Morphology, rheology, and mechanical properties of dynamically cured EPDM/PP blend: Effect of curing agent dose variation

Autor: Xiao, Han-Wen, Huang, Shi-Qiang, Jiang, Tao
Zdroj: Journal of Applied Polymer Science; 5 April 2004, Vol. 92 Issue: 1 p357-362, 6p
Abstrakt: The structure development, rheological behavior, viscoelastic, and mechanical properties of dynamically cured blend based on the ethylene–propylene–diene terpolymer (EPDM) and polypropylene (PP) with a ratio of 60/40 by weight were studied. The variation of two-phase morphology was observed and compared as the level of curing agent was increased. Meanwhile, as the level of curing agent increased, viscosity as a function of shear stress always increased at a shear stress range of 2.2 × 104 to 3.4 × 105 Pa at the temperature of 200°C, yet viscosity of the blend approached each other at high shear stress. Dynamic mechanical spectra at different temperatures show that dynamic modulus (E') of the blend exhibits two drastic transitions corresponding to glass transition temperature (Tg) of EPDM and Tg of PP, respectively. In the blends Tgs of EPDM increase and Tgs of PP almost remain unchangeable with an increase in curing agent level. Tensile strength increased, yet elongation at break decreased as the level of curing agent is increased. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 357–362, 2004
Databáze: Supplemental Index