.0-2.5 parts of coupling agent, 0-3 parts of lubricant and 0-4 parts of foaming agent.

Further, the base resin comprises the following components: the weight ratio of the high-density polyethylene reclaimed material to the polyethylene oxide to the polystyrene reclaimed material to the reclaimed rubber powder is (55-75): (10-25): 5-20): 5-10.

Further, the thermal expansion coefficient modifier is one or a mixture of more of hollow glass microspheres, negative thermal expansion coefficient materials, rare earth oxides, glass fibers, carbon fibers, glass fiber reinforced polyethylene and glass fiber reinforced polypropylene.

Further, the compatilizer is one or a mixture of more of maleic anhydride grafted polyethylene, maleic anhydride grafted polypropylene, maleic anhydride grafted polyethylene oxide and maleic anhydride grafted polystyrene.

Further, the flame retardant is one or a mixture of more of magnesium hydroxide, aluminum hydroxide, antimony trioxide, molybdenum trioxide, red phosphorus, zinc borate and melamine.

Furthermore, the reinforcing filler is one or a mixture of mica, calcium carbonate, montmorillonite and talcum powder.

Furthermore, the ultraviolet light resistant auxiliary agent is one or a mixture of more of UV531, UV-234, UV-320 and UV-770.

Further, the antioxidant is one or a mixture of several of an antioxidant 1010, an antioxidant 1076, an antioxidant 1035 and an antioxidant 300.

Further, the coupling agent is one or a mixture of more of vinyltrimethoxysilane, vinyltriethoxysilane and aminopropyltriethoxysilane.

Further, the lubricant is one or a mixture of several of paraffin, polyethylene wax, stearate, stearic acid amide and silicone master batch.

Further, the foaming agent is an AC foaming agent.

In addition, the present application also provides a method for preparing a low coefficient of linear thermal expansion type recycled plastic composite sleeper, which is used for preparing the composite sleeper, and comprises the following steps:

s1, adding base resin, a thermal expansion coefficient modifier, a compatilizer, a flame retardant, a reinforcing filler, an ultraviolet light resistant auxiliary agent, an antioxidant, a coupling agent, a lubricant and a foaming agent into a high-speed mixer according to the composition of the low linear thermal expansion coefficient type recycled plastic synthetic sleeper, mixing and uniformly stirring;

s2, conveying the mixed materials into a cavity of a storage bin, uniformly laying the mixed materials in the cavity of the storage bin, then conveying the storage bin to a lower template of a high-temperature flat vulcanizing machine, covering an upper cover plate of the storage bin, and closing an upper template; wherein the temperature of the upper template and the lower template of the high-temperature flat vulcanizing machine is set to be 180-260 ℃, the applied pressure is 30-50 MPa, and the forming time is 6-12 h;

s3, after the step S2 is completed, the storage bin is conveyed to a low-temperature flat vulcanizing machine, and the mold is closed, the pressure is maintained, and the temperature is reduced; the temperature of an upper template and a lower template of the low-temperature vulcanizing press is set to be 40-80 ℃, the applied pressure is 30-50 MPa, the pressure maintaining time is 6-12 h, and the section is placed in the air to be cooled to the room temperature for the second time after the preset pressure maintaining time is reached;

and S4, cutting the section according to the size requirement to finally obtain the low linear thermal expansion coefficient type recycled plastic composite sleeper.

Further, the method comprises the following steps:

s1, adding base resin, a thermal expansion coefficient modifier, a compatilizer, a flame retardant, a reinforcing filler, an ultraviolet light resistant auxiliary agent, an antioxidant, a coupling agent, a lubricant and a foaming agent into a high-speed mixer for mixing according to the composition of the low linear thermal expansion coefficient type recycled plastic synthetic sleeper, wherein the stirring speed of the high-speed mixer is 1000-1500 r/min, and the stirring time is 10 min;

s2, conveying the mixed materials into a cavity of a storage bin, wherein the cavity is cuboid and has the length, width and thickness of 3-6 m, 0.3-2 m and 0.1-0.3 m respectively, uniformly laying the mixed materials in the cavity, conveying the storage bin onto a lower template of a high-temperature flat vulcanizing machine by using a hydraulic device, covering an upper cover plate of the storage bin, and closing the upper template; the temperature of the upper template and the lower template of the high-temperature flat vulcanizing machine is set to be 180-260 ℃, pressure is gradually applied, the final applied pressure is 30-50 MPa, and the forming time is 6-12 hours;

s3, after the step S2 is completed, the storage bin is conveyed to a low-temperature plate vulcanizing machine by using a hydraulic device, and the mold is closed, the pressure is maintained, and the temperature is reduced; the temperature of an upper template and a lower template of the low-temperature vulcanizing press is set to be 40-80 ℃, the applied pressure is 30-50 MPa, the pressure maintaining time is 6-12 h, and the section is placed in the air to be cooled to the room temperature for the second time after the preset pressure maintaining time is reached;

and S4, cutting the section according to the size requirement to obtain the recycled plastic composite sleeper with the low linear thermal expansion coefficient.

The low coefficient of linear thermal expansion type recycled plastic composite sleeper and its preparation described herein are further illustrated by the specific examples below.