Method for improving the mechanical performance and thermal stability of unsaturated polyester resin/waste-printed circuit board nonmetals composites via isocyanate chemistry

To strengthen the interfacial interactions between waste-printed circuit board (WPCB) nonmetals and unsaturated polyester resin (UPE) and achieve a high performance in UPE composites, a novel type of polyurethane prepolymer (pre-PU) with dual functions was prepared by the reaction of isophorone diisocyanate with poly(ethylene glycol). We found that pre-PU was chemically bonded to the surface of the WPCB nonmetals, and a stronger interaction between the WPCB nonmetals and UPE matrix was formed. The mechanical properties and thermal stability of the UPE/pre-PU-WPCB nonmetal composites showed remarkable improvements compared with those of the UPE/WPCB nonmetals composites, in particular, the impact toughness, which increased threefold. We envision that this promising modification method will not only open up new opportunities for the preparation of high-performance plastic composites but also provide a guarantee for the practical industrial application of WPCB nonmetals. (C) 2017 Wiley Periodicals, Inc.