液晶聚合物增强PC/PET共混物挤出片材的性能研究

Property of Extruded Sheet of PC/PET Blend Reinforced by LCP

介绍液晶聚合物（ＬＣＰ）对ＰＣ／ＰＥＴ共混体系的增强改性。选用了六种不同熔点的ＬＣＰ引入到ＰＣ／ＰＥＴ共混体系中，用自制的有利于形成定向的口模，将共混物挤出成片材，并测定了拉伸强度、维卡软化点、结晶速率，结果表明：在ＰＣ／ＰＥＴ共混物中，加入少量ＬＣＰ后，拉伸强度可比原体系提高３０％左右，不同熔点的ＬＣＰ影响有差异，熔点太高的ＬＣＰ反而会使体系的拉伸强度下降，维卡软化点未见明显变化，当增大ＬＣＰ用量后，体系的维卡软化点有下降趋势，但并不明显；将熔点与ＰＥＴ达到最大结晶速率的温度相接近的ＬＣＰ引入到ＰＣ／ＰＥＴ体系中，可加快ＰＥＴ的结晶速率，熔点太高或太低的ＬＣＰ其促进作用均不明显。

s The reinforcing action of liquid crystalline polymer (LCP) on PC/PET blend system is described in this paper.Six kinds of LCP of different melting temperatures were applied to PC/PET blend systems,and the rein forced blends were extruded with a special made die which was favourable for the extrudate to be oriented.The tensile strength,Vicat softening point (VSP) and crystallization rate of the extruded sheet were determined.The results showed when a little of LCP was applied to PC/PET blend,the tensile strength of the blend increased for about 30%,depending on the melting point of LCP:when the melting point was too high,the tensile strength of the blend would tend to decrease;the VSP of the blend changed not obviously;when LCP content increased,the VSP of the blend decreased a little.The use of LCP,the melting point of which was close to the temperature at which PET had maximum crystallization rate,to PC/PET blend could speed up the crystallization rate of PET,but when the melting point of LCP was too high or low,the effect of LCP on the crystallization rate was not obvious.