聚甲基丙烯酰亚胺结构泡沫的极低温环境稳定性  

The Property Stability of Polymethacrylimide Structural Foam at Extremely Low Temperatures

作　　者：史亚伟 高坤[2] 胡爱军[1] 李克迪 王志媛[1] 杨海霞[1] 杨士勇[1,4] Ya-wei Shi;Kun Gao;Ai-jun Hu;Ke-di Li;Zhi-yuan Wang;Hai-xia Yang;Shi-yong Yang(Key Laboratory of Science and Technology on High-Tech Polymer Materials,Institute of Chemistry,Chinese Academy of Sciences,Beijing 100190;Aerospace Research Institute of Materials&Processing Technology(ARIMT),Beijing 100076;Cashem Advanced Materials Hi-Tech Co.,Ltd.,Shaoxing 312369;School of Chemical Sciences,University of Chinese Academy of Sciences,Beijing 100049)

机构地区：[1]中国科学院化学研究所极端环境高分子材料院重点实验室,北京100190 [2]航天材料及工艺研究所,北京100076 [3]浙江中科恒泰新材料科技有限公司,绍兴312369 [4]中国科学院大学化学科学学院,北京100049

出　　处：《高分子学报》2023年第12期1817-1825,共9页Acta Polymerica Sinica

基　　金：国家自然科学基金(基金号51973225)资助项目.

摘　　要：采用甲基丙烯腈(MAN)与甲基丙烯酸(MAA)作为共聚单体,通过自由基本体共聚合反应首先制备MAN-MAA共聚树脂板;然后,经加热发泡得到聚甲基丙烯酰亚胺(PMI)硬质闭孔结构泡沫.研究发现,所制备PMI泡沫在室温下具有优良的力学性能、耐热性能及隔热性能;经液氢(LH_(2):−253℃)和液氧(LO_(2):−183℃)极低温环境处理1 h后,PMI泡沫仍表现出优良的化学结构及综合性能稳定性;在−150℃下,PMI泡沫的压缩强度和压缩模量高于室温(25℃),拉伸强度和断裂伸长率分别达到室温的70%和48%.In view of the application demand for rigid structural foam in the extremely low-temperature environment in the aerospace field,polymethacrylimide(PMI)structural closed foams were prepared by thermal foaming of the copolymer sheet prepared by bulky radical copolymerization of methylacrylonitrile(MAN)and methacrylic acid(MAA).The reaction mechanism of PMI foam preparation process was analyzed.The thermal and mechanical properties of PMI foam as well as its structural and performance stability after being treated with liquid hydrogen(LH_(2):−253℃)and liquid oxygen(LO_(2):−183℃)were systematically studied.Experimental results indicated that the imide cyclization reaction was the main reaction in the foaming process,which occured above 160℃.The PMI foams obtained showed excellent mechanical,thermal and heat insulation properties at ambient temperature.The glass transition temperature of PMI foam was 202℃,and the initial thermal decomposition temperature was higher than 300℃.The compressive strength was 3.99 MPa with density of 111 kg/m3.After treated in liquid hydrogen and liquid oxygen at extremely low temperatures for 1 h,no obvious change was detected on the chemical structures and combined properties of the PMI foams.Otherwise,the PMI foam showed excellent mechanical properties at−150℃,with compressive strength and modulus which were higher than that measured at room temperature(25℃),and tensile strength and elongation at break which were 70%and 48%of that at 25℃,respectively.The excellent high and low temperature resistance of PMI foam makes it expected to be used in the preparation of the structural parts of cryogenic propellant tank.

关 键 词：聚甲基丙烯酰亚胺泡沫 液氢 液氧 燃料贮箱 

分 类 号：TQ328[化学工程—合成树脂塑料工业]