阅读说明：本技术 一种耐热型lcp薄膜及其制备方法 (Heat-resistant LCP film and preparation method thereof ) 是由 张东宝 张奇 于 2020-06-11 设计创作，主要内容包括：本发明提供了一种耐热型LCP薄膜及其制备方法,该耐热型LCP薄膜由以下原料制备而成：聚甲基硅氧烷,聚偏二氟乙烯膜,丙烯氧基苯甲酸,[4-(烯丙氧基)苯甲酰基]-4-甲氧基苯基单体。本发明实施例制备的耐热型LCP薄膜具有较好的综合性能,耐热性能好。因此,能够满足电子器件、精密器械零件、医疗器械等需要热稳定性薄膜的领域,实用性高。(The invention provides a heat-resistant LCP film and a preparation method thereof, wherein the heat-resistant LCP film is prepared from the following raw materials: polymethylsiloxane, polyvinylidene fluoride membrane, allyloxybenzoic acid, [4- (allyloxy) benzoyl ] -4-methoxyphenyl monomer. The heat-resistant LCP film prepared by the embodiment of the invention has better comprehensive performance and good heat resistance. Therefore, the film can satisfy the fields requiring a heat-stable film such as electronic devices, precision equipment parts, medical equipment, and the like, and has high practicability.)

1. A heat-resistant LCP film is characterized by being prepared from the following raw materials: polymethylsiloxane, polyvinylidene fluoride membrane, allyloxybenzoic acid, [4- (allyloxy) benzoyl ] -4-methoxyphenyl monomer.

2. The LCP film of claim 1, which is prepared from the following raw materials in parts by weight: 50-60 parts of polymethylsiloxane, 40-50 parts of polyvinylidene fluoride film, 20-30 parts of allyloxybenzoic acid and 10-20 parts of [4- (allyloxy) benzoyl ] -4-methoxyphenyl monomer.

3. The LCP film of claim 1, wherein the allyloxybenzoic acid is prepared by the following method: dissolving 30g of p-hydroxybenzoic acid in 60ml of methanol, slowly adding dropwise to 100ml of methanol containing 40g of potassium hydroxide, stirring the resulting mixture at room temperature for 2h, adding 30g of 3-chloro-1-propene to the mixture, refluxing under stirring for 6h, removing the solvent and unreacted 3-chloro-1-propene with a rotary evaporator, dissolving the resulting solid product in distilled water, washing with diethyl ether for 3 times, and neutralizing with hydrochloric acid to cause precipitation of the product, recovering the crude acid by suction filtration, and purifying by recrystallization twice from 2-propanol, and vacuum-drying the purified propenyloxybenzoic acid at room temperature to obtain the final product.

4. The LCP film of claim 1, wherein the [4- (allyloxy) benzoyl ] -4-methoxyphenyl monomer is prepared by the following method: 10g of 4- (allyloxy) benzoic acid was added to 500ml of thionyl chloride, stirred for 2 hours until the reaction was completely dissolved, excess thionyl chloride was removed using a rotary evaporator to obtain liquid acid chloride, the obtained solution was dropwise added to 100ml of dichloromethane containing 8g of 4-methoxyphenol, stirred at room temperature for 5 hours, the solid product obtained after removal of the solvent using the rotary evaporator was dissolved in ethyl acetate and washed several times with an aqueous NaOH solution, the solvent was removed by using the rotary evaporator, the obtained crude product was purified by recrystallization twice with ethanol, and finally the finally obtained [4- (allyloxy) benzoyl ] -4-methoxyphenyl monomer was dried under vacuum at room temperature.

5. The LCP film of claim 1, which is prepared from the following raw materials in parts by weight: 55 parts of polymethylsiloxane, 45 parts of polyvinylidene fluoride film, 25 parts of allyloxybenzoic acid and 15 parts of [4- (allyloxy) benzoyl ] -4-methoxyphenyl monomer.

6. A process for the preparation of a heat resistant LCP film as claimed in any of claims 1 to 5 comprising the steps of:

s1: before use, the corresponding weight parts of polymethylsiloxane, polyvinylidene fluoride film, allyloxybenzoic acid and [4- (allyloxy) benzoyl ] -4-methoxyphenyl monomer are dried for 5-7 hours at the temperature of 70-80 ℃ in the air;

s2: then mixing the materials, adding the mixture into an extruder, wherein the extruder consists of a screw and a heated screw cylinder, the screw is driven by a motor to rotate and is divided into a feeding section, a melting section and a homogenizing section according to efficiency, the mixed materials are gradually compacted in the feeding section, air carried in the mixed materials is discharged from a feeding port and gradually melted into a molten state in the melting section, and the molten state mixture is extruded at a discharge rate of 17-19 kg/hour in the homogenizing section; in order to remove impurities in the molten mixture, a filter is connected in series with the extruder; the filter consists of a filter element, a machine barrel and a heater; the filter core mainly by: a flange, a core column, a filter plate, a metal frame and the like;

s3: after the material comes out of the filter, the material enters a die head through a melting pipeline, passes through a runner and finally flows out of a die gap to form a thick film, and a plurality of differential bolts are arranged around the die gap and used for initially adjusting the size of the die gap; the die head is a die lip heating type automatic adjusting die head, the thickness of a cast sheet can be measured by an online thickness gauge during production, and the measured thickness data is calculated and processed to generate a control signal which is fed back to a die lip heater to adjust the heating power; casting the melt uniformly distributed by the die head onto a casting sheet roller, and rapidly cooling the casting sheet roller to form a casting sheet; after the thickness of the cast sheet is measured by a thickness gauge, the cast sheet enters a longitudinal drawing system and a transverse drawing system, and a film is prepared by a blow molding method under the conditions of the longitudinal drawing multiple of 2-4 times and the transverse drawing multiple of 5-8 times.

7. The method of claim 6, wherein the drying temperature is 75 ℃.

8. The method of claim 6, wherein the drying time is 6 hours.

9. The method of claim 6, wherein the discharge rate is 18 kg/hour.

10. The method of claim 6, wherein the cross stretch is 6 times and the longitudinal stretch is 3 times.

Technical Field

The invention relates to the field of films, in particular to a heat-resistant LCP film and a preparation method thereof.

Background

At present, the synthesis of LCP (liquid crystal polymer) is mainly polycondensation reaction, and the synthesized LCP (liquid crystal polymer) mainly has: main chain type polyamides, polyesters, polyethers, polythiazole imidazoles, and the like; examples of the side chain type include polyisocyanates, polyazos, polydimethylsiloxanes, and polypropylene (PP) acid esters. In addition, there are some polymer liquid crystals having a special mechanism. The LCP (liquid crystal polymer) has outstanding heat resistance compared with other organic polymer materials.

Japanese patent application laid-open No. 10-157010 discloses that when the thermal expansion coefficient of the laminated film is larger than that of the surface mounting component, the thermal expansion coefficient of the film is reduced to 18X 10-6 cm/cm/DEG C at the maximum by performing a heat treatment in a temperature range from 140 ℃ lower than the melting point of the film to the melting point, and when the thermal expansion coefficient of the laminated film is smaller than that of the surface mounting component, the thermal expansion coefficient of the film is increased by performing a heat treatment in a temperature range from the melting point of the film to 20 ℃ higher than the melting point. Further, US5,529,740 discloses various properties of a film obtained by heating a thermoplastic liquid crystal polymer film to a temperature equal to or higher than its melting point in a state where the thermoplastic liquid crystal polymer film is in contact with a support, and cooling and solidifying the molten polymer, and describes that the thermal expansion coefficient of the film is improved by performing the above-mentioned treatment of melting and solidifying. The above methods are all to obtain heat-resistant films by treating the films and further increasing the thermal expansion coefficient of the films, but the above methods can only improve the heat resistance of the films to a certain extent, and cannot meet the requirement of high heat resistance of LCP in the use process, and the methods need to be improved from the use materials.

Disclosure of Invention

In view of the above, in order to solve the above problems, a heat-resistant LCP film and a method for preparing the same are provided, wherein the heat-resistant LCP film is prepared from the following raw materials: polymethylsiloxane, polyvinylidene fluoride membrane, allyloxybenzoic acid, [4- (allyloxy) benzoyl ] -4-methoxyphenyl monomer.

The LCP film is prepared from the following raw materials in parts by weight: 50-60 parts of polymethylsiloxane, 40-50 parts of polyvinylidene fluoride film, 20-30 parts of allyloxybenzoic acid and 10-20 parts of [4- (allyloxy) benzoyl ] -4-methoxyphenyl monomer.

The preparation method of the allyloxybenzoic acid comprises the following steps: dissolving 30g of p-hydroxybenzoic acid in 60ml of methanol, slowly adding dropwise to 100ml of methanol containing 40g of potassium hydroxide, stirring the resulting mixture at room temperature for 2h, adding 30g of 3-chloro-1-propene to the mixture, refluxing under stirring for 6h, removing the solvent and unreacted 3-chloro-1-propene with a rotary evaporator, dissolving the resulting solid product in distilled water, washing with diethyl ether for 3 times, and neutralizing with hydrochloric acid to cause precipitation of the product, recovering the crude acid by suction filtration, and purifying by recrystallization twice from 2-propanol, and vacuum-drying the purified propenyloxybenzoic acid at room temperature to obtain the final product.

The preparation method of the [4- (allyloxy) benzoyl ] -4-methoxyphenyl monomer comprises the following steps: 10g of 4- (allyloxy) benzoic acid was added to 500ml of thionyl chloride, stirred for 2 hours until the reaction was completely dissolved, excess thionyl chloride was removed using a rotary evaporator to obtain liquid acid chloride, the obtained solution was dropwise added to 100ml of dichloromethane containing 8g of 4-methoxyphenol, stirred at room temperature for 5 hours, the solid product obtained after removal of the solvent using the rotary evaporator was dissolved in ethyl acetate and washed several times with an aqueous NaOH solution, the solvent was removed by using the rotary evaporator, the obtained crude product was purified by recrystallization twice with ethanol, and finally the finally obtained [4- (allyloxy) benzoyl ] -4-methoxyphenyl monomer was dried under vacuum at room temperature.

The LCP film is prepared from the following raw materials in parts by weight: 55 parts of polymethylsiloxane, 45 parts of polyvinylidene fluoride film, 25 parts of allyloxybenzoic acid and 15 parts of [4- (allyloxy) benzoyl ] -4-methoxyphenyl monomer.

The preparation method of the heat-resistant LCP film comprises the following steps: s1: before use, the corresponding weight parts of polymethylsiloxane, polyvinylidene fluoride film, allyloxybenzoic acid and [4- (allyloxy) benzoyl ] -4-methoxyphenyl monomer are dried for 5-7 hours at the temperature of 70-80 ℃ in the air; s2: then mixing the materials, adding the mixture into an extruder, wherein the extruder consists of a screw and a heated screw cylinder, the screw is driven by a motor to rotate and is divided into a feeding section, a melting section and a homogenizing section according to efficiency, the mixed materials are gradually compacted in the feeding section, air carried in the mixed materials is discharged from a feeding port and gradually melted into a molten state in the melting section, and the molten state mixture is extruded at a discharge rate of 17-19 kg/hour in the homogenizing section; in order to remove impurities in the molten mixture, a filter is connected in series with the extruder; the filter consists of a filter element, a machine barrel and a heater; the filter core mainly by: a flange, a core column, a filter plate, a metal frame and the like; s3: after the material comes out of the filter, the material enters a die head through a melting pipeline, passes through a runner and finally flows out of a die gap to form a thick film, and a plurality of differential bolts are arranged around the die gap and used for initially adjusting the size of the die gap; the die head is a die lip heating type automatic adjusting die head, the thickness of a cast sheet can be measured by an online thickness gauge during production, and the measured thickness data is calculated and processed to generate a control signal which is fed back to a die lip heater to adjust the heating power; casting the melt uniformly distributed by the die head onto a casting sheet roller, and rapidly cooling the casting sheet roller to form a casting sheet; after the thickness of the cast sheet is measured by a thickness gauge, the cast sheet enters a longitudinal drawing system and a transverse drawing system, and a film is prepared by a blow molding method under the conditions of the longitudinal drawing multiple of 2-4 times and the transverse drawing multiple of 5-8 times.

Wherein the drying temperature is 75 ℃, the drying time is 6 hours, the discharge amount is 18 kg/hour, the transverse stretching multiple is 6 times, and the longitudinal stretching multiple is 3 times.

The invention has the beneficial effects that:

the heat-resistant liquid crystal polymer film prepared by the invention is preferably polymethyl siloxane, polyvinylidene fluoride film, allyloxybenzoic acid and [4- (allyloxy) benzoyl ] -4-methoxyphenyl monomer, and the components have synergistic effect, so that the prepared film has both mechanical property and thermal property, can meet the field of electronic devices, precision apparatus parts, medical apparatuses and the like needing heat-stable films, and has high practicability.

Drawings

The accompanying drawings, which are included to provide a further understanding of the disclosed subject matter, are incorporated in and constitute a part of this specification. The drawings illustrate the implementations of the disclosed subject matter and, together with the detailed description, serve to explain the principles of implementations of the disclosed subject matter. No attempt is made to show structural details of the disclosed subject matter in more detail than is necessary for a fundamental understanding of the disclosed subject matter and various modes of practicing the same.

FIG. 1 is a diagram of the preparation process of a heat-resistant LCP film;

Detailed Description

The advantages, features and methods of accomplishing the same will become apparent from the drawings and the detailed description that follows.