What Determines the Lamellar Orientation on Substrates
What Determines the Lamellar Orientation on Substrates
复制标题
DOI：
10.1021/ma102973w
复制
发表时间：
2011-04
期刊：
影响因子：
5.5
通讯作者：
Juping Yang;Q. Liao;Jianjun Zhou;Xi Jiang;Xiao-hong Wang;Yang Zhang;Shi-dong Jiang;Shouke Yan;Lin Li
中科院分区：
文献类型：
--
作者：
Juping Yang;Q. Liao;Jianjun Zhou;Xi Jiang;Xiao-hong Wang;Yang Zhang;Shi-dong Jiang;Shouke Yan;Lin Li
用原子力显微镜(AFM)和透射电子显微镜(TEM)研究了聚氧乙烯(PEO)在聚乙烯醇(PVA)、溶菌酶(LYSO)、聚乙烯吡咯烷酮(PVPY)和聚丙烯酸(PAA)四种非晶膜上的再结晶行为。结果表明，过冷度和PEO/衬底相互作用对PEO晶体的生长行为都有显著的影响。相应地提出了一个热力学模型，在该模型中，片层取向与最佳的一次形核有关。我们根据衬底的过冷度和表面自由能来预测片层取向。片层取向从边向平的转变取决于基材的临界表面自由能，它等于聚合物熔体的表面张力。
The recrystallization behavior of poly(ethylene oxide) (PEO) on four amorphous films of poly(vinyl alcohol) (PVA), lysozyme (LYSO), poly(vinylpyrrolidone) (PVPY), and poly(acrylic acid) (PAA) was investigated using atomic force microscopy (AFM) and transmission electron microscopy (TEM). The results show that both the degree of supercooling and PEO/substrate interactions have pronounced influence over the growth behavior of the PEO crystals. A thermodynamic model has been proposed accordingly, in which the lamellar orientation is associated with the favorite primary nucleation. We predict the lamellar orientation based on the degree of supercooling and the surface free energy of substrate. The transition of lamellar orientation from edge-on to flat-on is determined by a critical surface free energy of the substrate which is equal to the surface tension of the polymer melt.