Glass fiber sizing compositions and glass fiber sizing, glass fiber products and applications

Abstract

The application provides a glass fiber sizing agent composition and glass fiber sizing agent, glass fiber product and application. The glass fiber sizing agent composition comprises effective components and water, and the effective components comprise, in terms of mass percentage, 5.0-15.0% of a silane coupling agent, 55.0-80.0% of a film forming agent, 4.0-12.0% of an antioxidant and 8.0-30.0% of an accelerator; wherein the solid content of the sizing agent composition is 6.0-15.0%. Through the synergistic cooperation of the above components, the glass fiber chopped strand produced by using the above glass fiber sizing agent composition has good bunching property, less hairiness in the production and use processes, good compatibility with polybutylene terephthalate, significantly enhanced mechanical properties of the polybutylene terephthalate post-composite material, and significantly improved heat and oxygen aging resistance.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of catalyst, in particular to a glass fiber sizing composition, glass fiber sizing agent, glass fiber product and application. BACKGROUND

[0002] Polybutylene terephthalate (PBT) has excellent mechanical properties, electrical properties and good dimensional stability. After being reinforced by glass fiber, the mechanical properties, thermal properties and dimensional stability are further improved, and the reinforced PBT still retains good electrical properties, so it is widely used in electronic appliances, household appliances, automobiles, machinery and other fields. Although the existing PBT glass fiber composite material has good mechanical properties and heat resistance, it will be attacked by heat and oxygen during long-term use, resulting in performance degradation such as yellowing and whitening, and its performance will gradually decrease. Thermal-oxidative aging is one of the important factors affecting the performance of PBT glass fiber composite material, which can cause deterioration of the mechanical properties, thermal properties and appearance quality of the material.

[0003] Therefore, it is crucial to develop a sizing agent that can effectively resist thermal-oxidative aging to prolong the service life of PBT glass fiber composite material. SUMMARY

[0004] The main purpose of the present application is to provide a glass fiber sizing composition, glass fiber sizing agent, glass fiber product and application to solve the problem of thermal-oxidative aging of PBT glass fiber composite material in the prior art.

[0005] In order to achieve the above-mentioned purpose, according to one aspect of the present application, a glass fiber sizing composition is provided, which comprises an effective component and water, and the effective component comprises, in terms of mass percentage, 5.0-15.0% silane coupling agent, 55.0-80.0% film forming agent, 4.0-12.0% antioxidant and 8.0-30.0% accelerator; wherein the solid content of the sizing composition is 6.0-15.0%; the silane coupling agent is an epoxy silane coupling agent, the film forming agent is an epoxy emulsion and / or a polyurethane emulsion, the antioxidant is a hindered phenolic antioxidant, and the accelerator is an aromatic amine accelerator.

[0006] Further, the above-mentioned effective component comprises, in terms of mass percentage, 6.0-13.0% silane coupling agent, 60.0-70.0% film forming agent, 5.0-10.0% antioxidant and 12.0-19.0% accelerator; wherein the solid content of the sizing composition is 7.0-14.0%; preferably, the effective component comprises 7.5-12.0% silane coupling agent, 65.0-70.0% film forming agent, 6.0-10.0% antioxidant and 14.0-19.0% accelerator.

[0007] Further, the ratio of the dry mass of the epoxy emulsion to the dry mass of the polyurethane emulsion is 1:1 to 6:1, preferably 1:1 to 3:1.

[0008] Further, the epoxy silane coupling agent is selected from any one or more of 2-(3,4-epoxycyclohexyl)ethyl trimethoxysilane, γ-glycidoxypropyl trimethoxysilane, 3-(2,3-epoxypropoxy)propyl methyldiethoxysilane, and γ-glycidoxypropyl triethoxysilane.

[0009] Further, the epoxy emulsion is a phenol novolac-modified epoxy emulsion and / or a bismaleimide-modified epoxy emulsion, and the polyurethane emulsion is an aliphatic polyurethane emulsion and / or a polyolefin-based polyurethane emulsion.

[0010] Further, the hindered phenol-based antioxidant is selected from any one or more of an alkyl monophenol compound, an alkyl polyphenol compound, and a thio polyphenol compound.

[0011] Further, the aromatic amine-based accelerator is selected from any one or more of diaminodiphenylmethane, diaminodiphenylsulfone, and 3,3'-diethyl-4,4'-diaminodiphenylmethane.

[0012] According to another aspect of the present application, there is provided a glass fiber sizing agent obtained by mixing the glass fiber sizing agent composition described above.

[0013] According to still another aspect of the present application, there is provided a glass fiber product coated with the glass fiber sizing agent described above.

[0014] According to still another aspect of the present application, there is provided a use of the glass fiber product described above in a reinforced polybutylene terephthalate resin composite.

[0015] The film forming agent of the present application is a combination of epoxy emulsion and / or polyurethane emulsion. The epoxy resin has good compatibility with polybutylene terephthalate (PBT resin), so that the final product has excellent mechanical properties and gives the composite material more excellent heat and oxygen aging resistance. The selected epoxy emulsion improves the combination of glass fiber and PBT resin and gives the composite material better heat and oxygen aging stability. At the same time, the selected polyurethane emulsion has excellent film forming properties, and the glass fiber coated with polyurethane has better processability, which helps to improve the heat and oxygen aging resistance of the composite material. At the same time, the film forming agent used in the present application needs to be controlled within a certain range. If the amount of film forming agent is too much, it will cause the glass fiber to be too strong in bundling and difficult to disperse, reducing the mechanical properties of the composite material. If the amount of film forming agent is too small, the wear resistance of the glass fiber surface will be poor, the hairiness will increase, affecting the production smoothness and easily leading to floating fiber. Therefore, the amount of film forming agent is preferably controlled within the above range. The antioxidant used in the present application is a hindered phenolic antioxidant. Due to its unique structure, it is different from ordinary antioxidants. Hindered phenolic antioxidants are a class of compounds with substituent groups on one side or both sides of the benzene ring -OH. Most of the time, its structure includes two tert-butyl groups. Due to the limitation of the hydroxyl group by the spatial barrier, the hydrogen atom (H) is easily detached from the original molecular structure, thereby achieving the role of giving protons and combining with peroxide radicals (ROO-), alkyl radicals, hydroxyl radicals, etc. to cause the loss of its original activity, resulting in the termination of the oxygen aging reaction. The amount of antioxidant is an important factor affecting the heat and oxygen aging resistance of glass fiber in PBT resin. If the amount of antioxidant is too much, it will cause the product to have poor bundling, resulting in more hairiness of glass fiber during the extrusion process and performance degradation. If the amount of antioxidant is too small, it will not improve the heat and oxygen aging resistance. Therefore, the amount of antioxidant is controlled within the above range. The accelerator selected is an aromatic amine accelerator. This type of accelerator has an oil-stable benzene ring structure in its molecular structure. Due to the presence of the benzene ring, the accelerator itself has high heat resistance. At the same time, the amine can also promote the curing and crosslinking reaction of the epoxy resin. At the same time, the amount of accelerator must also be controlled within a certain range. With the increase of the amount of curing agent, the tensile and bending properties of the composite material will first increase and then decrease. Therefore, the amount of accelerator is controlled within the above range. The silane coupling agent in the present application is an epoxy silane coupling agent, which can cooperate with the above types of film forming agent, antioxidant and accelerator to effectively improve the compatibility of glass fiber and PBT resin. At the same time, the amount of silane coupling agent needs to be controlled within a suitable range. If the amount of silane coupling agent is too much, it will cause the product to be yellowish in color and the glass fiber to be poor in dispersibility in the resin, which will affect the final heat and oxygen aging resistance. If the amount of silane coupling agent is too small, the mechanical properties of the composite material will not meet the design requirements. Therefore, the amount of silane coupling agent is preferably controlled within the above range.The synergistic cooperation of the above components makes the glass fiber short-cut roving produced by the above glass fiber sizing composition have good bundling property, less hairiness in the production and use process, good compatibility with PBT resin, significantly enhanced mechanical properties of the PBT resin after composite material, and significantly improved heat-oxidative aging resistance. DETAILED DESCRIPTION

[0016] It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict. The present application will be described in detail below with reference to the embodiments.

[0017] As analyzed in the background art of the present application, the PBT glass fiber composite material in the prior art is prone to heat-oxidative aging. In order to solve the above problems, the present application provides a glass fiber sizing composition, a glass fiber sizing agent, a glass fiber product and an application.

[0018] In a typical embodiment of the present application, a glass fiber sizing composition is provided, which comprises effective components and water, and the effective components comprise, in terms of mass percentage, 5.0-15.0% of a silane coupling agent, 55.0-80.0% of a film-forming agent, 4.0-12.0% of an antioxidant and 8.0-30.0% of a promoter; wherein the solid content of the sizing composition is 6.0-15.0%; the silane coupling agent is an epoxy silane coupling agent, the film-forming agent is an epoxy emulsion and / or a polyurethane emulsion, the antioxidant is a hindered phenol antioxidant, and the promoter is an aromatic amine promoter.

[0019] The film forming agent of the present application is a combination of epoxy emulsion and / or polyurethane emulsion. The epoxy resin has good compatibility with polybutylene terephthalate (PBT resin), so that the final product has excellent mechanical properties, and gives the composite material more excellent heat-oxidative aging resistance. The selected epoxy emulsion improves the combination of glass fiber and PBT resin, and gives the composite material better heat-oxidative aging stability, at the same time, the selected polyurethane emulsion has excellent film forming performance, the glass fiber coated with polyurethane has better processability, which helps to improve the heat-oxidative aging resistance of the composite material. At the same time, the film forming agent used in the present application needs to be controlled within a certain range, if the amount of film forming agent is too much, it will lead to the glass fiber bundle too strong and not easy to disperse, reducing the mechanical properties of the composite material; if the amount of film forming agent is too small, it will lead to the wear resistance of the glass fiber surface to be poor, the hairiness to increase, affecting the production smoothness and easily leading to floating fiber. Therefore, the amount of film forming agent is preferably controlled within the above range. The antioxidant used in the present application is a hindered phenolic antioxidant, which is different from ordinary antioxidants due to its unique structure. Hindered phenolic antioxidants are a class of compounds with substituent groups on one side or both sides of the benzene ring -OH. Most of the time, its structure includes two tert-butyl groups. Due to the limitation of the hydroxyl group by the space barrier, the hydrogen atom (H) is easily detached from the original molecular structure, thereby achieving the role of giving proton and combining with peroxide free radicals (ROO-), alkyl free radicals, hydroxyl free radicals, etc., resulting in the loss of original activity, causing the termination of oxygen aging reaction. The amount of antioxidant is an important factor affecting the heat-oxidative aging resistance of glass fiber in PBT resin, if the amount of antioxidant is too much, it will cause the product to have poor bundle, leading to more hairiness of glass fiber in the extrusion process, and the performance decreases; if the amount of antioxidant is too small, it will not have the effect of improving the heat-oxidative aging resistance. Therefore, the amount of antioxidant is controlled within the above range. The accelerator selected is an aromatic amine accelerator, which contains an oil-stable benzene ring structure in its molecular structure. Due to the presence of benzene ring, the accelerator itself has high heat resistance. At the same time, the amine can also promote the curing crosslinking reaction of epoxy resin. At the same time, the amount of accelerator must also be controlled within a certain range, with the increase of the amount of curing agent, the tensile and bending properties of the composite material will first increase and then decrease. Therefore, the amount of accelerator is controlled within the above range. The silane coupling agent in the present application is an epoxy silane coupling agent, which can cooperate with the above types of film forming agent, antioxidant and accelerator, effectively improving the compatibility of glass fiber and PBT resin. At the same time, the amount of silane coupling agent needs to be controlled within a suitable range, if the amount of silane coupling agent is too much, it will cause the product to be yellowish, the dispersibility of glass fiber in the resin will also be poor, which will affect the final heat-oxidative aging resistance; if the amount of silane coupling agent is too small, it will lead to the mechanical properties of the composite material cannot meet the design requirements. Therefore, the amount of silane coupling agent is preferably controlled within the above range.The synergistic cooperation of the above components makes the glass fiber short-cut roving produced by the above glass fiber sizing composition have good bundling, less hairiness in production and use, good compatibility with PBT resin, significantly enhanced mechanical properties of PBT resin after composite material, and significantly improved heat-oxidative aging resistance.

[0020] In addition, the solid mass of each effective component in the present application refers to the mass of the non-aqueous component of the corresponding effective component. Water in the present application is the dispersion phase of each effective component in the glass fiber sizing composition, wherein the water is preferably deionized water.

[0021] In order to further improve the synergistic effect of each component in the glass fiber sizing composition and make each component play a better performance, in an embodiment of the present application, the effective components preferably include 6.0% to 13.0% of silane coupling agent, 60.0% to 70.0% of film forming agent, 5.0% to 10.0% of antioxidant and 12.0% to 19.0% of accelerator, wherein the solid content of the sizing composition is 7.0% to 14.0%; further preferably, the effective components include 7.5% to 12.0% of silane coupling agent, 65.0% to 70.0% of film forming agent, 6.0% to 10.0% of antioxidant and 14.0% to 19.0% of accelerator.

[0022] In an embodiment of the present application, the ratio of the dry mass of the above-mentioned epoxy emulsion to the dry mass of the polyurethane emulsion is 1:1 to 6:1, preferably 1:1 to 3:1.

[0023] The film forming agent is one of the most important components in the glass fiber sizing composition, which determines the performance of glass fiber production, processing and PBT resin composite reinforced by it. The use of a mixture of epoxy emulsion and polyurethane emulsion is beneficial to the mechanical properties and use performance of glass fiber. The higher the proportion of epoxy emulsion, the better the compatibility with PBT resin; on the contrary, the polyurethane emulsion is mainly used, the bundling is more excellent, the hairiness is less and the use performance is better. Therefore, it is preferred to control the ratio of the dry mass of the above-mentioned epoxy emulsion to the dry mass of the polyurethane emulsion within the above range, which is more helpful to the compatibility of the performance of the epoxy emulsion and the polyurethane emulsion, so that the comprehensive performance of the glass fiber is more excellent. Depending on the needs, for example, the ratio of the dry mass of the epoxy emulsion to the dry mass of the polyurethane emulsion is 1:1, 2:1, 3:1, 4:1, 5:1 or 6:1.

[0024] In an embodiment of the present application, the above-mentioned epoxy silane coupling agent is selected from any one or more of 2-(3,4-epoxycyclohexyl)ethyl trimethoxysilane, γ-glycidoxypropyl trimethoxysilane, 3-(2,3-epoxypropoxy)propyl methyldiethoxysilane and γ-glycidoxypropyl triethoxysilane type silane coupling agent.

[0025] The silane coupling agent in the present application can have coupling effect between the glass fiber and the PBT resin. On the one hand, it can repair the micro-cracks of the glass fiber in the production process. On the other hand, it also affects the compatibility and interface bonding of the glass fiber and the PBT resin, thereby affecting the mechanical properties of the composite material. Specifically, the preferred epoxy silane coupling agent of the above type has excellent high-temperature resistance, better compatibility with the PBT resin, and relatively more moderate reaction speed, thereby more helping to improve the interface bonding between the glass fiber and the PBT resin.

[0026] In addition, the present application selects the epoxy silane coupling agent without the aid of other coupling agents. From the experimental results, the single epoxy coupling agent has the best heat-oxidative aging effect on the composite material. The addition of amino or other types of silane coupling agents will reduce the final heat-oxidative aging performance. It is speculated that the possible reason is that after the addition of amino silane, the bonding between the glass filaments is strengthened, which affects the dispersion performance of the glass fiber to a certain extent, and the uniformity of the resin is relatively poor. Other types of silane coupling agents, such as A174, have poor compatibility with PBT resin, which affects the bonding of glass fiber and resin.

[0027] In an embodiment of the present application, the above-mentioned epoxy emulsion is a phenolic modified epoxy emulsion and / or a bismaleimide modified epoxy emulsion, and the polyurethane emulsion is an aliphatic polyurethane emulsion and / or a polyolefin type polyurethane emulsion.

[0028] The film forming agent can protect the glass fiber from being abraded during the drawing process, maintain the bundling of the yarn, improve the compatibility of the glass fiber and the PBT resin when reinforcing the resin, and the film forming agent modified in particular can also endow the final composite material with more functional characteristics. Therefore, selecting a suitable film forming agent can not only ensure the bundling of the yarn and the smoothness in subsequent use, but also ensure that the glass fiber and the matrix resin are uniformly mixed and the interface bonding is sufficient and complete, thereby improving the mechanical properties of the composite material and the product, and endowing the composite material with more excellent heat-oxidative aging performance. The present application preferably uses a phenolic modified epoxy emulsion and / or a bismaleimide modified epoxy emulsion. The chemical name of the phenolic epoxy resin (EPN) is linear phenolic polyglycidyl ether, which is a light brown yellow viscous liquid and a heat-resistant epoxy resin. Bismaleimide (BMI) is another type of resin derived from a polyimide resin system, which is a bifunctional compound with maleimide (MI) as the active end group. It has similar flowability and moldability to epoxy resin, and can be processed and molded in a similar way to epoxy resin. The preferred above-mentioned epoxy emulsion helps to improve the heat resistance of the epoxy resin, thereby improving the heat-oxidative aging performance of the glass fiber.

[0029] In an embodiment of the present application, the hindered phenolic antioxidant is selected from any one or more of an alkyl monophenol compound, an alkyl polyphenol compound, and a thio polyphenol compound.

[0030] The use of appropriate antioxidants can provide more excellent heat resistance for the glass fiber, and improve the anti-aging performance of the sizing agent, improve the color of the composite material product, and improve the anti-aging performance of the composite material. The use of the above types of antioxidants in the present application helps to terminate the aging reaction more timely and accurately.

[0031] In an embodiment of the present application, the aromatic amine promoter is selected from any one or more of diaminodiphenylmethane, diaminodiphenyl sulfone, and 3,3'-diethyl-4,4'-diaminodiphenyl methane.

[0032] The use of the promoter in the present application improves the reaction degree of the epoxy resin in the sizing agent, improves the crosslinking degree after reaction, and improves the interfacial bonding of the glass fiber and the PBT resin. The aromatic amine promoter of the above type has higher heat resistance, and is beneficial to further promote the curing and crosslinking reaction of the epoxy resin.

[0033] In another typical embodiment of the present application, a glass fiber sizing agent is provided, which is obtained by mixing the glass fiber sizing agent composition described above.

[0034] The glass fiber sizing agent in the present application, which is obtained by mixing the glass fiber sizing agent composition described above, can significantly enhance the mechanical properties of the PBT resin after the composite material, and the heat and oxygen aging resistance is significantly improved.

[0035] In some optional embodiments, a preparation method of the aforementioned glass fiber sizing agent is provided, comprising the following steps:

[0036] S1: Hydrolysis of silane coupling agent: the silane coupling agent is added to water, and the silane coupling agent is hydrolyzed, and stirred until the solution is clear, to obtain a silane coupling agent solution;

[0037] S2: Dilution of film forming agent, antioxidant and promoter: the film forming agent, antioxidant and promoter are respectively diluted with water;

[0038] S3: The diluted film forming agent, antioxidant and promoter are added to the silane coupling agent solution, and the remaining water is added, and stirred uniformly to obtain the glass fiber sizing agent.

[0039] In some alternative embodiments, step S1 comprises adding water in an amount of 20-40 times the weight of the silane coupling agent in the first container, adding the silane coupling agent into the first container, hydrolyzing the silane coupling agent, stirring while adding, and stirring until the solution is clear and free of oil droplets to obtain a silane coupling agent solution.

[0040] In some alternative embodiments, step S2 comprises adding water in an amount of 1-2 times the weight of the film-forming agent at room temperature in the second container, then slowly adding the film-forming agent, stirring and dissolving to obtain a water-diluted film-forming agent.

[0041] In the third container, water in an amount of 1-2 times the weight of the antioxidant at room temperature is added, then the antioxidant is slowly added, stirred and dissolved to obtain a water-diluted antioxidant.

[0042] In the fourth container, water in an amount of 1-2 times the weight of the accelerator at room temperature is added, then the accelerator is slowly added, stirred and dissolved to obtain a water-diluted accelerator.

[0043] It should be noted that the terms "1S" and "2S" in this paper are only used to more clearly explain the technical solutions of the present application, and are not a limitation of the present application; the order of steps 1S and 2S in the preparation process can be adjusted according to actual conditions. Moreover, the water-diluted film-forming agent, antioxidant and accelerator can also be adjusted according to actual needs, which will not be described here.

[0044] In another typical embodiment of the present application, a glass fiber product coated with the above-mentioned glass fiber sizing agent is provided.

[0045] The glass fiber product coated with the above-mentioned glass fiber sizing agent has excellent mechanical properties and heat-oxidation aging resistance.

[0046] In some alternative embodiments, the chopped length of the glass fiber product is 2-9 mm, preferably 2.5-7.5 mm, and more preferably 3-6 mm.

[0047] In another typical embodiment of the present application, the use of the above-mentioned glass fiber product in reinforcing polybutylene terephthalate resin composites is provided.

[0048] The above-mentioned glass fiber product has great improvement effect and economic value in the application of reinforcing polybutylene terephthalate resin composites.

[0049] The beneficial effects of the present application will be further illustrated in the following examples.

[0050] In order to more clearly explain the technical solutions of the present application, the following lists partial specific examples (Examples 1-18) of the glass fiber sizing agent composition of the present application, wherein the specific formulations of the glass fiber sizing agent composition of Examples 1-18 of the present application are shown in Table 1, and in Table 1, the amount of each effective component is the percentage of the solid mass of the corresponding effective component to the total solid mass of the sizing agent.

[0051] It should be noted that the specific types and amounts of each component selected in Table 1 and the combination thereof do not constitute a limitation on the scope of protection of the present application.

[0052] Formulation of the sizing agent composition of Examples 1-18 in Table 1

[0053]

[0054]

[0055] Formulation of the sizing agent composition of Examples 1-18 in Table 1

[0056]

[0057]

[0058] Formulation of the sizing agent composition of Examples 1-18 in Table 1

[0059]

[0060]

[0061] The preparation method of the glass fiber sizing agent of Examples 1-18 specifically includes the following steps:

[0062] Hydrolysis of the silane coupling agent: the silane coupling agent is added to water to hydrolyze the silane coupling agent, and stirring is performed until the solution is clear to obtain a silane coupling agent solution;

[0063] Dilution of the film forming agent, antioxidant and accelerator: the film forming agent, antioxidant and accelerator are respectively diluted with water;

[0064] The diluted film forming agent, antioxidant and accelerator are added to the silane coupling agent solution, the remaining amount of water is added, and stirring is performed until uniform to obtain the glass fiber sizing agent.

[0065] In addition, in order to further illustrate the beneficial effects of the present application, the following sizing agent formulations (Comparative Examples 1-3) are selected as comparative examples, wherein Comparative Example 3 is a commonly used sizing agent for glass fibers used to reinforce polybutylene terephthalate resin, which facilitates comparison with the technical solutions of the present application.

[0066] Comparative Example 1

[0067] The sizing agent contains effective components and water, and the solid content is 9.0%, the solid mass percentage of each effective component in the total mass of the sizing agent is shown as follows:

[0068] Coupling agent (amino silane coupling agent): 15%;

[0069] Film forming agent (bisphenol A epoxy resin and polyether polyurethane): 75%;

[0070] Lubricant (silicone oil lubricant): 10%.

[0071] Comparative Example 2

[0072] The sizing agent contains effective components and water, and the solid content is 8.5%, the solid mass percentage of each effective component in the total mass of the sizing agent is shown as follows:

[0073] Coupling agent (amino silane coupling agent and epoxy silane coupling agent): 10%;

[0074] Film forming agent (alicyclic epoxy emulsion): 80%;

[0075] Lubricant (polyether lubricant): 10%.

[0076] Comparative Example 3

[0077] The sizing agent contains effective components and water, and the solid content is 8.0%, the solid mass percentage of each effective component in the total mass of the sizing agent is shown as follows:

[0078] Coupling agent (amino silane coupling agent): 10%;

[0079] Film forming agent (bisphenol A type epoxy and polyurethane-urea emulsion mixture): 76%;

[0080] Antioxidant (phosphite antioxidant): 14%.

[0081] The preparation method of the glass fiber sizing agent of Comparative Examples 1-3 specifically includes the following steps:

[0082] Hydrolysis of the coupling agent: the coupling agent is added to water, and the coupling agent is hydrolyzed, and stirred until the solution is clear to obtain a coupling agent solution;

[0083] Dilution of the film forming agent, antioxidant and accelerator: the film forming agent, antioxidant and accelerator are respectively diluted with water;

[0084] The diluted film forming agent, antioxidant and accelerator are added to the coupling agent solution, and the remaining water is added, and stirred uniformly to obtain the glass fiber sizing agent.

[0085] Performance detection:

[0086] The performance of examples 1-18 and comparative examples 1-3 was tested by comparison, and the test method was as follows:

[0087] The sizing agent of examples 1-18 and comparative examples 1-3 was respectively coated for the production of glass fiber, and the corresponding glass fiber was baked and cut, and finally the cut fiber product was prepared, and the cut length was 3mm.

[0088] Then the corresponding cut glass fiber was melt-mixed with polybutylene terephthalate resin, extruded and granulated, and finally the glass fiber reinforced polybutylene terephthalate resin composite material (glass fiber content was 30%) was prepared, and part of the composite material was placed in a constant temperature oven, and after 48h of heat preservation at 205℃, the performance was retested. The performance test results are shown in Table 2.

[0089] Tensile strength: ISO 527-1-2012.

[0090] Bending strength: ISO 178-2010.

[0091] Unnotched impact strength: ISO 179-1-2010.

[0092] Notched impact strength: ISO 179-1-2010.

[0093] Table 2 Performance test results of examples and comparative examples

[0094]

[0095]

[0096] Table 2 (continued) Performance test results of examples and comparative examples

[0097]

[0098] Table 2 (continued) Performance test results of examples and comparative examples

[0099]

[0100] From the above description, it can be seen that the above-mentioned examples of the present application achieve the following technical effects:

[0101] The film forming agent of the present application is a combination of epoxy emulsion and / or polyurethane emulsion. The epoxy resin has good compatibility with polybutylene terephthalate (PBT resin), so that the final product has excellent mechanical properties, and gives the composite material more excellent heat-oxidative aging resistance. The selected epoxy emulsion improves the combination of glass fiber and PBT resin, and gives the composite material better heat-oxidative aging stability, at the same time, the selected polyurethane emulsion has excellent film forming performance, the glass fiber coated with polyurethane has better processability, which helps to improve the heat-oxidative aging resistance of the composite material. At the same time, the film forming agent used in the present application needs to be controlled within a certain range, if the amount of film forming agent is too much, it will lead to the glass fiber bundle too strong and not easy to disperse, reducing the mechanical properties of the composite material; if the amount of film forming agent is too small, it will lead to the wear resistance of the glass fiber surface to be poor, the hairiness to increase, affecting the production smoothness and easily leading to floating fiber. Therefore, the amount of film forming agent is preferably controlled within the above range. The antioxidant used in the present application is a hindered phenolic antioxidant, which is different from ordinary antioxidants due to its unique structure. Hindered phenolic antioxidants are a class of compounds with substituent groups on one side or both sides of the benzene ring -OH. Most of the time, its structure includes two tert-butyl groups. Due to the limitation of the hydroxyl group by the space barrier, the hydrogen atom (H) is easily detached from the original molecular structure, thereby achieving the role of giving proton and combining with peroxide free radicals (ROO-), alkyl free radicals, hydroxyl free radicals, etc., resulting in the loss of original activity, causing the termination of oxygen aging reaction. The amount of antioxidant is an important factor affecting the heat-oxidative aging resistance of glass fiber in PBT resin, if the amount of antioxidant is too much, it will cause the product to have poor bundle, leading to more hairiness of glass fiber in the extrusion process, and the performance decreases; if the amount of antioxidant is too small, it will not have the effect of improving the heat-oxidative aging resistance. Therefore, the amount of antioxidant is controlled within the above range. The accelerator selected is an aromatic amine accelerator, which contains an oil-stable benzene ring structure in its molecular structure. Due to the presence of benzene ring, the accelerator itself has high heat resistance. At the same time, the amine can also promote the curing crosslinking reaction of epoxy resin. At the same time, the amount of accelerator must also be controlled within a certain range, with the increase of the amount of curing agent, the tensile and bending properties of the composite material will first increase and then decrease. Therefore, the amount of accelerator is controlled within the above range. The silane coupling agent in the present application is an epoxy silane coupling agent, which can cooperate with the above types of film forming agent, antioxidant and accelerator, effectively improving the compatibility of glass fiber and PBT resin. At the same time, the amount of silane coupling agent needs to be controlled within a suitable range, if the amount of silane coupling agent is too much, it will cause the product to be yellowish, the dispersibility of glass fiber in the resin will also be poor, which will affect the final heat-oxidative aging resistance; if the amount of silane coupling agent is too small, it will lead to the mechanical properties of the composite material cannot meet the design requirements. Therefore, the amount of silane coupling agent is preferably controlled within the above range.The synergistic cooperation of the above components makes the glass fiber short-cut roving produced by the above glass fiber sizing agent composition have good bundling, less hairiness in the production and use process, good compatibility with PBT resin, significantly enhanced mechanical properties of PBT resin after composite material, and significantly improved heat and oxygen aging resistance.

[0102] The above is only an embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A glass fiber sizing composition comprising an effective component and water, characterized in that, The effective component comprises, in mass percentage: 5.0%~15.0% silane coupling agent; 55.0%~80.0% film forming agent; 4.0%~12.0% antioxidant; 8.0%~30.0% accelerator; The solid content of the infiltrant composition is 6.0%~15.0%; the silane coupling agent is an epoxy silane coupling agent, the film forming agent is an epoxy emulsion and / or a polyurethane emulsion, the antioxidant is a hindered phenol antioxidant, and the accelerator is an aromatic amine accelerator. The aromatic amine accelerator is selected from any one or more of diaminodiphenylmethane, diaminodiphenyl sulfone and 3,3'-diethyl-4,4'-diaminodiphenyl methane.

2. The glass fiber sizing composition of claim 1, wherein, The effective component comprises, in mass percentage: 6.0%~13.0% silane coupling agent; 60.0%~70.0% film forming agent; 5.0%~10.0% antioxidant; 12.0%~19.0% accelerator; The solid content of the infiltrant composition is 7.0%~14.0%.

3. The glass fiber sizing composition of claim 2, wherein, The effective component comprises, in mass percentage: 7.5%~12.0% silane coupling agent; 65.0%~70.0% film forming agent; 6.0%~10.0% antioxidant; 14.0%~19.0% accelerator.

4. The glass fiber sizing composition according to any one of claims 1 to 3, characterized in that, The ratio of the dry mass of the epoxy emulsion to the dry mass of the polyurethane emulsion is 1:1~6:

1.

5. The glass fiber sizing composition according to claim 4, wherein, The ratio of the dry mass of the epoxy emulsion to the dry mass of the polyurethane emulsion is 1:1~3:

1.

6. The glass fiber sizing composition according to any one of claims 1 to 3, characterized in that, The epoxy silane coupling agent is selected from any one or more of 2-(3,4-epoxycyclohexyl)ethyl trimethoxysilane, γ-glycidoxypropyl trimethoxysilane, 3-(2,3-epoxypropoxy)propyl methyldiethoxysilane and γ-glycidoxypropyl triethoxysilane type silane coupling agent.

7. The glass fiber sizing composition according to any one of claims 1 to 3, characterized in that, The epoxy emulsion is a phenolic modified epoxy emulsion and / or a bismaleimide modified epoxy emulsion, and the polyurethane emulsion is an aliphatic polyurethane emulsion and / or a polyolefin type polyurethane emulsion.

8. The glass fiber sizing composition according to any one of claims 1 to 3, characterized in that, The hindered phenol antioxidant is selected from any one or more of alkyl monophenol compound, alkyl polyphenol compound and thio polyphenol compound.

9. A glass fiber sizing obtained by mixing a glass fiber sizing composition, characterized in that, The glass fiber infiltrant composition is the glass fiber infiltrant composition according to any one of claims 1 to 8.

10. A glass fiber product produced by coating with the glass fiber infiltrant according to claim 9.

11. Use of the glass fiber product according to claim 10 in reinforcing polybutylene terephthalate resin composites.

Images