Production method of vehicle gauge grade MLCC release base film

Abstract

The invention discloses a production method of a vehicle gauge grade MLCC release base film. The base film comprises an outer layer, a middle layer and an inner layer. The outer layer is prepared from PET, silane coupling agent modified nano zinc oxide, organic silicon modified acrylate and an antioxidant; the middle layer is prepared from PET (Polyethylene Terephthalate), ethylene propylene diene monomer, nano silicon dioxide, organic montmorillonite and PP-g-MAH (Maleic Anhydride); the inner layer is composed of PET, a high-density polyethylene / butadiene styrene rubber composite modifier, graphene oxide and multi-walled carbon nanotubes. The prepared vehicle gauge grade MLCC release base film has excellent mechanical properties and thermal stability.

Description

Technical Field

[0001] The present invention relates to the technical field of BOPET films, and specifically to a method for producing an automotive-grade MLCC release base film. Background Art

[0002] Multilayer ceramic capacitors (MLCCs) play a vital role in ensuring the stable operation of automotive electronic systems. As a core material in MLCC manufacturing, automotive-grade MLCC release films must possess exceptional comprehensive performance, including excellent thermal stability to withstand high-temperature operating environments such as the vehicle engine compartment, strong mechanical properties to prevent damage under challenging operating conditions, excellent chemical stability to resist corrosion from various chemicals, and reliable release properties to ensure a smooth MLCC production process. However, existing MLCC release films exhibit numerous drawbacks when used in automotive applications. For example, under harsh conditions of high temperature and humidity, the film's dimensions can easily change, affecting the precision of the MLCC. Furthermore, the release properties can become unstable over extended use or under unusual operating conditions, making it difficult to separate the MLCC from the film, reducing production efficiency and increasing the defective rate. Therefore, developing a BOPET release film production method that meets the stringent requirements of automotive-grade MLCCs is of great practical significance. Summary of the Invention

[0003] In view of the above-mentioned defects of the prior art, the object of the present invention is to provide a method for producing an automotive-grade MLCC release base film.

[0004] To solve the above problems, the technical solution of the present invention is: a method for producing an automotive-grade MLCC release base film, the base film comprising an outer layer, an intermediate layer and an inner layer;

[0005] The outer layer is composed of PET, silane coupling agent modified nano zinc oxide, silicone modified acrylate, and antioxidant;

[0006] The middle layer is composed of PET, EPDM rubber, nano-silica, organic montmorillonite, and PP-g-MAH;

[0007] The inner layer is composed of PET, high-density polyethylene / styrene-butadiene rubber composite modifier, graphene oxide, and multi-walled carbon nanotubes;

[0008] The production method of automotive-grade MLCC release film includes the following steps:

[0009] (1) Weigh the raw materials according to the proportions of the outer layer, middle layer and inner layer components;

[0010] (2) The raw materials of the outer layer, middle layer and inner layer are mixed separately and sent into their respective extruders for mixing and plasticizing;

[0011] (3) The molten melts are fed into the die heads respectively, and the melts are combined in the die heads and then pass through the flat die head mouth to form a molten sheet;

[0012] (4) Using an air knife to attach the sheet to a chilled roller, the sheet is quenched to form an unshaped sheet, and then cooled in a water bath to form a cast sheet;

[0013] (5) The cast sheet is stretched to form a film;

[0014] (6) Coating the film surface with a carboxymethyl chitosan / M(OH)(OCH3)(M=Co, Ni) polyacrylic acid coating;

[0015] (7) Roll up the film.

[0016] Furthermore, the preparation method of the high-density polyethylene / styrene-butadiene rubber composite modifier is as follows: dry HDPE, SBR, and xylene solvent are placed in a container, heated and stirred until the HDPE and SBR are completely dissolved, a bridging agent is added, an initiator is added dropwise, the reaction is carried out at a constant temperature, and finally separated and dried to obtain the high-density polyethylene / styrene-butadiene rubber composite modifier.

[0017] Furthermore, step (6) includes the following steps:

[0018] (61) M(OH)(OCH3)(M=Co, Ni) was dispersed in deionized water and ultrasonicated for 30 min to obtain dispersion A. Carboxymethyl chitosan was dissolved in deionized water to obtain solution B. Dispersion A and solution B were mixed in a volume ratio of 1:4. The mixed solution was ultrasonicated for 15 min and stirred for 15 min, alternating for 4 times to obtain a positively charged coating solution C.

[0019] (62) Dissolving polyacrylic acid in deionized water to obtain a negatively charged coating solution D;

[0020] (63) The film was immersed in a polyethyleneimine solution for 5 min and then dried in a 60 °C oven for 20 min. The dried film was immersed in a polyacrylic acid solution for 5 min and then dried in a 60 °C oven for 20 min. After drying, the pretreated PET film was obtained.

[0021] (64) The pretreated PET film was immersed in the positively charged coating solution C for 1 min and then dried in a 60 °C oven. After drying, the PET film was immersed in the negatively charged coating solution D for 1 min and then dried in a 60 °C oven.

[0022] Furthermore, the inner layer of graphene oxide is prepared by dissolving graphene oxide in distilled water and stirring with a glass rod until the graphene oxide is completely dissolved, placing the graphene oxide aqueous solution in an ultrasonic cleaner for 12 hours to uniformly diffuse the graphene oxide in the aqueous solution, crushing the graphene oxide aqueous solution with an ultrasonic cell crusher for 6 hours, and freeze-drying the graphene oxide aqueous solution to obtain a fluffy graphene oxide sponge, which is placed in a planetary ball mill and crushed for 6 hours to obtain small-sized graphene oxide.

[0023] The components of the outer layer are as follows by mass ratio: PET 86%, silane coupling agent modified nano zinc oxide 4%, silicone modified acrylate 9%, antioxidant 1%;

[0024] The components of the middle layer are as follows by mass ratio: PET 77%, EPDM rubber 4%, nano-silica 6%, organic montmorillonite 7%, PP-g-MAH 6%;

[0025] The components of the inner layer are as follows by mass: PET 80%, high-density polyethylene / styrene-butadiene rubber composite modifier 19%, graphene oxide 0.4%, and multi-walled carbon nanotubes 0.6%.

[0026] The beneficial effects of the present invention are as follows: the outer layer has good antibacterial, scratch-resistant and chemical corrosion-resistant properties by adding nano zinc oxide, antioxidant and silicone-modified acrylate; the components of the middle layer work synergistically to improve the mechanical strength, flexibility, impact resistance, barrier properties and thermal stability of the base film; the combination of high-density polyethylene / styrene-butadiene rubber composite modifier, graphene oxide and multi-walled carbon nanotubes in the inner layer enhances the mechanical properties and thermal stability of the base film;

[0027] After coating the film surface with carboxymethyl chitosan / M(OH)(OCH3)(M=Co, Ni) polyacrylic acid coating, the flame retardancy of the film can be improved and the thermal stability of the film can be enhanced. DETAILED DESCRIPTION

[0028] In order to more intuitively and completely understand the technical solution of the present invention, a non-limiting description of the features is now provided as follows:

[0029] A method for producing an automotive-grade MLCC release base film, the base film comprising an outer layer, an intermediate layer, and an inner layer;

[0030] The outer layer is composed of PET, silane coupling agent modified nano zinc oxide, silicone modified acrylate, and antioxidant. The antioxidant is antioxidant 1098, and the nano zinc oxide is surface treated with silane coupling agent KH570.

[0031] The middle layer is composed of PET, EPDM rubber, nano-silica, organic montmorillonite, and PP-g-MAH, and the nano-silica is surface activated;

[0032] The inner layer is composed of PET, high-density polyethylene / styrene-butadiene rubber composite modifier, graphene oxide, and multi-walled carbon nanotubes;

[0033] The production method of automotive-grade MLCC release film includes the following steps:

[0034] (1) Weigh the raw materials according to the proportions of the outer layer, middle layer and inner layer components;

[0035] (2) The raw materials of the outer layer, middle layer and inner layer are mixed separately and sent into their respective extruders for mixing and plasticizing;

[0036] (3) The molten melts are fed into the die heads respectively, and the melts are combined in the die heads and then pass through the flat die head mouth to form a molten sheet;

[0037] (4) Using an air knife to attach the sheet to a chilled roller, the sheet is quenched to form an unshaped sheet, and then cooled in a water bath to form a cast sheet;

[0038] (5) The cast sheet is stretched to form a film;

[0039] (6) Coating the film surface with a carboxymethyl chitosan / M(OH)(OCH3)(M=Co, Ni) polyacrylic acid coating;

[0040] (7) Roll up the film.

[0041] The mass ratio of the outer layer, the middle layer and the inner layer is: 20% for the outer layer, 60% for the middle layer and 20% for the inner layer.

[0042] The preparation method of a high-density polyethylene / styrene-butadiene rubber composite modifier comprises: placing dried HDPE, SBR, and xylene solvent into a container, heating and stirring until the HDPE and SBR are completely dissolved, adding a bridging agent, and then dropwise adding an initiator. The mixture is reacted at a constant temperature, and finally separated and dried to obtain the high-density polyethylene / styrene-butadiene rubber composite modifier. The bridging agent is a compound containing an epoxy functional group, and the initiator is dibenzoyl peroxide.

[0043] Step (6) includes the following steps:

[0044] (61) M(OH)(OCH3)(M=Co, Ni) was dispersed in deionized water and ultrasonicated for 30 min to obtain dispersion A. Carboxymethyl chitosan was dissolved in deionized water to obtain solution B. Dispersion A and solution B were mixed in a volume ratio of 1:4. The mixed solution was ultrasonicated for 15 min and stirred for 15 min, alternating for 4 times to obtain a positively charged coating solution C.

[0045] (62) Dissolving polyacrylic acid in deionized water to obtain a negatively charged coating solution D;

[0046] (63) The film was immersed in a polyethyleneimine solution (0.1 wt%) for 5 min and then dried in a 60 °C oven for 20 min. The dried film was immersed in a polyacrylic acid solution (1 wt%) for 5 min and then dried in a 60 °C oven for 20 min. After drying, the pretreated PET film was obtained.

[0047] (64) The pretreated PET film was immersed in the positively charged coating solution C for 1 min and then dried in a 60 °C oven. After drying, the PET film was immersed in the negatively charged coating solution D for 1 min and then dried in a 60 °C oven.

[0048] The two-dimensional nanomaterial M(OH)(OCH3) plays a key role in improving the thermal stability of the sample. The metal components (Co / Ni) in the coating catalyze carbonization at high temperatures, contributing to improved flame retardancy. This is due to the combined effects of the "nanobarrier" effect of the two-dimensional nanomaterial M(OH)(OCH3) and the catalytic carbonization of elements such as Co and Ni.

[0049] The inner layer of graphene oxide was prepared by dissolving the graphene oxide in distilled water and stirring with a glass rod until the graphene oxide was completely dissolved. The graphene oxide solution was then ultrasonically cleaned for 12 hours to evenly disperse the graphene oxide in the solution. The solution was then pulverized with an ultrasonic cell crusher for 6 hours. After freeze-drying the graphene oxide solution, a fluffy sponge of graphene oxide was obtained. This sponge was then pulverized in a planetary ball mill for 6 hours to obtain small-sized graphene oxide. The small size of the graphene oxide facilitated its dispersion in the PET matrix. The two-dimensional graphene oxide and the one-dimensional multi-walled carbon nanotubes effectively connected the different dimensional materials, forming a network structure that increased the rigidity and strength of the PET.

[0050] The outer layer's components, by weight, are: 86% PET, 4% silane-coupling agent-modified nano-zinc oxide, 9% silicone-modified acrylate, and 1% antioxidant. The nano-zinc oxide provides antibacterial properties, the silicone-modified acrylate enhances the outer layer's scratch and chemical resistance, and the antioxidant prevents oxidation and degradation of the base film during processing and use.

[0051] The middle layer's components, by mass, are: PET 77%, EPDM 4%, nano-silica 6%, organic montmorillonite 7%, and PP-g-MAH 6%. EPDM effectively toughens the base film, improving its flexibility and impact resistance. Nano-silica enhances its mechanical strength, and organic montmorillonite improves its barrier properties and thermal stability.

[0052] The components of the inner layer are as follows by mass: PET 80%, high-density polyethylene / styrene-butadiene rubber composite modifier 19%, graphene oxide 0.4%, and multi-walled carbon nanotubes 0.6%. There are a certain amount of grafted and cross-linked epoxy functional groups and unreacted HDPE and SBR in the structure of the high-density polyethylene / styrene-butadiene rubber composite modifier. When the high-density polyethylene / styrene-butadiene rubber composite modifier is thermomechanically blended with PET, the presence of unreacted and free HDPE and SBR in the high-density polyethylene / styrene-butadiene rubber composite modifier gives it a certain fluidity, making it easy to fully fuse with the PET melt and disperse evenly. The epoxy functional groups in the high-density polyethylene / styrene-butadiene rubber composite modifier trigger a chemical reaction with the carboxyl and hydroxyl groups in the PET molecules. A certain amount of PET is connected to the HDPE and SBR in the high-density polyethylene / styrene-butadiene rubber composite modifier through bridging chains. In this way, when the material is impacted, the force can be well transmitted between different phases. The interface will not separate due to the chemical bond connection. The force is transmitted to the dispersed rubber phase, and the rubber phase undergoes large deformation to absorb more impact energy, thereby greatly improving the impact strength. Graphene oxide and multi-walled carbon nanotubes have a synergistic reinforcement effect. The addition of graphene oxide and multi-walled carbon nanotubes can form a network structure in the polymer matrix, hindering the movement of PET molecular chains and slowing down the thermal decomposition rate of the molecular chains. The large specific surface area and functional groups on the active surface of graphene oxide and multi-walled carbon nanotubes can interact with PET molecules to form physical or chemical crosslinks, preventing the thermal decomposition of PET molecular chains and improving the thermal stability of the material.

[0053] The outer layer of the present invention has good antibacterial, scratch-resistant and chemical corrosion-resistant properties by adding nano zinc oxide, antioxidants and silicone-modified acrylate; the components of the middle layer work synergistically to improve the mechanical strength, flexibility, impact resistance, barrier properties and thermal stability of the base film; the combination of high-density polyethylene / styrene-butadiene rubber composite modifier, graphene oxide and multi-walled carbon nanotubes in the inner layer enhances the mechanical properties and thermal stability of the base film;

[0054] Coating the film surface with a carboxymethyl chitosan / M(OH)(OCH3)(M=Co, Ni) polyacrylic acid coating improves the film's flame retardancy and enhances its thermal stability. This invention overcomes the interfacial compatibility issues often associated with blending flame retardants with polymer matrices to improve flame retardancy, which can reduce material uniformity and stability.

Claims

1. A method for producing an automotive-grade MLCC release film, characterized in that: The basement membrane includes an outer layer, a middle layer, and an inner layer; The outer layer is composed of PET, silane coupling agent modified nano zinc oxide, silicone modified acrylate, and antioxidant; The middle layer is composed of PET, EPDM rubber, nano-silica, organic montmorillonite, and PP-g-MAH; The inner layer is composed of PET, high-density polyethylene / styrene-butadiene rubber composite modifier, graphene oxide, and multi-walled carbon nanotubes; The production method comprises the following steps: (1) Weigh the raw materials according to the proportions of the outer layer, middle layer and inner layer components; (2) The raw materials of the outer layer, middle layer and inner layer are mixed separately and sent into their respective extruders for mixing and plasticizing; (3) The molten melts are fed into the die heads respectively, and the melts are combined in the die heads and then pass through the flat die head mouth to form a molten sheet; (4) Using an air knife to attach the sheet to a chilled roller, the sheet is quenched to form an unshaped sheet, and then cooled in a water bath to form a cast sheet; (5) The cast sheet is stretched to form a film; (6) Coating the film surface with a carboxymethyl chitosan / M(OH)(OCH3)(M=Co, Ni) polyacrylic acid coating; (7) Roll up the film.

2. The method for producing an automotive-grade MLCC release film according to claim 1, wherein: The preparation method of the high-density polyethylene / styrene-butadiene rubber composite modifier is as follows: adding dried HDPE, SBR and xylene solvent into a container, heating and stirring, and after the HDPE and SBR are completely dissolved, adding a bridging agent, adding an initiator dropwise, reacting at a constant temperature, and finally separating and drying to obtain the high-density polyethylene / styrene-butadiene rubber composite modifier.

3. The method for producing an automotive-grade MLCC release base film according to claim 1, wherein: Step (6) includes the following steps: (61) M(OH)(OCH3)(M=Co, Ni) was dispersed in deionized water and ultrasonicated for 30 min to obtain dispersion A. Carboxymethyl chitosan was dissolved in deionized water to obtain solution B. Dispersion A and solution B were mixed in a volume ratio of 1:

4. The mixed solution was ultrasonicated for 15 min and stirred for 15 min, alternating for 4 times to obtain a positively charged coating solution C. (62) Dissolving polyacrylic acid in deionized water to obtain a negatively charged coating solution D; (63) The film was immersed in a polyethyleneimine solution for 5 min and then dried in a 60 °C oven for 20 min. The dried film was immersed in a polyacrylic acid solution for 5 min and then dried in a 60 °C oven for 20 min. After drying, the pretreated PET film was obtained. (64) The pretreated PET film was immersed in the positively charged coating solution C for 1 min and then dried in a 60 °C oven. After drying, the PET film was immersed in the negatively charged coating solution D for 1 min and then dried in a 60 °C oven.

4. The method for producing an automotive-grade MLCC release base film according to claim 1, characterized in that: The preparation method of the inner layer of graphene oxide is as follows: dissolve graphene oxide in distilled water and stir with a glass rod until the graphene oxide is completely dissolved, place the graphene oxide aqueous solution in an ultrasonic cleaner and ultrasonicate for 12 hours to make the graphene oxide evenly diffuse in the aqueous solution, use an ultrasonic cell crusher to crush the graphene oxide aqueous solution for 6 hours, and after freeze-drying the graphene oxide aqueous solution, a fluffy graphene oxide sponge is obtained, which is placed in a planetary ball mill and crushed for 6 hours to obtain small-sized graphene oxide.

5. The method for producing an automotive-grade MLCC release film according to claim 1, wherein: The components of the outer layer are as follows by mass ratio: PET 86%, silane coupling agent modified nano zinc oxide 4%, silicone modified acrylate 9%, antioxidant 1%; The components of the middle layer are as follows by mass ratio: PET 77%, EPDM rubber 4%, nano-silica 6%, organic montmorillonite 7%, PP-g-MAH 6%; The components of the inner layer are as follows by mass: PET 80%, high-density polyethylene / styrene-butadiene rubber composite modifier 19%, graphene oxide 0.4%, and multi-walled carbon nanotubes 0.6%.