PC composite material containing silica gel coating as well as preparation method and application of PC composite material

Abstract

The invention discloses a PC composite material containing a silica gel coating as well as a preparation method and application thereof, and the preparation method comprises the following steps: S1, prime coat treatment: uniformly coating a PC coiled material with an organic silicon adhesive, and after coating, carrying out curing treatment and cooling to obtain a prime coat; s2, preparation of a coating surface layer: uniformly coating release paper with a silica gel coating, and treating to reach a semi-vulcanized state to obtain the coating surface layer; s3, preparation of a coating laminating layer: uniformly coating the coating surface layer with a laminating layer substance to obtain the coating laminating layer; s4, stripping the release paper: covering one surface of the coating bonding layer on the release paper on the PC bottom coating, performing pressure shaping and baking treatment for complete vulcanization, and finally separating the release paper to obtain a semi-finished product; and S5, surface treatment: coating the surface layer of the coating of the semi-finished product with a mixed solvent, and carrying out baking treatment to obtain the product. The PC composite material prepared by the invention has the properties of excellent weather resistance, environment friendliness, no toxicity, aging resistance, ultraviolet resistance, easiness in cleaning and the like.

Description

Technical Field

[0001] The invention belongs to the technical field of new material preparation, and specifically relates to a PC composite material containing a silicone coating, a preparation method and an application thereof. Background Art

[0002] PC material, namely polycarbonate material, is an important engineering plastic, which is widely used in the fields of electronics, automobiles, construction, etc. PC material has the advantages of high mechanical strength, good heat resistance, good electrical insulation, good light transmittance, and environmental protection, so it plays an important role in the design of mobile devices such as mobile phones, cameras, and computer shells. With the continuous innovation of new materials, the application prospects of PC materials in the field of electronic information products are very broad.

[0003] In the prior art, Chinese patent document CN114634694A provides a PC material resistant to high temperature cooking and good processing, and a preparation method and application thereof. The PC material comprises the following components in parts by weight: 100 parts of polycarbonate, 0.3-1 parts of carbon black, and 0.1-1 parts of titanium dioxide. The synergistic combination of specific carbon black and titanium dioxide effectively improves the hydrolysis resistance and processing performance of the PC material under high temperature cooking conditions. The color difference of the obtained PC material resistant to high temperature cooking and good processing after treatment at 121°C for 96 hours is less than 10, and the impact performance retention rate is higher than 50%; however, it can be seen that it focuses on the performance of high temperature cooking resistance, and does not pay too much attention to other properties.

[0004] Chinese patent document CN112571905A provides a TPU / PC composite material and a preparation method and application thereof, comprising a PC board, an adhesive layer and a TPU layer from bottom to top; in parts by weight, the raw materials for preparing the adhesive layer include 80-95 parts of tackifying resin, 2-4 parts of curing agent and 0.5-1 part of leveling agent; the raw materials for preparing the TPU layer include 80-95 parts of TPU particles, 0.5-2 parts of plasticizer and 0.3-3 parts of flame retardant; the tackifying resin is water-based polyurethane resin and water-based rosin resin; the mass ratio of the water-based rosin resin to the water-based polyurethane resin is (0.2-0.6):1; the solid content of the water-based polyurethane resin is 40-50wt%, and the viscosity at 20°C is 6000-10000mPa.s; the softening point of the water-based rosin resin is 65-85°C, and the solid content is 45-60wt%. In the above technical solution, by limiting the specific raw materials for preparing the adhesive layer, not only can a good combination between the TPU layer and the PC board be achieved, but also the prepared composite material has excellent aging resistance, peel strength and folding fastness, and can be well applied to the back panel of mobile phones. It can be seen that the above-mentioned composite materials need to use two composite materials, TPU and PC, and the raw materials used are very specific, which limits the prospects for large-scale production and application.

[0005] Therefore, based on the above-mentioned deficiencies in the prior art, the present invention is proposed. Summary of the invention

[0006] In view of the shortcomings of the prior art, the purpose of the present invention is to provide a PC composite material containing a silicone coating and a preparation method and application thereof. The obtained PC composite material has excellent weather resistance, environmental protection and non-toxicity, anti-aging, anti-ultraviolet, easy cleaning and other properties.

[0007] In order to achieve the above object, the present invention adopts the following technical solution:

[0008] In a first aspect, the present invention provides a method for preparing a PC composite material containing a silica gel coating, comprising the following steps:

[0009] S1. Primer treatment: evenly apply silicone adhesive on the PC coil, and then perform curing treatment after coating, and cool to obtain a primer layer;

[0010] S2. Preparation of coating surface layer: evenly coating the release paper with silicone coating, treating at 75-85° C. to reach a semi-vulcanized state, and obtaining the coating surface layer;

[0011] S3, preparation of coating laminating layer: uniformly coating laminating layer material on the coating surface layer obtained in step S2 to obtain coating laminating layer;

[0012] S4, peeling off the release paper: Covering the coating laminating layer on the release paper on the PC base coating, pressure setting, baking treatment to fully vulcanize, and finally separating the release paper to obtain a semi-finished product;

[0013] S5. Surface treatment: Continue to apply the mixed solvent on the coating surface of the semi-finished product, and after baking treatment, a PC composite material is obtained.

[0014] In the above technical solution, the organic silicone adhesive, coating laminating layer, coating surface layer and surface layer are processed on the PC-based material in sequence, so as to give the PC composite material excellent comprehensive performance.

[0015] Preferably, in step S1, the preparation of the organic silicone adhesive comprises the following steps:

[0016] The hydrogen-containing polysiloxane, vinyl polysiloxane, dimethyldichlorosilane, octamethylcyclotetrasiloxane and platinum catalyst are mixed uniformly in weight proportions of 2-7 parts, 1-5 parts, 1-4 parts, 0.5-1.5 parts and 0.02-0.05 parts respectively, and then mixed with 4-8 parts of white spirit to obtain a product;

[0017] The coating amount of organic silicone adhesive is 30-40g / m 2 The curing temperature is 115-125°C and the curing time is 1-5 minutes.

[0018] Preferably, in step S2, the preparation of the silicone coating comprises the following steps: weighing the following raw materials in proportion by weight: 80 to 120 parts of methyl vinyl silicone rubber, 30 to 50 parts of reinforcing material, 2 to 8 parts of polyether modified polydimethylsiloxane, 5 to 12 parts of octamethylcyclotetrasiloxane, 0.2 to 1 part of organic peroxide, 1 to 5 parts of triethoxysilane, 1 to 2 parts of white spirit, 1 to 2 parts of decanate, 0.1 to 0.5 parts of platinum vulcanizing agent, 0.03 to 0.06 parts of tackifier, 0.1 to 0.3 parts of antistatic agent, 1.5 to 3.5 parts of fluff powder, 0.5 to 1 parts of matting powder, 0.08 to 0.2 parts of dispersant, and then mixing them evenly;

[0019] The coating amount of silicone coating is 80~120g / m 2 , the treatment time is 1 to 5 minutes at 75 to 85°C.

[0020] Preferably, the preparation of the reinforcing material comprises the following steps:

[0021] (1) Modification of rectorite: rectorite is mixed with sodium hydroxide and subjected to high temperature treatment. After the treatment, the mixture is crushed to obtain pre-modified rectorite;

[0022] (2) preparing chitosan acetic acid solution: adding chitosan to acetic acid solution, stirring and dispersing the chitosan evenly, and setting aside;

[0023] (3) Compounding with chitosan: adding the pre-modified rectorite obtained in step (1) to the chitosan acetic acid solution obtained in step (2), stirring, drying, grinding and sieving, to obtain modified rectorite;

[0024] (4) Modification of silica: Add silica to N,N-dimethylformamide, stir and disperse it evenly, then add succinic anhydride and KH550, then react under stirring and heating conditions, then centrifuge, wash and dry to obtain modified silica;

[0025] (5) The modified rectorite obtained in step (3) and the modified silicon dioxide obtained in step (4) are sequentially added into water, stirred, centrifuged, washed and dried to obtain a reinforcing material.

[0026] Preferably, in step (1), the mass ratio of rectorite to sodium hydroxide is 1:0.4-0.65, the high temperature treatment temperature is 780-805°C, and the treatment time is 0.5-4h;

[0027] In step (2), the concentration of the acetic acid solution is 0.5-1.2 wt %, and the concentration of the chitosan is 1.2-2.5 wt %;

[0028] In step (3), the mass ratio of pre-modified rectorite to chitosan is 8-12:1; the stirring treatment temperature is room temperature, the treatment time is 24-72 hours; the drying temperature is 105-110° C., and the sieve mesh number is 100-150 mesh;

[0029] In step (4), the heating temperature is 30-40° C., the heating treatment time is 0.5-6 h; the mass ratio of silicon dioxide, N,N-dimethylformamide, succinic anhydride, and KH550 is 1:40-75:2.5-5.5:3.5-6.5;

[0030] In step (5), the mass ratio of modified rectorite, modified silicon dioxide and water is 1-2:0.5-1:10; the stirring treatment temperature is 30-40°C, and the treatment time is 0.5-4h.

[0031] Preferably, in step S3, the preparation of the laminating layer material comprises the following steps: weighing the following raw materials in proportion by weight: 80 to 120 parts of methyl vinyl silicone rubber, 30 to 50 parts of fumed silica, 2 to 8 parts of polyether modified polydimethylsiloxane, 5 to 12 parts of hexamethylcyclotrisilazane, 0.2 to 1 part of organic peroxide, 1 to 5 parts of triethoxysilane, 1 to 2 parts of white spirit, 1 to 2 parts of decanate, 0.1 to 0.5 parts of platinum vulcanizing agent, 0.03 to 0.06 parts of tackifier, 0.5 to 1 parts of matting powder, and 0.08 to 0.2 parts of dispersant, and then mixing them evenly;

[0032] The coating amount of the laminating layer material is 100-120g / m 2 .

[0033] Preferably, in step S4, the baking treatment temperature is 100-110° C., and the baking treatment time is 1-5 min.

[0034] Preferably, in step S5, the mixed solvent is obtained by mixing the following raw materials by mass fraction: 45-55% dimethyl polysiloxane, 5-15% silicon dioxide, 25-35% decane, and 3-10% dimethyl silicone oil;

[0035] Coating amount is 30~35g / m 2 The baking temperature is 125-130°C and the baking time is 1-5 minutes.

[0036] In a second aspect, the present invention also provides a PC composite material prepared by the above method.

[0037] Correspondingly, the present invention also requests protection for the use of the above-prepared PC composite material in the production of mobile phone cases and mobile phone battery covers.

[0038] Compared with the prior art, the present invention has the following beneficial effects:

[0039] The PC composite material provided by the present invention uses a specific organic silicone adhesive and a silicone coating, so that the prepared PC composite material has excellent weather resistance, environmental protection, non-toxicity, anti-aging, UV resistance, easy cleaning and other properties; compared with the PU cloth base used in the traditional process (poor antifouling property, hydrolysis resistance, low manual bonding yield and shaping yield), the yield can be greatly improved and the production scale can be easily expanded.

[0040] The preparation method of the PC composite material provided by the present invention comprises primer treatment, laminating layer and surface layer treatment and surface treatment; wherein the primer is to apply adhesive on the PC base material, which is beneficial to the adhesion of the silicone coating; the laminating layer is beneficial to the adhesion with the organic silicone adhesive on the PC base material, and the surface layer gives the PC base material corresponding properties, the main film-forming components of the two are the same, and the types of functional substances are screened accordingly; the surface treatment provides the PC material with good smoothness and dust resistance, wear resistance and adhesion effects.

[0041] In the present invention, the adhesive component used in the primer can withstand boiling in 100° C. water for one hour without delamination after being cured by baking at 120° C., and has a good bonding effect.

[0042] In the present invention, the silicone coating has very good weather resistance, wear resistance, non-toxic and tasteless, and the added additives such as matting powder and antistatic agent can give the silicone coating excellent antistatic and matting properties, which can meet the use of projection screens; the reinforcing material used further improves the weather resistance and wear resistance of the silicone coating. Specifically, the reinforcing material uses rectorite, chitosan and silicon dioxide as the main materials. Silicon dioxide itself is a very good filler particle, which can effectively improve the anti-corrosion, wear resistance, tensile and compressive properties of the silicone coating, but it is easy to agglomerate and will not form after a large amount. The coating system is easy to thicken, so the use of rectorite is introduced in the present invention, which reduces the use cost of the reinforcing material on the one hand, and complements the advantages of silica on the other hand, and synergizes to achieve the greatest effect; and rectorite as a filler has poor compatibility between resins and poor dispersibility, so chitosan rich in hydroxyl, carboxyl and other groups is introduced in the present invention for modification to improve its compatibility with silica gel; of course, another purpose of introducing chitosan is to consider the use of silica, so as to facilitate the synergistic improvement of the performance of the silica gel coating with the modified silica. The reinforcing material provided in the present invention, during use, is carboxylated to silica, which is beneficial to increase its surface polarity and improve its compatibility with the resin, and the introduced carboxyl groups and some hydroxyl groups contained in it can be combined with the rectorite compounded with chitosan through hydrogen bonds and weak forces, which helps to form a large network system, densely filled between the resins, improve the film density of the silica gel coating, and then improve the overall performance of the silica gel coating. In addition, the present invention also performs high temperature treatment on the rectorite, which is beneficial to improve its activity and improve the combination with chitosan. In short, the rectorite and silicon dioxide provided by the present invention, based on the use of chitosan, an organic substance, maximize the improvement of the performance of the silica gel coating by the reinforcing material. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 This is a picture of the product obtained in Example 4. DETAILED DESCRIPTION

[0044] Embodiments of the present invention are described in detail below. All embodiments are exemplary and intended to be used to explain the present invention, but should not be construed as limiting the present invention.

[0045] Unless otherwise specified, the chemical reagents and production equipment involved in the present invention are purchased from the market.

[0046] The PC coils may be made of common materials on the market, such as STC-0025, which is purchased from Shenzhen Longgang Shuntaichang Plastic Co., Ltd.

[0047] Among them, organic silicone adhesive:

[0048] Hydrogen-containing polysiloxane, brand SH202, purchased from Hubei Longsheng Sihai New Materials Co., Ltd., with a hydrogen content of about 1.2;

[0049] Vinyl polysiloxane, brand DY-V401-5000, vinyl content 0.004 mol / 100 g, purchased from Shandong Dayi Chemical Co., Ltd.;

[0050] The platinum catalyst was 3% chloroplatinic acid isopropanol solution purchased from Dongguan Tianan Silica Gel Co., Ltd.

[0051] Among them, in the silicone coating:

[0052] Methyl vinyl silicone rubber, brand 112-2, purchased from Dongjue Silicone (Nanjing) Co., Ltd.;

[0053] Hexamethylcyclotrisilazane was purchased from Dongguan Beiteli New Materials Co., Ltd.

[0054] Polyether modified polydimethylsiloxane, brand SH204, purchased from Hubei Longsheng Sihai New Materials Co., Ltd.;

[0055] Organic peroxides, including dihydropropane peroxide, tert-butyl hydroperoxide, methyl ethyl ketone peroxide, etc., with the brand name TNOF-50M, were purchased from Dongguan Tianan Silica Gel Co., Ltd.;

[0056] Triethoxysilane, brand C8145, purchased from Dongguan Tianan Silica Gel Co., Ltd.;

[0057] Platinum curing agent, brand name TNA-25PS, purchased from Dongguan Tianan Silicone Co., Ltd.;

[0058] Tackifier, terpene-styrene resin, brand KH-792, purchased from Dongguan Dinghai Plastic Chemical Co., Ltd.;

[0059] Antistatic agent, made from chloride, silicone oil, polyvinyl alcohol and vinyl chloride, brand K-595, purchased from Hangzhou Lin'an Dechang Electrostatic Technology Co., Ltd.;

[0060] Fluff powder, made of acrylic acid and polyurethane, was purchased from Shenzhen Xingsheng Pearlescent Chemical Pigment Co., Ltd.;

[0061] Matting powder, made of silicon dioxide, silicate, and talc, was purchased from Shenzhen Xingsheng Pearlescent Chemical Pigment Co., Ltd.;

[0062] The dispersant was casein, purchased from Guangdong Zhongtai Lianhua New Materials Co., Ltd.

[0063] Among them, the bonding layer material:

[0064] Methyl vinyl silicone rubber, brand 112-2, purchased from Dongjue Silicone (Nanjing) Co., Ltd.;

[0065] Polyether modified polydimethylsiloxane, brand SH204, purchased from Hubei Longsheng Sihai New Materials Co., Ltd.;

[0066] Hexamethylcyclotrisilazane was purchased from Dongguan Beiteli New Materials Co., Ltd.

[0067] Organic peroxides, including dihydropropane peroxide, tert-butyl hydroperoxide, methyl ethyl ketone peroxide, etc., with the brand name TNOF-50M, were purchased from Dongguan Tianan Silica Gel Co., Ltd.;

[0068] Triethoxysilane, brand C8145, purchased from Dongguan Tianan Silica Gel Co., Ltd.;

[0069] Platinum curing agent, brand name TNA-25PS, purchased from Dongguan Tianan Silicone Co., Ltd.;

[0070] Tackifier, terpene-styrene resin, brand KH-792, purchased from Dongguan Dinghai Plastic Chemical Co., Ltd.;

[0071] Matting powder, made of silicon dioxide, silicate, and talc, was purchased from Shenzhen Xingsheng Pearlescent Chemical Pigment Co., Ltd.;

[0072] The dispersant was casein, purchased from Guangdong Zhongtai Lianhua New Materials Co., Ltd.

[0073] Among them, in the mixed solvent:

[0074] Dimethyl polysiloxane, brand WS-1115, purchased from Jiangxi Wuseshi New Materials Co., Ltd.;

[0075] Dimethyl silicone oil, with a viscosity of about 5000 mPa·s (25°C), was purchased from Hubei Longsheng Sihai New Materials Co., Ltd.

[0076] Silicon dioxide was purchased from Aladdin Technology Co., Ltd. with a particle size of about 50 nm.

[0077] Rectorite was purchased from Hubei Mingliu Rectorite Technology Co., Ltd.

[0078] The deacetylation degree of chitosan was about 85%, and it was purchased from Shandong Yatu Biotechnology Co., Ltd.

[0079] Example 1

[0080] A silicone coating, the preparation of which comprises the following steps: weighing the following substances by weight: 100g of methyl vinyl silicone rubber, 38g of reinforcing material, 5g of polyether modified polydimethylsiloxane, 8g of octamethylcyclotetrasiloxane, 0.5g of organic peroxide, 2g of triethoxysilane, 1g of white oil, 1g of decanter, 0.2g of platinum vulcanizer, 0.05g of tackifier, 0.1g of antistatic agent, 3g of fluff powder, 0.8g of matting powder, 0.01g of dispersant, and then mixing them evenly.

[0081] Wherein, the preparation of the reinforcing material comprises the following steps:

[0082] (1) Modification of rectorite: rectorite and sodium hydroxide were mixed in a mass ratio of 1:0.5 and then subjected to high temperature treatment (795°C, 1 h). After the treatment, the mixture was crushed to obtain pre-modified rectorite;

[0083] (2) preparing chitosan acetic acid solution: adding chitosan to 1 wt % acetic acid solution to make the concentration of chitosan 2 wt %, stirring and dispersing the solution evenly, and setting aside;

[0084] (3) Compounding with chitosan: the pre-modified rectorite obtained in step (1) was added to the chitosan acetic acid solution obtained in step (2) at a mass ratio of pre-modified rectorite to chitosan of 10:1, and the mixture was stirred (room temperature, 48 h), dried (105° C., 2 h), and ground and sieved through 150 mesh to obtain modified rectorite;

[0085] (4) Modification of silica: Add silica to N,N-dimethylformamide, stir and disperse it evenly, then add succinic anhydride and KH550, and then react under stirring and heating conditions (35°C, 2.5h), then centrifuge, wash and dry to obtain modified silica; wherein the mass ratio of silica, N,N-dimethylformamide, succinic anhydride and KH550 is 1:50:4:4.5;

[0086] (5) The modified rectorite obtained in step (3) and the modified silica obtained in step (4) are added to water in a mass ratio of 1.2:0.6:8, stirred (35°C, 2.5h), centrifuged, washed and dried to obtain a reinforcing material.

[0087] Example 2

[0088] A silicone coating, the preparation of which comprises the following steps: weighing the following substances by weight: 95g of methyl vinyl silicone rubber, 40g of reinforcing material, 3.5g of polyether modified polydimethylsiloxane, 7.5g of octamethylcyclotetrasiloxane, 0.5g of organic peroxide, 2g of triethoxysilane, 0.9g of white oil, 1.1g of decanter, 0.2g of platinum vulcanizer, 0.05g of tackifier, 0.1g of antistatic agent, 3g of fluff powder, 0.8g of matting powder, 0.01g of dispersant, and then mixing them evenly.

[0089] Wherein, the preparation of the reinforcing material comprises the following steps:

[0090] (1) Modification of rectorite: rectorite and sodium hydroxide were mixed in a mass ratio of 1:0.45 and then subjected to high temperature treatment (795°C, 1 h). After the treatment, the mixture was crushed to obtain pre-modified rectorite;

[0091] (2) preparing chitosan acetic acid solution: adding chitosan to 0.9 wt % acetic acid solution to make the concentration of chitosan 1.8 wt %, stirring and dispersing the mixture evenly, and setting aside;

[0092] (3) Compounding with chitosan: According to the mass ratio of pre-modified rectorite to chitosan of 9.5:1, the pre-modified rectorite obtained in step (1) was added to the chitosan acetic acid solution obtained in step (2), stirred (room temperature, 48 h), dried (105° C., 2 h) and ground and sieved through 150 mesh to obtain modified rectorite;

[0093] (4) Modification of silica: Add silica to N,N-dimethylformamide, stir and disperse it evenly, then add succinic anhydride and KH550, and then react under stirring and heating conditions (35°C, 2.5h), then centrifuge, wash and dry to obtain modified silica; wherein the mass ratio of silica, N,N-dimethylformamide, succinic anhydride and KH550 is 1:50:4.2:4.8;

[0094] (5) The modified rectorite obtained in step (3) and the modified silica obtained in step (4) are added to water in a mass ratio of 1.2:0.6:8, stirred (35°C, 2.5h), centrifuged, washed and dried to obtain a reinforcing material.

[0095] Example 3

[0096] A silicone coating, the preparation of which comprises the following steps: weighing the following substances by weight: 105g of methyl vinyl silicone rubber, 37g of reinforcing material, 4.8g of polyether modified polydimethylsiloxane, 8g of octamethylcyclotetrasiloxane, 0.5g of organic peroxide, 2g of triethoxysilane, 1.1g of white spirit, 1.9g of decanter, 0.2g of platinum vulcanizer, 0.05g of tackifier, 0.1g of antistatic agent, 3g of fluff powder, 0.8g of matting powder, 0.01g of dispersant, and then mixing them evenly.

[0097] Wherein, the preparation of the reinforcing material comprises the following steps:

[0098] (1) Modification of rectorite: rectorite and sodium hydroxide were mixed in a mass ratio of 1:0.52 and then subjected to high temperature treatment (795°C, 1 h). After the treatment, the mixture was crushed to obtain pre-modified rectorite;

[0099] (2) preparing chitosan acetic acid solution: adding chitosan to 0.95 wt % acetic acid solution to make the concentration of chitosan 1.9 wt %, stirring and dispersing the solution evenly, and setting aside;

[0100] (3) Compounding with chitosan: According to the mass ratio of pre-modified rectorite to chitosan of 10.5:1, the pre-modified rectorite obtained in step (1) was added to the chitosan acetic acid solution obtained in step (2), stirred (room temperature, 48 h), dried (105° C., 2 h) and ground and sieved through 150 mesh to obtain modified rectorite;

[0101] (4) Modification of silica: Add silica to N,N-dimethylformamide, stir and disperse it evenly, then add succinic anhydride and KH550, and then react under stirring and heating conditions (35°C, 3h), then centrifuge, wash and dry to obtain modified silica; wherein the mass ratio of silica, N,N-dimethylformamide, succinic anhydride and KH550 is 1:50:4.2:4.8;

[0102] (5) The modified rectorite obtained in step (3) and the modified silica obtained in step (4) are added to water in a mass ratio of 1.2:0.65:8, stirred (35°C, 2.5h), centrifuged, washed and dried to obtain a reinforcing material.

[0103] Example 4

[0104] A method for preparing a PC composite material containing a silicone coating comprises the following steps:

[0105] S1. Primer treatment: evenly apply silicone adhesive on the PC coil (coating amount is 35g / m 2), after coating, curing treatment (120°C, 3min) is performed, followed by cooling to obtain a primer layer;

[0106] S2. Preparation of coating surface layer: The silicone coating prepared in Example 1 was evenly coated on the release paper (coating amount was 90 g / m 2 ), treated at 80°C to reach a semi-vulcanized state, to obtain a coating surface layer;

[0107] S3, preparation of coating laminating layer: uniformly coat the laminating layer material (coating amount is 110 g / m 2 ), to obtain a coating bonding layer;

[0108] S4, peeling of release paper: Cover one side of the coating laminating layer on the release paper on the PC base coating, and perform pressure shaping and baking treatment (100°C, 3min) by a 80kg heavy round pressure wheel and a 2.5KG cylinder pressure to completely vulcanize, and finally separate the release paper to obtain a semi-finished product;

[0109] S5. Surface treatment: Continue to apply mixed solvent on the coating surface of the semi-finished product (coating amount is 30g / m 2 ), and after baking treatment (130℃, 3min), the PC composite material was obtained.

[0110] The preparation of the organic silicone adhesive comprises the following steps:

[0111] Evenly mix 6g of hydrogen-containing polysiloxane, 3g of vinyl polysiloxane, 2g of dimethyldichlorosilane, 1g of octamethylcyclotetrasiloxane and 0.05g of platinum catalyst, and then mix with 6g of white oil to obtain the product.

[0112] The mixed solvent is obtained by mixing the following raw materials in mass fractions: 50% dimethyl polysiloxane, 8% silicon dioxide, 37% decane, and 5% dimethyl silicone oil.

[0113] Among them, the preparation of the bonding layer material includes the following steps: weigh the following weight portions of the preparation raw materials in proportion: 100g methyl vinyl silicone rubber, 45g fumed silica, 5g polyether modified polydimethylsiloxane, 10g hexamethylcyclotrisilazane, 0.5g organic peroxide, 2g triethoxysilane, 1.5g white oil, 1.5g decanate, 0.2g platinum vulcanizer, 0.05g tackifier, 0.8g matting powder, 0.1g dispersant, and then mix them evenly.

[0114] Example 5

[0115] A method for preparing a PC composite material containing a silicone coating comprises the following steps:

[0116] S1. Primer treatment: evenly apply silicone adhesive on the PC coil (coating amount is 35g / m 2 ), after coating, curing treatment (120°C, 3min) is performed, followed by cooling to obtain a primer layer;

[0117] S2. Preparation of coating surface layer: The silicone coating prepared in Example 2 was evenly coated on the release paper (coating amount was 90 g / m 2 ), treated at 80°C to reach a semi-vulcanized state, to obtain a coating surface layer;

[0118] S3, preparation of coating laminating layer: uniformly coat the laminating layer material (coating amount is 110 g / m 2 ), to obtain a coating bonding layer;

[0119] S4, peeling of release paper: Cover one side of the coating laminating layer on the release paper on the PC base coating, and perform pressure shaping and baking treatment (100°C, 3min) by a 80kg heavy round pressure wheel and a 2.5KG cylinder pressure to completely vulcanize, and finally separate the release paper to obtain a semi-finished product;

[0120] S5. Surface treatment: Continue to apply mixed solvent on the coating surface of the semi-finished product (coating amount is 30g / m 2 ), and after baking treatment (130℃, 3min), the PC composite material was obtained.

[0121] The preparation of the organic silicone adhesive comprises the following steps:

[0122] Evenly mix 6g of hydrogen-containing polysiloxane, 3g of vinyl polysiloxane, 2g of dimethyldichlorosilane, 1g of octamethylcyclotetrasiloxane and 0.05g of platinum catalyst, and then mix with 6g of white oil to obtain the product.

[0123] The mixed solvent is obtained by mixing the following raw materials in mass fractions: 50% dimethyl polysiloxane, 8% silicon dioxide, 37% decane, and 5% dimethyl silicone oil.

[0124] Among them, the preparation of the bonding layer material includes the following steps: weigh the following weight portions of the preparation raw materials in proportion: 100g methyl vinyl silicone rubber, 45g fumed silica, 5g polyether modified polydimethylsiloxane, 10g hexamethylcyclotrisilazane, 0.5g organic peroxide, 2g triethoxysilane, 1.5g white oil, 1.5g decanate, 0.2g platinum vulcanizer, 0.05g tackifier, 0.8g matting powder, 0.1g dispersant, and then mix them evenly.

[0125] Example 6

[0126] A method for preparing a PC composite material containing a silicone coating comprises the following steps:

[0127] S1. Primer treatment: evenly apply silicone adhesive on the PC coil (coating amount is 35g / m 2 ), after coating, curing treatment (120°C, 3min) is performed, followed by cooling to obtain a primer layer;

[0128] S2. Preparation of coating surface layer: The silicone coating prepared in Example 3 was evenly coated on the release paper (coating amount was 90 g / m 2 ), treated at 80°C to reach a semi-vulcanized state, to obtain a coating surface layer;

[0129] S3, preparation of coating laminating layer: uniformly coat the laminating layer material (coating amount is 110 g / m 2 ), to obtain a coating bonding layer;

[0130] S4, peeling of release paper: Cover one side of the coating laminating layer on the release paper on the PC base coating, and perform pressure shaping and baking treatment (100°C, 3min) by a 80kg heavy round pressure wheel and a 2.5KG cylinder pressure to completely vulcanize, and finally separate the release paper to obtain a semi-finished product;

[0131] S5. Surface treatment: Continue to apply mixed solvent on the coating surface of the semi-finished product (coating amount is 30g / m 2 ), and after baking treatment (130℃, 3min), the PC composite material was obtained.

[0132] The preparation of the organic silicone adhesive comprises the following steps:

[0133] Evenly mix 6g of hydrogen-containing polysiloxane, 3g of vinyl polysiloxane, 2g of dimethyldichlorosilane, 1g of octamethylcyclotetrasiloxane and 0.05g of platinum catalyst, and then mix with 6g of white oil to obtain the product.

[0134] The mixed solvent is obtained by mixing the following raw materials in mass fractions: 50% dimethyl polysiloxane, 8% silicon dioxide, 37% decane, and 5% dimethyl silicone oil.

[0135] Among them, the preparation of the bonding layer material includes the following steps: weigh the following weight portions of the preparation raw materials in proportion: 100g methyl vinyl silicone rubber, 45g fumed silica, 5g polyether modified polydimethylsiloxane, 10g hexamethylcyclotrisilazane, 0.5g organic peroxide, 2g triethoxysilane, 1.5g white oil, 1.5g decanate, 0.2g platinum vulcanizer, 0.05g tackifier, 0.8g matting powder, 0.1g dispersant, and then mix them evenly.

[0136] Comparative Example 1

[0137] Compared with Example 1, Comparative Example 1 omits the pretreatment of rectorite. Specifically, in Comparative Example 1, a silicone coating is prepared by the following steps: weigh the following substances by weight: 100g methyl vinyl silicone rubber, 38g reinforcing material, 5g polyether modified polydimethylsiloxane, 8g octamethylcyclotetrasiloxane, 0.5g organic peroxide, 2g triethoxysilane, 1g white oil, 1g decanter, 0.2g platinum vulcanizer, 0.05g tackifier, 0.1g antistatic agent, 3g fluff powder, 0.8g matting powder, 0.01g dispersant, and then mix them evenly.

[0138] Wherein, the preparation of the reinforcing material comprises the following steps:

[0139] (1) taking a rectorite raw material, crushing it and setting it aside;

[0140] (2) preparing chitosan acetic acid solution: adding chitosan to 1 wt % acetic acid solution to make the concentration of chitosan 2 wt %, stirring and dispersing the solution evenly, and setting aside;

[0141] (3) Compounding with chitosan: According to the mass ratio of rectorite to chitosan of 10:1, the rectorite obtained in step (1) was added to the chitosan acetic acid solution obtained in step (2), stirred (room temperature, 48 h), dried (105° C., 2 h) and ground and sieved through 150 mesh to obtain modified rectorite;

[0142] (4) Modification of silica: Add silica to N,N-dimethylformamide, stir and disperse it evenly, then add succinic anhydride and KH550, and then react under stirring and heating conditions (35°C, 2.5h), then centrifuge, wash and dry to obtain modified silica; wherein the mass ratio of silica, N,N-dimethylformamide, succinic anhydride and KH550 is 1:50:4:4.5;

[0143] (5) The modified rectorite obtained in step (3) and the modified silica obtained in step (4) are added to water in a mass ratio of 1.2:0.6:8, stirred (35°C, 2.5h), centrifuged, washed and dried to obtain a reinforcing material.

[0144] The preparation of the silica gel coating comprises the following steps: taking various substances by weight and mixing them evenly.

[0145] Comparative Example 2

[0146] Compared with Example 1, the modification treatment of chitosan is omitted in Comparative Example 2. Specifically, in Comparative Example 2, a silicone coating is prepared by the following steps: weigh the following substances by weight: 100g methyl vinyl silicone rubber, 38g reinforcing material, 5g polyether modified polydimethylsiloxane, 8g octamethylcyclotetrasiloxane, 0.5g organic peroxide, 2g triethoxysilane, 1g white oil, 1g decanter, 0.2g platinum vulcanizer, 0.05g tackifier, 0.1g antistatic agent, 3g fluff powder, 0.8g matting powder, 0.01g dispersant, and then mix them evenly.

[0147] Wherein, the preparation of the reinforcing material comprises the following steps:

[0148] (1) Modification of rectorite: rectorite and sodium hydroxide were mixed in a mass ratio of 1:0.5 and then subjected to high temperature treatment (795°C, 1 h). After the treatment, the mixture was crushed to obtain pre-modified rectorite;

[0149] (2) Modification of silica: Add silica to N,N-dimethylformamide, stir and disperse it evenly, then add succinic anhydride and KH550, and then react under stirring and heating conditions (35°C, 2.5h), then centrifuge, wash and dry to obtain modified silica; wherein the mass ratio of silica, N,N-dimethylformamide, succinic anhydride and KH550 is 1:50:4:4.5;

[0150] (3) The pre-modified rectorite obtained in step (1) and the modified silica obtained in step (2) are added to water in a mass ratio of 1.2:0.6:8, stirred (35°C, 2.5h), centrifuged, washed and dried to obtain a reinforcing material.

[0151] The preparation of the silica gel coating comprises the following steps: taking various substances by weight and mixing them evenly.

[0152] Comparative Example 3

[0153] Compared with Example 1, Comparative Example 3 omits the modification treatment of silica. Specifically, in Comparative Example 3, a silicone coating is prepared by the following steps: weigh the following substances by weight: 100g methyl vinyl silicone rubber, 38g reinforcing material, 5g polyether modified polydimethylsiloxane, 8g octamethylcyclotetrasiloxane, 0.5g organic peroxide, 2g triethoxysilane, 1g white oil, 1g decanter, 0.2g platinum vulcanizer, 0.05g tackifier, 0.1g antistatic agent, 3g fluff powder, 0.8g matting powder, 0.01g dispersant, and then mix them evenly.

[0154] Wherein, the preparation of the reinforcing material comprises the following steps:

[0155] (1) Modification of rectorite: rectorite and sodium hydroxide were mixed in a mass ratio of 1:0.5 and then subjected to high temperature treatment (795°C, 1 h). After the treatment, the mixture was crushed to obtain pre-modified rectorite;

[0156] (2) preparing chitosan acetic acid solution: adding chitosan to 1 wt % acetic acid solution to make the concentration of chitosan 2 wt %, stirring and dispersing the solution evenly, and setting aside;

[0157] (3) Compounding with chitosan: the pre-modified rectorite obtained in step (1) was added to the chitosan acetic acid solution obtained in step (2) at a mass ratio of pre-modified rectorite to chitosan of 10:1, and the mixture was stirred (room temperature, 48 h), dried (105° C., 2 h), and ground and sieved through 150 mesh to obtain modified rectorite;

[0158] (4) taking silicon dioxide and setting aside;

[0159] (5) The modified rectorite obtained in step (3) and the silicon dioxide obtained in step (4) are added to water in a mass ratio of 1.2:0.6:8, stirred (35°C, 2.5h), centrifuged, washed and dried to obtain a reinforcing material.

[0160] The preparation of the silica gel coating comprises the following steps: taking various substances by weight and mixing them evenly.

[0161] The performance test of the silicone coatings prepared in Example 1 and Comparative Examples 1 to 3 was carried out as follows:

[0162] The wear resistance is carried out in accordance with GB / T1768-2006. After the coating is applied, it is first treated at 80°C for 2 minutes and then at 130°C for 3 minutes.

[0163] Weather resistance is carried out according to ISO20340-2009.

[0164] Corrosion resistance test: soak in 6% sodium hydroxide first, then accelerate corrosion test at 35℃.

[0165] The test results are shown in Table 1.

[0166] Table 1

[0167]

[0168] It can be seen from Table 1 that the silica gel coating prepared by the present invention has good wear resistance, corrosion resistance and weather resistance.

[0169] The PC composite material prepared in Example 4 was tested for performance, and the test results are shown in Table 2.

[0170] Table 2 Example 4 Material Test Results

[0171]

[0172]

[0173] It can be seen from Table 2 that the PC composite material prepared by the present invention has good comprehensive performance and is very suitable for the production of mobile phone shells and mobile phone battery covers.

[0174] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for preparing a PC composite material containing a silicone coating, characterized in that: The steps include: S1. Primer treatment: evenly apply silicone adhesive on the PC coil, and then perform curing treatment after coating, and cool to obtain a primer layer; S2. Preparation of coating surface layer: evenly coating the release paper with silicone coating, treating at 75-85° C. to reach a semi-vulcanized state, and obtaining the coating surface layer; S3, preparation of coating laminating layer: uniformly coating laminating layer material on the coating surface layer obtained in step S2 to obtain coating laminating layer; S4, peeling off the release paper: Covering the coating laminating layer on the release paper on the PC base coating, pressure setting, baking treatment to fully vulcanize, and finally separating the release paper to obtain a semi-finished product; S5. Surface treatment: Continue to apply the mixed solvent on the coating surface of the semi-finished product, and after baking treatment, a PC composite material is obtained.

2. The method for preparing a PC composite material containing a silicone coating according to claim 1, characterized in that: In step S1, the preparation of the organic silicone adhesive comprises the following steps: The hydrogen-containing polysiloxane, vinyl polysiloxane, dimethyldichlorosilane, octamethylcyclotetrasiloxane and platinum catalyst are mixed uniformly in weight proportions of 2-7 parts, 1-5 parts, 1-4 parts, 0.5-1.5 parts and 0.02-0.05 parts respectively, and then mixed with 4-8 parts of white spirit to obtain a product; The coating amount of organic silicone adhesive is 30-40g / m 2 The curing temperature is 115-125°C and the curing time is 1-5 minutes.

3. The method for preparing a PC composite material containing a silicone coating according to claim 1, characterized in that: In step S2, the preparation of the silicone coating comprises the following steps: weighing the following raw materials in proportion by weight: 80 to 120 parts of methyl vinyl silicone rubber, 30 to 50 parts of reinforcing material, 2 to 8 parts of polyether modified polydimethylsiloxane, 5 to 12 parts of octamethylcyclotetrasiloxane, 0.2 to 1 part of organic peroxide, 1 to 5 parts of triethoxysilane, 1 to 2 parts of white spirit, 1 to 2 parts of decanate, 0.1 to 0.5 parts of platinum vulcanizing agent, 0.03 to 0.06 parts of tackifier, 0.1 to 0.3 parts of antistatic agent, 1.5 to 3.5 parts of fluff powder, 0.5 to 1 parts of matting powder, 0.08 to 0.2 parts of dispersant, and then mixing them evenly; The coating amount of silicone coating is 80~100g / m 2 , the treatment time is 1 to 5 minutes at 75 to 85°C.

4. The method for preparing a PC composite material containing a silicone coating according to claim 3, characterized in that: The preparation of the reinforcing material comprises the following steps: (1) Modification of rectorite: rectorite is mixed with sodium hydroxide and subjected to high temperature treatment. After the treatment, the mixture is crushed to obtain pre-modified rectorite; (2) preparing chitosan acetic acid solution: adding chitosan to acetic acid solution, stirring and dispersing the chitosan evenly, and setting aside; (3) Compounding with chitosan: adding the pre-modified rectorite obtained in step (1) to the chitosan acetic acid solution obtained in step (2), stirring, drying, grinding and sieving, to obtain modified rectorite; (4) Modification of silica: Add silica to N,N-dimethylformamide, stir and disperse it evenly, then add succinic anhydride and KH550, then react under stirring and heating conditions, then centrifuge, wash and dry to obtain modified silica; (5) The modified rectorite obtained in step (3) and the modified silicon dioxide obtained in step (4) are sequentially added into water, stirred, centrifuged, washed and dried to obtain a reinforcing material.

5. The method for preparing a PC composite material containing a silicone coating according to claim 4, characterized in that: In step (1), the mass ratio of rectorite to sodium hydroxide is 1:0.4-0.65, the high temperature treatment temperature is 780-805°C, and the treatment time is 0.5-4h; In step (2), the concentration of the acetic acid solution is 0.5-1.2 wt %, and the concentration of the chitosan is 1.2-2.5 wt %; In step (3), the mass ratio of pre-modified rectorite to chitosan is 8-12:1; the stirring treatment temperature is room temperature, the treatment time is 24-72 hours; the drying temperature is 105-110° C., and the sieve mesh number is 100-150 mesh; In step (4), the heating temperature is 30-40° C., the heating treatment time is 0.5-6 h; the mass ratio of silicon dioxide, N,N-dimethylformamide, succinic anhydride, and KH550 is 1:40-75:2.5-5.5:3.5-6.5; In step (5), the mass ratio of modified rectorite, modified silicon dioxide and water is 1-2:0.5-1:10; the stirring treatment temperature is 30-40°C, and the treatment time is 0.5-4h.

6. The method for preparing a PC composite material containing a silicone coating according to claim 2, characterized in that: In step S3, the preparation of the laminating layer material comprises the following steps: weighing the following raw materials in proportion by weight: 80 to 120 parts of methyl vinyl silicone rubber, 30 to 50 parts of fumed silica, 2 to 8 parts of polyether modified polydimethylsiloxane, 5 to 12 parts of hexamethylcyclotrisilazane, 0.2 to 1 part of organic peroxide, 1 to 5 parts of triethoxysilane, 1 to 2 parts of white oil, 1 to 2 parts of decanate, 0.1 to 0.5 parts of platinum vulcanizing agent, 0.03 to 0.06 parts of tackifier, 0.5 to 1 parts of matting powder, and 0.08 to 0.2 parts of dispersant, and then mixing them evenly; The coating amount of the laminating layer material is 100-120g / m 2 .

7. The method for preparing a PC composite material containing a silicone coating according to claim 2, characterized in that: In step S4, the baking treatment temperature is 100-110° C., and the baking treatment time is 1-5 minutes.

8. The method for preparing a PC composite material containing a silicone coating according to claim 2, characterized in that: In step S5, the mixed solvent is obtained by mixing the following raw materials by mass fraction: 45-55% dimethyl polysiloxane, 5-15% silicon dioxide, 25-35% decane, and 3-10% dimethyl silicone oil; Coating amount is 30~35g / m 2 The baking temperature is 125-130°C and the baking time is 1-5 minutes.

9. A PC composite material prepared by the method according to any one of claims 1 to 8.

10. Use of the PC composite material according to claim 9 in the production of mobile phone shells and mobile phone battery covers. The baking temperature is 125-135°C and the baking time is 1-5 minutes.

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