Storage life prediction under pre-strained thermally-accelerated aging of HTPB coating using the change of crosslinking density  

作　　者：Yong-qiang Du Jian Zheng Gui-bo Yu 

机构地区：[1]Shijiazhuang Campus,Army Engineering University,Shijiazhuang,050003,China

出　　处：《Defence Technology（防务技术）》2021年第4期1387-1394,共8页Defence Technology

基　　金：This work was supported by the National Defense Pre-Research Projects[grant number ZS2015070132A12002].

摘　　要：In order to predict the storage life of a certain type of HTPB(hydroyl-terminated polybutadiene)coating at 25℃ and analyze the influence of pre-strain on the storage life,the accelerated aging tests of HTPB coating at 40℃,50℃,60℃,70℃ with the pre-strain of 0%,3%,6%,9%,respectively were carried out.The variation regularity of the change of crosslinking density was analyzed and the aging model of HTPB coating under pre-strained thermally-accelerated aging was proposed.The storage life of HTPB coating at 25℃ was estimated by using the Berthelot equation as the end point of the aging life with a 30% decrease in maximum elongation.The results showed that the change of crosslinking density of HTPB coating increased with the increase of aging temperature and aging time,and decreased with the increase of pre-strain.Under 0% prestrain,the relationship between the change of crosslinking density of HTPB coating and the aging time can be described by the logarithmic model with the confidence probability greater than 99%.The stress relaxation phenomenon existed under 3%,6%and 9%pre-strained aging.The aging model considering chemical aging and pre-strain was established with the confidence probability greater than 90%.The storage life of HTPB coating was 15.2935 years at 25C under 0% prestrain,which was reduced by 13.9007%,75.6949% and 89.7859% under 3%,6% and 9% pre-strain,respectively.The existence of pre-strain has a serious impact on the storage life of HTPB coating,therefore,the pre-strain should be avoided as much as possible during the actual storage.

关 键 词：HTPB coating Crosslinking density Aging model Storage life prediction Berthelot 

分 类 号：V435[航空宇航科学与技术—航空宇航推进理论与工程]