碱式硫酸镁形貌对碱式硫酸镁/聚丙烯复合材料力学性能的影响  

Effect of magnesium oxysulfate morphology on the mechanical properties of magnesium oxysulfate/polypropylene composites

作　　者：党力[1,2] 乃学瑛[1] 朱东海[1] 许乃才[1,2] 董亚萍[1] 李武[1] 

机构地区：[1]中国科学院青海盐湖研究所,西宁810008 [2]中国科学院大学,北京100049

出　　处：《复合材料学报》2017年第7期1517-1525,共9页Acta Materiae Compositae Sinica

基　　金：青海省自然科学基金(2014-ZJ-938Q);中国科学院西部之光(Y412031006)

摘　　要：以三种不同形貌的碱式硫酸镁(颗粒状(MOS_P)、晶须状(MOS_W)和扇形(MOS_S))为填料、月桂酸(LA)为改性剂、聚丙烯(PP)为树脂基体,通过熔融共混法制备了系列MOS/PP复合材料。SEM结果显示,改性后的MOS_P和MOS_W在基体中分散均匀,但与基体PP的相容性依然较差;MOS_S/PP样品中同时存在着尺寸较大且形貌复杂的MOS_S和部分分散的MOS_W,界面缺陷更加明显。广角X-射线衍射(WXRD)结果表明,三种MOS均能诱导β-晶型PP的产生,与月桂酸的加入无关,其中MOS_P诱导效果更明显。力学性能测试结果表明,三种形貌MOS的加入稍降低了基体的屈服强度,一方面是MOS与基体相容性差,另一方面归结于β-晶型PP生成;相比之下,MOS_W加入能较好地保持PP基体的屈服强度和拉伸断裂韧性,且明显增强基体的模量,主要归因于MOSW较大的长径比;MOS_P对基体的增韧效果更为明显,一方面是由于MOS_P诱导生成β-晶型PP的效果强于MOSW和MOS_S,另一方面则可能是由于MOS_P较大的比表面积附着了较多的脂肪酸盐,其增塑效果更强。Series of magnesium oxysulfate/polypropylene（MOS/PP）composites magnesium oxysulfate particle（MOS_P）,magnesium oxysulfate whisker（MOS_W）,and magnesium oxysulfate sector（MOS_S）were prepared via melt blending method using magnesium oxysulfate（magnesium oxysulfate particle（MOS_P）,magnesium oxysulfate whisker（MOS_W）,and magnesium oxysulfate sector（MOS_S））as fillers,lauric acid（LA）as modifier and PP resin as the matrix.SEM results indicate that both modified MOS_P and MOS_W are fine dispersed in the PP matrix,whereas the incompatibility issue still exist.For MOS_S/PP composites,MOS_S with huge size and complicated morphology and partial dispersed MOS_W are coexisted,with more interface defects observed.Wide angle X-ray diffraction（WXRD）results suggest that addition of MOS can induce the formation of β-crystal PP which is irrelevant to LA,especially for the MOS_P/PP sample.The incorporation of three kinds of MOS slightly decreases yield strength of the PP matrix.One reason is the incompatibility between MOS and the PP matrix,and the formation of β-crystal is another important reason.In contrast,introducing MOS_W can maintain the yield strength and tension fracture toughness and reinforce the modulus of PP matrix obviously,which is mainly due to the high aspect ratios of whisker morphology.In addition,the most obviously toughening effect happens on the MOS_P/PP composites for two reasons.On the one hand,MOS_P is more efficient for inducing β-crystal PP as compared with MOS_W and MOS_S.On the other hand,the more fatty acid salt attached to the surface of MOS_P results in the stronger plastification effect to the PP matrix.

关 键 词：碱式硫酸镁 聚丙烯 形貌 力学性能 Β-晶型 

分 类 号：TB332[一般工业技术—材料科学与工程]