退火对PPR管材专用料结晶行为及抗低温性能的影响

摘要

The effect of annealing on mechanical properties and crystallization behaviors of polypropylene random copolymer (PPR) dedicated pipe materials were analyzed by SEM,differential scanning calorimetry (DSC),XRD and polarized optical microscopy (POM).The results showed that when compared with unannealed sample,PPR annealed at 120 ℃ for 6 h indicated desired impact toughness and the relative better comprehensive mechanical properties under room temperature and low temperature (0-23 ℃).The impact strength at 23 ℃ was 51.61 kJ/m2 which was 1.9 times than that of unannealed sample.And the impact strength at 0 ℃ was also up to 33.86 kJ/m2 which was 2.9 times than that of unannealed PPR.%通过对无规共聚聚丙烯(PPR)管材专用料进行退火处理,采用SEM、DSC、XRD、POM等表征技术,分析了退火对PPR力学性能及结晶行为的影响规律.结果表明,在常温及低温(0～23℃)条件下,与未退火的PPR比较,退火工艺为120℃退火6h的材料冲击韧性最理想,其综合力学性能最好.在23℃时的冲击强度为51.61kJ/m2,是未退火样品的1.9倍.0℃时的冲击强度也高达33.86kJ/m2,是未退火样品的2.9倍.