Preparation method of thermoplastic elastic car cover

Abstract

The invention discloses a thermoplastic elastic vehicle cover preparation method, and relates to the technical field of vehicle protective films, the method comprises the following steps: S1, preparing a thermoplastic material: the thermoplastic material comprises polyol, polyisocyanate, micromolecular polyol, a catalyst, a chain extender, an end-capping reagent, an antioxidant and a light stabilizer; s2, baking and cooling: putting the thermoplastic polyurethane elastomer original adhesive film into a baking oven, baking and then cooling to obtain a thermoplastic polyurethane elastomer film; s3, extrusion forming: performing film extrusion forming: pouring the prepared materials into a film forming machine, and performing extrusion forming; and S4, rolling and transporting. The polyol forms a soft segment, the polyisocyanate and the micromolecule polyol form a hard segment, and the catalyst is responsible for catalyzing an amination reaction between terminal group alcohol and a terminal group isocyanate group in the early stage and a chain extension reaction between the terminal group isocyanate and the chain extender in the chain extension stage. The addition of the antioxidant and the light stabilizer improves the weather resistance of the final polyurethane material.

Description

Technical Field

[0001] The invention relates to the technical field of vehicle protective films, and in particular to a method for preparing a thermoplastic elastic vehicle cover. Background Art

[0002] With the development of the economy and society, the number of cars owned is increasing, and the attention to car maintenance is also increasing. In addition to physical factors such as scratches, bumps, and scratches, chemical factors such as acid rain, oil pollution, haze, and ultraviolet corrosion and oxidation directly damage the car's paint. This will not only affect the owner's driving mood, but also affect the value retention of the vehicle. Compared with the original car paint, the general spray paint has a very limited protective effect, and the price of special spray paint is very high. The emergence of paint protection film provides a relatively feasible solution for car paint protection. Paint protection film, also known as "car cover film" or "invisible car cover", refers to a transparent protective film that is pasted on the outside of the car paint to protect the car paint and enhance the appearance. It has attracted widespread attention in recent years. At present, when producing and preparing thermoplastic elastic car covers, TPU particles need to be used as the main raw material, and hot-melt extruded into a film, and then the back glue and coating are processed, and finally the film needs to be cut into rolls, that is, the preparation of thermoplastic elastic car covers is completed. The following problems exist in the existing technology: 1. The existing preparation method of thermoplastic elastic car cover is usually made of PU material, which has poor resistance to alkaline corrosion and will gradually turn yellow, and scratches cannot be repaired; 2. The existing preparation method of thermoplastic elastic car cover is not convenient for wide promotion and use due to the low toughness of the substrate itself, poor adhesion, great construction difficulty and high production cost. Summary of the invention

[0003] In order to solve the above technical problems, the technical solution adopted by the present invention is: A method for preparing a thermoplastic elastic car cover comprises the following steps: S1. Prepare thermoplastic materials: The thermoplastic materials are composed of polyols, polyisocyanates, small molecule polyols, catalysts, chain extenders, end-capping agents, antioxidants and light stabilizers; S2, baking and cooling: placing the original thermoplastic polyurethane elastomer film in an oven, baking and cooling to obtain a thermoplastic polyurethane elastomer film; S3, extrusion molding: film extrusion molding, pouring the prepared material into the film forming machine, extrusion molding, and then the formed film can be rolled up; S4. Rolling and transportation: Roll up the formed film and use a push cart to transport the rolled film.

[0004] A further improvement of the technical solution of the present invention is that the materials prepared in S1 are 95-100 parts by weight of polyol, 50-65 parts of polyisocyanate, 20-23 parts of small molecule polyol, 0.2 parts of catalyst, 6 parts of chain extender, 15-20 parts of end capping agent, 0.02 parts of antioxidant and 0.02 parts of light stabilizer.

[0005] The further improvement of the technical solution of the present invention is that: the raw materials are mixed and subjected to addition polymerization to obtain a thermoplastic polyurethane material, and the thermoplastic polyurethane film is obtained by coating the thermoplastic polyurethane material and then drying and curing it.

[0006] The further improvement of the technical solution of the present invention lies in that: the polyol includes polyoxypropylene polyol, polymer polyol, polytetramethylene ether glycol and copolyether glycol thereof, polyethylene oxide polyol, polytrimethylene ether glycol and aromatic polyether polyol; the polyisocyanate includes toluene diisocyanate, dimethylmethylene diisocyanate, isophorone diisocyanate, hexamethylene diisocyanate and dicyclohexylmethane diisocyanate; the catalyst includes triethylenediamine, dimethylcyclohexylamine, pentamethyldialkylenetriamine, tetramethylethylenediamine and dimethylethanolamine.

[0007] A further improvement of the technical solution of the present invention is that: during S3 extrusion, a thermoplastic polyurethane elastomer film is pre-set as the first film layer, a PET release film is provided and the PET release film is stretched under a tension of 320N as the second film layer, a transparent flexible TPU film or TPH film is provided as the substrate layer, and a pressure-sensitive adhesive is applied to the substrate layer by a winding coating and bonding line. The coating speed is 6 meters per minute, and a layer of PET release film is composited after the coating is completed.

[0008] A further improvement of the technical solution of the present invention is that a liquid polyurethane coating is provided, a liquid absorbent is added thereto, and the coating is stirred and formed by a machine to form a scratch-resistant and UV-resistant modified polyurethane hardened coating.

[0009] The further improvement of the technical solution of the present invention is that the baking temperature of S2 is 150°C-290°C, the cooling is performed by cooling rollers, the cooling time is 5s-25s, and the cooling temperature is 0°C-45°C.

[0010] Due to the adoption of the above technical solution, the present invention has the following technical advances compared with the prior art: The invention provides a method for preparing a thermoplastic elastic car cover. Under the joint action of polyol, polyisocyanate and catalyst, the polyol constitutes a soft segment, the polyisocyanate and small molecule polyol constitute a hard segment, the catalyst is responsible for catalyzing the amination reaction between the terminal alcohol and the terminal isocyanate group in the early stage and the chain extension reaction between the terminal isocyanate and the chain extender in the chain extension stage, and the addition of an antioxidant and a light stabilizer improves the weather resistance of the final polyurethane material.

[0011] The present invention provides a method for preparing a thermoplastic elastic car cover. Under the action of baking and cooling, a thermoplastic polyurethane elastomer raw film is placed in an oven, baked and then cooled to obtain a thermoplastic polyurethane elastomer film. The obtained thermoplastic polyurethane material is polymerized by long-chain segment raw materials and short-chain segment raw materials, and is a block polymer. Among them, the long-chain diol constitutes the soft segment, and the hard segment is composed of a variety of isocyanates and chain extenders. The thermoplastic polyurethane material prepared from the soft segment and the hard segment has good softness, hardness, strength, elongation and other properties.

[0012] The present invention provides a method for preparing a thermoplastic elastic car cover. Through extrusion molding, a transparent flexible TPU film or TPH film is provided as a substrate layer. Since the substrate used is a TPU thermoplastic polyurethane elastomer or TPH, it has large stretchability and strong flexibility, and is not easy to generate bubbles and wrinkles during the film application process. It has strong aesthetics and is easy to operate. At the same time, the environmentally friendly heat-insulating car cover film also has excellent scratch resistance, aging resistance, yellowing resistance, and thermal repair performance, is very good in UV protection, and has a long service life. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a schematic diagram of the overall process structure of a method for preparing a thermoplastic elastic car cover of the present invention; Figure 2 A schematic diagram of the process structure for preparing thermoplastic materials according to the present invention. Implementation

[0014] The present invention is further described in detail below in conjunction with embodiments: Example

[0015] like Figure 1-2 As shown, the present invention provides a method for preparing a thermoplastic elastic car cover, comprising the following steps: S1. Prepare thermoplastic materials: The thermoplastic materials are composed of polyols, polyisocyanates, small molecule polyols, catalysts, chain extenders, end-capping agents, antioxidants and light stabilizers; S2, baking and cooling: placing the original thermoplastic polyurethane elastomer film in an oven, baking and cooling to obtain a thermoplastic polyurethane elastomer film; S3, extrusion molding: film extrusion molding, pouring the prepared material into the film forming machine, extrusion molding, and then the formed film can be rolled up; S4. Rolling and transportation: Roll up the formed film and use a push cart to transport the rolled film.

[0016] A further improvement of the technical solution of the present invention is that the materials prepared in S1 are 95-100 parts by weight of polyol, 50-65 parts of polyisocyanate, 20-23 parts of small molecule polyol, 0.2 parts of catalyst, 6 parts of chain extender, 15-20 parts of end capping agent, 0.02 parts of antioxidant and 0.02 parts of light stabilizer.

[0017] In this embodiment, polyols constitute the soft segment, polyisocyanates and small molecule polyols constitute the hard segment, the catalyst is responsible for catalyzing the amination reaction between the terminal alcohol and the terminal isocyanate group in the early stage and the chain extension reaction between the terminal isocyanate and the chain extender in the chain extension stage, and the addition of antioxidants and light stabilizers improves the weather resistance of the final polyurethane material. Example

[0018] like Figure 1-2 As shown, on the basis of Example 1, the present invention provides a technical solution: preferably, the raw materials are mixed and subjected to addition polymerization to obtain a thermoplastic polyurethane material, and the thermoplastic polyurethane film is obtained by coating the thermoplastic polyurethane material and drying and curing it, the polyols include polyoxypropylene polyols, polymer polyols, polytetramethylene furan and copolyether glycols thereof, polyethylene oxide polyols, polytrimethylene ether glycols and aromatic polyether polyols; the polyisocyanates include toluene diisocyanate, dimethyl methylene diisocyanate, isophorone diisocyanate, hexamethylene diisocyanate and dicyclohexylmethane diisocyanate; the catalysts include triethylenediamine, dimethylcyclohexylamine, pentamethyldialkylenetriamine, tetramethylethylenediamine and dimethylethylenediamine; Alcoholamine, S3 pre-extrudes a thermoplastic polyurethane elastomer film as the first film layer, provides a PET release film, and stretches the PET release film under a tension of 320N as the second film layer, provides a transparent flexible TPU film or TPH film as a substrate layer, and adopts a winding coating and bonding line to apply pressure-sensitive adhesive on the substrate layer. The coating speed is 6 meters per minute. After the coating is completed, a layer of PET release film is compounded, and a liquid polyurethane coating is provided. A liquid absorbent is added thereto, and the coating is formed by machine stirring to form a scratch-resistant, UV-resistant modified polyurethane hardened coating. The baking temperature of S2 is 150°C-290°C, and the cooling is cooled by a cooling roller. The cooling time is 5s-25s, and the cooling temperature is 0°C-45°C.

[0019] In this embodiment, a thermoplastic polyurethane elastomer film is obtained, and the obtained thermoplastic polyurethane material is polymerized by long-chain segment raw materials and short-chain segment raw materials, and is a block polymer. Among them, the long-chain diol constitutes the soft segment, and the hard segment is composed of a variety of isocyanates and chain extenders. The thermoplastic polyurethane material prepared by the above soft segment and hard segment has good soft and hard, strength, elongation and other properties. The substrate used is TPU thermoplastic polyurethane elastomer or TPH, which has large stretchability and strong flexibility, and is not easy to produce bubbles and wrinkles during the film application process. It has strong aesthetics and is easy to operate. At the same time, the environmentally friendly heat-insulating car cover film also has excellent scratch resistance, anti-aging, anti-yellowing, and thermal repair performance, excellent UV protection, and long service life.

[0020] The working principle of the method for preparing a thermoplastic elastic car cover will be described in detail below.

[0021] like Figure 1-2As shown, the thermoplastic material is composed of polyol, polyisocyanate, small molecule polyol, catalyst, chain extender, end capping agent, antioxidant and light stabilizer. The prepared materials are 95-100 parts by weight of polyol, 50-65 parts of polyisocyanate, 20-23 parts of small molecule polyol, 0.2 parts of catalyst, 6 parts of chain extender, 15-20 parts of end capping agent, 0.02 parts of antioxidant and 0.02 parts of light stabilizer. The raw materials are mixed and subjected to addition polymerization to obtain a thermoplastic polyurethane material. The thermoplastic polyurethane film is obtained by coating the thermoplastic polyurethane material and drying and curing it. The polyol includes polyoxypropylene polyol, polymer Polyols, polytetramethylene glycol and its copolyether glycol, polyethylene oxide polyol, polytrimethylene ether glycol and aromatic polyether polyol; polyisocyanates include toluene diisocyanate, dimethylmethylene diisocyanate, isophorone diisocyanate, hexamethylene diisocyanate and dicyclohexylmethane diisocyanate; catalysts include triethylenediamine, dimethylcyclohexylamine, pentamethyldialkylenetriamine, tetramethylethylenediamine and dimethylethanolamine. Polyols constitute the soft segment, polyisocyanates and small molecule polyols constitute the hard segment, and the catalyst is responsible for catalyzing the amination reaction between the terminal alcohol and the terminal isocyanate group in the early stage and the chain extension stage The chain extension reaction between the terminal isocyanate and the chain extender, the addition of the antioxidant and the light stabilizer improves the weather resistance of the final polyurethane material, the thermoplastic polyurethane elastomer original film is placed in an oven, baked and then cooled to obtain a thermoplastic polyurethane elastomer film, the baking temperature is 150°C-290°C, the cooling is performed by cooling rollers, the cooling time is 5s-25s, the cooling temperature is 0°C-45°C, the film is extruded, the prepared material is poured into a film forming machine, extruded, and then the formed film can be rolled up, the thermoplastic polyurethane elastomer film is pre-set as the first film layer during extrusion, and a PET release film P is provided. The ET release film is stretched under a tension of 320N as the first film layer, and a transparent flexible TPU film or TPH film is provided as the substrate layer. The pressure-sensitive adhesive is applied to the substrate layer by a winding coating and bonding line. The coating speed is 6 meters per minute. After the coating is completed, a layer of PET release film is compounded to provide a liquid polyurethane coating, in which a liquid absorbent is added. The film is stirred and formed by a machine to form a scratch-resistant and UV-resistant modified polyurethane hardened coating. The formed film is rolled up and can be transported by a push cart. The obtained thermoplastic polyurethane material is polymerized by long-chain segment raw materials and short-chain segment raw materials, and is a block polymer.Among them, long-chain diols constitute the soft segment, and the hard segment is composed of a variety of isocyanates and chain extenders. The thermoplastic polyurethane material made from the above soft segment and hard segment has excellent softness, hardness, strength, elongation and other properties. The base material used is TPU thermoplastic polyurethane elastomer or TPH, which has large stretchability and strong flexibility, and is not easy to produce bubbles and wrinkles during the film application process. It has strong aesthetics and is easy to operate. At the same time, the environmentally friendly heat-insulating car cover film also has excellent scratch resistance, anti-aging, anti-yellowing, and thermal repair properties, excellent UV protection, and long service life.

[0022] The above generally describes the present invention in detail, but it is obvious to a person skilled in the art that some modifications or improvements can be made to the present invention. Therefore, modifications or improvements that do not depart from the spirit of the present invention are within the scope of protection of the present invention.

Claims

1. A method for preparing a thermoplastic elastic car cover, comprising the following steps, characterized in that: S1. Prepare thermoplastic materials: The thermoplastic materials are composed of polyols, polyisocyanates, small molecule polyols, catalysts, chain extenders, end-capping agents, antioxidants and light stabilizers; S2, baking and cooling: placing the original thermoplastic polyurethane elastomer film in an oven, baking and cooling to obtain a thermoplastic polyurethane elastomer film; S3, extrusion molding: film extrusion molding, pouring the prepared material into the film forming machine, extrusion molding, and then the formed film can be rolled up; S4. Rolling and transportation: Roll up the formed film and use a push cart to transport the rolled film.

2. The method for preparing a thermoplastic elastic car cover according to claim 1, characterized in that: The materials prepared in S1 are 95-100 parts by weight of polyol, 50-65 parts of polyisocyanate, 20-23 parts of small molecule polyol, 0.2 parts of catalyst, 6 parts of chain extender, 15-20 parts of end capping agent, 0.02 parts of antioxidant and 0.02 parts of light stabilizer.

3. The method for preparing a thermoplastic elastic car cover according to claim 2, characterized in that: The raw materials are mixed and subjected to addition polymerization to obtain a thermoplastic polyurethane material. The thermoplastic polyurethane film is obtained by coating the thermoplastic polyurethane material and then drying and curing it.

4. The method for preparing a thermoplastic elastic car cover according to claim 2, characterized in that: Polyols include polyoxypropylene polyols, polymer polyols, polytetramethylene glycol and copolyether glycols thereof, polyethylene oxide polyols, polytrimethylene ether glycols and aromatic polyether polyols; polyisocyanates include toluene diisocyanate, dimethylmethylene diisocyanate, isophorone diisocyanate, hexamethylene diisocyanate and dicyclohexylmethane diisocyanate; catalysts include triethylenediamine, dimethylcyclohexylamine, pentamethyldialkylenetriamine, tetramethylethylenediamine and dimethylethanolamine.

5. The method for preparing a thermoplastic elastic car cover according to claim 1, characterized in that: During S3 extrusion, a thermoplastic polyurethane elastomer film is pre-placed as the first film layer, a PET release film is provided and stretched under a tension of 320N as the second film layer, a transparent flexible TPU film or TPH film is provided as the substrate layer, and a pressure-sensitive adhesive is applied to the substrate layer by a winding coating and bonding line. The coating speed is 6 meters per minute, and a layer of PET release film is composited after the coating is completed.

6. The method for preparing a thermoplastic elastic car cover according to claim 5, characterized in that: A liquid polyurethane coating is provided, a liquid absorbent is added thereto, and the coating is stirred and formed by a machine to form a scratch-resistant and UV-resistant modified polyurethane hardened coating.

7. The method for preparing a thermoplastic elastic car cover according to claim 1, characterized in that: The baking temperature of S2 is 150°C-290°C, the cooling is performed by cooling with a cooling roller, the cooling time is 5s-25s, and the cooling temperature is 0°C-45°C.

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