Chemical ageing of linseed oil based thermosets

MIRNA ALEJANDRA MOSIEWICKI; OSCAR ROJAS; MARÍA ROSARIO SIBAJA; JULIO BORRAJO; MIRTA INÉS ARANGUREN

Río de Janeiro, Brazil

Congreso; MACRO 2006 - World Polymer Congress; 2006

IUPAC

Rigid thermoset polymers prepared by free radical polymerization of styrene with linseed oil based resins, were evaluated under different environmental conditions and at different times after their preparation. The oxygen in the environment is enough to produce chemical changes in these polymers affecting the properties of the cured materials. These changes have been analyzed by mechanical and dynamical-mechanical tests. An increase of the modulus with the time was observed after exposing the samples to dry conditions, or humid environments with 60% relative humidity, or with additional UV radiation. Acceleration of the polymerization reactions occurs when the materials are subjected to UV radiation. In particular, a large effect on the glass transition temperature is observed after a few hours of exposition.