High-transparency impact-resistant film material and preparation method thereof

Abstract

The invention discloses a high-transparency impact-resistant membrane material and a preparation method thereof, and belongs to the technical field of membrane materials. Comprising the following raw materials in parts by weight: 80-90 parts of polycarbonate resin, 4-8 parts of an antioxidant, 5-15 parts of a modifier, 3-5 parts of an anti-dripping agent and 1-4 parts of a processing aid. The prepared membrane material takes polycarbonate as a matrix, so that the membrane material is endowed with excellent impact resistance and transparency; the added antioxidant can play a synergistic role, so that the oxidation resistance of the membrane material is enhanced; the modifier is prepared through a series of reactions, molecules of the modifier contain functional groups, the flame retardance, ultraviolet resistance and impact resistance of the membrane material can be improved, and the stability is good; therefore, the prepared membrane material is good in mechanical property and high in transparency, has excellent impact resistance, flame retardance and ultraviolet resistance, and has important application value in the technical field of membrane materials.

Description

Technical Field

[0001] The present invention belongs to the technical field of film materials, and in particular, relates to a highly transparent and impact-resistant film material and a preparation method thereof. Background Art

[0002] In recent years, the automotive industry has developed rapidly. In addition to the increasing requirements for car driving, people also have higher demands for car window films. Car window films can not only increase the firmness of car windows and prevent them from being easily broken in unexpected situations, but also dark window films can effectively create a private space and prevent the outside world from interfering with the situation inside the car.

[0003] Polycarbonate is a high-performance thermoplastic polymer with excellent mechanical properties and heat resistance. The transmittance of visible light can reach more than 90%, and it has extremely strong impact resistance, which is 250 times that of glass and 30 times that of acrylic plate. It can bond fragments when glass breaks to reduce damage to passengers. It is a newer automotive window film material. Due to its excellent performance, polycarbonate film is often used in high-end car window films.

[0004] After long-term exposure to the sun, the ultraviolet radiation in the sunlight of polycarbonate car window film will cause the car paint to fade, and the paint protective film will also turn yellow and age. In addition, polycarbonate has a low oxygen index and poor flame retardant properties, which greatly limits the application of polycarbonate car window film. Therefore, the above problems need to be solved to meet higher demands in the field of film material technology. Summary of the invention

[0005] The purpose of the present invention is to overcome the defects of the prior art and provide a highly transparent impact-resistant film material and a preparation method thereof.

[0006] The purpose of the present invention can be achieved through the following technical solutions: A method for preparing a highly transparent impact-resistant film material comprises the following steps: The polycarbonate resin, antioxidant, modifier and anti-dripping agent are dried; the dried polycarbonate resin is stirred in a high-speed mixer at a speed of 300-400 rpm for 1-3 minutes, and then the antioxidant, modifier, anti-dripping agent and processing aid are added, and the stirring is continued for 4-8 minutes, and the obtained mixture is sent to a twin-screw extruder with a speed of 200-300 rpm, melt-extruded, granulated, and the obtained masterbatch is blow-molded by a molding machine to obtain a high-transparency impact-resistant film material.

[0007] Furthermore, the raw materials are calculated in parts by weight as follows: 80-90 parts of polycarbonate resin, 4-8 parts of antioxidant, 5-15 parts of modifier, 3-5 parts of anti-drip agent, and 1-4 parts of processing aid.

[0008] Furthermore, the polycarbonate resin is an aromatic polycarbonate resin.

[0009] Furthermore, the antioxidant is prepared by compounding a hindered phenol antioxidant and a phosphite antioxidant in a mass ratio of 3:1.

[0010] Furthermore, the anti-drip agent is one of a polytetrafluoroethylene anti-drip agent and a silicone anti-drip agent.

[0011] Furthermore, the processing aid is one or more of paraffin, stearic acid, calcium stearate and zinc stearate.

[0012] The membrane material is based on polycarbonate, which gives the membrane material excellent impact resistance and transparency. The added anti-dripping agent can enhance the flame retardant properties of the membrane material; the added processing aid can improve the processing stability. Finally, the added antioxidants are hindered phenol antioxidants and phosphite auxiliary antioxidants, which can play a synergistic role and greatly enhance the antioxidant properties of the membrane material.

[0013] Furthermore, the modifier is prepared by the following steps: A1. Add pentaerythritol and boric acid into a three-necked flask equipped with a thermometer and an oil-water separator, place the device on an electric stirrer, add toluene as a water-carrying agent, heat to 115°C, stir and reflux until water is no longer generated, keep the temperature constant, and continue the reaction for 3 hours. After the reaction is completed, remove toluene by vacuum distillation to obtain intermediate product 1; the ratio of pentaerythritol, boric acid and toluene is 13.6g:12.4g:100mL; Pentaerythritol and boric acid undergo esterification reaction, and the molar ratio of the two is controlled to be 1:2; toluene is selected as a water-carrying agent to remove the generated water from the reaction system, promote the reaction, and obtain the intermediate product 1; the specific reaction process is as follows:

[0014] A2. Add cyanuric chloride, resorcinol and toluene into a three-necked flask equipped with a thermometer and a stirring device, mix and stir continuously, then add aluminum chloride (catalyst), control the reaction temperature to 65°C, stir continuously during the reaction, react for 6 hours, the reaction is completed, filter, remove toluene by steam distillation, filter again, wash with anhydrous ethanol 2-3 times, and dry in an oven to obtain intermediate product 2; the ratio of cyanuric chloride, resorcinol, toluene and aluminum chloride is 19.1g:21.8g:150mL:7.4g; Under the catalysis of aluminum chloride, cyanuric chloride and resorcinol undergo an alkylation reaction. By controlling the molar ratio of the two to be close to 1:2 and a slight excess of cyanuric chloride, only two chlorine groups on cyanuric chloride participate in the reaction to obtain an intermediate product 2. The specific reaction process is as follows:

[0015] A3. Add intermediate product 1, intermediate product 2 and N,N-dimethylformamide (DMF) into a three-necked flask equipped with a thermometer and a stirring device; control the reaction temperature to 70°C, stir continuously during the reaction, and adjust the pH to neutral with sodium carbonate solution, keep the reaction for 8 hours, filter after the reaction is completed, and dry to obtain a modifier; the ratio of intermediate product 1, intermediate product 2, and N,N-dimethylformamide is 18.6g:68.3g:200mL; The Cl atom in intermediate product 2 has a strong electronegativity, which makes the C in the C-Cl bond a C positive ion. The OH in intermediate product 1 - The negative ion acts as a nucleophile to attack the C positive ion in the intermediate 2, replacing the Cl atom and causing S N Nucleophilic substitution reaction; by controlling the molar ratio of intermediate 1 and intermediate 2 to be close to 1:2, and the intermediate 2 is slightly excessive, a modifier is prepared; the structure of the modifier is shown below:

[0016] The prepared modifier molecules contain organic boron, organic nitrogen, pentaerythritol skeleton, triazine structure and benzene ring. Organic boron is a condensed phase flame retardant. When burned, it will generate boric anhydride or boric acid. When thermally cracked, it will form a glassy molten covering, which will promote the direct oxidation of the material into CO 2 , reducing the generation of CO, can improve the flame retardancy of the matrix; in addition, the introduced organic nitrogen belongs to the nitrogen flame retardant, which decomposes when heated, and the decomposition will consume a lot of heat in the combustion system, so that the temperature of the surface of the polymer matrix drops below the ignition temperature of the matrix, which can play a synergistic role with organic boron and greatly enhance the flame retardancy of the matrix; in addition, the pentaerythritol skeleton can improve the stability of the modifier molecule; the introduced triazine structure is connected with three o-hydroxyphenyl groups, which belongs to the triazine ultraviolet absorber. After absorbing ultraviolet rays of a specific wavelength, the hydrogen of the hydrogen bond in the molecule and the carbonyl oxygen or the nitrogen atom on the triazine ring form a chelate ring. When the stabilizer absorbs ultraviolet light energy, thermal vibration occurs, the hydrogen bond breaks, the chelate ring opens, and the absorbed ultraviolet energy is converted into harmless heat or other energy forms and released, which can greatly enhance the anti-ultraviolet performance of the matrix; finally, the molecule introduces 4 benzene rings, which can not only enhance the compatibility with the matrix, but also improve the impact resistance of the matrix.

[0017] Beneficial effects of the present invention: 1. The film material prepared by the present invention uses polycarbonate as a matrix, which gives the film material excellent impact resistance and transparency; 2. The added antioxidant can play a synergistic role and enhance the antioxidant properties of the membrane material; 3. The modifier is obtained through a series of reactions. The modifier molecule contains functional groups, which can improve the flame retardancy, UV resistance and impact resistance of the film material and has good stability; Therefore, the film material prepared by the present invention has good mechanical properties, high transparency, excellent impact resistance, flame retardancy and UV resistance, and has important application value in the field of film material technology. DETAILED DESCRIPTION

[0018] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0019] Example 1: Preparation of modifier: A1. Add 13.6 g of pentaerythritol and 12.4 g of boric acid into a three-necked flask equipped with a thermometer and an oil-water separator, place the device on an electric stirrer, add 100 mL of toluene as a water-carrying agent, heat to 115° C., stir and reflux until water is no longer generated, keep the temperature constant, continue the reaction for 3 h, and after the reaction is completed, remove toluene by distillation under reduced pressure to obtain an intermediate product 1; A2, 19.1g cyanuric chloride, 21.8g resorcinol and 150mL toluene were added to a three-necked flask equipped with a thermometer and a stirring device, mixed and stirred continuously, and then 7.4g aluminum chloride was added, and the reaction temperature was controlled to 65°C, and stirring was continued during the reaction. After the reaction was completed after 6h, the reaction was filtered, and toluene was removed by steam distillation, and then filtered, washed twice with anhydrous ethanol, and dried in an oven to obtain intermediate 2; A3. Add 18.6 g of intermediate product 1, 68.3 g of intermediate product 2 and 200 mL of N,N-dimethylformamide into a three-necked flask equipped with a thermometer and a stirring device; control the reaction temperature to 70°C, stir continuously during the reaction, and adjust the pH to neutral with sodium carbonate solution. Keep the reaction warm for 8 hours. After the reaction is completed, filter and dry to obtain a modifier.

[0020] Example 2: Preparation of modifier: A1. Add 27.2 g of pentaerythritol and 24.8 g of boric acid into a three-necked flask equipped with a thermometer and an oil-water separator, place the device on an electric stirrer, add 200 mL of toluene as a water-carrying agent, heat to 115° C., stir and reflux until water is no longer generated, keep the temperature constant, continue the reaction for 3 h, and after the reaction is completed, remove toluene by distillation under reduced pressure to obtain an intermediate product 1; A2, 38.2g of cyanuric chloride, 43.6g of resorcinol and 300mL of toluene were added to a three-necked flask equipped with a thermometer and a stirring device, mixed and stirred continuously, and then 14.8g of aluminum chloride was added, and the reaction temperature was controlled to 65°C, and stirring was continued during the reaction. After the reaction was completed after 6h, the reaction was filtered, and toluene was removed by steam distillation, and then filtered, washed twice with anhydrous ethanol, and dried in an oven to obtain intermediate product 2; A3. Add 37.2 g of intermediate product 1, 136.6 g of intermediate product 2 and 400 mL of N,N-dimethylformamide into a three-necked flask equipped with a thermometer and a stirring device; control the reaction temperature to 70°C, stir continuously during the reaction, and adjust the pH to neutral with sodium carbonate solution. Keep the reaction warm for 8 hours. After the reaction is completed, filter and dry to obtain a modifier.

[0021] Example 3: 80g of aromatic polycarbonate resin, 4g of antioxidant (prepared by compounding 3g of antioxidant 1010 and 1g of antioxidant 168), 5g of the modifier prepared in Example 1 and 3g of polytetrafluoroethylene anti-drip agent are dried; the dried polycarbonate resin is stirred in a high-speed mixer at a speed of 300rpm for 1min, and then the antioxidant, modifier, polytetrafluoroethylene anti-drip agent and 1g of paraffin are added, and stirring is continued for 4min. The obtained mixture is fed into a twin-screw extruder at a speed of 200 rpm, melt-extruded, granulated, and the obtained masterbatch is blow-molded by a molding machine to obtain a highly transparent impact-resistant film material.

[0022] Example 4: 85g of aromatic polycarbonate resin, 8g of antioxidant (6g of antioxidant 1010 and 2g of antioxidant 168), 10g of the modifier prepared in Example 2 and 4g of polytetrafluoroethylene anti-drip agent are dried; the dried polycarbonate resin is stirred in a high-speed mixer at a speed of 400rpm for 3min, and then the antioxidant, modifier, polytetrafluoroethylene anti-drip agent and 4g of calcium stearate are added, and stirring is continued for 8min. The obtained mixture is fed into a twin-screw extruder at a speed of 300 rpm, melt-extruded, granulated, and the obtained masterbatch is blow-molded by a molding machine to obtain a highly transparent impact-resistant film material.

[0023] Example 5: 90g of aromatic polycarbonate resin, 8g of antioxidant (6g of antioxidant 1010 and 2g of antioxidant 168), 15g of the modifier prepared in Example 2 and 5g of polytetrafluoroethylene anti-drip agent are dried; the dried polycarbonate resin is stirred in a high-speed mixer at a speed of 400rpm for 3min, and then the antioxidant, modifier, polytetrafluoroethylene anti-drip agent and 4g of stearic acid are added, and stirring is continued for 8min. The obtained mixture is fed into a twin-screw extruder at a speed of 300 rpm, melt-extruded, granulated, and the obtained masterbatch is blow-molded by a molding machine to obtain a highly transparent impact-resistant film material.

[0024] Comparative Example 1: A commercially available nitrogen-based flame retardant of equal mass was used to replace the modifier in Example 5, and the remaining steps were the same as those in Example 5.

[0025] Comparative Example 2: Using commercially available polycarbonate masterbatch.

[0026] Embodiments 3, 4, 5, and comparative examples 1 and 2 were made into corresponding shapes according to different test standards, and the following performance tests were performed: The notched impact strength is tested according to the national standard GB / T 1043.1-2008 "Determination of impact properties of simply supported beams of plastics"; The sample was placed in a xenon lamp aging test chamber for accelerated aging for 7 days. The aging conditions were air atmosphere, a xenon lamp wavelength of 500nm, and an irradiation intensity of 550W / m 2 , test the notched impact strength after aging; and calculate the retention rate of notched impact strength = notched impact strength after test / notched impact strength before test × 100%; The oxygen index is determined using the national standard GB / T 2406.2-2009 "Determination of Combustion Behavior of Plastics Using Oxygen Index Method"; The transmittance of Examples 3-5 in the range of 200-800 nm was measured using a UV-Vis spectrophotometer; The measured results are shown in the following table:

[0027] It can be seen from the above table that the film material prepared in the embodiment of the present invention has high transparency, and its impact resistance, flame retardancy and UV resistance are higher than those of the comparative example, and has important application value in the field of film material technology.

[0028] In the description of the specification, the description with reference to the terms "one embodiment", "example", "specific example", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0029] The above contents are merely examples and explanations of the present invention. Those skilled in the art may make various modifications or additions to the specific embodiments described or replace them in a similar manner. As long as they do not deviate from the invention or exceed the scope defined by the claims, they shall all fall within the protection scope of the present invention.

Claims

1. A method for preparing a highly transparent impact-resistant film material, characterized in that: The following steps are involved: The polycarbonate resin, the antioxidant, the modifier and the anti-dripping agent are dried; the dried polycarbonate resin is stirred in a high-speed mixer, and then the antioxidant, the modifier, the anti-dripping agent and the processing aid are added, and after continuing to stir, the dried polycarbonate resin is sent to a twin-screw extruder for melt extrusion and granulation, and the obtained masterbatch is blow-molded by a molding machine to obtain a highly transparent impact-resistant film material; Wherein, the modifier is prepared by the following steps: A1. Add pentaerythritol and boric acid into a three-necked flask, place it on an electric stirrer, add toluene, heat it to 115°C, stir and reflux until water is no longer generated, keep the temperature constant, and continue the reaction for 3 hours. After the reaction is completed, remove toluene by distillation under reduced pressure to obtain intermediate product 1; A2, add cyanuric chloride, resorcinol and toluene into a three-necked flask, mix and stir continuously, then add aluminum chloride, the reaction temperature is 65°C, and stir continuously, react for 6 hours, the reaction is complete, filter, steam distill, filter again, wash, and dry in an oven to obtain intermediate product 2; A3. Add intermediate product 1, intermediate product 2 and N,N-dimethylformamide into a three-necked flask; the reaction temperature is 70°C, stirring is continued during the reaction, and the pH is adjusted to neutral. The reaction is kept warm for 8 hours. After the reaction is completed, the product is filtered and dried to obtain a modifier.

2. The method for preparing a highly transparent impact-resistant film material according to claim 1, characterized in that: The ratio of pentaerythritol, boric acid and toluene used in step A1 is 13.6 g:12.4 g:100 mL.

3. The method for preparing a highly transparent impact-resistant film material according to claim 1, characterized in that: In step A2, the ratio of cyanuric chloride, resorcinol, toluene and aluminum chloride is 19.1 g:21.8 g:150 mL:7.4 g.

4. The method for preparing a highly transparent impact-resistant film material according to claim 1, characterized in that: In step A3, the ratio of the amount of intermediate product 1, intermediate product 2, and N,N-dimethylformamide used is 18.6 g:68.3 g:200 mL.

5. The method for preparing a highly transparent impact-resistant film material according to claim 1, characterized in that: The raw materials are calculated in parts by weight as follows: 80-90 parts of polycarbonate resin, 4-8 parts of antioxidant, 5-15 parts of modifier, 3-5 parts of anti-drip agent, and 1-4 parts of processing aid.

6. The method for preparing a highly transparent impact-resistant film material according to claim 1, characterized in that: The antioxidant is prepared by compounding a hindered phenol antioxidant and a phosphite antioxidant in a mass ratio of 3:

1.

7. The method for preparing a highly transparent impact-resistant film material according to claim 1, characterized in that: The anti-drip agent is one of a polytetrafluoroethylene anti-drip agent and a silicone anti-drip agent.

8. The method for preparing a highly transparent impact-resistant film material according to claim 1, characterized in that: The processing aid is one or more of paraffin, stearic acid, calcium stearate and zinc stearate.

9. A highly transparent impact-resistant film material, characterized in that: Prepared according to the method according to any one of claims 1 to 8.

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