结晶和去润湿竞争条件下分子结构对超薄膜表面形貌的影响(英文)  

Effect of Molecular Structure on the Surface Morphology of Ultrathin Films by Competing Crystallization and Dewetting Processes

作　　者：袁伟忠[1,2] 张凤波[3] 袁金颖[1] 谢续明[3] 洪啸吟[1] 

机构地区：[1]清华大学化学系,有机光电子与分子工程教育部重点实验室,北京100084 [2]同济大学材料科学与工程学院,纳米与生物高分子材料研究所,上海200092 [3]清华大学化学工程系,北京100084

出　　处：《物理化学学报》2010年第4期1157-1163,共7页Acta Physico-Chimica Sinica

基　　金：supported by the National Natural Science Foundation of China(20874056,20836004,20974058);National Key Basic Research Program of China(973)(2009CB930602)~~

摘　　要：将星形支化结构的聚己内酯,包括六臂星形聚己内酯(HPCL)和树枝状星形聚己内酯(DPCL),以及线形聚己内酯(LPCL)室温旋涂于云母片上,通过原子力显微镜(AFM)观察分子结构对星形支化聚己内酯超薄膜的润湿-去润湿性质的影响.在旋涂过程中,薄膜的形成受去润湿和结晶竞争的控制.差示扫描量热(DSC)测试结果表明,当相对分子质量相同时,结晶性的顺序是:DPCL最弱,HPCL次弱,LPCL最强.依据分子结构和相对分子质量的影响,即去润湿和结晶竞争的结果,LPCL、HPCL和DPCL的超薄膜表现出不同的表面形态,包括尺寸不同的完整的球晶、开口的球晶、树枝状片、分散的颗粒.Star-branched poly（ε-caprolactone） （PCL） including hexa-armed star-shaped PCL （HPCL）,dendritic PCL （DPCL）,and linear PCL （LPCL） were spin-coated onto mica substrates at room temperature.The effect of molecular structure on the wetting-dewetting behavior of ultrathin film （about 15 nm） was investigated with atomic force microscopy （AFM）.During spin-coating,film formation is governed by competing dewetting and crystallization processes.According to differential scanning calorimetry （DSC）,the crystallizability of DPCL is weaker than that of HPCL which is weaker than that of LPCL,when they have the same relative molecular mass.Depending on the molecular structure and the relative molecular mass of PCL,the competition between crystallization and dewetting results in ultrathin films of LPCL,HPCL,and DPCL with surface morphologies such as perfect spherulites,open spherulites,dendritic lamellae,and dispersed droplets of different sizes.

关 键 词：润湿 分子结构 去润湿 结晶 超薄膜 

分 类 号：O484[理学—固体物理]