Degradation Characterization of Ethylene-Propylene-Diene Monomer (EPDM) Rubber in Artificial Weathering Environment

Abstract

Ethylene-propylene-diene monomer containing 5-ethylidene-2-norbornene as diene was exposed to artificial weathering environment produced by a xenon lamp light exposure and weathering equipment for different periods of time. The changes of surface color and mechanical properties were monitored by spectrophotometer, computer-controlled tensile testing and hardness measurements. Crosslink density of ethylene-propylenediene monomer specimens was measured by the solvent swell method. The results showed that the surface of ethylene-propylene-diene monomer became yellower due to the form of carbonyl group. The degradation process proceeded predominantly via cross-linking. With increase in crosslink density, the tensile strength increased and the elongation at fracture decreased.

Rheumatoid Arthritis Patients Are Free of Filarial Infection in an Area Where Filariasis is Endemic: Comment on the Article by Pineda et al

“…EPM is well known to have higher oxidative stability and better environmental stability and thermal properties than those of diene‐based elastomers, such as, polybutadiene rubber or polyisoprene (PIP) rubber, due to the absence of unsaturated bonds in their polymer backbones 1, 2. The importance of ethylene–propylene copolymers is increasing strongly based on its superiority in resistance to oxygen, ozone and weathering resistance, chemical inertness, and lightness of color 3, 4. The ethylene–propylene copolymers could be processed with a number of additives and could be the most widely used elastomer for specialty applications, such as, in the automotive industry, rubber mechanical goods and construction materials, and impact modifiers for coatings and engineering plastics 5–8.…”