尼龙66/聚酚氧树脂共混体系的研究

用熔融共混法制备了尼龙66/聚酚氧共混物， 对其力学性能、 结晶与熔融行为及组 分间相容性进行了表征. 共混物只有一个玻璃化转变温度， 且符合线性加和规则； 观察不 到两相形态， 表明两组分相容. 随聚酚氧含量增加， 尼龙66的冷结晶温度升高、 熔融温 度和熔体结晶温度降低， 结晶和熔融温度范围变宽， 熔融热和结晶热降低. 共混物的屈服 强度、 断裂强度和断裂伸长率均呈正协同效应， 并在聚酚氧含量30％～40％(均为质量分 数)呈极大值. 随聚酚氧含量的增加， 断裂强度与屈服强度的差值变小， 当聚酚氧含量达 到80％时， 二者已无明显差别.

Study of Nylon-66/phenoxy Blends

A series of PA66/phenoxy blends bas been prepared by melt-blending wit h a Brabender-like apparatus. The compatibility of the two polymers, the morphol ogy, the crystallization and the melting behavior, as well as the tensile behav ior of the blends were investigated. The single T_g and one phase mo rphology imply that PA66 is compatible with phenoxy. That may be attributed to t he hydrogen-bonding interaction between the oxygen and the nitrogen of the amide group of PA66 and the hydrogen of the hydroxyl group of phenoxy. With increasing phenoxy content, the cold crystallization temperature of PA66 in the blend increases, whereas the melting temperature and melt crystallization temperature, as well as the heat of fusion and the heat of crystallization decrease. Those phenomena support the conclusion that there is a stonger interaction between the two components, so that phenoxy inhibites the segment motion of PA66 in the blend, making the crystallization more difficult a nd the crystal less perfact. The tensile strength, the yielding strength and the elongation at break are higher than the corresponding linear additive values of the pure components and all show a maximum for the weight fraction of pheno xy from 30% to 40%.