An Overview of the Flame Retardants for Poly(vinyl chloride): Recent States and Perspective^†

As a versatile star product, poly(vinyl chloride) (PVC) has kept active in our daily life all through since it was invented. However, the severe fire hazard and heavy smoke produced during combustion, particularly the extensively used flexible PVC products, have been puzzling manufacturers and researchers for ages. Over the last decade, multifarious flame retardants and smoke suppressants were developed for PVC materials. In this review, combined literature with the results based on the research from our group, recent emerged flame retardants and smoke suppressants for PVC are introduced. Meanwhile, the flame retardant mechanisms and experimental analysis results are described to understand the relationship between characters of flame retardants (including chemical compositions, structures or morphologies) and fire performance of the composites. The potential substitutes for traditional harmful flame retardant antimony trioxide are discussed aiming to the emphasis on increasing prominent environmental concerns. In particular, one section is dedicated to new approaches for the preparation of novel environmentally friendly and high-efficiency flame retardants. It is hoped that this review will not only summarize the new emerged flame retardants and smoke suppressants for PVC, but also provide the new trend to prompt sequent exploration in both academic research and industrial application.