苯乙烯类塑料耐老化性能研究

STUDY ON ANTI-AGING PERFORMANCE OF STYRENIC RESINS

对纯聚苯乙烯(PS)、高抗冲聚苯乙烯(HIPS)、PS/(苯乙烯/丁二烯/苯乙烯)共聚物(SBS)共混物、添加助剂的PS和HIPS等5组试样进行紫外光加速老化。表征了5组试样老化前后的力学性能、特性粘度、分子链结构的变化。研究表明,紫外光加速老化使材料的力学性能降低,表层发生龟裂;表层的溶液粘度下降较明显,距厚度大于0.4mm时其粘度下降缓慢;傅立叶变换红外光谱谱图中在1720cm-1处出现明显的吸收峰,表明有CO生成;纯HIPS、添加助剂的HIPS和PS/SBS共混物在910、966cm-1处的吸收峰强度明显减弱,表明发生了烯烃碳碳双键的断裂,添加助剂的HIPS老化后的透过率保持率最高。

Virgin polystyrene （PS）, high-impact polystyrene （HIPS）, PS/SBS blends, PS and HIPS containing additives were investigated by UV accelerated aging. The mechanical properties, intrinsic viscosity and structural changes of molecular chain of the five groups before and after aging were characterized. The results showed that UV accelerated aging decreased the mechanical properties of samples and cracking occurred on the surface of materials ; the intrinsic viscosity of sample surface significantly declined, while samples with thickness more than 0.4 mm slowly decreased; in the FTIR spectra, a obvious absorption peak appeared at 1720 cm^-1, which indicated the generation of carbonyl groups; the intensity of absorption peaks of virgin HIPS, HIPS with additives and PS/SBS blends at 910 cm^-1 and 966 cm^-1 obviously decreased, and these showed that the carbon-carbon double bonds fractured. The absorption intensity of the samples before and after aging showed that HIPS with additives had the highest absorption retention.