JPS6046951A - Glass fiber for reinforcing plastic - Google Patents

Abstract

PURPOSE:The titled glass fiber providing a molded article with improved water resistance and mechanical strength, obtained by treating the surface of glass fiber with a specific maleic anhydride copolymer and a silane coupling agent. CONSTITUTION:100Pts.wt. copolymer of 30-70mol% maleic anhydride and ethylenic hydrocarbon shown by the formula CnH2n (n is 2-5 or vinyl acetate, 0.01-10pts.wt. silane coupling agent (e.g., vinyltrichlorosilane), and, if necessary, an emulsifying agent or viscosity builder are dissolved or dispersed into an alkali aqueous medium to give a surface treatment solution. The surface of glass fiber is coated with the surface treatment solution and dried. Consequently, glass fiber for providing a molded article of thermoplastic having improved tensile strength, flexural strength, and impact strength is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to glass fibers for reinforcing plastics.

Glass fibers are mixed with thermosetting resins such as epoxy resins and phenolic resins, or thermoplastic resins such as polyolefins such as polyethylene and polypropylene, polyamide resins such as nylon 6 and nylon 6.6, and acetal resins. It is well known that it significantly improves the strength, dimensional stability, etc. of molded products. The present inventors have conducted extensive research with the aim of further improving the mechanical strength of molded products, and have completed the present invention that achieves this aim. That is, the present invention uses maleic anhydride and CnH2
It exists in a glass fiber for plastic reinforcement surface-treated with a copolymer with an ethylene hydrocarbon or vinyl acetate represented by n (where n=2 to 5) and a silane coupling agent.

The present invention will be explained in detail below.

In the present invention, the fumonomer forming a copolymer with maleic anhydride is selected from the group consisting of ethylene hydrocarbons (e.g. ethylene, propylene, imbutylene, etc.) represented by CnH2n (where n=2 to 5) and vinyl acetate. 2M1 or more may be used in combination. Moreover, other unsaturated monomers may be used in combination with the main amount of the above-mentioned fumonomers.

The ratio of maleic anhydride and the above-mentioned ethylene hydrocarbon or vinyl acetate in the copolymer of the present invention is not particularly limited, but in order to make the resulting copolymer soluble in an alkaline aqueous medium, It is preferable that the maleic anhydride component is contained in a large proportion, for example, 30 to 75 moles. A copolymer having a proportion within this range is soluble in an alkaline aqueous medium.

When the proportion of maleic anhydride used decreases due to the alkali components (alkali metal compounds, ammonia, amines) in the aqueous solution, the degree of hydrophilicity of the resulting copolymer decreases. For such materials, an emulsifier can be added and the glass fibers can be surface-treated in the form of an emulsion.

The silane coupling agent used in the present invention includes:
Any silane coupling agent conventionally used for surface treatment of glass fibers can be used. For example, it may have at least one organic group directly bonded to a silicon atom, and may further bond a halogen atom such as chlorine. The organic groups mentioned above include alkyl groups such as methyl, ethyl, propyl, and hexyl, alkenyl groups such as vinyl, unacycloalkyl groups such as cyclohexyl, alkoxy groups such as ethoxy, or these organic groups are amino substituents. Examples include those having the following. Specific examples include vinyltrichlorosilane, vinyl-tris-β-methoxyethoxysilane, vinyltriethoxysilane, and γ-aminopropyltriethoxysilane. One or more types of these coupling agents may be used.

The ratio of the maleic anhydride copolymer and the coupling agent used can vary over a wide range, but usually, for example, the former 1
The latter is preferably used in a ratio of 0.01 to 10 parts by weight per 100 parts by weight.

The above-mentioned maleic anhydride copolymer and silane coupling agent are mixed in an aqueous medium, and if necessary, an emulsifier or other auxiliary agent such as a thickener is added, and with this, glass fiber is spun and manufactured. If it is applied during the process or after being manufactured and dried, a coating consisting of the above-mentioned copolymer and coupling agent is formed on the surface of the glass fiber.

Glass fibers of the present invention obtained as described above, c) polyolefins such as polyethylene and polypropylene,
It is used to strengthen thermoplastic resins such as polyamides such as nylon 6.6 and nylon 6, polyesters such as polyethylene terephthalate and polybutylene terephthalate, polycarbonate, acetal resin, polyphenylene oxide, and acrylonitrile-styrene copolymer. It is possible to obtain molded products with excellent physical properties in terms of tensile strength, bending strength, and impact strength. The glass fiber reinforced nylon of the present invention also has excellent water resistance. Furthermore, the glass fibers of the present invention can also be used to strengthen thermosetting resins.

Next, the present invention will be described in detail, but these are representative examples to help understand the present invention, and the present invention is not limited to these examples.

Example 1 A copolymer consisting of maleic anhydride and a comonomer shown in Table 1 below in an approximately 1:1 molar ratio was dissolved in an ammoniacal aqueous solution (
(concentration 0.5%), stir well, and add r-
Aminopropyltriethoxysilane is added and mixed to prepare a glass fiber surface treatment solution. In this case, the above copolymer (as solid content) 2. The silane compound was used in an amount of 0.6 parts by weight based on parts by weight of D.

The above-mentioned surface treatment liquid is applied to glass fibers having a diameter of 13 μm that are produced as filaments by melt-spinning using an applicator installed in the middle of being wound around a rotating drum, and then concentrated, and then dried. A fiber bundle covered with a coating consisting of a copolymer and a silane coupling agent was obtained (1).The glass fiber bundle was then cut into three lengths, added to nylon 6.6, and constantly heated. This R-let was molded into a molded product by injection molding. The tensile strength, bending strength, bending modulus, and Izot impact strength of this product are shown in Table 1 below. In Table 1, ss is the strand solid, i.e., the solid content coated on the glass fiber (
The weight percent of the total amount of maleic anhydride copolymer and silane coupling agent is shown (abbreviated as SS in Example 2 and below). Further, GC indicates the glass content, that is, the amount of glass fiber in the reinforced resin in weight % (this is also abbreviated as GC in Example 2 and below).

Example 2 This example shows that when nylon 6.6 is used as the reinforcing resin, the resulting resin molded product has a high water resistance.

Comonomers copolymerized with maleic anhydride, SS and G
C as shown in Table 2 below, and surface-treated glass fibers were prepared in the same manner as in Example 1, and a reinforced resin was produced using this, and the tensile strength of the fiber was measured. The results are shown in Table 2.

Table 2 DI in tensile strength (Y is measured as it is for the molded product of glass fiber reinforced resin, WIi8T is the DI for the molded product at 14
The value was measured after 20 hours of immersion in hot water at 2° C. The retention rate is the WET measurement value/DRY measurement value, and represents the degree of water resistance. An example of the tensile strength of the conventional glass fiber reinforced nylon 6.6 is DRY 14.4, WET 7.1, and retention rate 49, and the water resistance of the product according to the present invention is significantly improved.

Example 3 This example shows the case where polybutylene terephthalate is used as the resin to be reinforced.

Comonomers co-united with maleic anhydride, SS and G
C was shown in Table 6 below, and other surface-treated fibers were prepared in the same manner as in Example 1, and a reinforced resin was made using the fibers. The physical properties of the obtained product are shown in Table 6.

Example 4 In this example, the reinforcing resins were polyethylene terephthalate (abbreviated as PET in the table below) and highly modified polyphenylene oxide (abbreviated as PPO in the table below) and acrylonitrile-styrene copolymer (abbreviated as As in the table below)'f : Indicates when used.

Comonomers copolymerized with maleic anhydride, SS and G
Glass fibers having C as shown in Table 4 below and surface-treated in the same manner as in Example 1 were produced, and a reinforced resin was produced using the glass fibers. The physical properties of the obtained product are shown in Table 4.

Example 5 In this example, reinforcement of polypropylene was carried out. Comonomer copolymerized with maleic anhydride and GCi
Surface-treated glass fibers were prepared in the same manner as in Example 1 except as shown in Table 5 below, and a reinforced resin was manufactured using the glass fibers. Table 5 shows the physical properties of the obtained product.

Claims (1)

[Claims] Glass fiber for plastic reinforcement surface-treated with a copolymer of maleic anhydride and an ethylene hydrocarbon or vinyl acetate represented by CnH2n (where n=2 to 5) and a silane coupling agent.