A waterproof protective film and its preparation method and application

Abstract

The invention discloses a waterproof protective film, which belongs to the technical field of protective films. The waterproof protective film comprises the following raw materials in parts by weight: 80-100 parts of PET resin, 10-15 parts of fluorine-containing silicone oil, 24-40 parts of talc-based barrier fillers, and 1-3 parts of an antioxidant. The preparation method is as follows: the raw materials are added into a high-speed mixer and mixed, extruded, and subjected to T-type die casting to form a film, cast, and longitudinally hot stretched. The present invention uses PET resin as a main material, and by adding fluorine-containing silicone oil and talc-based barrier fillers, the protective film is given excellent waterproof performance, corrosion resistance, and flame retardant performance. The fluorine-containing silicone oil and talc-based barrier filler are introduced into the PET resin base material, extruded and cast, and does not require coating treatment. The preparation method is simple, and when applied to the surface of product transportation, the transported products can be prevented from being polluted and corroded by rainwater. The film has excellent flame retardant effect, providing safety guarantee for product transportation.

Description

Technical Field

[0001] The present invention belongs to the technical field of protective films, and in particular relates to a waterproof protective film and a preparation method and application thereof. Background Art

[0002] PET film has excellent mechanical properties, gas barrier properties, heat resistance, weather resistance, and electrical insulation properties, and is widely used in many fields, including photosensitive materials, packaging materials, agricultural film materials, electrical insulation materials, and magnetic recording materials. However, its insufficient surface hydrophobicity limits its application as a waterproof protective film in certain fields, such as solar panel surfaces and architectural glass surfaces. To compensate for this deficiency and expand the application range of PET film, the PET film is generally subjected to hydrophobic enhancement. For example, Chinese patent CN113185742A discloses a waterproof and corrosion-resistant protective film and a preparation method thereof, comprising a PET base film, a first film layer, and a second film layer; the first film layer is a composite of modified polyimide and nano-ZnO; and the second film layer is a hydrotalcite-like super-hydrophobic layer. Although this patent improves the hydrophobic, waterproof, and corrosion-resistant properties of the PET film by laminating the first and second film layers on the PET base film, the processing process is complex, requiring two lamination processes, and there are problems such as a lack of covalent bonding between the first and second film layers and the PET film, and unstable lamination results. Summary of the Invention

[0003] The purpose of the present invention is to provide a waterproof protective film, which uses PET resin as the main material and is endowed with excellent waterproof performance, corrosion resistance and flame retardant properties by adding fluorine-containing silicon and talc barrier fillers.

[0004] Another object of the present invention is to provide a method for preparing a waterproof protective film, which is obtained by introducing fluorine-containing silicon and talc powder barrier fillers into a PET resin base material and extruding and casting. No coating treatment is required, and the preparation method is simple.

[0005] The purpose of the present invention can be achieved through the following technical solutions:

[0006] A waterproof protective film comprises the following raw materials in parts by weight: 80-100 parts of PET resin, 10-15 parts of fluorine-containing silicone oil, 24-40 parts of talc-based barrier filler, and 1-3 parts of antioxidant;

[0007] The method for preparing the waterproof protective film comprises the following steps:

[0008] The required raw materials are weighed according to the formula ratio, added to a high-speed mixer and mixed for 10-15 minutes, and then transferred to a twin-screw extruder at a speed of 145-150r / min and a temperature of 250-260°C. The film is cast through a T-head die, and then cast on a casting roller with a roller temperature of 25°C. The film is longitudinally hot stretched with a stretching ratio of 4 times and a stretching rate of 400mm / min to obtain the waterproof protective film.

[0009] As a further embodiment of the present invention, the fluorine-containing silicone oil is prepared by the following steps:

[0010] Add amino silicone oil and tetrahydrofuran to the reactor, raise the temperature to 60°C in a nitrogen atmosphere, add hexafluorobutyl acrylate, react at 60°C for 5 hours, then add vinyltriethoxysilane and continue to react for 5 hours. After the reaction is completed, remove tetrahydrofuran by rotary evaporation to obtain fluorine-containing silicone oil.

[0011] As a further embodiment of the present invention, the amount ratio of amino silicone oil, tetrahydrofuran, hexafluorobutyl acrylate and vinyl triethoxysilane is 8.95g:40-50mL:0.45-0.62g:0.28-0.35g, and the amino silicone oil is an amino-terminated polysiloxane, which can be purchased from Shanghai Huiyan New Materials Co., Ltd. HY-2300 (viscosity 60-150cp, 25°C), Dow Chemical's OFX-8040A (viscosity 800-5000cp, 25°C) and OFX-8209A (viscosity 300-1200cp, 25°C).

[0012] Amino silicone oil is an organic silicon polymer with a main chain of silicon-oxygen main chain and amino side chain, which has the characteristics of high and low temperature resistance and hydrophobicity. The present invention uses this as a base material, and through the addition reaction between amino groups and unsaturated double bonds, hexafluorobutyl and silane structures are chemically grafted on the amino silicone oil molecular chain to obtain fluorine-containing silicone oil. The fluorine-containing silicone oil is added to the protective film. On the one hand, long silicon-oxygen silicon chains and fluorocarbon long chains are introduced to improve the hydrophobicity of the protective film. On the other hand, the siloxane structure is introduced. First, it reacts with the hydroxyl or carboxyl groups in the PET resin to overcome the problem of easy hydrolysis of the PET resin. Second, it reacts with the active groups on the surface of the talc barrier filler to further improve the interface bonding strength between the talc barrier filler and the PET resin, so that the talc barrier filler can effectively play a barrier, reinforcement and flame retardant role. Third, the high flame retardant element content (silicon) itself is utilized to further improve the flame retardant properties of the protective film.

[0013] As a further embodiment of the present invention, the talc-based barrier filler is prepared by the following steps:

[0014] The talc powder was placed in a muffle furnace and treated at a constant temperature of 340-360°C for 2-3 hours, then taken out and cooled to room temperature to obtain pretreated talc powder. The treated talc powder was added to a phosphoric acid solution, stirred and transferred to a ball mill, and ball milled at 150-250r / min for 30 minutes. The mixture was then transferred to a reactor, the temperature was controlled at 70°C, urea was added, and the temperature was raised to 125°C. The reaction was kept warm for 40 minutes. The reaction product was then transferred to a tray, treated at 240°C for 2 hours, cooled to room temperature, and crushed to an average particle size of 0.5-2 microns to obtain a talc-based barrier filler.

[0015] As a further embodiment of the present invention, the mass ratio of talc powder, phosphoric acid and urea is 1:1:1.5, and the mass fraction of the phosphoric acid solution is 50-70%.

[0016] Under the action of mechanical stirring, the talc powder layers slide, exposing active hydroxyl groups, which are then reacted with phosphoric acid. A large number of active groups are introduced between the talc powder layers and on the surface to react with urea for polymerization. Ammonium polyphosphate structures are introduced between the talc layers and on the surface to reduce the hydrophilicity of the talc powder and improve its compatibility with the protective film base material. The obtained talc-based barrier filler is introduced into the protective film, where it can be evenly distributed in the protective film to form a strong support network with excellent mechanical properties, thereby improving the mechanical properties of the protective film. It also has a significant barrier effect, prolonging or hindering the invasion of corrosion structures and improving the corrosion resistance of the protective film. More importantly, when the protective film is burned by fire, the talc-based barrier filler is heated to produce difficult-to-decompose substances that cover the surface of the high molecular polymer, cutting off the combustion heat, exerting the flame retardant effect of the nitrogen-phosphorus flame retardant, and improving the flame retardant properties of the protective film.

[0017] As a further embodiment of the present invention, the intrinsic viscosity of the PET resin is 0.78-1.1 dl / g.

[0018] As a further embodiment of the present invention, the antioxidant is one or two of antioxidant 1010, antioxidant 168 and antioxidant 1076.

[0019] As a further solution of the present invention, a waterproof protective film is used for surface protection during product transportation.

[0020] Beneficial effects of the present invention:

[0021] The present invention provides a waterproof protective film, which uses PET resin as a main material and is endowed with excellent waterproof performance, corrosion resistance and flame retardant performance by adding fluorine-containing silicon and talc barrier fillers. The film is obtained by introducing fluorine-containing silicon and talc barrier fillers into the PET resin base material and extruding and casting, and does not require coating treatment. The preparation method is simple and can be applied to the surface of product transportation to prevent the transported products from being contaminated and corroded by rainwater. The film also has excellent flame retardant effect, providing safety guarantee for product transportation. DETAILED DESCRIPTION

[0022] 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 embodiments described 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 making any creative efforts shall fall within the scope of protection of the present invention.

[0023] Example 1

[0024] A fluorine-containing silicone oil is prepared by the following steps:

[0025] 8.95 g of amino silicone oil and 40 mL of tetrahydrofuran were added to the reactor, the temperature was raised to 60 ° C in a nitrogen atmosphere, 0.45 g of hexafluorobutyl acrylate was added, and the reaction was carried out at 60 ° C for 5 h. Then 0.28 g of vinyltriethoxysilane was added and the reaction was continued for 5 h. After the reaction, the tetrahydrofuran was removed by rotary evaporation to obtain fluorine-containing silicone oil. The amino silicone oil is an amino-terminated polysiloxane purchased from Shanghai Huiyan New Materials Co., Ltd. HY-2300 (viscosity 60-150 cp, 25 ° C).

[0026] Example 2

[0027] A fluorine-containing silicone oil is prepared by the following steps:

[0028] 8.95 g of amino silicone oil and 50 mL of tetrahydrofuran were added to the reactor, the temperature was raised to 60 ° C in a nitrogen atmosphere, 0.62 g of hexafluorobutyl acrylate was added, and the reaction was carried out at 60 ° C for 5 h. Then 0.35 g of vinyltriethoxysilane was added and the reaction was continued for 5 h. After the reaction was completed, the tetrahydrofuran was removed by rotary evaporation to obtain fluorine-containing silicone oil. The amino silicone oil is an amino-terminated polysiloxane purchased from Dow Chemical as OFX-8209A (viscosity 300-1200 cp, 25 ° C).

[0029] Comparative Example 1

[0030] This comparative example is the amino silicone oil in Example 1.

[0031] Example 3

[0032] A talc-based barrier filler is prepared by the following steps:

[0033] The talc powder was placed in a muffle furnace at a constant temperature of 340°C for 3 hours, taken out and cooled to room temperature to obtain pretreated talc powder. 10g of the treated talc powder was added to a phosphoric acid solution consisting of 10g of phosphoric acid and 15g of deionized water, and the mixture was transferred to a ball mill after stirring. The mixture was ball-milled at 150r / min for 30 minutes, and then transferred to a reactor. The temperature was controlled at 70°C, 15g of urea was added, and the temperature was raised to 125°C. The mixture was kept warm for 40 minutes. The reaction product was then transferred to a tray, treated at 240°C for 2 hours, cooled to room temperature, and crushed to an average particle size of 0.5-2 microns to obtain a talc-based barrier filler.

[0034] Example 4

[0035] A talc-based barrier filler is prepared by the following steps:

[0036] The talc powder was placed in a muffle furnace and treated at a constant temperature of 360°C for 2 hours, then taken out and cooled to room temperature to obtain pretreated talc powder. 10g of the treated talc powder was added to a phosphoric acid solution consisting of 10g of phosphoric acid and 20g of deionized water, and the mixture was transferred to a ball mill after stirring. The mixture was ball-milled at 250r / min for 30 minutes, and then transferred to a reactor. The temperature was controlled at 70°C, 15g of urea was added, and the temperature was raised to 125°C. The mixture was kept warm for 40 minutes. The reaction product was then transferred to a tray, treated at 240°C for 2 hours, cooled to room temperature, and crushed to an average particle size of 0.5-2 microns to obtain a talc-based barrier filler.

[0037] Comparative Example 2

[0038] This comparative example is talc powder with an average particle size of 0.5-2 microns.

[0039] Example 5

[0040] A waterproof protective film comprises the following raw materials in parts by weight: 80 parts of PET resin, 10 parts of the fluorine-containing silicone oil of Example 1, 24 parts of the talc-based barrier filler of Example 3, and 1 part of an antioxidant;

[0041] The method for preparing the waterproof protective film comprises the following steps:

[0042] The required raw materials were weighed according to the formula ratio, added to a high-speed mixer and mixed for 10 minutes, and then transferred to a twin-screw extruder at a speed of 145 r / min and a temperature of 250°C. The film was cast through a T-head die, and then cast on a casting roller at a roller temperature of 25°C. The film was longitudinally hot stretched with a stretching ratio of 4 times and a stretching rate of 400 mm / min to obtain the waterproof protective film.

[0043] The intrinsic viscosity of the PET resin is 0.78 dl / g, and the antioxidant is antioxidant 1010.

[0044] Example 6

[0045] A waterproof protective film comprises the following raw materials in parts by weight: 90 parts of PET resin, 12 parts of the fluorine-containing silicone oil of Example 2, 34 parts of the talc-based barrier filler of Example 4, and 2 parts of an antioxidant;

[0046] The method for preparing the waterproof protective film comprises the following steps:

[0047] The required raw materials were weighed according to the formula ratio, added to a high-speed mixer and mixed for 15 minutes, and then transferred to a twin-screw extruder at a speed of 150 r / min and a temperature of 255°C. The film was cast through a T-head die, and then cast on a casting roller at a roller temperature of 25°C. The film was longitudinally hot stretched with a stretching ratio of 4 times and a stretching rate of 400 mm / min to obtain the waterproof protective film.

[0048] The intrinsic viscosity of the PET resin is 0.78 dl / g, and the antioxidant is antioxidant 1010.

[0049] Example 7

[0050] A waterproof protective film comprises the following raw materials in parts by weight: 100 parts of PET resin, 15 parts of the fluorine-containing silicone oil of Example 1, 40 parts of the talc-based barrier filler of Example 4, and 3 parts of an antioxidant;

[0051] The method for preparing the waterproof protective film comprises the following steps:

[0052] The required raw materials were weighed according to the formula ratio, added to a high-speed mixer and mixed for 15 minutes, and then transferred to a twin-screw extruder at a speed of 150 r / min and a temperature of 260°C. The film was cast through a T-head die, and then cast on a casting roller at a roller temperature of 25°C. The film was longitudinally hot stretched with a stretching ratio of 4 times and a stretching rate of 400 mm / min to obtain the waterproof protective film.

[0053] The intrinsic viscosity of the PET resin is 1.1 dl / g, and the antioxidant is antioxidant 168.

[0054] Comparative Example 3

[0055] The fluorine-containing silicone oil in Example 5 was replaced by the substance in Comparative Example 1, and the remaining raw materials and preparation process were the same as in Example 5.

[0056] Comparative Example 4

[0057] The talc-based barrier filler in Example 5 was replaced with the material in Comparative Example 2, and the remaining raw materials and preparation process were the same as in Example 5.

[0058] The performance tests of the waterproof protective films obtained in Examples 5 to 7 and Comparative Examples 3 and 4 were conducted, and the test contents were as follows:

[0059] (1) Tensile strength: With reference to GB / T1040.2-2006, the protective film samples were subjected to tensile tests using an Instron-365 electronic universal material testing machine from Meters Industrial Systems Co., Ltd. The effective size of the test sample was 3 cm × 3 cm × 1 μm, the clamp spacing was 20 mm, the tensile rate was 5 mm / min, and the ambient temperature was 25°C.

[0060] (2) Contact angle test: The hydrophobicity of the prepared protective film samples was tested using a contact angle meter. Specifically, a 0.5 mm needle was used to drop a 5 μL water droplet. Each protective film sample was tested 5 times and the average value was calculated.

[0061] (III) Corrosion Resistance: 304 stainless steel (size 40 mm × 20 mm × 0.4 mm) was tightly coated with the protective film samples prepared in the Examples and Comparative Examples to prepare test specimens. A pitting corrosion test was conducted according to the method of GB / T17897-1999. 100 g of analytically pure ferric chloride (FeCl3·6H20) was dissolved in 900 mL of 0.05 mol / L hydrochloric acid solution to prepare a ferric chloride solution. The solution was poured into a beaker, placed in a constant temperature water bath and heated to 35°C. After reaching the specified temperature, the sample was placed in the beaker and continuously immersed for 24 h. The corrosion rate was calculated by weight loss method.

[0062] Corrosion rate = (Wbefore - Wafter) / (S t), Wbefore is the weight of the sample before the test, Wafter is the weight of the sample after the test, S is the total area of ​​the sample, and t is the test time;

[0063] (IV) Flame retardant properties: Standard specimens were prepared according to GB / T2406-93 test, and the limiting oxygen index (LOI) test was performed using the OJN-9307 digital oxygen index tester produced by Shenzhen Oujienuo Technology Co., Ltd. The specimen size was 120 mm × 6.5 mm × 3 mm;

[0064] The test results are shown in Table 1:

[0065] Table 1

[0066] project Example 5 Example 6 Example 7 Comparative Example 3 Comparative Example 4 Tensile strength (MPa) 47.9 49.8 50.4 47.8 41.3 Contact angle (°) 127.8 128.3 130.4 120.5 122.5 <![CDATA[Corrosion rate [g / (m 2 ·h)]]]> 0.15 0.11 0.09 0.18 0.20 LOI (%) 28.5 29.6 30.2 28.3 24.6

[0067] It can be seen from Table 1 that, compared with Comparative Example 3 and Comparative Example 4, the waterproof protective films obtained in Example 5, Example 6 and Example 7 not only have good mechanical strength and waterproof performance, but also have excellent corrosion resistance and flame retardancy.

[0068] It should be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that includes a list of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus.

[0069] While 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 these embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the appended claims and their equivalents.

Claims

1. A waterproof protective film, characterized in that: The invention comprises the following raw materials in parts by weight: 80-100 parts of PET resin, 10-15 parts of fluorine-containing silicone oil, 24-40 parts of talc-based barrier filler, and 1-3 parts of antioxidant; Fluorinated silicone oil is made by the following steps: Add amino silicone oil and tetrahydrofuran to the reactor, raise the temperature to 60°C in a nitrogen atmosphere, add hexafluorobutyl acrylate, react at 60°C for 5 hours, then add vinyltriethoxysilane and continue to react for 5 hours to obtain fluorine-containing silicone oil; Talc-based barrier fillers are made by the following steps: The talc powder was placed in a muffle furnace at a constant temperature of 340-360°C for 2-3 hours, taken out and cooled to room temperature to obtain pretreated talc powder, and the treated talc powder was added to a phosphoric acid solution, stirred and transferred to a ball mill, and after ball milling for 30 minutes, transferred to a reactor, the temperature was controlled at 70°C, urea was added, and then the temperature was raised to 125°C. The reaction was kept warm for 40 minutes, and then the reaction product was transferred to a tray, treated at 240°C for 2 hours, cooled to room temperature, and crushed to an average particle size of 0.5-2 microns to obtain a talc-based barrier filler.

2. A waterproof protective film according to claim 1, characterized in that: The usage ratio of amino silicone oil, tetrahydrofuran, hexafluorobutyl acrylate and vinyltriethoxysilane is 8.95g:40-50mL:0.45-0.62g:0.28-0.35g.

3. The waterproof protective film according to claim 1, characterized in that: The mass ratio of talc powder, phosphoric acid and urea is 1:1:1.5, and the mass fraction of the phosphoric acid solution is 50-70%.

4. The waterproof protective film according to claim 1, characterized in that: The intrinsic viscosity of PET resin is 0.78-1.1 dl / g.

5. The method for preparing a waterproof protective film according to claim 1, characterized in that: The following steps are involved: The required raw materials are weighed according to the formula ratio, added to a high-speed mixer and mixed for 10-15 minutes, and then transferred to a twin-screw extruder at a speed of 145-150r / min and a temperature of 250-260°C. The film is cast through a T-head die, and then cast on a casting roller with a roller temperature of 25°C. The film is longitudinally hot stretched with a stretching ratio of 4 times and a stretching rate of 400mm / min to obtain the waterproof protective film.

6. An application of the waterproof protective film according to claim 1, characterized in that: Used for surface protection during product transportation.