Preparation And Property Study On Epoxidized Polysiloxane Composite

Silicone rubber is one of elemento-organic polymers, which belongs to non-oil resources, and widely used in electronic, aerospace, biomedical fields. However, SiR has some defects, such as low mechanical properties, poor hydrophility, poor oil-resistance, low temperature crystalliazation. Epoxidation is a simple and effective chemical modification method. Epoxy group is a polar and reactive group that can improve oil-resistance and hydrophility, and be be further chemical modified, which has huge economic value in industry application.Firstly, we synthesize Polymethyl-vinyl siloxane rubbers (MVQ) with different vinyl contents and different viscosity (Mn 3?25* 104 g/mol) by anionic ring-opening polymerization. It is indicated that vinyl group can break chain regularity and low temperature crystalliazation, increase chain rigidity to improve heat resistance property.We synthesize epoxidized silicone rubbers (ESiR) with different epoxy contents and different viscosity by direct method. It is indicated that reaction conversation can be over 90% when the polymer concentration is 30 g/L and proportion of MCPBA to double bonds is 1.3. Besides, epoxy group can improve cold tolerance and heat resistance of silicone rubber. On the basis of the test in laboratory, we study the large scale production of ESiR synthesis and use 10 L reactor to synthesis ESiR. Besides, we prepare ESiR/slica composite by polymer processing method. Epoxy group can leads to much better filler dispersion and a significant reduction of Payne effect.We study the structure and properties of Wacker R401 silicone rubber. We find that R401 SiR has excellent filler disperstion, high intensity of over 10 MPa, high tear strength of over 37.19 KN/m and stress whitening performance. In addition, R401 silicone rubber has ultra wear-resistance and ablation resistance property.