Preparation And Properties Of KH-560 Aqueous Solutions

Silane coupling agents are a class of organosilicone compounds containing two different chemical groups.One end of the molecule is a kind of hydrolyzable group such as alkoxy group,and the other end is connected to the silicon atom by a carbon chain.Silane coupling agents can combine organic and inorganic materials with very different properties to produce high performance composites.However,in the process of use,silane coupling agents will release volatile small molecule compounds,such as methanol,ethanol and so on,which will cause certain an adverse influence on the environment and operators.The purpose of this paper is to hydrolyze silane coupling agent to prepare stable silane aqueous solution without low molecular alcohol and use it in aqueous system.Firstly,the hydrolysis and condensation process ofγ-（2,3-epoxypropoxy）propyl trimethoxy silane（KH-560）was studied by the electrical conductivity method.The effects of silane concentration,hydrolysis method and p H value on the hydrolysis process were discussed.The results show that the stability of the hydrolysate is good when the p H is 2-4.On the basis of the above experimental results,a series of KH-560 aqueous solutions with different solid contents were prepared under the catalysis of formic acid or acetic acid at different concentrations.The physical and chemical properties of the products,such as p H value,epoxy value,particle size and molecular weight,were tested,and the effect of storage time on the properties were also studied.The optimal formulation for the preparation of KH-560 aqueous solution was 35.0 g of deionized water,2.0 m L of methanol,0.25 m L of formic acid and 15.0 g of KH-560.Instead of KH-560 pure product,the prepared silane aqueous solution is applied to treat the glass fiber.The wetter equipped with silane aqueous solution is stable and the drawing operation is normal.The treated glass fiber has normal physical properties such as linear density,combustible content,moisture content,breaking strength,and wear resistance.The tensile and shear properties of the composite of the treated glass fiber and epoxy resin meet the relevant standards.In addition,the expected experimental results are also obtained for the polyester staple fiber treated with an amino-modified-polyxiloxane emulsion cured with the prepared silane aqueous solution.In this paper,the co-hydrolysis of KH-560 and methyl trimethoxy silane was also studied,and the mixed silane aqueous solution was prepared with 0.5%of formic acid as catalyst.The influence of mass ratio of two kinds of silanes on the stability of the product was discussed.The results show that when the mass ratio of KH-560 to methyltrimethoxy silane is greater than 7:3,the product is a transparent solution with good stability.The physical and chemical properties of the product,such as p H value,epoxy value and molecular weight,have been tested.The mixed silane aqueous solution was used to modify the surface of inorganic powder filler Al（OH）₃.The results showed that the oil absorption value of the treated Al（OH）₃ powder decreased with the increase of the amount of silane aqueous solution under the experimental conditions,and the viscosity of the cpomposite with methyl silicone oil（viscosity 56 c P）also decreased.