화학공학소재연구정보센터
Polymer, Vol.99, 598-604, 2016
Functional group tolerance of AOTEMPO-mediated peroxide cure chemistry
Delayed onset formulations for the peroxide-initiated crosslinking of a range of commodity polymers are described. 4-Acryloyloxy-2,2,6,6,-tetramethylpiperidin-N-oxyl (AOTEMPO) is effective for controlling the crosslinking dynamics and yields of linear low density polyethylene (LLDPE), poly(ethylene-co-vinyl acetate) (EVA), poly(ethylene-co-propylene) (EPR), and poly(ethylene-co-propylene-co-ethyl-idenenorbornadiene) (EPDM). However, the cure additive is inefficient for butadiene-based materials such as 1,2-polybutadiene (vinyl-BR) and cis-1,4-poly(butadiene) (cis-BR), since macroradical trapping by AOTEMPO stunts diene-monomer oligomerization, thereby eliminating multiple crosslinks that cannot be restored by a single polymer-bound acrylate group. Additional crosslink yield losses arise from allylic alkoxyamine instability, the details of which are revealed by independent H-1 NMR and rheology studies. (C) 2016 Elsevier Ltd. All rights reserved.