李崇俊
,
宇航材料工艺
doi:10.3969/j.issn.1007-2330.2006.01.002
综述了中空纤维释放黏结剂的裂纹愈合及近期开发的机敏裂纹自愈合复合材料的研究进展.对后者微胶囊促使的机敏裂纹自愈合进行了详尽的阐述,其中包括愈合剂和催化剂的结构、微胶囊的形成和外表连接催化剂、愈合剂系统原位聚合反应、纯环氧树脂基体和复合材料中的裂纹自愈合、愈合效率及愈合复合材料微观表征等方面.一个典型的双相自愈合系统是包含于微胶囊中的二聚环戊二烯(DCPD),通过埋于环氧基体中的钌络合物催化剂进行开环转位聚合反应(ROMP),形成新的聚合物来愈合裂纹.在纯环氧树脂基体中,上述自愈合系统在室温下的愈合效率可高达90%,而在碳纤维复合材料中室温下的愈合效率大致是45%,在80℃可提高到80%.降冰片烯(Norbornene)及其衍生物具有同以上系统相似的自愈合功能.三聚呋喃和四聚马来酰亚胺可在无催化剂作用下,进行热可逆的、无终止的交联聚合反应,自动愈合裂纹.同时,对以上三种自愈合剂系统及复合材料的特点进行了比较.
关键词:
机敏材料
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愈合
,
修补
,
自愈合
,
聚合物基复合材料
Wu YAO
,
Jie LI
材料科学技术（英）
A superfine slag powder (SP) made from granulated blast furnace slag incorporating activators by using special milling technique, was used as supplementary cementitious material in high performance concrete (HPC), replacing part of the mass of normal Portland cement. The effects of the SP on the workability, mechanical and crack self-healing properties of HPC were studied. The hydration process and microstructure characteristics were investigated by X-ray diffraction (XRD) and scanning electron microscopy (SEM) techniques, respectively. The crack self-healing capacity was evaluated by Brazilian test. The test results indicate that the SP has especially supplementary effect on water reducing and excellent property of better control of slump loss. The concrete flowability increases remarkably with the increase of SP replacement level in the range of 20% to 50%. The compressive and splitting tensile strengths of HPC containing SP are higher than the corresponding strength of the control concrete at all ages. The crack self-healing ability is highly dependent on SP content of HPC.
关键词:
Superfine slag powder
,
null
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