Artículos de revistas
Toward microphase separation in epoxy systems containing PEO-PPO-PEO block copolymers by controlling cure conditions and molar ratios between blocks
Fecha
2006-09Registro en:
Larrañaga, M.; Martin, M. D.; Gabilondo, N.; Kortaberria, G.; Eceiza, A.; et al.; Toward microphase separation in epoxy systems containing PEO-PPO-PEO block copolymers by controlling cure conditions and molar ratios between blocks; Springer; Colloid and Polymer Science; 284; 12; 9-2006; 1403-1410
0303-402X
1435-1536
CONICET Digital
CONICET
Autor
Larrañaga, M.
Martin, M. D.
Gabilondo, N.
Kortaberria, G.
Eceiza, A.
Riccardi, Carmen Cristina
Mondragon, I.
Resumen
Nanostructuring of thermosetting systems using the concept of templating and taking advantage of the self-assembling capability of block copolymers is an exciting way for designing new materials for nanotechnological applications. In this first part of the work, reactive blends based on stoichiometric amounts of a diglycidylether of bisphenol-A epoxy resin and 4,4́-diaminodiphenylmethane cure agent modified with three poly(ethylene oxide)-co-poly(propylene oxide)-co-poly(ethylene oxide) block copolymers were studied. Cure advancement of these systems was analyzed by differential scanning calorimetry. The experimental results show a delay of cure rate, which increases as copolymer content and PEO molar ratio in the block copolymer rise. Infrared spectroscopy shows that PEO block is mainly responsible of physical interactions between the hydroxyl groups of growing epoxy thermoset and ether bonds of block copolymer. These interactions are mainly responsible for the delaying of cure kinetics. The molar ratio between blocks also has a critical influence on the delaying of the cure rate. A mechanistic approach of cure kinetics allows us to relate the delay of cure as a consequence of block copolymer adding to physical interactions between components.