| EPDM分布形态对动态硫化PP/EPDM共混物增韧效果的影响及其机理的研究 |
| Influence of EPDM Distributive Morphology on Toughened Effect of Dynamically Vulcanized PP/EPDM Blends and Its Mechanism |
| |
| DOI： |
| 中文关键词: 动态硫化 PP EPDM 共混物 增韧 机理 形态结构 |
| 英文关键词: |
| 基金项目: |
|
| 摘要点击次数: 913 |
| 全文下载次数: 788 |
| 中文摘要: |
| 采用扫描电子显微镜(SEM)技术研究了乙烯质量分数分别为0.53，0.45 和0.75 的3种EPDM与PP组成的动态硫化共混物的形态结构特征及其增韧效果。结果表明，当EPDM中乙烯质量分数在0.45～0.55之间时，EPDM的结构规整性差、熔融粘度高、与PP相容性小，动态硫化的实质是使EPDM分散颗粒由大变小、粒度均化、分布均匀，增大共混剪切强度有利于提高这种EPDM的增韧效果。当EPDM中乙烯质量分数达到0.75时，EPDM中因出现均聚PE序列结构而呈现部分结晶性，熔融粘度低，与PP相容性增大，动态硫化后EPDM分散颗粒由小变大，并同时形成“亚网结构”，强化化学交联反应可提高网络密度及网络连续性，从而提高增韧效果，而提高共混剪切强度，反而会使增韧效果下降。 |
| 英文摘要: |
| The morphologic characteristics and toughened effect of three EPDMs in dynamically vulcanized PP/EPDM blends were investigated by SEM and the ethylene contents in the said EPDMs were 53%，45% and 75% by weight respectively.The results showed that the EPDM with the ethylene content between 45%～55% by weight gave lower structure regularity，higher melting viscosity and poor compatibility with PP，the dynamic vulcanization resulted in smaller dispersive EPDM granules，more uniform granule size and distribution，and the increase of shearing strength in blending was benefitial to the toughening effect of this EPDM；and the EPDM with the ethylene content up to 75% by weight gave partial crystallinity due to the formation of homopolymerized ethylene in EPDM，lower melting viscosity and better compatibility with PP，the dynamic vulcanization resulted in greater dispersive EPDM granules and a subnetwork structure，the network density and continuity were increased by promoting the chemical crosslinking reaction and thus the toughened effect was increased，in contrast，the toughened effect was decreased by increasing the shearing streng th in blending. |
|
|
查看全文
查看/发表评论 下载PDF阅读器 |
| 关闭 |
