Controlled grafting of cellulose diacetate

Cellulose diacetate (CDA) was acylated with 2-bromoisobutyryl bromide (BriBr) or with dichloroacetyl chloride (ClAcCl) giving polyfunctional macroinitiators for ATRP grafting of styrene (St), MMA and butyl acrylate (BuA). Under various reaction conditions, macroinitiators with variable degrees of functionalisation could be prepared. The macroinitiators with 2-bromoisobutyryl (BriB) groups were grafted with St or BuA, those with dichloroacetyl (ClAc) functions were used for graft copolymerization of MMA. Graft copolymers with chemically different grafts as well as tunable lengths and densities of grafts were synthesized in this way. Poly(CDA- g-St) and poly(CDA- g-MMA) were further used as macroinitiators of BuA polymerization, giving poly[CDA- g-(St- b-BuA)] and poly[CDA- g-(MMA- b-BuA)] graft copolymers with diblock grafts.