Synthèse de composé photoréticulables, 9. Modification du polybutadiène carboxytéléchélique par des monomères acryliques

Abstract

Abstract The addition of mercaptoacetic acid upon radical initiation onto carboxytelechelic polybutadienes ( 1 ) which have an average mass M̄ n = 4400 gives polyacids having about twelve carboxylic groups. The reaction is followed by 13 C NMR, 1 H NMR and by GPC. The thiol disappears according to a first order law. Besides, the value of the modification rate obtained from acido‐basic titration confirms that obtained from NMR. In a second step, 2,3‐epoxypropyl methacrylate is added to the acid groups to obtain an insaturated and carboxylated polydienic oligomer 5 . An application of these oligomers processed with a reactive diluter shows their high cross‐linking ability under UV irradiation and confirms the improvement of the flexibility properties compared to those of traditional insaturated oligomers.