有机累托面/聚烯烃弹性体协同增韧补强聚丙烯的研究

分别研究了有机累托石粘土(OREC)、聚烯烃弹性体(POE)改性的聚丙烯(PP)以及POE／OREC／PP三元改性体系的冲击强度、拉伸强度及断裂伸长率。结果表明，在粘土添加量为2phr时(per hundred resin)可对PP同时实施增强、增韧。OREC与POE有协同增韧PP的作用。在OREC添加2phr时，POE／OREC／PP复合材料的强度大于相同用量的POE／PP二元体系的强度。在三元体系中，当POE用量15phr时，复合材料的冲击强度比纯PP提高204％，比POE／PP提高15．6％，拉伸强度比纯PP下降15．6％，比POE／PP提高22．6％。扫描电子显微镜分析(SEM)表明，三元体系呈现多相分散，在研究范围内，分散相尺寸越大，粒径分布越宽，复合材料的韧性越高。

On Toughening PP (Polypropylene) Synergistically with OREC/POE (Organic Rectorite/Polyolefin Elastomer)

When used in products such as refrigerators and washing machines, PP alone is unsatisfactory due to its brittleness. It has been necessary to toughen it with POE, but such toughening is done at the price of too much loss of strength. Our experience led us to try using both OREC and POE because in this way the reduction in strength may be less than using either OREC or POE. Our trial confirmed that using both OREC and POE can bring about less reduction in strength. To our surprise, we found in our trial the synergistic effect of toughening PP with OREC/POE, i.e., toughening is better than using either OREC or POE alone. Comparing OREC/PP with POE/PP, we found that POE/PP is in general better than OREC/PP in toughness. So what we did with OREC/PP was only that we found that both impact strength (Fig.2(a)) and tensile strength (Fig.2(b)) of OREC/PP peak at 2 phr (per hundred resin) OREC, PP being the resin. We fixed OREC at 2 phr of PP, and then obtained the variation of impact strength with content of POE (expressed in parts per hundred resin) for both POE/OREC/PP, and POE/PP (Fig.3(a)); we found that when POE is 15 phr of PP, the impact strength of POE/OREC/PP is 15.6% higher than that of POE/PP. Again fixing OREC at 2 phr of PP, we obtained the variation of tensile strength with content of POE for both POE/OREC/PP and POE/PP (Fig.3(b)); we found that when POE is 15 phr of PP, the tensile strength of POE/OREC/PP is 22.6% higher than that of POE/PP. Thus POE/OREC/PP can be made both tougher and stronger than POE/PP, and is therefore more suitable for use in products such as refrigerators and washing machines. The SEM (scanning electron microscope) photos in Fig.4 show the morphology of POE/OREC/PP as a multiphase structure; as POE varies from 5 phr to 10 phr and then to 15 phr of PP, both the size of dispersed phase and the toughness increase.