CN-122011475-A - Scratch-resistant release film and preparation method thereof

Abstract

The application discloses a scratch-resistant release film which comprises, by mass, 80-95 parts of PET resin, 5-15 parts of thermoplastic polyurethane, 1-5 parts of a toughening agent, 0.1-0.5 part of a tetrapentaerythritol ester antioxidant and 1-3 parts of a POE-g-MAH compatilizer, and a release coating, wherein the release coating comprises, by mass, 30-50 parts of an organosilicon release agent, 10-20 parts of an abrasion-resistant auxiliary agent, 2-5 parts of a crosslinking agent, 0.1-0.5 part of a catalyst, 2-5 parts of ethoxypolysilazane and 80-120 parts of a solvent, the abrasion-resistant auxiliary agent comprises polytetrafluoroethylene micro powder and an organic surface modified boron nitride, and the solvent is a mixed solvent of ethyl acetate and isopropanol, and the release film prepared from the components has flexibility and scratch-resistant performance.

Inventors

• YIN LI
• GUO PING

Assignees

• 苏州腾盛薄膜科技有限公司

Dates

Publication Date

20260512

Application Date

20260224

Claims (8)

1. 1. A scratch-resistant release film is characterized by comprising a substrate layer and a release coating, The substrate layer comprises the following components in parts by mass: 80-95 parts of PET resin, 5-15 Parts of thermoplastic polyurethane, 1-5 Parts of a toughening agent, 0.1 To 0.5 part of tetrapentaerythritol ester antioxidant, 1-3 Parts of POE-g-MAH compatilizer; the release coating comprises the following components in parts by mass: 30-50 parts of organic silicon release agent, 10-20 Parts of wear-resistant auxiliary agent, 2-5 Parts of a cross-linking agent, 0.1 To 0.5 part of catalyst, 2-5 Parts of ethoxypolysilazane, 80-120 Parts of a solvent; the wear-resistant auxiliary agent comprises polytetrafluoroethylene micropowder and organic surface modified boron nitride, The solvent is a mixed solvent of ethyl acetate and isopropanol.
2. 2. The scratch-resistant release film according to claim 1, wherein the mass ratio of the polytetrafluoroethylene micro powder to the organic surface modified boron nitride is (1-2): 1.
3. 3. The scratch resistant release film of claim 1 wherein said toughening agent is a methyl methacrylate-butadiene-styrene copolymer.
4. 4. The scratch resistant release film of claim 1 wherein said organic surface modified boron nitride is vinyl modified boron nitride.
5. 5. The scratch resistant release film of claim 4, wherein the vinyl modified boron nitride is modified with a vinyl triethoxysilane coupling agent.
6. 6. The scratch resistant release film of claim 1 wherein said cross-linking agent is polymethylhydrosiloxane.
7. 7. The scratch resistant release film of claim 1 wherein said catalyst is a delayed platinum catalyst.
8. 8. A method for preparing the scratch-resistant release film according to any one of claims 1 to 7, comprising the following steps: S1, mixing PET resin, thermoplastic polyurethane, a toughening agent, a tetrapentaerythritol ester antioxidant and a POE-g-MAH compatilizer to obtain a premix, feeding the premix into a double-screw extruder, extruding, casting to form a film, stretching and shaping, and cooling to obtain a modified PET substrate; s2, adding an organosilicon release agent, an abrasion-resistant auxiliary agent, a crosslinking agent, a catalyst and ethoxypolysilazane into the mixed solvent, stirring and dispersing to obtain release coating liquid; And S3, coating the release coating liquid on one side of the modified PET substrate, and curing and forming the coated substrate.

Description

Scratch-resistant release film and preparation method thereof Technical Field The application relates to the technical field of functional film materials, in particular to a scratch-resistant release film and a preparation method thereof. Background The release film is used as a functional protective material, and is widely used for temporary protection of automobiles and electronic products by virtue of the peelability and the surface smoothness of the release film. The existing release film takes polyethylene terephthalate (PET) as a base material, and forms a low surface energy coating by coating an organosilicon, a fluorine or a non-silicon release agent on the surface. Among them, the silicone release film occupies the mainstream market by virtue of excellent release force stability and temperature resistance, and its coating is realized by solvent-based or solvent-free process, the latter becoming an industry trend gradually due to environmental protection advantages. The fluorine release film is characterized by ultra-low surface energy and chemical corrosion resistance, but the application range is limited by higher cost. Non-silicone release systems are modified with acrylates or polyurethanes in an attempt to balance release properties with the residual gum rate, but long term temperature resistance is still inferior to silicone systems. However, the conventional release film is difficult to combine scratch resistance and high flexibility, the conventional release film generally adopts a mode of increasing the hardness of a coating or introducing inorganic fillers (such as silicon dioxide and aluminum oxide) in order to improve the scratch resistance, but the brittleness of the coating is increased, cracks and even falling off are easily generated under the action of bending or dynamic stress, otherwise, if the flexibility is enhanced by reducing the crosslinking degree of the coating or adding an elastomer, the hardness of the surface of the coating is reduced, and the scratch of a sharp object cannot be effectively resisted. Disclosure of Invention In order to solve the problem that the traditional release film is difficult to have scratch resistance and high flexibility, the scratch resistance release film and the preparation method thereof are provided. The above object of the present invention is achieved by the following technical solutions: a scratch-resistant release film comprises a substrate layer and a release coating, The substrate layer comprises the following components in parts by mass: 80-95 parts of PET resin, 5-15 Parts of thermoplastic polyurethane, 1-5 Parts of a toughening agent, 0.1 To 0.5 part of tetrapentaerythritol ester antioxidant, 1-3 Parts of POE-g-MAH compatilizer; The release coating comprises the following components in parts by mass: 30-50 parts of organic silicon release agent, 10-20 Parts of wear-resistant auxiliary agent, 2-5 Parts of a cross-linking agent, 0.1 To 0.5 part of catalyst, 2-5 Parts of ethoxypolysilazane, 80-120 Parts of a solvent; the wear-resistant auxiliary agent comprises polytetrafluoroethylene micropowder and organic surface modified boron nitride, The solvent is a mixed solvent of ethyl acetate and isopropanol. By adopting the technical scheme, the PET resin in the substrate layer is used as a main framework to provide rigidity, and the introduction of the thermoplastic polyurethane endows the substrate layer with toughness through a microphase separation structure formed by a soft segment in a molecular chain and PET forming part of the thermoplastic polyurethane; the toughening agent forms an elastic disperse phase in a PET matrix through a core-shell structure, external stress is absorbed through silver lines and a shearing band mechanism to inhibit crack growth, an anhydride group in the POE-g-MAH compatilizer reacts with a PET hydroxyl end group or a carboxyl group, meanwhile, a polyolefin chain segment of the POE-g-MAH compatilizer is compatible with TPU and the toughening agent to form strong interface combination, performance degradation caused by phase separation is avoided, the tetrapentaerythritol ester antioxidant inhibits oxidative degradation during high-temperature processing through capturing free radicals to maintain molecular chain integrity, the organic silicon release agent in the release coating has low surface energy to enable the surface to be smooth and non-sticky, polytetrafluoroethylene micro powder forms a lubricating layer on the surface of the coating through a low friction coefficient and a layered structure, the organic surface modified boron nitride is dispersed in an organic silicon network through the high hardness and the layered structure, scratch resistance is realized through physical blocking and stress dispersion, a main chain of ethoxypolysilazane takes Si-N bonds as a main chain, side chains contain organic groups such as ethoxy groups, hydrolysis reaction occurs to generate active silicon hydroxyl gr