Influence of dynamic vulcanization and phase interaction on the swelling behavior of the thermoplastic elastomeric blends of nylon-6 and acrylate rubber in various solvents and oil

The swelling behavior of thermoplastic elastomeric blends of nylon-6 and acrylate rubber (ACM) has been studied in various solvents and oil at different temperatures. The blends, both with and without dynamic vulcanization, show excellent solvents and oil resistance at elevated temperature. The interfacial reaction between nylon-6 and ACM phases as well as the dynamic crosslinking of the ACM phase during melt blending tremendously improve the solvent resistance of the blends. A simple thermodynamic model, based on the Flory-Huggins equation, is applied to find out the constraining effect of the continuous nylon-6 matrix (which is the least swellable phase) on the extent of equilibrium swelling of the dispersed ACM phase in toluene at 25 degrees C. The diffusion coefficients of various solvents and the activation energy of diffusion of toluene in 40 : 60 (w/w) dynamically vulcanized blend have been reported. The occurrence of interfacial reaction and the existence of nylon-B-ACM graft copolymers are also supported by the dynamic mechanical thermal analysis of the blends. (C) 1998 John Wiley & Sons, Inc.