私密直播全婐app免费大渔直播,国产av成人无码免费视频,男女同房做爰全过程高潮,国产精品自产拍在线观看

當前位置:> 首頁 > 論文著作 > 正文
PMMA/mesoporous silica nanocomposites: Effect of framework structure and pore size on thermomechanical properties
作者:Faai Zhang, DongKeun Lee, Thomas J. Pinnavaia
關鍵字:PMMA; composite, mesoporous
論文來源:期刊
具體來源:Polymer Chemistry
發表時間:2010年

Mesoporous forms of silica (MS) with different framework structures and pore sizes , including hexagonal MCM-41 (2.4 nm), cubic MCM-48 (1.9 nm), hexagonal SBA-15 (7.0 nm) and mesocellular silica foam MSU-F (24.8 nm), were examined as functional additives in the preparation of poly(methyl methacrylate) (PMMA) / mesoporous silica nanocomposites made by in-situ emulsion polymerization and compression molding.  All of the composites at 5 wt % loadings of MS, exhibit improved thermal stability, an elevated glass transition temperature, and an enhanced storage modulus in comparison to the pristine polymer.  MSU-F silica with the largest framework pore size provides the composite with the best improvement in thermomechanical properties.  In general, the improvements in thermal stability and modulus diminish with decreasing framework pore size of the silica additive.  For composites made from MCM-41 and MCM-48 silicas with similar pore sizes, the 3D MCM-48 structure provided superior benefits. The improvements in thermomechanical properties for the composite are attributed to the confinement of polymer in large pore channels, especially those with a 3D structure.  

主站蜘蛛池模板: 蓬安县| 康保县| 昌平区| 凉城县| 长丰县| 噶尔县| 乐昌市| 辽阳市| 游戏| 石棉县| 洪洞县| 柳林县| 红安县| 眉山市| 江华| 虞城县| 驻马店市| 湘潭市| 交城县| 临沭县| 紫金县| 古交市| 宝应县| 民县| 依兰县| 徐州市| 格尔木市| 宁陕县| 伽师县| 正宁县| 绵阳市| 建湖县| 博湖县| 高碑店市| 永顺县| 无锡市| 朝阳市| 井冈山市| 河曲县| 同心县| 景东|