TY - JOUR
T1 - Reactive processing of polymers
T2 - melt grafting of glycidyl methacrylate on ethylene propylene copolymer in the presence of a coagent
AU - Al-Malaika, Sahar
AU - Kong, Wei
N1 - Copyright 2004 Elsevier Science B.V., Amsterdam. All rights reserved.
PY - 2001/2/22
Y1 - 2001/2/22
N2 - Glycidyl methacrylate (GMA) was grafted on ethylene-propylene copolymer during melt processing with peroxide initiation in the presence and absence of a more reactive comonomer (coagent), trimethylolpropane triacrylate (Tris). The characteristics of the grafting systems in terms of the grafting reaction yield and the nature and extent of the competing side reactions were examined. The homopolymers of GMA (Poly-GMA) and Tris (Poly-Tris) and the GMA-Tris copolymer (GMA-co-Tris) were synthesized and characterized. In the absence of the coagent, high levels of poly-GMA, which constituted the major competing reaction, was formed, giving rise to low GMA grafting levels. Further, this grafting system resulted in a high extent of gel formation and polymer crosslinking due to the high levels of peroxide needed to achieve optimum GMA grafting and a consequent large drop in the melt index (increased viscosity) of the polymer. In the presence of the coagent, however, the grafting system required much lower peroxide concentration, by almost an order of magnitude, to achieve the optimum grafting yield. The coagent-containing GMA-grafting system has also resulted in a drastic reduction in the extent of all competing reactions, and in particular, the GMA homopolymerization, leading to improved GMA grafting efficiency with no detectable gel or crosslinking. The mechanisms of the grafting reactions, in the presence and absence of Tris, are proposed.
AB - Glycidyl methacrylate (GMA) was grafted on ethylene-propylene copolymer during melt processing with peroxide initiation in the presence and absence of a more reactive comonomer (coagent), trimethylolpropane triacrylate (Tris). The characteristics of the grafting systems in terms of the grafting reaction yield and the nature and extent of the competing side reactions were examined. The homopolymers of GMA (Poly-GMA) and Tris (Poly-Tris) and the GMA-Tris copolymer (GMA-co-Tris) were synthesized and characterized. In the absence of the coagent, high levels of poly-GMA, which constituted the major competing reaction, was formed, giving rise to low GMA grafting levels. Further, this grafting system resulted in a high extent of gel formation and polymer crosslinking due to the high levels of peroxide needed to achieve optimum GMA grafting and a consequent large drop in the melt index (increased viscosity) of the polymer. In the presence of the coagent, however, the grafting system required much lower peroxide concentration, by almost an order of magnitude, to achieve the optimum grafting yield. The coagent-containing GMA-grafting system has also resulted in a drastic reduction in the extent of all competing reactions, and in particular, the GMA homopolymerization, leading to improved GMA grafting efficiency with no detectable gel or crosslinking. The mechanisms of the grafting reactions, in the presence and absence of Tris, are proposed.
KW - reactive processing
KW - grafting of GMA
KW - reactions on EP copolymer
KW - goagent for grafting
UR - http://www.scopus.com/inward/record.url?scp=0035252507&partnerID=8YFLogxK
UR - http://onlinelibrary.wiley.com/doi/10.1002/1097-4628%2820010222%2979:8%3C1401::AID-APP70%3E3.0.CO;2-4/abstract
U2 - 10.1002/1097-4628(20010222)79:8<1401::AID-APP70>3.0.CO;2-4
DO - 10.1002/1097-4628(20010222)79:8<1401::AID-APP70>3.0.CO;2-4
M3 - Article
AN - SCOPUS:0035252507
SN - 0021-8995
VL - 79
SP - 1401
EP - 1415
JO - Journal of Applied Polymer Science
JF - Journal of Applied Polymer Science
IS - 8
ER -