Thermally controlled molecular disassembly of a crosslinked polymer network by the incorporation of sterically hindered urea linkages

Abstract

AbstractCrosslinked polymer networks are excellent materials for multiple applications. However, although their crosslinked structure gives them many positive attributes, it also makes them intractable. Therefore, it is exceedingly difficult to reprocess crosslinked networks without exposure to extreme degradation conditions. In this work, we were able to create a crosslinked network that showed controlled disassembly upon stimulus. It was found that a controlled network disassembly process could be invoked by the incorporation of sterically hindered urea linkages into the polymer network. The network was shown to disassemble upon exposure to heat, whereas in the absence of heat, the network was found to maintain its crosslinked structure. The disassembly temperature could be varied by careful selection of the cleaving agent. This work focuses on showing the controlled network disassembly of a crosslinked polymer matrix as a function of temperature. Herein, we describe the factors that control the disassembly temperature and conclude with a possible mechanism for the disassembly process. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 856–864, 2002