Study On Preparation And Properties Of Flame Retardant Poly(Butylene Succinate)/ZnO Composites

Poly(butylene succinate)(PBS), a kind of aliphatic polyester, has excellent biodegradation and biocompatibility. With similar mechanical strength and processability, it is hopeful to replace polyolefine in some application fields such as packaging, agriculture films, medical devices and daily used goods. However, the disadvantages concerning with low mechanical strengths and poor thermal stability, thus the modification of PBS through copolymerization and blending attracts much interest. Furthermore, its easy flammability with dripping restricts the applications in electric and decorative materials. A lot of interest focuses on the development of flame retardant PBS.With ammonium polyphosphate (APP) and Melamine cyanurate (MCA) as flame retardants and zeolite (ZEO) as flame-retardant synergist, the flame retardant PBS was prepared by melt-blending process. The optimal APP/MCA/ZEO of the flame retardant formulation was28:9:3and determined by the vertical burning test (UL-94) and limited oxygen index (LOI). The influences of APP/MCA/ZEO flame retardant on the thermal stability and mechanical properties of PBS were investigated. The effect of ZnO fillers on the of mechanical properties, thermal degradation kinetics and crystallization behaviors of PBS and its composites were studied systematically. It was explored preliminarily how ZnO nanoparticals (nano-ZnO) affect the bacteriostasis of PBS and its flame retardant composites.The LOI value of PBS sample containing25wt%flame retardant was more than36.0and it passed UL-94V1. The anti-dripping of flame retardant PBS can be improved by using peroxide cross-linking agent:dripping of flame retardant PBS can be inhibited to pass UL-94V0by adding0.1wt%Benzoyl peroxide (BPO). The surface modification using silicane coupling agent3-aminopropyltriethyloxy silane(APS) can improve the dispersity of ZnO fillers in PBS matrix and the interface compatibility between fillers and the matrix, which are characterized by FT-IR, XPS, TEM and SEM. The characterizations of TG, DSC and mechanical testing show that surface modified nano-ZnO can increase the tensile and flexural strengths and improve the crystallization. Under a certain addition, nano-ZnO can catalyze the formation of the inorganic insulation layer to add carbon left, thus to improve the thermal stability, flame retardancy, and bacteriostasis property of the PBS composites. While tetra-needle ZnO whispers (T-ZnOw) have not so obvious corresponding effects as nano-ZnO.The present work aims at the experimental support for the design and preparation of flame retardant biodegradable polyesters. This dissertation should have positive significance in PBS replacing polyolefine and protecting environment.