CS272893B1 - Undersaturated amidotrialkoxysilanes - Google Patents

Abstract

The invention concerns unsaturated silanes of the formula HOOCCH=CHCONHC2H4NR<1>C3H6Si(OR<2>)3 where R<1> represents COCH=CHCOOH and R<2> is methyl or ethyl prepared by addition of maleate hydride and 3-(2-aminoetyl) aminopropyltrialkoxysilane, suitable as a binding agent for modification of fillers for reinforcement of plastics. It is suitable to use in the form of ammonium salts.

Description

The invention relates to unsaturated amidotrialkoxysilanes and their ammonium salts.

Substituted trialkoxysilanes have found significant industrial application for silanizing various surfaces, especially silicate, in order to achieve special application properties, especially in modification of fillers for reinforcement of plastics and rubbers, production of catalysts, chromatographic supports, treatment of textiles, building materials, anti-corrosion treatment of metals.

Various N-substituted amino silanes are known (U.S. Pat. No. 3,627,806, 3,922,436,

934,459, 3,317,577, 3,458,556, 3,956,535, 3,755,354, 3,959,327, 4,209,455, 4,284,548), the use of which is constantly being expanded by the preparation of new derivatives with special properties. One condition for the successful application of silanes to modify fillers for plastic reinforcement is that, in addition to providing a reactive filler surface, they do not worsen its wettability with the respective plastics. In the application research we have found that the silanes of the invention are effective binding agents.

The present invention provides unsaturated amidotrialkoxysilanes of the general formula HOOCCH = OHOOSHO ^ MR ^ HgSifOR ^ where:

R @ 1 is -COCH = OHCOOH R @ ² methyl or ethyl and their ammonium salts.

The preparation of these compounds can be accomplished by coupling maleic anhydride to aminosilanes such as 3- (2-aminoethyl) aminopropyltrimethoxethoxysilane and 3- (2-aminoethyl) aminopropyltriethoxysilane. It is preferable to conduct the addition with a water or water-soluble solvent.

The compounds prepared are effective as binding agents for treating fillers, especially glass fibers. They can be applied in acidic and alkaline environments, after neutralization, mainly with nitrogenous bases such as ammonia, alkanolamines, morpholine and the like.

The invention is illustrated by way of examples.

Example 1 * 3 v

The preparation of the silane of the above general formula wherein R is methyl was carried out in a flask equipped with a stirrer and a thermometer. 94.1 g of isopropyl alcohol and 50 g of 3- (2-aminoethyl) aminopropyltrimethoxysilane were introduced into the apparatus. While stirring, 44.1 g of maleic anhydride was gradually added so that the temperature did not rise above 60 ° C. The prepared silane has an acid number of 142.1 mg KOH / g (134.1 mg KOH / g theory) Si content of 6.81% (Si theory - 6.727%). It is water soluble and provides stable aqueous solutions in both acid and alkaline environments. Neutralization was performed by mixing 40 g of silane solution with 14.2 g of triethanolamine, 5.8 g of monoethanolamine.

Example 2

The preparation of silane of the formula wherein R ² is ethyl is performed to that in Example 1. The apparatus was charged 87.1 g of isopropyl alcohol, 50 g of 3- (2-aminoethyl) aminopropyltriethoxysilane and 37.1 g of maleic anhydride. The prepared silane has an acid number of 133.1 mg KOH / g (theory 121.8 mg KOH / g), Si content - 6.14% (Si theory - 6.098%). It is practically limitlessly soluble in water and polar solvents.

CS 272893 EL

Evaluation of tensile strength was performed according to ČSN 64 0605, flexural strength according to ČSN 640607, flexural modulus, tensile according to ČSN 640614. From the obtained results we can see that by using silanes according to the invention the mechanical properties of reinforced polyamide are significantly improved. 6

Example 3

The silane prepared in Example 1 was used to treat glass fibers with an average thickness of 15 µm. The silanized fibers used were prepared by applying a composition consisting of 10% by weight of polyurethane dispersion (33% by weight dry matter) 0.5% by weight of silane dry matter, 0.2% by weight of acetic acid, 0.5% by weight of aminoamide acetate to the filament glass fibers. 0.3% lithium chloride and the remainder to 100% water. Unsilanized fiber was prepared by treating the glass fibers with the composition without the addition of silane. The treated fibers, after drying at 125 ° C for 6 h, were cut to 6 mm in length and used as a 30% by weight polyamide-6 reinforcement.

A - Unsilanized glass fiber

B-3-Aminopropyltriethoxysilane

C-cyclohexenylethyltriethoxysilane

D-3- (2-aminoethyl) aminopropyltrimethoxysilane

E-3-glycidoxypropyltrimethoxysilane

P - The invention

The fiber-polymer mixture was homogenized at 247 ° C. The prepared granulate was processed at 260 ° C on an injection molding machine for standardized test specimens by the procedure according to ČSN 64 3610. The achieved physical-mechanical properties of the reinforced polyamide-6 are given in the table.

table

Glass fiber A B C D £ P tensile strength MPa 39.4 60.6 43.8 61.1 58.6 65.4 bending strength MPa 53.7 75.1 62.7 74.4 69.2 83.2 tensile modulus MPa TV 3205 3163 3432 3290 3186 4220 flexural modulus MPa 2335 2608 2561 2750 2650 3042

Claims (1)

P R E D Μ E T INVENTION Unsaturated amidotrialkoxysilanes of the general formula HOOCCH = CHCONHC ₂ H ₄ NR ¹ G 3 H ₆ SifOR ² ) 3 R @ 1 is a residue of the structure --COCH3 CHCOOH R ^{2 is} methyl or ethyl and their ammonium salts.