Car cover film and preparation method thereof

Abstract

The present invention discloses a car cover film and a preparation method thereof, relating to the technical field of polymer materials. The car cover film comprises the following raw materials, measured by weight: 35-45 parts of acrylate-terminated hyperbranched silicone-modified polyurethane, 3-5 parts of bis(1-vinyl imidazole-2-) ketone, 2-4 parts of diallyl phthalate, 3-5 parts of N-(4-cyano-3-trifluoromethylphenyl) methacrylamide, 2-4 parts of allyl diglycol dicarbonate, 8-12 parts of hyperbranched polysulfoneamine, 1-3 parts of 1,3-bis(oxiranylmethyl)-5-(2-propenyl)-1,3,5-triazine-2,4,6(1H,3H,5H)-trione, 1-3 parts of tricyclo[5.2.1.02,6]decyl acrylate, and 1-3 parts of a photoinitiator. The car cover film has a significant flame retardant effect and excellent wear resistance, aging resistance, and yellowing resistance.

Description

Technical Field

[0001] The present invention relates to the technical field of polymer materials, and in particular to a car cover film and a preparation method thereof. Background Art

[0002] In recent years, with the development of society and the improvement of people's living standards, cars have become a basic household item for most ordinary families. However, due to their long-term exposure to the external environment, the original paint of cars is easily damaged and requires frequent maintenance. It is precisely in this situation that car film has emerged and has attracted widespread attention. Car film is a new high-performance, environmentally friendly film widely used in the automotive beauty and maintenance industry. Applied to the surface of the car body, it isolates the paint from contact with air and rain, preventing aging, corrosion, and discoloration, serving as a protective film for the car paint.

[0003] Existing car cover films are more or less not flame retardant, which can easily cause fire accidents during the production, storage, transportation, vehicle film application and vehicle use of the film. They have insufficient aging resistance and are prone to scratches, scrapes, wear and tear. At the same time, when attached to the corners of the car, they are prone to tearing, which reduces the durability of the car cover film. It also leads to frequent replacement of the car cover film, increases the maintenance cost of the car and other technical defects.

[0004] To address these issues, Chinese invention patent CN114380968B relates to a TPU material specifically designed for car cover films, as well as its preparation and application. Specifically, the invention discloses a thermoplastic polyurethane elastomer that can be used to produce car cover films with excellent transparency, weather resistance, and yellowing resistance. The invention also discloses the preparation and application of the elastomer. However, the material's flame retardancy, wear resistance, high temperature resistance, and aging resistance still require further improvement.

[0005] Therefore, the development of a car cover film with significant flame retardant effect, good wear resistance, aging resistance and yellowing resistance and its preparation method meets market demand, has broad market value and application prospects, and is of great significance to promoting the development of the car cover film field. Summary of the Invention

[0006] The main purpose of the present invention is to provide a car cover film with significant flame retardant effect, good wear resistance, aging resistance and yellowing resistance and a preparation method thereof.

[0007] To achieve the above objectives, the present invention provides a car cover film, which is made of the following raw materials in parts by weight: 35-45 parts of acrylate-terminated hyperbranched silicone-modified polyurethane, 3-5 parts of bis(1-vinylimidazole-2-)ketone, 2-4 parts of diallyl phthalate, 3-5 parts of N-(4-cyano-3-trifluoromethylphenyl)methacrylamide, 2-4 parts of allyl diglycol dicarbonate, 8-12 parts of hyperbranched polysulfoneamine, 1-3 parts of 1,3-bis(oxiranylmethyl)-5-(2-propenyl)-1,3,5-triazine-2,4,6(1H,3H,5H)-trione, 1-3 parts of tricyclo[5.2.1.02,6]dec-8-yl acrylate, and 1-3 parts of a photoinitiator.

[0008] Preferably, there is no special requirement for the source of the acrylate-terminated hyperbranched organosilicon-modified polyurethane. In one embodiment of the present invention, the acrylate-terminated hyperbranched organosilicon-modified polyurethane is prepared according to the method of Example 1 in Chinese invention patent document CN111393608B.

[0009] Preferably, there is no special requirement for the source of the hyperbranched polysulfoneamine. In one embodiment of the present invention, the hyperbranched polysulfoneamine is prepared according to the method of Example 1 in Chinese invention patent document CN108440958B.

[0010] Preferably, the photoinitiator is at least one of benzoin ethyl ether, benzoin isopropyl ether, and 2,4-dihydroxybenzophenone.

[0011] Another object of the present invention is to provide a method for preparing the car cover film, comprising the following steps: mixing the raw materials uniformly by weight to obtain a mixed material, then adding the mixed material to a solvent, stirring evenly, coating the mixed material on the surface of a first release film, and then covering the upper surface with a second release film, and finally curing with ultraviolet light and drying to obtain the car cover film.

[0012] Preferably, the mass ratio of the mixed material to the solvent is 1:(2-3).

[0013] Preferably, the solvent is any one of ethyl acetate, ethylene glycol monomethyl ether, and ethylene glycol methyl ether acetate.

[0014] Preferably, the first release film and the second release film are independently made of transparent PET films.

[0015] Preferably, the thickness of the first release film is 20-50 microns; the thickness of the second release film is 20-50 microns.

[0016] Preferably, the thickness of the car cover film (excluding the first release film and the second release film) is 10-60 microns.

[0017] Preferably, the UV curing and drying are specifically: curing under a 100W UV lamp (365nm) for 6-10 minutes, and then drying at 80-100°C for 1-2 hours.

[0018] Due to the application of the above technical solution, the present invention has the following beneficial effects:

[0019] (1) The method for preparing the car cover film disclosed in the present invention has simple process, convenient operation and control, high preparation efficiency and finished product qualification rate, low dependence on equipment, low energy consumption, small capital investment, is suitable for continuous large-scale production, and has high promotion and application value.

[0020] (2) The car cover film disclosed in the present invention is made of the following raw materials in parts by weight: 35-45 parts of acrylate-terminated hyperbranched silicone-modified polyurethane, 3-5 parts of bis(1-vinyl imidazole-2-) ketone, 2-4 parts of diallyl phthalate, 3-5 parts of N-(4-cyano-3-trifluoromethylphenyl) methacrylamide, 2-4 parts of allyl diglycol dicarbonate, 8-12 parts of hyperbranched polysulfoneamine, 1-3 parts of 1,3-bis(oxiranylmethyl)-5-(2-propenyl)-1,3,5-triazine-2,4,6(1H,3H,5H)-trione, 1-3 parts of tricyclo[5.2.1.02,6]dec-8-yl acrylate, and 1-3 parts of a photoinitiator. Through the mutual cooperation between the raw materials, the prepared car cover film has a significant flame retardant effect, and has good wear resistance, aging resistance, and yellowing resistance.

[0021] (3) The car cover film disclosed in the present invention has components containing unsaturated olefinic bonds that can undergo UV curing under the action of a photoinitiator to form an interconductive network structure. At the same time, the components containing epoxy groups can also undergo epoxy ring-opening reaction with components containing amino groups to form another network structure. The two network structures exist together, which effectively improves the flame retardancy, wear resistance, aging resistance and yellowing resistance of the formed car cover film. At the same time, through the reasonable selection of raw material formula, hyperbranched silicone modified polyurethane, imidazolone, dipropyl phthalate, cyano group, trifluoromethylphenyl, amide, carbonate, hyperbranched polysulfoneamine, triazone and tricyclic [5.2.1.02,6] decan-8-yl ester structures are simultaneously introduced into the film molecular structure. These structures can further improve the above-mentioned properties under the multiple effects of electronic effect, steric effect and conjugation effect. DETAILED DESCRIPTION

[0022] The following description is intended to disclose the present invention so that those skilled in the art can implement the present invention. The preferred embodiments described below are merely examples, and those skilled in the art may conceive of other obvious variations. Example 1

[0023] A car cover film is made from the following raw materials in parts by weight: 35 parts of acrylate-terminated hyperbranched silicone-modified polyurethane, 3 parts of bis(1-vinylimidazole-2-)ketone, 2 parts of diallyl phthalate, 3 parts of N-(4-cyano-3-trifluoromethylphenyl)methacrylamide, 2 parts of allyl diglycol dicarbonate, 8 parts of hyperbranched polysulfoneamine, 1 part of 1,3-bis(oxiranylmethyl)-5-(2-propenyl)-1,3,5-triazine-2,4,6(1H,3H,5H)-trione, 1 part of tricyclo[5.2.1.02,6]dec-8-yl acrylate, and 1 part of a photoinitiator.

[0024] The acrylate-terminated hyperbranched silicone-modified polyurethane is prepared according to the method of Example 1 in Chinese invention patent document CN111393608B; the hyperbranched polysulfoneamine is prepared according to the method of Example 1 in Chinese invention patent document CN108440958B; and the photoinitiator is benzoin ethyl ether.

[0025] A method for preparing the aforementioned car cover film comprises the following steps: uniformly mixing the raw materials by weight to obtain a mixture; then adding the mixture to a solvent, stirring the mixture, and coating the mixture on the surface of a first release film, followed by covering the mixture with a second release film; and finally curing the mixture with UV light and drying the mixture to obtain the car cover film. The mass ratio of the mixture to the solvent is 1:2; the solvent is ethyl acetate. The first and second release films are independently made of transparent PET films. The thickness of the first release film is 20 microns; the thickness of the second release film is 2 microns; and the thickness of the car cover film (excluding the first and second release films) is 30 microns. The UV curing and drying steps are as follows: curing under a 100W UV lamp (365nm) for 6 minutes, followed by drying at 80°C for 1 hour. Example 2

[0026] A car cover film is made from the following raw materials in parts by weight: 37 parts of acrylate-terminated hyperbranched silicone-modified polyurethane, 3.5 parts of bis(1-vinylimidazole-2-)ketone, 2.5 parts of diallyl phthalate, 3.5 parts of N-(4-cyano-3-trifluoromethylphenyl)methacrylamide, 2.5 parts of allyl diglycol dicarbonate, 9 parts of hyperbranched polysulfoneamine, 1.5 parts of 1,3-bis(oxiranylmethyl)-5-(2-propenyl)-1,3,5-triazine-2,4,6(1H,3H,5H)-trione, 1.5 parts of tricyclo[5.2.1.02,6]dec-8-yl acrylate, and 1.5 parts of a photoinitiator.

[0027] The acrylate-terminated hyperbranched silicone-modified polyurethane is prepared according to the method of Example 1 in Chinese invention patent document CN111393608B; the hyperbranched polysulfoneamine is prepared according to the method of Example 1 in Chinese invention patent document CN108440958B; and the photoinitiator is benzoin isopropyl ether.

[0028] A method for preparing the car cover film comprises the following steps: mixing the raw materials in parts by weight to obtain a mixture, adding the mixture to a solvent, stirring the mixture, coating the mixture on the surface of a first release film, covering the second release film on top, and finally curing and drying the mixture with ultraviolet light to obtain the car cover film; the mass ratio of the mixture to the solvent is 1:2.3; the solvent is ethylene glycol monomethyl ether; the first release film and the second release film are independently made of transparent PET film; the thickness of the first release film is 30 microns; the thickness of the second release film is 30 microns; the thickness of the car cover film (excluding the first and second release film parts) is 30 microns; the ultraviolet light curing and drying are specifically: curing under a 100W UV lamp (365nm) for 7 minutes, and then drying at 85°C for 1.2 hours. Example 3

[0029] A car cover film is made from the following raw materials in parts by weight: 40 parts of acrylate-terminated hyperbranched silicone-modified polyurethane, 4 parts of bis(1-vinylimidazole-2-)ketone, 3 parts of diallyl phthalate, 4 parts of N-(4-cyano-3-trifluoromethylphenyl)methacrylamide, 3 parts of allyl diglycol dicarbonate, 10 parts of hyperbranched polysulfoneamine, 2 parts of 1,3-bis(oxiranylmethyl)-5-(2-propenyl)-1,3,5-triazine-2,4,6(1H,3H,5H)-trione, 2 parts of tricyclo[5.2.1.02,6]dec-8-yl acrylate, and 2 parts of a photoinitiator.

[0030] The acrylate-terminated hyperbranched silicone-modified polyurethane was prepared according to the method of Example 1 in Chinese invention patent document CN111393608B; the hyperbranched polysulfoneamine was prepared according to the method of Example 1 in Chinese invention patent document CN108440958B; and the photoinitiator was 2,4-dihydroxybenzophenone.

[0031] A method for preparing the car cover film comprises the following steps: mixing the raw materials in parts by weight to obtain a mixture, adding the mixture to a solvent, stirring the mixture, coating the mixture on the surface of a first release film, covering the second release film on top, and finally curing and drying the mixture with ultraviolet light to obtain the car cover film; the mass ratio of the mixture to the solvent is 1:2.5; the solvent is ethylene glycol methyl ether acetate; the first release film and the second release film are independently made of transparent PET film; the thickness of the first release film is 35 microns; the thickness of the second release film is 35 microns; the thickness of the car cover film (excluding the first and second release film parts) is 30 microns; the ultraviolet light curing and drying are specifically: curing under a 100W UV lamp (365nm) for 8 minutes, and then drying at 90°C for 1.5 hours. Example 4

[0032] A car cover film is made from the following raw materials in parts by weight: 43 parts of acrylate-terminated hyperbranched silicone-modified polyurethane, 4.5 parts of bis(1-vinylimidazole-2-)ketone, 3.5 parts of diallyl phthalate, 4.5 parts of N-(4-cyano-3-trifluoromethylphenyl)methacrylamide, 3.5 parts of allyl diglycol dicarbonate, 11 parts of hyperbranched polysulfoneamine, 2.5 parts of 1,3-bis(oxiranylmethyl)-5-(2-propenyl)-1,3,5-triazine-2,4,6(1H,3H,5H)-trione, 2.5 parts of tricyclo[5.2.1.02,6]dec-8-yl acrylate, and 2.5 parts of a photoinitiator.

[0033] The acrylate-terminated hyperbranched silicone-modified polyurethane is prepared according to the method of Example 1 in Chinese invention patent document CN111393608B; the hyperbranched polysulfoneamine is prepared according to the method of Example 1 in Chinese invention patent document CN108440958B; and the photoinitiator is a mixture of benzoin ethyl ether, benzoin isopropyl ether, and 2,4-dihydroxybenzophenone in a mass ratio of 1:2:3.

[0034] A method for preparing the car cover film comprises the following steps: mixing the raw materials in parts by weight to obtain a mixture, adding the mixture to a solvent, stirring the mixture, coating the mixture on the surface of a first release film, covering the second release film on top, and finally curing and drying the mixture with ultraviolet light to obtain the car cover film; the mass ratio of the mixture to the solvent is 1:2.8; the solvent is ethyl acetate; the first release film and the second release film are independently made of transparent PET film; the thickness of the first release film is 45 microns; the thickness of the second release film is 40 microns; the thickness of the car cover film (excluding the first and second release film parts) is 30 microns; the ultraviolet light curing and drying are specifically: curing under a 100W UV lamp (365nm) for 9 minutes, and then drying at 95°C for 1.8 hours. Example 5

[0035] A car cover film is made from the following raw materials in parts by weight: 45 parts of acrylate-terminated hyperbranched silicone-modified polyurethane, 5 parts of bis(1-vinylimidazole-2-)ketone, 4 parts of diallyl phthalate, 5 parts of N-(4-cyano-3-trifluoromethylphenyl)methacrylamide, 4 parts of allyl diglycol dicarbonate, 12 parts of hyperbranched polysulfoneamine, 3 parts of 1,3-bis(oxiranylmethyl)-5-(2-propenyl)-1,3,5-triazine-2,4,6(1H,3H,5H)-trione, 3 parts of tricyclo[5.2.1.02,6]dec-8-yl acrylate, and 3 parts of a photoinitiator.

[0036] The acrylate-terminated hyperbranched silicone-modified polyurethane is prepared according to the method of Example 1 in Chinese invention patent document CN111393608B; the hyperbranched polysulfoneamine is prepared according to the method of Example 1 in Chinese invention patent document CN108440958B; and the photoinitiator is benzoin ethyl ether.

[0037] A method for preparing the car cover film comprises the following steps: mixing the raw materials in parts by weight to obtain a mixture, adding the mixture to a solvent, stirring the mixture, coating the mixture on the surface of a first release film, covering the second release film thereon, and finally curing and drying the mixture with ultraviolet light to obtain the car cover film; the mass ratio of the mixture to the solvent is 1:3; the solvent is ethylene glycol monomethyl ether; the first release film and the second release film are independently made of transparent PET film; the thickness of the first release film is 50 microns; the thickness of the second release film is 50 microns; the thickness of the car cover film (excluding the first and second release film parts) is 30 microns; the ultraviolet light curing and drying are specifically: curing under a 100W UV lamp (365nm) for 10 minutes, and then drying at 100°C for 2 hours.

[0038] Comparative Example 1

[0039] A car cover film is substantially the same as Example 1, except that bis(1-vinyl imidazole-2-) ketone and tricyclo[5.2.1.02,6]dec-8-yl acrylate are not added.

[0040] Comparative Example 2

[0041] A car cover film is substantially the same as that of Example 1, except that allyl diglycol dicarbonate and hyperbranched polysulfoneamine are not added.

[0042] In order to further illustrate the beneficial technical effects of the car cover films prepared in various embodiments of the present invention, relevant performance tests were conducted on the car cover films prepared in Examples 1-5 and Comparative Examples 1-2. The test results are shown in Table 1. The test method is as follows:

[0043] (1) Wear resistance: Cut each car cover film into test samples, wipe the surface of the test sample with 60% alcohol by mass, and weigh the test sample to three decimal places after the alcohol evaporates, and record it as a; then use a wear tester to test the test sample with a friction pressure of 20N and a friction speed of 43cpm; the friction area is 155mm(L)×50mm(W); the friction time is 30min. After the test is completed, wipe the surface of the test sample with 75% alcohol by mass, and weigh the test sample to three decimal places after the alcohol evaporates, and record it as b; calculate the mass loss rate, which is (ba) / a×100%. The larger the mass loss rate, the worse the wear resistance; the smaller the mass loss rate, the better the wear resistance.

[0044] (2) Flame retardancy: Refer to UL-94 for flame retardancy test.

[0045] (3) Tensile strength: The tensile strength of the sample was tested in accordance with GB / T 13022-1991 Test method for tensile properties of plastic films.

[0046] (4) Heat aging resistance: Each product was placed in an 85°C hot air artificial accelerated aging box for 100 hours of accelerated aging. After cooling to room temperature, the tensile strength test was performed again. The retention rate of tensile strength after aging was calculated. The larger the value, the better the heat aging resistance.

[0047] Table 1

[0048] project wear resistance flame retardancy tensile strength Heat aging resistance unit % class MPa % Example 1 0.161 V-0 33.4 98.2 Example 2 0.149 V-0 35.8 98.6 Example 3 0.135 V-0 38.2 99.5 Example 4 0.115 V-0 39.3 99.7 Example 5 0.105 V-0 41.4 99.5 Comparative Example 1 0.182 V-1 30.5 96.3 Comparative Example 2 0.190 V-2 26.7 93.8

[0049] As can be seen from Table 1, the car cover film disclosed in the embodiment of the present invention has better flame retardancy, wear resistance, mechanical properties and heat aging resistance than the comparative example product; the addition of bis(1-vinylimidazole-2-)ketone, tricyclo[5.2.1.02,6]dec-8-yl acrylate, allyl diglycol dicarbonate and hyperbranched polysulfoneamine is beneficial to improving the above properties.

[0050] The above shows and describes the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and descriptions merely illustrate the principles of the present invention. Various changes and modifications may be made to the present invention without departing from the spirit and scope of the present invention. Such changes and modifications are intended to fall within the scope of the present invention. The scope of protection claimed by the present invention is defined by the appended claims and their equivalents.

Claims

1. A car cover film, characterized in that: The invention comprises the following raw materials in parts by weight: 35-45 parts of acrylate-terminated hyperbranched silicone-modified polyurethane, 3-5 parts of bis(1-vinyl imidazole-2-)ketone, 2-4 parts of diallyl phthalate, 3-5 parts of N-(4-cyano-3-trifluoromethylphenyl) methacrylamide, 2-4 parts of allyl diglycol dicarbonate, 8-12 parts of hyperbranched polysulfoneamine, 1-3 parts of 1,3-bis(oxiranylmethyl)-5-(2-propenyl)-1,3,5-triazine-2,4,6(1H,3H,5H)-trione, 1-3 parts of tricyclo[5.2.1.02,6]dec-8-yl acrylate, and 1-3 parts of a photoinitiator.

2. The car cover film according to claim 1, characterized in that: The photoinitiator is at least one of benzoin ethyl ether, benzoin isopropyl ether and 2,4-dihydroxybenzophenone.

3. A method for preparing the car cover film according to any one of claims 1-2, characterized in that: The method comprises the following steps: mixing the raw materials uniformly by weight to obtain a mixture, adding the mixture into a solvent, stirring the mixture uniformly, coating the mixture on the surface of a first release film, and then covering the surface with a second release film, and finally curing the mixture with ultraviolet light and drying the mixture to obtain a car cover film.

4. The method for preparing a car cover film according to claim 3, characterized in that: The mass ratio of the mixed material to the solvent is 1:(2-3).

5. The method for preparing a car cover film according to claim 3, characterized in that: The solvent is any one of ethyl acetate, ethylene glycol monomethyl ether, and ethylene glycol methyl ether acetate.

6. The method for preparing a car cover film according to claim 3, characterized in that: The first release film and the second release film are independently made of transparent PET films.

7. The method for preparing a car cover film according to claim 3, characterized in that: The thickness of the first release film is 20-50 microns; the thickness of the second release film is 20-50 microns.

8. The method for preparing a car cover film according to claim 3, characterized in that: The thickness of the car cover film is 10-60 microns.

9. The method for preparing a car cover film according to claim 3, characterized in that: The UV curing and drying are specifically as follows: curing under a 100W UV lamp for 6-10 minutes, and then drying at 80-100°C for 1-2 hours.