Abstract
Ultraviolet and heat-curable polyurethane acrylate prepolymers were synthesized from 4,4’-diphenyl methane diisocyanate, polyethylene adipate diol, polyhexamethylene carbonate diol, polycaprolactone diol and 1,6- hexamethylene diamine , acrylic acid. Effects of nature of the soft segments on the physical properties were investigated. It was found that the thermal stability increased from polycarbonate diol to polyester diol. Tensile modulus and strength decreased for polyurethane acrylate based poly (ethylene adipate) diol. DSC scans show that all of the model polymers exhibit thermal transitions including a glass transition below –35oC. These soft elastic segment structures, in addition to the physical and chemical cross-linked nature of hard segment, provide enough crosslink sites to have elastomeric behaviour. Keywords: polyurethane acrylate, cross-linked, mechanical properties, thermal behaviour