弹性体改性高抗冲聚苯乙烯的力学行为Ⅰ．拉伸和动态力学性能

THE MECHANICAL PROPERTIES OF ELASTOMER MODIFIED HIGHIMPACT POLYSTYRENE Ⅰ.TENSILE AND DYNAMIC MECHANICAL PROPERTIES

研究了高抗冲聚苯乙烯（ＨＩＰＳ）同苯乙烯－丁二烯－苯乙烯热塑性弹性体（ＳＢＳ）、丁苯橡胶（ＳＢＲ）、高顺式聚丁二烯橡胶（ＰＢＲ）共混物的拉伸性能及动态力学性质。ＳＢＳ改性的ＨＩＰＳ试样具有最大的断裂能，最大的断裂伸长率，较高的拉伸杨氏模量、屈服强度，屈服点过后有明显的应变硬化现象。ＳＢＲ改性的ＨＩＰＳ也呈现韧性断裂，拉伸过程中有明显的应力发白现象。ＰＢＲ改性ＨＩＰＳ试样表现为脆性断裂，力学性能变劣，３种改性试样的动态力学性能谱同ＨＩＰＳ相比均发生明显变化，表明分子运动的特征发生改变。

The tensile and dynamic properties of the blends for high impact polystyrene(HIPS)with styrene-butadiene-styrene copolymer (SBS),cis-polybutadiene rubber(PBR)and butadiene-stryene rubber(SBR) were studied in this paper. The samples of SBS modified HIPS have the maximum work of rupture,elongation in break and higher tensile Yang's modular as well as yielding strength.The strain-hardening was observed after yield-point.The samples of SBR modified HIPS also showed ductile fracture and significant stress-whitening phenomena was observed.The samples of PBR modified HIPS showed brittle fracture.Their mechanical properties changed poor.The three modified samples showed significant effect compared with HIPS in viscoelastical spectrum, which disclosed the variation of molecular motion characters.