Study On Silicon-modified Polyurethane Adhesive

Polyurethane is a kind of polymer material with excellent adhesive bonding properties. But it surfers from some deficiency such as bad heat resistance and heat aging while silicone has better heat resistance and heat aging properties. So the modification of polyurethane with silicone can combine the good properties of the two and make the adhesive force, wear resistance, weather resistance and chemical medicine resistance of silicone increased in some event. And the resins can be cured at ambient temperature.In the case of non-solvent, silicone oligomers were prepared by the hydrolysis of alkoxyl silicone, the optimum preparation conditions were found. And then oligomers with R/Si=1.2 and Me/Ph=0.71 were synthesized under aforesaid conditions; the esterification was progressed between glycol, 1,4-butylene glycol, polyester polyol and silicone oligomers and then samples containing different amount silicone were prepared. FT-IR (Fourier transform infrared), GPC (Gel permeation chromatography) were employed to characterize the oligomers and samples and it was determined that the products were target compounds. Furthermore, the adhesive property, mechanical property, waterproofness, heat resistance and oil resistance were explored by systematically investigating. It was found that the properties of the products were influenced by the synthesis strategy greatly, which mainly depended on the amount of the silicone.As far as the waterproofness of silicon-modified polyurethane adhesive was concerned, in the term of adhesive property, products which had larger amount silicone had better waterproofness at elevated temperature (70 ℃) and hardly changed any more at ambient temperature. Neither the polyurethane of modified nor the pure polyurethane had any changes in shear strength of ambient temperature or elevated temperature while keeping in water of ambient temperature for 720 hours, which demonstrated that both the polyurethane of modified and the pure polyurethane had good waterproofness at ambient temperature; in the term of mechanical properties, products containing larger amount of silicone had better waterproofness. The waterproofness of polyurethane of modified and the pure polyurethane of ambient temperature was better than that...