Organosilicon block copolymers - from polysiloxanes and organosilicon elastomers useful as binding agents

摘要

Linear and stearic organosilicon block-copolymers of hydro, alkyl (aryl)polysiloxanes are prepd. by hydrolysing monomeric hydro, alkyl (aryl) silanes of formula RnSiX4-n (where R = H, alkyl, or aryl; n = 2 or 3; X = Cl, R'COO or R'O; and R' is alkyl) in an organic solvent e.g. benzene, xylene or pref. toluene, in the presence of an organosilicon elastomer of formula (I): (where R2 and R3 = H, alkyl or aryl) having a MW 3000-50,000, pref. at 7-63 wt.%, then isolating the prod. and effecting polycondensation. The block copolymers can be used as binding agents for enamels having high resistance to temperature changes for heat isolating materials, foils, powder coating agents, etc.