Stannoxane oligomers and polymers

Oligomeric and polymeric stannoxanes having the general formula {A figure is presented} where X = RCOO, ArO, RSO₃, Cl and 0 < n < 100, were prepared by heating a carboxylic acid, phenol, sulphonic acid or hydrochloric acid with polymeric dibutyltin oxide at molar ratios less than 1. The basic reaction is probably the cleavage of a stannoxane bond in the polydibutyltin oxide and formation of shorter polymers having the acid residue as end groups. Polyorganotin esters having a required number of dibutyltin recurring units having the general formula {A figure is presented} were prepared by heating dicarboxylic acids with polydibutyltin oxide at appropriate ratios, or by reacting oligomeric dichlorostannoxanes with the disodium salts of dicarboxylic acids under interfacial conditions. Some of the properties of the oligomers were investigated.