|
Title
Graft copolymerization of methyl methacrylate (MMA) onto cellulose acetate in homogeneous medium: Effect of solvent initiator and homopolymer inhibitor
Authors
CHITTARANJAN ROUTRAY and BIRANCHINARAYAN TOSH
Received
June 29, 2012
Published
Volume 47 Issue 3-4 March-April
Keywords
homogeneous grafting, methyl methacrylate (MMA), grafting efficiency, methylene blue, thermal analysis,mechanism of grafting
Abstract
Cellulose acetate-g-polymethyl methacrylate (CA-g-PMMA) copolymer was synthesized in homogeneous medium,
taking dimethyl sulfoxide (DMSO), 1,4-dioxane, N,N-dimethyl acetamide (DMAc) and acetone as solvents and ceric
ammonium nitrate (CAN), benzoyl peroxide (BPO) and tin(II) 2-ethyl hexanoate [Sn(Oct)2] as initiator. The effects of
solvents and initiators on graft yield (GY) and grafting efficiency (GE) were studied. The viscosity average molecular
weight of grafted PMMA was calculated. The role of methylene blue (MB) as a homopolymer inhibitor and its effect
on grafting was also studied. In the presence of MB the molecular weight of the grafted PMMA reduced and
consequently grafting efficiency and the number of grafts per polymer chain increased. The products were characterized by FTIR and 1
H-NMR analyses and possible reaction mechanisms for different initiators were deduced.
The thermal degradation of the grafted products was also studied by thermogravimetric analysis (TG) and differential
thermogravimetry (DTG).
Link
|
