Prepn. of soluble polymers contg. tri:fluoromethyl gps. - by reaction of corresp. polymers contg. carboxylic acid, ester] or anhydride] gps. with sulphur tetra:fluoride and hydrogen fluoride

摘要

Prodn. of soluble, ungelled CF3 gp.-contg. polymers (I) from COOR gp.-contg. polymers (II) (with R = H, 1-10C alkl or acyl), by reaction of (II) with a molar excess of SF4 (w.r.t COOR gps. in II) at -20-120 deg. C in the presence of a molar excess of HF (or source of HF) and opt. inert organic solvent and/or diluent. Polymers (I) of formula -Am-Bn- (with A = methyl (meth)acrylate or butyl acrylate unit; B = -CH2-CH(CF3)-) or -D1-Em-Bn- (with D = methyl acrylate and E = acrylic acid units; or with D = ethylene or propylene and E = ethyl acrylate units; or with D = 1-hexene and E = methyl acrylate units), or of formula (III), (IV) or (V); m, n = 0-1; l+m+n = 1; x = 50-15,000. USE/ADVANTAGE - (I) are useful for the prod. of vulcanised prods. The process enables the prodn. of (I) from the corresp. COOR gp.-contg. polymers, in good yield and with high selectivity. The prods. have high thermal stability, low oil-swelling, good mechanical properties and very good low-temp. flexibility, and are suitable for the prodn. of seals, axle sleeves, piping, driving belts etc. for automobile and aerospace applications.