阅读说明：本技术 一种低介电短切玻璃纤维浸润剂及制备方法 (Low-dielectric chopped glass fiber impregnating compound and preparation method thereof ) 是由 焦晓芳 宁祥春 张海洋 于 2021-01-21 设计创作，主要内容包括：本发明提供了一种低介电短切玻璃纤维浸润剂及制备方法,包括以下组分：主成膜剂、辅助成膜剂、润滑剂、偶联剂、pH调节剂和去离子水,主成膜剂由分子量为4000-6000的高分子量双酚A型环氧树脂乳液和分子量为20000-40000的聚氨酯乳液组成,辅助成膜剂是分子量为1000-1400的中分子量双酚A型环氧树脂乳液。本发明浸润剂用于玻璃纤维的拉制过程,提高了短切长度3mm、单丝直径5-10μm的低介电短切玻璃纤维的硬挺性、集束性、分散性和抗静电性；在玻璃纤维拉制过程中能够减少玻璃纤维与机械部件的摩擦系数,提升玻璃纤维的强度,同时提高了采用本发明浸润剂所拉制出来的玻璃纤维制成的复合材料的力学性能。(The invention provides a low-dielectric chopped glass fiber impregnating compound and a preparation method thereof, wherein the impregnating compound comprises the following components: the main film-forming agent consists of high molecular weight bisphenol A epoxy resin emulsion with the molecular weight of 4000-6000 and polyurethane emulsion with the molecular weight of 20000-40000, and the auxiliary film-forming agent is medium molecular weight bisphenol A epoxy resin emulsion with the molecular weight of 1000-1400. The impregnating compound is used in the drawing process of glass fibers, and improves the stiffness, bundling property, dispersibility and antistatic property of low dielectric chopped glass fibers with the chopped length of 3mm and the monofilament diameter of 5-10 mu m; the friction coefficient between the glass fiber and a mechanical part can be reduced in the process of drawing the glass fiber, the strength of the glass fiber is improved, and the mechanical property of a composite material made of the glass fiber drawn by the impregnating compound is improved.)

1. A low-dielectric chopped glass fiber impregnating compound is characterized by comprising the following components: the main film-forming agent is a mixture consisting of high molecular weight bisphenol A epoxy resin emulsion and polyurethane emulsion, the molecular weight of bisphenol A epoxy resin in the high molecular weight bisphenol A epoxy resin emulsion is 4000-6000, the molecular weight of polyurethane in the polyurethane emulsion is 20000-40000, the auxiliary film-forming agent is medium molecular weight bisphenol A epoxy resin emulsion, and the molecular weight of bisphenol A epoxy resin in the medium molecular weight bisphenol A epoxy resin emulsion is 1000-40000.

2. The low dielectric chopped glass fiber sizing agent according to claim 1, wherein said lubricant comprises lubricant A and lubricant B, said lubricant A being one of an imidazoline cationic lubricant, a combination of an imidazoline cationic lubricant and a non-ionic lubricant, and said lubricant B being a silicone lubricant.

3. The low dielectric chopped glass fiber sizing agent according to claim 2, wherein the mass ratio of the imidazoline cationic lubricant to the nonionic lubricant in the formulation of the imidazoline cationic lubricant to the nonionic lubricant is (1:1.5) - (1: 3.5).

4. The low-dielectric chopped glass fiber impregnating compound according to claim 2, wherein the mass percentage of each component in the impregnating compound is as follows: 17-21% of main film-forming agent, 1-5% of auxiliary film-forming agent, 0.01-0.1% of lubricant A, 0.3-1.2% of organic silicon lubricant, 0.3-1.2% of coupling agent, 0.04-0.1% of pH regulator and the balance of deionized water.

5. The low-dielectric chopped glass fiber impregnating compound according to claim 4, wherein the mass percentage of each component in the impregnating compound is as follows: 20% of main film forming agent, 2% of auxiliary film forming agent, 0.05% of lubricant A, 0.6% of organic silicon lubricant, 0.4% of coupling agent, 0.05% of pH regulator and the balance of deionized water.

6. The low-dielectric chopped glass fiber impregnating compound according to claim 1, wherein the mass ratio of the high-molecular-weight bisphenol A epoxy resin emulsion to the polyurethane emulsion is (12:1) - (10: 1).

7. The low-dielectric chopped strand glass fiber sizing agent of claim 1, wherein the coupling agent is one or both of silane coupling agents KH570 or 6032.

8. The low-dielectric chopped glass fiber impregnating compound according to claim 1, wherein one or two of glacial acetic acid or citric acid is adopted as the pH regulator.

9. A method for preparing a low dielectric chopped strand glass fiber sizing agent according to any one of claims 2 to 5, comprising the steps of:

(1) mixing a pH regulator with deionized water, adding a coupling agent, stirring, and standing to obtain a coupling agent diluent;

(2) mixing an organic silicon lubricant and deionized water, and stirring to obtain an organic silicon lubricant diluent;

(3) mixing the lubricant A with deionized water, and stirring to obtain a lubricant A diluent;

(4) mixing the main film forming agent, the auxiliary film forming agent and deionized water, and stirring to obtain a film forming agent diluent;

(5) and (2) adding deionized water into the preparation kettle, then adding the coupling agent diluent obtained in the step (1) into the preparation kettle, stirring, then sequentially adding the diluents obtained in the steps (2), (3) and (4) into the preparation kettle, and finally adding deionized water to reach the required solid content.

10. The method for preparing the low dielectric chopped glass fiber impregnating compound according to claim 9, characterized by comprising the following steps:

(1) and (2) mixing a pH regulator and deionized water according to a mass ratio of 1: (2-3) mixing, adding a coupling agent, stirring at the stirring speed of 60-80prm for 15-20min, and standing at 0-10 ℃ for 1-4h to obtain a coupling agent diluent;

(2) mixing the organic silicon lubricant and deionized water according to the mass ratio of 1 (1-2), stirring at the stirring speed of 60-80prm for 10-20min to obtain an organic silicon lubricant diluent;

(3) mixing the lubricant A with deionized water at 35-90 ℃ according to the mass ratio of 1 (5-20), stirring at the stirring speed of 60-80rpm for 5-10min to obtain a lubricant A diluent;

(4) mixing a main film-forming agent, an auxiliary film-forming agent and deionized water, wherein the mass ratio of the total mass of the main film-forming agent and the auxiliary film-forming agent to the deionized water is 1:1-1:1.2, stirring at a stirring speed of 60-80prm for 10-20min to obtain a film-forming agent diluent;

(5) adding deionized water accounting for 40-50% of the total weight of the impregnating compound into a preparation kettle, adding the coupling agent diluent obtained in the step (1) into the preparation kettle, stirring at the stirring speed of 60-80prm for 10-20 minutes, sequentially adding the diluents prepared in the steps (2), (3) and (4) into the preparation kettle, and finally adding deionized water until the solid content is 9-13%.

Technical Field

The invention relates to the technical field of impregnating compounds, in particular to a low-dielectric chopped glass fiber impregnating compound and a preparation method thereof.

Background

The glass fiber is a brittle material, and the impregnating compound is required to be coated during drawing so as to meet the requirements of drawing and subsequent production and finally meet the mechanical property and process requirements of a reinforced material. The development of glass fiber is nowadays similar to the varieties of the glass fiber with full meshes, and the glass fiber also has wide application fields, and depends on the key functions of continuous improvement of the quality of the impregnating compound and continuous increase of the varieties to some extent.

Since the birth of the last fifties of the last century, glass fiber factories in China continue to use original Susan paraffin emulsion as a drawing sizing agent until the middle seventies, and both textile glass fiber drawing and reinforced glass fiber drawing are adopted. Most of foreign impregnating compounds are special for one dose, even according to the special requirements of a certain user, while one dose is multiple for China, and the amount of the impregnating compound is unchanged for years. The hardness, bundling property, banding property, dispersibility and smoothness of the textile yarn and the reinforcing yarn do not meet the quality standard, and the technical performance requirements of deep processing and textile and reinforcing glass fiber products can not be met. Therefore, the impregnating compound has been a research subject to be solved for a long time, which restricts the improvement of the industrial yield and quality of the glass fiber and the development of the variety in China.

Chopped glass fibers are a large class of applications in glass fiber products, primarily as reinforcing materials such as reinforced thermosets and thermoplastics, and other uses, and their fields of application are expanding and increasing in number. The chopped glass fiber is formed by processing continuous glass fiber through a chopping machine, and the main length specification is as follows: 3mm, 4.5mm, 6mm, 12mm, 18mm, 24mm, etc. The main indexes of the chopped glass fiber strands used as the reinforcing materials are as follows: the water content is less than 1 percent, the long fiber content is less than 2 percent, the monofilament diameter is 11-13 mu m, the stiffness and the dispersibility are good, and the processing technology and the performance of the product are met.

The monofilament diameter of the low dielectric chopped glass fiber with the diameter of 3mm on the market at present is 11-13 mu m, while the low dielectric chopped glass fiber with the monofilament diameter of 5-10 mu m has poor stiffness, dispersibility and antistatic property, and the product has low mechanical property and low mechanical property.

Disclosure of Invention

The invention aims to provide a low-dielectric chopped glass fiber impregnating compound, which is applied to the drawing process of glass fibers, improves the stiffness of the low-dielectric glass fibers, overcomes the defects of poor dispersibility and antistatic property, and improves the mechanical property, mechanical property and appearance property of low-dielectric glass fiber products.

The invention provides a low-dielectric chopped glass fiber impregnating compound which comprises the following components in parts by weight: the main film-forming agent is a mixture consisting of high molecular weight bisphenol A epoxy resin emulsion and polyurethane emulsion, the molecular weight of bisphenol A epoxy resin in the high molecular weight bisphenol A epoxy resin emulsion is 4000-6000, the molecular weight of polyurethane in the polyurethane emulsion is 20000-40000, the auxiliary film-forming agent is medium molecular weight bisphenol A epoxy resin emulsion, and the molecular weight of bisphenol A epoxy resin in the medium molecular weight bisphenol A epoxy resin emulsion is 1000-40000.

The invention adopts bisphenol A epoxy resin emulsion with the molecular weight of 4000-6000 and polyurethane emulsion with the molecular weight of 20000-40000 as main film forming agents, the mass ratio of the bisphenol A epoxy resin emulsion to the polyurethane emulsion is (12:1) - (10:1), and the polyurethane emulsion is more preferably 10:1, and the impregnating compound prepared by adopting the main film forming agents can ensure that the dispersibility of glass fibers is better and the impregnating compound can better accord with the mechanical property of chopped glass fiber products when being applied to the drawing process of the glass fibers. According to the invention, the bisphenol A epoxy resin emulsion with the molecular weight of 1000-1400-plus-one is used as an auxiliary film-forming agent, and the main film-forming agent and the auxiliary film-forming agent act synergistically, so that the prepared glass fiber obtained by drawing the sizing agent has better dispersibility, the mechanical property is improved, the stiffness of the glass fiber yarn produced by using the sizing agent can be improved, and the bundling property of the glass fiber is better optimized.

The bisphenol A epoxy resin emulsion with the molecular weight of 4000-6000 of bisphenol A epoxy resin is a commercial product with the molecular weight of 4000-6000 of bisphenol A epoxy resin in the bisphenol A epoxy resin emulsion. The bisphenol A epoxy resin emulsion with the molecular weight of 1000-1400 of the bisphenol A epoxy resin is a commercial product with the molecular weight of the bisphenol A epoxy resin in the bisphenol A epoxy resin emulsion of 1000-1400. The polyurethane emulsion with the polyurethane molecular weight of 20000-40000 refers to the polyurethane emulsion with the polyurethane molecular weight of 20000-40000, and is a commercial product.

The low-dielectric chopped glass fiber impregnating compound is mainly used in the drawing process of glass fibers, preferably, the lubricant comprises a lubricant A and a lubricant B, wherein the lubricant A is one of imidazoline cationic lubricant, imidazoline cationic lubricant and nonionic lubricant compound, and the lubricant B is organosilicon lubricant.

Preferably, the mass ratio of the imidazoline cationic lubricant to the nonionic lubricant in the compound of the imidazoline cationic lubricant to the nonionic lubricant is (1:1.5) - (1:3.5), more preferably 1:2.1, and the imidazoline cationic lubricant and the nonionic lubricant are both commercially available products.

By adopting the compounding action of the lubricant A and the lubricant B, the obtained impregnating compound can reduce the friction coefficient between the glass fiber and a mechanical part in the glass fiber drawing process, and the glass fiber is not easy to break in the drawing process, so that the drawing is smoothly carried out.

Preferably, the mass percentage of each component in the impregnating compound is as follows: 17-21% of main film-forming agent, 1-5% of auxiliary film-forming agent, 0.01-0.1% of lubricant A, 0.3-1.2% of organic silicon lubricant, 0.3-1.2% of coupling agent, 0.04-0.1% of pH regulator and the balance of deionized water.

Preferably, the mass percentage of each component in the impregnating compound is as follows: 20% of main film forming agent, 2% of auxiliary film forming agent, 0.05% of lubricant A, 0.6% of organic silicon lubricant, 0.4% of coupling agent, 0.05% of pH regulator and the balance of deionized water. The sizing agent obtained by the proportion is applied to the drawing process of glass fibers, so that the bundling property of the glass fibers can be better improved, the bundling property of the glass fibers is kept when the glass fibers are chopped, the glass fibers are not easy to scatter, and the requirement of chopping 3mm can be met.

Preferably, the coupling agent is one or both of silane coupling agents KH570 or 6032.

Preferably, one or two of glacial acetic acid or citric acid is/are adopted as the pH regulator.

The preparation method of the low-dielectric chopped fiber impregnating compound comprises the following steps:

(1) mixing a pH regulator with deionized water, adding a coupling agent, stirring, and standing to obtain a coupling agent diluent;

(2) mixing an organic silicon lubricant and deionized water, and stirring to obtain an organic silicon lubricant diluent;

(3) mixing the lubricant A with deionized water, and stirring to obtain a lubricant A diluent;

(4) mixing the main film forming agent, the auxiliary film forming agent and deionized water, and stirring to obtain a film forming agent diluent;

(5) and (2) adding deionized water into the preparation kettle, then adding the coupling agent diluent obtained in the step (1) into the preparation kettle, stirring, then sequentially adding the diluents obtained in the steps (2), (3) and (4) into the preparation kettle, and finally adding deionized water to reach the required solid content.

Preferably, the preparation method of the low-dielectric chopped fiber impregnating compound comprises the following steps:

(1) and (2) mixing a pH regulator and deionized water according to a mass ratio of 1: (2-3) mixing, adding a coupling agent, stirring at the stirring speed of 60-80prm for 15-20min, and standing at 0-10 ℃ for 1-4h to obtain a coupling agent diluent;

(2) mixing the organic silicon lubricant and deionized water according to the mass ratio of 1 (1-2), stirring at the stirring speed of 60-80prm for 10-20min to obtain an organic silicon lubricant diluent;

(3) mixing the lubricant A with deionized water at 35-90 ℃ according to the mass ratio of 1 (5-20), stirring at the stirring speed of 60-80rpm for 5-10min to obtain a lubricant A diluent;

(4) mixing a main film-forming agent, an auxiliary film-forming agent and deionized water, wherein the mass ratio of the total mass of the main film-forming agent and the auxiliary film-forming agent to the deionized water is 1:1-1:1.2, stirring at a stirring speed of 60-80prm for 10-20min to obtain a film-forming agent diluent;

(5) adding deionized water accounting for 40-50% of the total weight of the impregnating compound into a preparation kettle, adding the coupling agent diluent obtained in the step (1) into the preparation kettle, stirring at the stirring speed of 60-80prm for 10-20 minutes, sequentially adding the diluents prepared in the steps (2), (3) and (4) into the preparation kettle, and finally adding deionized water until the solid content is 9-13%.

The invention has the beneficial effects that:

(1) the low-dielectric chopped glass fiber impregnating compound is used for the drawing process of glass fibers, and improves the stiffness, the convergence, the dispersibility and the antistatic property of low-dielectric chopped glass fibers with the chopped length of 3mm and the monofilament diameter of 5-10 mu m; the friction coefficient between the glass fiber and a mechanical component can be reduced in the process of drawing the glass fiber, the strength of the glass fiber can be improved, and the mechanical property of a composite material made of the glass fiber drawn by the impregnating compound is improved.

(2) The low-dielectric chopped glass fiber impregnating compound is used for the drawing process of glass fibers by adopting the bisphenol A type epoxy resin emulsion with the molecular weight of 4000-.

(3) The impregnating compound obtained by taking one of imidazoline cationic lubricant, imidazoline cationic lubricant and nonionic lubricant as lubricant A can be applied to the drawing process of glass fibers, so that the friction coefficient between the glass fibers and mechanical parts can be reduced, and the strength of the glass fibers can be improved by taking organosilicon lubricant as lubricant B to be applied to the drawing process of the glass fibers.

(4) The mass ratio of the high molecular weight bisphenol A epoxy resin emulsion to the polyurethane emulsion is most preferably 10:1, and the impregnating compound obtained by adopting the main film-forming agent with the mass ratio can enable the dispersibility of the glass fiber to be better and can better accord with the mechanical property of a chopped glass fiber product when being applied to the drawing process of the glass fiber.

Detailed Description

It should be noted that the following detailed description is exemplary and is intended to provide further explanation of the disclosure. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs.

It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments according to the present application. As used herein, the singular forms also include the plural forms unless the context clearly dictates otherwise, and further, it is understood that when the terms "comprises" and/or "comprising" are used in this specification, they specify the presence of the stated features, steps, operations, devices, components, and/or combinations thereof.

The technical solutions of the present invention will be described clearly and completely with reference to the following embodiments, and it should be understood that the described embodiments are some, but not all, embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Example 1

A low-dielectric chopped glass fiber impregnating compound comprises the following components in percentage by mass: 18% of main film-forming agent, 4% of auxiliary film-forming agent, 0.1% of lubricant A, 0.4% of organic silicon lubricant, 0.5% of coupling agent, 0.07% of pH regulator and the balance of deionized water.

Wherein: the main film-forming agent is a mixture obtained by mixing bisphenol A epoxy resin emulsion with the average molecular weight of 4500 and polyurethane emulsion with the average molecular weight of 25000 according to the mass ratio of 12:1, the auxiliary film-forming agent is bisphenol A epoxy resin emulsion with the average molecular weight of 1100, the lubricant A adopts imidazoline polyethyleneimine polyamide salt lubricant, the coupling agent adopts silane coupling agent KH570, and the pH regulator adopts glacial acetic acid.

A preparation method of a low-dielectric chopped glass fiber impregnating compound comprises the following steps:

(1) and (2) mixing a pH regulator and deionized water according to a mass ratio of 1:2, adding the coupling agent into a container with a stirring device, adding the coupling agent, stirring at the stirring speed of 60prm for 15min, and standing for 1h at the temperature of 10 ℃ to obtain the coupling agent diluent.

(2) Adding the organic silicon lubricant and deionized water into another container with a stirring device according to the mass ratio of 1:1.5, and stirring at the stirring speed of 60prm for 10min to obtain the organic silicon lubricant diluent.

(3) Adding the lubricant A and 50 ℃ deionized water into another container with a stirring device according to the mass ratio of 1:12, and stirring at the stirring speed of 60rpm for 5min to obtain the lubricant A diluent.

(4) Adding the main film forming agent, the auxiliary film forming agent and the deionized water into another container with a stirring device, wherein the mass ratio of the total mass of the main film forming agent and the auxiliary film forming agent to the deionized water is 1:1.1, stirring at the stirring speed of 60prm for 10min to obtain the film forming agent diluent.

(5) Adding deionized water accounting for 40% of the total mass of the impregnating compound into a preparation kettle, adding the coupling agent diluent obtained in the step (1) into the preparation kettle, stirring at the stirring speed of 60prm for 10 minutes, sequentially adding the diluents obtained in the steps (2), (3) and (4) into the preparation kettle, and finally adding deionized water until the solid content is 9%.

Example 2

A low-dielectric chopped glass fiber impregnating compound comprises the following components in percentage by mass: 20% of main film forming agent, 2% of auxiliary film forming agent, 0.05% of lubricant A, 0.6% of organic silicon lubricant, 0.4% of coupling agent, 0.05% of pH regulator and the balance of deionized water.

Wherein: the main film-forming agent is a mixture obtained by mixing bisphenol A epoxy resin emulsion with the average molecular weight of 5500 and polyurethane emulsion with the average molecular weight of 30000 according to the mass ratio of 10:1, the auxiliary film-forming agent is bisphenol A epoxy resin emulsion with the average molecular weight of 1300, the lubricant A is a compound of imidazoline cationic lubricant and nonionic lubricant, the mass ratio of the imidazole cationic lubricant to the nonionic lubricant is 1:2.1, the coupling agent is silane coupling agent 6032, and the pH regulator is citric acid.

A preparation method of a low-dielectric chopped glass fiber impregnating compound comprises the following steps:

(1) adding a pH regulator and deionized water into a container with a stirring device according to the mass ratio of 1:2.5, adding a coupling agent, stirring at the stirring speed of 80prm for 20min, and standing for 4h at the temperature of 4 ℃ to obtain a coupling agent diluent.

(2) Mixing an organic silicon lubricant and deionized water according to a mass ratio of 1:1.5 is added into another container with a stirring device, and stirring is carried out, wherein the stirring speed is 80prm, and the stirring time is 15 min. Obtaining the organic silicon lubricant diluent.

(3) Adding the lubricant A and deionized water at 55 ℃ into another container with a stirring device according to the mass ratio of 1:11, and stirring at the stirring speed of 80rpm for 10min to obtain the lubricant A diluent.

(4) Adding the main film forming agent, the auxiliary film forming agent and the deionized water into another container with a stirring device, wherein the mass ratio of the total mass of the main film forming agent and the auxiliary film forming agent to the deionized water is 1:1, stirring at the stirring speed of 60prm for 10min to obtain the film forming agent diluent.

(5) Adding deionized water accounting for 40% of the total mass of the impregnating compound into a preparation kettle, adding the coupling agent diluent obtained in the step (1) into the preparation kettle, stirring at the stirring speed of 80prm for 15 minutes, sequentially adding the diluents obtained in the steps (2), (3) and (4) into the preparation kettle, and finally adding deionized water until the solid content is 11%.

Example 3

A low-dielectric chopped glass fiber impregnating compound comprises the following components in percentage by mass: 21% of main film-forming agent, 1% of auxiliary film-forming agent, 0.05% of lubricant A, 0.5% of organic silicon lubricant, 0.3% of coupling agent, 0.1% of pH regulator and the balance of deionized water.

Wherein: the film forming agent is a mixture obtained by mixing bisphenol A epoxy resin emulsion with the average molecular weight of 5000 and polyurethane emulsion with the average molecular weight of 35000 according to the mass ratio of 11:1, the auxiliary film forming agent is bisphenol A epoxy resin emulsion with the average molecular weight of 1250, the lubricant A adopts imidazoline polyethyleneimine polyamide salt lubricant, the coupling agent adopts silane coupling agent 6032, and the pH regulator adopts citric acid.

A preparation method of a low-dielectric chopped glass fiber impregnating compound comprises the following steps:

(1) and (2) mixing a pH regulator and deionized water according to a mass ratio of 1:3, adding the coupling agent into a container with a stirring device, adding the coupling agent, stirring at the stirring speed of 70prm for 17min, and standing at the temperature of 0 ℃ for 3.5h to obtain the coupling agent diluent.

(2) Mixing an organic silicon lubricant and deionized water according to a mass ratio of 1:2, adding the mixture into another container with a stirring device, and stirring at the stirring speed of 70prm for 15min to obtain the organosilicon lubricant diluent.

(3) Adding the lubricant A and deionized water at 60 ℃ into another container with a stirring device according to the mass ratio of 1:12, and stirring at the stirring speed of 80rpm for 10min to obtain the lubricant A diluent.

(4) Adding the main film forming agent, the auxiliary film forming agent and the deionized water into another container with a stirring device, wherein the mass ratio of the total mass of the main film forming agent and the auxiliary film forming agent to the deionized water is 1:1.2, stirring at the stirring speed of 70prm for 10min to obtain the film forming agent diluent.

(5) Adding deionized water accounting for 50% of the total mass of the impregnating compound into a preparation kettle, adding the coupling agent diluent obtained in the step (1) into the preparation kettle, stirring at the stirring speed of 80prm for 15 minutes, sequentially adding the diluents obtained in the steps (2), (3) and (4) into the preparation kettle, and finally adding deionized water until the solid content is 13%.

Comparative example 1

A low dielectric chopped glass fiber impregnating compound, the adopted components and the preparation method are basically consistent with those of the embodiment 2, and the only difference is that: the polyurethane emulsion is not added into the main film forming agent.

Comparative example 2

A low dielectric chopped glass fiber impregnating compound, the adopted components and the preparation method are basically consistent with those of the embodiment 2, and the only difference is that: the average molecular weight of the bisphenol A epoxy resin emulsion in the main film-forming agent is 450, and other components and the preparation process are the same as those in the example 1.

The impregnating compounds prepared in examples 1-3 and comparative examples 1-2 were used to produce low dielectric chopped glass fibers according to the conventional low dielectric chopped glass fiber production process in the art, and the produced low dielectric chopped glass fibers were subjected to performance tests:

(1) fabric stiffness: and (3) testing the glass fiber by using a fabric stiffness tester to obtain a bending length value, wherein the bending length value is shown in table 1, and the larger the bending length value is, the higher the stiffness of the glass fiber is.

(2) The dispersibility, the agglomeration phenomenon will occur when the fiber monofilament dispersibility is poor in the preparation process of the glass fiber, the dispersibility among the glass fibers is good, the non-uniform dispersion among the glass fibers is poor, and the experimental results are shown in table 1.

(3) And (2) antistatic property, namely measuring the antistatic property of the glass fiber, when the glass fiber is chopped, judging whether the antistatic property is good or not according to whether the glass fiber is adsorbed on equipment or accumulated when the glass fiber is chopped or not, wherein the antistatic property is good when the glass fiber is not adsorbed on the equipment, and the antistatic property is poor when the glass fiber is adsorbed on the equipment or accumulated, and the experimental result is shown in table 1.

(4) Tensile stress at break: the tensile stress at break of the composite materials made of the glass fibers drawn from the impregnating agents obtained in examples 1 to 3 of the present invention and comparative examples 1 to 2 was measured, and the results of the tests are shown in Table 1.

The sizing agents produced in examples 1 to 3 and comparative examples 1 to 2 were used for the preparation of glass fibers, the preparation process was carried out by the prior art, and the prepared glass fibers were tested for stiffness, dispersibility and antistatic property, and the test results are as follows:

TABLE 1

In Table 1, "O" represents that the yarn used has good bundling property, and "X" represents that the yarn has poor bundling property.

The sizing agents prepared in comparative examples 1 and 2 were difficult to prepare glass fibers having a chopped length of 3mm because the glass fibers had poor bundling properties and were easily scattered when chopped to a length of 3 mm.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit the same; while the invention has been described in detail and with reference to the foregoing embodiments, it will be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; and the modifications or the substitutions do not make the essence of the corresponding technical solutions depart from the scope of the technical solutions of the embodiments of the present invention.