Temperature dependence of the mechanical properties and the inner structures of natural rubber reinforced by in situ polymerization of zinc dimethacrylate

In this work, the tensile property of natural rubber (NR) reinforced by zinc dimethacrylate (ZDMA) at various temperatures was studied. The results showed that the strain-induced crystallization of NR chains at larger elongation and the ionic crosslinks are two of the main reasons for the high tensile strengths of the NR/ZDMA composites, and they afforded the apparent tensile strength at different temperature range. Strainstress curves revealed that the composites could not undergo strain-induced crystallization above 80 degrees C. The results of Rubber Process Analyzer 2000 (RPA2000) confirmed that the effective ionic crosslinks were weakened and destroyed by high temperatures. The crosslink density, determined by an equilibrium swelling method, was used to characterize the structure variation during stretching at different temperatures. At last, the results of thermal gravimetric analysis (TGA) indicated that the ionic crosslinks improved the thermal stability of the NR/ZDMA composites to some extent. (c) 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013