Solvent Assisted Pressure-Free Surface Welding and Reprocessing of Malleable Epoxy Polymers

• DOI: 10.1021/acs.macromol.6b00858
• Publication Date: 2016-07-21T16:25:30Z
• Authors: Qian Shi; Kai Yu; Martin L. Dunn; Tiejun Wang; H. Jerry Qi
• Keywords: Thermosetting polymer

Covalent adaptable networks (CANs; also known as dynamic covalent or vitrimers) are appealing for developing simple and efficient techniques recycling thermosetting polymers. In this paper, ethylene glycol (EG) is used a solvent to enable pressure-free surface welding, repair, of malleable epoxy where the transesterification-type bond exchange reaction (BER) imparts nature network. At high temperature, EG molecules participate in BER, leading dissolution If allowed evaporate, dissolved can re-form into solid. The effects content, catalyst concentration on EG-assisted BERs investigated. It found that amount be adjusted tune solution/solid transformation: An excessive required dissolve epoxy; other hand, shortage shift back polymer. Furthermore, defines point at which initiates, while degradation rate depends temperature. This new method further damage powder-based reprocessing. does not require pressure achieve properties fresh sample. provides potential opportunities develop facile