A yellowing-resistant oxidized PVC film and its preparation method

Abstract

The present invention discloses a yellowing-resistant oxidized PVC film and a preparation method thereof, relating to the field of PVC films, and comprising the following raw materials in parts by weight: 60-90 parts of PVC; 20-60 parts of a plasticizer; 2-8 parts of calcium stearate; 10-30 parts of modified talcum powder; 1-3 parts of an antioxidant; 5-15 parts of almond shell powder; the modified talcum powder is prepared by modifying the following raw materials: talcum powder, ethanol, 3-mercaptopropyltrimethoxysilane, copper chloride, and polypropylene. This application has the effect of improving the yellowing resistance of the PVC film.

Description

Technical Field

[0001] The present invention relates to the field of PVC films, and particularly to a yellowing-resistant and oxidation-resistant PVC film and a preparation method thereof. Background Art

[0002] PVC (polyvinyl chloride) is a widely used plastic material and has a wide range of applications in various industries due to its low cost, durability, easy processing and other characteristics.

[0003] However, PVC films are prone to yellowing and oxidation under the influence of light and heat during use, which seriously affects the appearance and quality of products. To solve this problem, many attempts have been made by those skilled in the art, but the prior art still fails to completely solve the yellowing problem of PVC. Summary of the Invention

[0004] In order to improve the yellowing resistance of PVC films, the present application provides a yellowing-resistant and oxidation-resistant PVC film and a preparation method thereof.

[0005] In a first aspect, a yellowing-resistant and oxidation-resistant PVC film provided by the present application adopts the following technical solution:

[0006] A yellowing-resistant and oxidation-resistant PVC film, comprising the following raw materials in parts by weight: 60 - 90 parts of PVC; 20 - 60 parts of plasticizer; 2 - 8 parts of calcium stearate; 10 - 30 parts of modified talcum powder; 1 - 3 parts of antioxidant; 5 - 15 parts of almond shell powder; the modified talcum powder is prepared by modifying the following raw materials: talcum powder, ethanol, 3-mercaptopropyltrimethoxysilane, copper chloride and polypropylene.

[0007] By adopting the above technical solution, PVC is the main component of the film, and the modified talcum powder has better dispersibility and compatibility, thereby reducing yellowing caused by filler aggregation. Almond shell powder, as a natural filler, has a certain antioxidant effect due to the phenolic substances it contains, which helps to improve the yellowing resistance of the PVC film. The combined action of each component can improve the yellowing resistance of the PVC film. Through reasonable formula design and processing technology, it is possible to slow down the yellowing process while maintaining the excellent physical properties of the PVC film.

[0008] Preferably, the preparation method of the modified talcum powder is: mixing and stirring 10 - 20 parts by weight of talcum powder and 50 - 150 parts by weight of ethanol, adding 5 - 15 parts by weight of 3-mercaptopropyltrimethoxysilane, 1 - 5 parts by weight of copper chloride and 5 - 10 parts by weight of polypropylene after ultrasonic treatment, mixing and stirring, filtering by suction, washing and then drying to obtain the modified talcum powder.

[0009] By adopting the above technical solution, the talcum powder in the present application is modified. The 3-mercaptopropyltrimethoxysilane has hydrophilic groups and hydrophobic groups on its surface, which react with the surface of the talcum powder to coat the surface of the talcum powder with an organic coupling agent. Copper chloride chelates with the mercapto and hydroxyl functional groups of 3-mercaptopropyltrimethoxysilane to form a stable complex, thereby improving the stability and yellowing resistance of the PVC film.

[0010] Preferably, the weight ratio of the talcum powder, 3-mercaptopropyltrimethoxysilane, copper chloride and polypropylene is (1.6 - 1.8):1:(0.15 - 0.23):(0.6 - 0.7).

[0011] By adopting the above technical solution, the talcum powder, 3-mercaptopropyltrimethoxysilane, copper chloride and polypropylene cooperate together. The 3-mercaptopropyltrimethoxysilane can be grafted onto the PVC to improve the compatibility between the PVC and the polypropylene, thereby further improving the tensile strength of the PVC film.

[0012] Preferably, the almond shell powder is modified almond shell powder, and the preparation method of the modified almond shell powder is as follows: Mix 3 - 9 parts by weight of sodium alginate with 10 - 30 parts by weight of water, then add 10 - 20 parts by weight of almond shell powder and 5 - 10 parts by weight of polyethylene glycol, disperse ultrasonically, filter, dry and then grind to obtain the modified almond shell powder.

[0013] By adopting the above technical solution, sodium alginate is used as a stabilizer to reduce the thermal degradation of the PVC during processing and use. The almond shell powder contains phenolic substances and has a certain antioxidant effect, which helps to delay the yellowing of the PVC. The almond shell powder and sodium alginate are blended and then mixed through polyethylene glycol to improve the mechanical strength of the almond shell powder, thereby improving the mechanical strength of the almond shell powder as a filler filled in the PVC.

[0014] Preferably, the weight ratio of the almond shell powder, polyethylene glycol and sodium alginate is (2.4 - 3.2):(1.2 - 1.4):1.

[0015] By adopting the above technical solution, when the almond shell powder, polyethylene glycol and sodium alginate are in a specific weight ratio, there are a large number of hydroxyl and carboxyl groups in the molecular weight of ammonium alginate, which form a hydrogel with polyethylene glycol and cover the almond shell powder. The almond shell powder is evenly dispersed in the PVC, which helps to reduce the yellowing phenomenon caused by heat or light in the PVC, and at the same time makes the PVC have excellent tensile strength.

[0016] Preferably, the degree of polymerization of the PVC is 1000 - 1100.

[0017] By adopting the above technical solution, selecting a suitable degree of polymerization can effectively improve the tensile strength and yellowing resistance of the PVC.

[0018] Preferably, the weight ratio of the modified talcum powder, PVC, and modified almond shell powder is 1:(3.8 - 4.2):(0.55 - 0.65).

[0019] By adopting the above technical solution, the modified talcum powder has improved dispersibility and compatibility in PVC after surface treatment, further enhancing the tensile strength of PVC. The modified almond shell powder can further improve the thermal stability of PVC, thus helping to reduce the yellowing phenomenon caused by filler aggregation. The combined use of the modified talcum powder and the modified almond shell powder enhances the tensile strength while improving the yellowing resistance of PVC.

[0020] The plasticizer is one of dioctyl phthalate and diisooctyl phthalate.

[0021] Preferably, the antioxidant is one of antioxidant 168 and antioxidant 1010.

[0022] By adopting the above technical solution, selecting appropriate plasticizers and antioxidants can effectively improve the yellowing resistance of the PVC film.

[0023] In a second aspect, a method for preparing a yellowing-resistant PVC film provided by this application adopts the following technical solution:

[0024] A method for preparing a yellowing-resistant PVC film includes the following steps: mixing and stirring PVC, plasticizer, calcium stearate, modified talcum powder, antioxidant, and almond shell powder, continuing to stir after cooling, calendering, and drying to obtain the yellowing-resistant oxidized PVC film.

[0025] By adopting the above technical solution, the raw materials for preparing the PVC film are processed step by step, making the mixing of various raw materials more uniform, thus obtaining a yellowing-resistant PVC film.

[0026] In summary, this application has the following beneficial technical effects:

[0027] 1. PVC is the main component of the film. The modified talcum powder has better dispersibility and compatibility, thus reducing yellowing caused by filler aggregation. As a natural filler, almond shell powder has a certain antioxidant effect due to the phenolic substances it contains, helping to improve the yellowing resistance of the PVC film. The combined action of each component can improve the yellowing resistance of the PVC film. Through reasonable formulation design and processing technology, it is possible to slow down the yellowing process while maintaining the excellent physical properties of the PVC film.

[0028] 2. The talcum powder in this application is modified. 3-mercaptopropyltrimethoxysilane has hydrophilic and hydrophobic groups on its surface, which react with the surface of the talcum powder to coat the surface of the talcum powder with an organic coupling agent; copper chloride chelates with the mercapto and hydroxyl functional groups of 3-mercaptopropyltrimethoxysilane to form a stable complex, thereby improving the stability and yellowing resistance of the PVC film. Detailed implementation mode

[0029] The present application will be further described in detail below in conjunction with examples and comparative examples.

[0030] Example

[0031] Example 1

[0032] A method for preparing a yellowing-resistant oxidized PVC film includes the following steps: Put 60 g of PVC, 20 g of plasticizer, 2 g of calcium stearate, 10 g of modified talcum powder, 1 g of antioxidant and 5 g of almond shell powder into a stirrer and mix and stir at a temperature of 80 °C and a rotation speed of 800 r / min for 30 min. After cooling to 60 °C, continue to stir for 10 min. Then use a calender for calendering and dry at a temperature of 100 °C for 2 h to obtain the yellowing-resistant oxidized PVC film. The polymerization degree of PVC is 1000, the grade is SG-5, purchased from Sichuan Jinlu Resin Co., Ltd., the antioxidant is antioxidant 1010, and the plasticizer is dioctyl phthalate.

[0033] The preparation method of the modified talcum powder is as follows: Mix 10 g of talcum powder and 50 g of 95% ethanol and stir for 2 min. After ultrasonic treatment in an ultrasonic cleaner for 15 min, add 5 g of 3-mercaptopropyltrimethoxysilane, 1 g of copper chloride and 5 g of polypropylene and mix and stir for 10 min. Then filter by suction, wash with absolute ethanol and dry in an oven at a temperature of 55 °C for 2 h to obtain the modified talcum powder. The polypropylene is selected from Sabic, and the grade is 8511E.

[0034] Example 2

[0035] A method for preparing a yellowing-resistant oxidized PVC film includes the following steps: Put 90 g of PVC, 60 g of plasticizer, 8 g of calcium stearate, 30 g of modified talcum powder, 3 g of antioxidant and 15 g of almond shell powder into a stirrer and mix and stir at a temperature of 80 °C and a rotation speed of 800 r / min for 30 min. After cooling to 60 °C, continue to stir for 10 min. Then use a calender for calendering and dry at a temperature of 100 °C for 2 h to obtain the yellowing-resistant oxidized PVC film. The polymerization degree of PVC is 1000, the grade is SG-5, purchased from Sichuan Jinlu Resin Co., Ltd., the antioxidant is antioxidant 168, and the plasticizer is diisooctyl phthalate.

[0036] The preparation method of the modified talcum powder is as follows: Mix 10 g of talcum powder and 50 g of 95% ethanol and stir for 2 min. After ultrasonic treatment in an ultrasonic cleaner for 15 min, add 5 g of 3-mercaptopropyltrimethoxysilane, 1 g of copper chloride and 5 g of polypropylene, and stir for 10 min. Filter by suction, wash with absolute ethanol, and then dry in an oven at 55 °C for 2 h to obtain the modified talcum powder. The polypropylene is selected from Sabic, with the grade of 8511E.

[0037] Example 3

[0038] A preparation method of a yellowing-resistant and oxidation-resistant PVC film includes the following steps: Put 75 g of PVC, 40 g of plasticizer, 5 g of calcium stearate, 20 g of modified talcum powder, 2 g of antioxidant and 10 g of almond shell powder into a stirrer, and mix and stir at 80 °C and a rotation speed of 800 r / min for 30 min. After cooling to 60 °C, continue to stir for 10 min, roll with a calender, and dry at 100 °C for 2 h to obtain the yellowing-resistant and oxidation-resistant PVC film. The degree of polymerization of PVC is 1000, the grade is SG-5, purchased from Sichuan Jinlu Resin Co., Ltd., the antioxidant is antioxidant 1010, and the plasticizer is dioctyl phthalate.

[0039] The preparation method of the modified talcum powder is as follows: Mix 10 g of talcum powder and 50 g of 95% ethanol and stir for 2 min. After ultrasonic treatment in an ultrasonic cleaner for 15 min, add 5 g of 3-mercaptopropyltrimethoxysilane, 1 g of copper chloride and 5 g of polypropylene, and stir for 10 min. Filter by suction, wash with absolute ethanol, and then dry in an oven at 55 °C for 2 h to obtain the modified talcum powder. The polypropylene is selected from Sabic, with the grade of 8511E.

[0040] Example 4

[0041] A preparation method of a yellowing-resistant and oxidation-resistant PVC film, which is different from that of Example 3, is as follows: The preparation method of the modified talcum powder is: Mix 20 g of talcum powder and 150 g of 95% ethanol and stir for 2 min. After ultrasonic treatment in an ultrasonic cleaner for 15 min, add 15 g of 3-mercaptopropyltrimethoxysilane, 5 g of copper chloride and 10 g of polypropylene, and stir for 10 min. Filter by suction, wash with absolute ethanol, and then dry in an oven at 55 °C for 2 h to obtain the modified talcum powder. The polypropylene is selected from Sabic, with the grade of 8511E.

[0042] Example 5

[0043] A preparation method of a yellowing-resistant and oxidation-resistant PVC film, which is different from that of Example 3, is that in the process of preparing the modified talcum powder, the input amount of talcum powder is 16 g, the input amount of 3-mercaptopropyltrimethoxysilane is 10 g, the input amount of copper chloride is 1.5 g, and the input amount of polypropylene is 6 g.

[0044] Example 6

[0045] A preparation method of a yellowing-resistant oxidized PVC film, which is different from Example 3 in that during the preparation of modified talc powder, the input amount of talc powder is 18 g, the input amount of 3-mercaptopropyltrimethoxysilane is 10 g, the input amount of copper chloride is 2.3 g, and the input amount of polypropylene is 7 g.

[0046] Example 7

[0047] A preparation method of a yellowing-resistant oxidized PVC film, which is different from Example 6 in that almond shell powder is replaced with modified almond shell powder in equal amount, and the preparation method of the modified almond shell powder is as follows: Mix 3 g of sodium alginate with 10 g of water and stir for 2 min, then add 10 g of almond shell powder and 5 g of polyethylene glycol and stir for 10 min, then perform ultrasonic dispersion in an ultrasonic cleaner for 30 min, filter and transfer to an oven, and dry at a temperature of 70 °C for 2 h and then grind to obtain the modified almond shell powder. The polyethylene glycol is selected as Saudi PEG400 with the brand number CY-040.

[0048] Example 8

[0049] A preparation method of a yellowing-resistant oxidized PVC film, which is different from Example 6 in that almond shell powder is replaced with modified almond shell powder in equal amount, and the preparation method of the modified almond shell powder is as follows: Mix 9 g of sodium alginate with 30 g of water and stir for 2 min, then add 20 g of almond shell powder and 10 g of polyethylene glycol and stir for 10 min, then perform ultrasonic dispersion in an ultrasonic cleaner for 30 min, filter and transfer to an oven, and dry at a temperature of 70 °C for 2 h and then grind to obtain the modified almond shell powder. The polyethylene glycol is selected as Saudi PEG400 with the brand number CY-040.

[0050] Example 9

[0051] A preparation method of a yellowing-resistant oxidized PVC film, which is different from Example 8 in that during the preparation of modified almond shell powder, the input amount of almond shell powder is 12 g, the input amount of polyethylene glycol is 6 g, and the input amount of sodium alginate is 5 g.

[0052] Example 10

[0053] A preparation method of a yellowing-resistant oxidized PVC film, which is different from Example 8 in that during the preparation of modified almond shell powder, the input amount of almond shell powder is 16 g, the input amount of polyethylene glycol is 7 g, and the input amount of sodium alginate is 5 g.

[0054] Example 11

[0055] A preparation method of a yellowing-resistant oxidized PVC film, which is different from that of Example 10 in that: the input amount of modified talcum powder is 20 g, the input amount of PVC is 76 g, and the input amount of modified almond shell powder is 11 g.

[0056] Example 12

[0057] A preparation method of a yellowing-resistant oxidized PVC film, which is different from that of Example 10 in that: the input amount of modified talcum powder is 20 g, the input amount of PVC is 84 g, and the input amount of modified almond shell powder is 13 g.

[0058] Comparative example

[0059] Comparative example 1

[0060] A preparation method of a yellowing-resistant oxidized PVC film, which is different from that of Example 3 in that: the modified talcum powder is replaced with talcum powder in equal amount.

[0061] Comparative example 2

[0062] A preparation method of a yellowing-resistant oxidized PVC film, which is different from that of Example 3 in that: the modified talcum powder is replaced with titanium dioxide in equal amount.

[0063] Comparative example 3

[0064] A preparation method of a yellowing-resistant oxidized PVC film, which is different from that of Example 3 in that: the almond shell powder is replaced with titanium dioxide in equal amount.

[0065] Comparative example 4

[0066] A preparation method of a yellowing-resistant oxidized PVC film, which is different from that of Example 3 in that: the almond shell powder is replaced with coconut shell powder in equal amount.

[0067] Performance detection test:

[0068] Yellowing resistance test: Aging is carried out with ultraviolet light of 420 nm in a hot air box at high temperature and high humidity. After 250 h, the corresponding test samples are taken out of the oven, cooled to room temperature and sealed in aluminum-lined bags for testing. The yellow index of the samples obtained from Examples 1-12 and Comparative examples 1-4 is tested.

[0069] Tensile strength: The mechanical properties of the PVC films prepared in Examples 1-12 and Comparative examples 1-4 are tested according to GB / T 1040.3-2006, and the tensile strength of the aged PVC films is also tested.

[0070]

[0071]

[0072] From the data comparison of Examples 1-3 and Comparative Examples 1-4, it can be seen that PVC is the main component of the film. After modification, talcum powder has better dispersibility and compatibility, thus reducing yellowing caused by filler aggregation. Almond shell powder, as a natural filler, has a certain antioxidant effect due to the phenolic substances it contains, which helps to improve the yellowing resistance of the PVC film. The combined action of each component can improve the yellowing resistance of the PVC film. Through reasonable formulation design and processing technology, it is possible to slow down the yellowing process while maintaining the excellent physical properties of the PVC film.

[0073] From the data comparison of Examples 3-6, it can be seen that talcum powder, 3-mercaptopropyltrimethoxysilane, copper chloride, and polypropylene are used in combination. 3-mercaptopropyltrimethoxysilane can be grafted onto PVC to improve the compatibility between PVC and polypropylene, thereby further enhancing the tensile strength of the PVC film.

[0074] From the data comparison of Examples 6-8, it can be seen that sodium alginate, as a stabilizer, reduces the thermal degradation of PVC during processing and use. Almond shell powder contains phenolic substances and has a certain antioxidant effect, which helps to delay the yellowing of PVC. Mixing almond shell powder and sodium alginate, and then mixing with polyethylene glycol, can improve the mechanical strength of almond shell powder, thereby enhancing the mechanical strength of almond shell powder as a filler in PVC.

[0075] From the data comparison of Examples 8-10, it can be seen that when almond shell powder, polyethylene glycol, and sodium alginate are in a specific weight ratio, ammonium alginate has a large number of hydroxyl and carboxyl groups in its molecular weight, forms a hydrogel with polyethylene glycol, and covers almond shell powder. Almond shell powder is evenly dispersed in PVC, which helps to reduce the yellowing phenomenon caused by heat or light in PVC, and at the same time endows PVC with excellent tensile strength.

[0076] From the data comparison of Examples 10-12, it can be seen that the dispersibility and compatibility of modified talcum powder in PVC are improved after surface treatment, further enhancing the tensile strength of PVC. Modified almond shell powder can further improve the thermal stability of PVC, thus helping to reduce the yellowing phenomenon caused by filler aggregation; the combined use of modified talcum powder and modified almond shell powder can improve the yellowing resistance of PVC while enhancing its tensile strength.

[0077] The specific embodiments are only explanations of the present application and do not limit the present application. Those skilled in the art can make modifications to the embodiments without creative contributions according to their needs after reading this specification, but as long as they are within the scope of the claims of the present application, they are protected by the patent law.

Claims

1. A yellowing-resistant oxidized PVC film, characterized in that: It includes the following raw materials in parts by weight: 60 - 90 parts of PVC; 20 - 60 parts of plasticizer; 2 - 8 parts of calcium stearate; 10 - 30 parts of modified talc powder; 1 - 3 parts of antioxidant; 5 - 15 parts of almond shell powder; The modified talc powder is prepared by modifying the following raw materials: talc powder, ethanol, 3 - mercaptopropyltrimethoxysilane, copper chloride and polypropylene; The weight ratio of talc powder, 3 - mercaptopropyltrimethoxysilane, copper chloride and polypropylene is (1.6 - 1.8):1:(0.15 - 0.23):(0.6 - 0.7); The preparation method of the modified talc powder is: mix and stir 10 - 20 parts by weight of talc powder and 50 - 150 parts by weight of ethanol, add 5 - 15 parts by weight of 3 - mercaptopropyltrimethoxysilane, 1 - 5 parts by weight of copper chloride and 5 - 10 parts by weight of polypropylene after ultrasonic treatment, mix and stir, filter, wash and then dry to obtain the modified talc powder; The almond shell powder is modified almond shell powder, and the preparation method of the modified almond shell powder is: mix 3 - 9 parts by weight of sodium alginate with 10 - 30 parts by weight of water, then add 10 - 20 parts of almond shell powder and 5 - 10 parts by weight of polyethylene glycol, disperse ultrasonically, filter, dry and then grind to obtain the modified almond shell powder.

2. The anti-yellowing oxidized PVC film according to claim 1, wherein: The weight ratio of the almond shell powder, polyethylene glycol and sodium alginate is (2.4 - 3.2):(1.2 - 1.4):

1.

3. The oxidation-resistant PVC film resistant to yellowing according to claim 1, characterized in that: The degree of polymerization of the PVC is 1000 - 1100.

4. A yellowing-resistant oxidized PVC film according to claim 1, characterized in that: The weight ratio of the modified talc powder, PVC and modified almond shell powder is 1:(3.8 - 4.2):(0.55 - 0.65).

5. A yellowing-resistant oxidized PVC film according to claim 1, characterized in that: The plasticizer is one of dioctyl phthalate and diisooctyl phthalate.

6. The yellowing-resistant oxidized PVC film according to claim 1, characterized in that: The antioxidant is one of antioxidant 168 and antioxidant 1010.

7. A preparation method of a yellowing-resistant oxidized PVC film, characterized in that: To prepare a yellowing - resistant and oxidation - resistant PVC film according to any one of claims 1 - 6, it includes the following steps: mix and stir PVC, plasticizer, calcium stearate, modified talc powder, antioxidant and almond shell powder, continue to stir after cooling, calender and dry to obtain the yellowing - resistant and oxidation - resistant PVC film.

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