降解剂和成核剂在PP混凝土纤维中的应用

Application of Degradation Agent and Nucleating Agent to PP Fibre for Concrete

通过聚丙烯（PP）可控流变和成核改性试验，确定了过氧化物降解剂和成核剂的种类与用量，并研究了它们对混凝土用PP纤维料性能的影响。结果表明，过氧化物降解剂A和成核剂N4的效果较好；降解剂A的较佳用量为0．04％（质量分数），成核剂N4的较佳用量为0．06％～0．10％（质量分数）；降解剂A对PP的拉伸屈服应力基本没有影响，而随着降解剂A用量的增加，PP的相对分子质量分布和弯曲模量则有逐渐变小的趋势；成核剂N4对PP的熔体流动速率（MFR）有增大的作用，但随着成核剂N4含量的进一步提高，PP的MFR则趋于恒定。

The variety and the dosage of peroxide degradation agent and nucleating agent were determined , and the influences on properties of special material of PP fibre for concrete were also studied through the controlled rheological and nucleating modification testing . The results show that peroxide degradation agent A and nucleating agent N4 are good; while the contents of degradation agent A is 0. 04% （mass fraction） and nucleating agent N4 is 0. 06 %-0. 10% （mass fraction）, the best mechanical properties are achieved. The content of degradation agent A has no influence on the tensile strength at yield , but with the increase of it, the MWD and flexural modulus of PP are decreased gradually. Though the MFR of PP is increased with the increasing of nucleating agent N4 content, when it is keep on increasing, the MFR of PP is invariable.