不同因素对聚碳酸酯/聚对苯二甲酸乙二醇酯共混物的性能影响研究

Study on the effects of different factors on the properties of PC/PET blends

通过挤出和注塑制备聚碳酸酯/聚对苯二甲酸乙二醇酯(PC/PET)共混物,探究成核剂对PC/PET共混物的结晶形态、热行为、形貌及力学性能的影响。此外,对相容剂添加量和PC/PET质量配比等变量也做了性能影响分析。最佳条件为:相容剂添加0.5%、PC/PET=3/7、成核剂TiO_(2)添加1%。适量粒径均匀、细小的TiO_(2)作为成核剂能很好地分散在PC/PET基体内,得到的PC/PET共混物形貌平整光滑,拉伸强度、弹性模量及冲击强度分别为40.5MPa、7654.0N/mm^(2)及14.3J/m,在DSC曲线上出现明显的冷、热结晶峰,热结晶的结晶温度均高于冷结晶,且DMA结果显示成核剂的加入使玻璃化转变温度降低,不相容PC相和PET相的Tg不断靠近。

In this paper,the blends of polycarbonate/polyethylene terephthalate(PC/PET)were prepared by extrusion and injection process.The effects of nucleators,compatibilizer dosage and PC/PET mass ratio on the crystalline morphology,thermal behavior,morphology and mechanical properties of PC/PET blends were investigated.The optimal condition were:0.5%dosage of compatibilizer,3/7 of PC/PET ratio,and 1%dosage of TiO_(2) nucleator.The tensile strength,elastic modulus and impact strength were 40.5MPa,7654.0N/mm^(2) and 14.3J/m,respectively,when the appropriate amounts of TiO_(2) with uniform small particle sizes as nucleator to disperse well in the PC/PET matrix and depict a flat and smooth morphology simultaneously.Parallel with above,there were conspicuous cold and hot crystallization peaks on the DSC curve,and the crystallization temperature of hot crystallization was higher than that of cold crystallization.DMA results showed that the addition of nucleators lowered the glass transition temperature and brought the Tg of incompatible PC and PET phases closer.