凹凸棒石/弹性体协同改性聚丙烯

Synergistic Modification of Polypropylene with Attapulgite/Elastomer

通过熔融共混法,制得了聚丙烯(PP)/硅烷偶联剂改性的天然凹凸棒石(OATT)/聚烯烃弹性体(POE)三元复合材料和PP/OATT、PP/凹凸棒石(ATT)二元复合材料,研究了复合材料的力学性能、流变性能和热性能。力学性能研究结果表明:在二元体系中,复合材料的拉伸强度随着ATT和OATT含量提高而提高,但是在相同凹凸棒石含量下,PP/OATT复合材料的拉伸强度提高更显著;PP/ATT复合材料的冲击强度与纯PP比较没有提高反而下降,而PP/OATT的冲击强度则随着OATT含量提高先增后降,并在OATT含量为1%时达到最大值。在PP/OATT/POE三元体系中,当固定PP/OATT比例为100/5时,POE含量达到5%,复合材料冲击强度为8.91KJ/m2,与未加POE体系相比提高了21.10%;当POE含量增加到15%时,复合材料冲击强度提高了44.80%,并且其拉伸强度基本得到保持,说明POE和OATT对PP具有明显的协同增韧增强效果。流变曲线分析表明,在低的剪切速率下,改性的凹凸棒石对PP复合材料的流动性能有较好改善。DSC分析结果表明,POE和OATT均能有效地促进PP结晶,并且OATT/POE二元组分对PP具有更有效的协同异相成核作用。

Polypropylene（PP）/attapulgite modified with silane coupling agent（OATT）/polyolefin elastomer（POE） ternary composites and PP/OATT binary composites were prepared by melt blending method,and were investigated systemically for its mechanical properties,rheological and crystallizing behaviors.It was found that the addition of OATT and ATT to PP matrix enhanced significantly the tensile strength （σ_s）,and the σ_s of PP/OATT was higher than that of PP/ATT.Moreover,the impact strength of PP/OATT was higher than PP and increased with addition of OATT content from 0 to 1 wt%.In comparison,the impact strength of PP/ATT was inferior to PP.The results of ternary PP /POE/ OATT composites analysis showed that when fixing the weight ratio of OATT/PP to 5/100,when the content of POE was up to 5%,the impact strength of composite reached to 8.91 kJ/m^2,increasing 21.10%;when POE was 15%,the impact strength increased（44.8%）,and its tensile strength of composites almost did not change.From the rheological analysis curves,the addition of OATT decreased the melt fluidity of composites obviously in the low shear rate.In addition,differential scanning calorimetry（DSC） analysis confirmed that POE and OATT were effective in promoting the crystallization of PP.