三聚氰胺-甲醛系凝胶老化过程中的体积收缩影响因素  

Solvent effect on volume shrinkage of Melamine-Formaldehyde gel in aging process

作　　者：张勇[1] 任洪波[1] 张林[1] 万小波[1] 

机构地区：[1]中国工程物理研究院激光聚变研究中心

出　　处：《强激光与粒子束》2007年第8期1299-1302,共4页High Power Laser and Particle Beams

基　　金：国防科技重点实验室基金资助课题(51480030205ZW0802);国家863计划项目资助课题

摘　　要：介绍了三聚氰胺-甲醛凝胶老化过程的溶剂效应及其对体积收缩的影响。从凝胶的离浆-溶胀平衡以及溶剂效应等两个方面对湿凝胶老化过程中的体积收缩作了分析,通过测量形状规则的湿凝胶在溶剂交换和老化过程中的体积变化研究湿凝胶组成、交换溶剂的成分及步骤对凝胶体积收缩的影响。结果表明:控制交换溶剂的组成能显著改善湿凝胶后处理过程中的体积收缩。合适的湿凝胶交换步骤是先使用凝胶体内液体和目标溶剂的混合溶剂进行交换,逐次增大目标溶剂的含量,直至最后使用纯目标溶剂进行交换,即可获得体积收缩较小的湿凝胶体系。Solvent effect and volume shrinkage ratio in melamine-formaldehyde gel aging process were discussed. Volume shrinkage ratio was analyzed from two aspects, the aging-swelling balance and solvent effect. The results implied that the solution compositon （water and ethanol） would control the volume shrinkage ratio in aging process. Appropriate exchange steps for wet gel is that the mixture of the liquid in the gel and target solvent （ethand） is firstly used and the target solvent＇s content gradually rises until it is pure target solvent, then the MF aerogel which has little volume shrinkage is obtained.

关 键 词：三聚氰胺 甲醛 老化 体积收缩 

分 类 号：TQ177[化学工程—硅酸盐工业]