超细碳酸钙填充SEBS/PP热塑性弹性体的性能研究

Properties study of SEBS/PP thermoplastic elastomer by ultrafine calcium carbonate

分别采用超细重质碳酸钙(HX-6000)和超细轻质碳酸钙(306-2)作为无机填料,通过在苯乙烯-乙烯-丁烯-苯乙烯嵌段共聚物(SEBS)/聚丙烯(PP)热塑性弹性体中添加不同含量的超细碳酸钙,并对其综合性能进行系统研究,采用扫描电子显微镜、比表面仪、电子密度计、邵氏硬度计、万能力学性能实验机和熔体流动速率测试仪等表征手段对超细碳酸钙粉体的颗粒大小、微观形貌和比表面积以及SEBS/PP热塑性弹性体的300%定伸强度、密度、硬度和熔体流动速率进行了测试。结果表明,在低填充下306-2分散性比较好,制备的SEBS/PP热塑性弹性体强度较高,HX-6000在提高SEBS/PP热塑性弹性体的强度方面具有更大的优势;随着超细碳酸钙添加量的逐渐增大,SEBS/PP热塑性弹性体的密度和硬度均呈现逐渐增大的趋势,熔体流动速率呈逐渐下降趋势,HX-6000具有更高的熔体流动速率。

In this study,the ultrafine ground calcium carbonate(HX-6000-CaCO 3)and ultrafine precipitated calcium carbonate(306-2-CaCO 3)were uesd as inorganic fillers to modify SEBS/PP thermoplastic elastomer.This paper systematically examined the effects of two fillers contents on the comprehensive properties of SEBS/PP thermoplastic elastomer.The particle size,morphology and specific surface area of CaCO 3 particles were firstly studied,and the 300%stretching strength,density,hardness and melt index of SEBS/PP composites were investigated by scanning electron microscope,BET instrument,electronic hydrometer,Shaw hardness tester,universal testing machine and melt flow indexer.The results showed that the SEBS/PP composites exhibited uniform dispersion and high tensile strength when the content of 306-2-CaCO 3 particles was low,and the HX-6000-CaCO 3 particles had more obvious advantages in improving the tensile strength of composites.In addition,the specific gravity and hardness of the SEBS/PP showed a gradually increasing trend with the increasing of CaCO 3 content in SEBS/PP thermoplastic elastomer.The melt index of composites demonstrated a contrary phenomenon,and the composites filled with HX-6000-CaCO 3 showed a higher melt index copared with that of 306-2-CaCO 3.