In situsynthesis of polyamide 6/MWNTs nanocomposites by anionic ring opening polymerization

Determination of thermal degradation for high-performance thermoplastic composites manufactured by laser-assisted automated fibre placement

In in situ consolidation of thermoplastic composites by laser-assisted automated fibre placement (AFP), high laser irradiation temperature can improve the fluidity of the resin matrix, which usually enhances the performances of composites. However, it leads to a tendency for thermal degradation as the resin matrix of the composites is exposed to high temperatures for a long time. The thermal degradation behaviours of continuous carbon fibre (CF)-reinforced polyphenylene sulfide (PPS) composites during in situ consolidation by laser-assisted AFP were studied. A thermogravimetric analysis shows that the thermal degradation of CF/PPS composites is quite complex, with multi-step reactions. The thermal degradation of the composites was further analysed via kinetic methods. A thermal degradation kinetic model of the resin matrix was obtained and verified. According to the kinetic model, the thermal degradation of the composites under different placement conditions was predicted. The results were confirmed by Fourier-transform infrared spectroscopy and scanning electron microscopy. With the combination of the kinetic model, AFP in situ consolidation, and characterisation techniques, processing parameters such as laser irradiation temperature and placement speed can be adjusted and optimised.

Polymers and Related Composites via Anionic Ring-Opening Polymerization of Lactams: Recent Developments and Future Trends

This paper presents a comprehensive overview of polymers and related (nano)composites produced via anionic ring opening polymerization (AROP) of lactams. It was aimed at surveying and showing the important research and development results achieved in this field mostly over the last two decades. This review covers the chemical background of the AROP of lactams, their homopolymers, copolymers, and in situ produced blends. The composites produced by AROP were grouped into nanocomposites, discontinuous fiber, continuous fiber, textile fabric, and self-reinforced composites. The manufacturing techniques were introduced and the most recent developments highlighted. Based on this state-of-art survey some future trends were deduced and as their "driving forces" novel and improved manufacturing techniques identified.