Department of Polymer Chemistry, Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands.
Langmuir. 2010 Jul 6;26(13):11018-24. doi: 10.1021/la1002622.
The azimuthal helix orientation of the rigid-rod amphiphilic diblock copolypeptides (PLGA-b-PMLGSLGs) of poly(alpha-L-glutamic acid) (PLGA) and poly(gamma-methyl-L-glutamate-ran-gamma-stearyl-L-glutamate) with 30 mol % of stearyl substituents (PMLGSLG) in Langmuir-Blodgett (LB) monolayers was investigated using polarized transmission Fourier transform infrared spectroscopy. The relative position of dipping with respect to the previous transfer position can be used to manipulate the azimuthal orientation of the helices parallel to or tilted by an angle of 45 degrees with respect to the dipping direction in the transferred films. The study of the azimuthal order for the LB monolayers of PLGA-b-PMLGSLGs of various block lengths revealed that the observed effect arises mainly from the deformation of the PMLGSLG top brush layer, induced by the flow orientation around the transfer region. In those cases where the PMLGSLG block is tilted by a sufficiently large angle with respect to the surface normal, high azimuthal order parameters of 0.5-0.75 were obtained.
使用偏振传输傅里叶变换红外光谱研究了刚性棒状两亲性嵌段多肽（聚（α- L-谷氨酸）（PLGA）和聚（γ-甲基-L-谷氨酸-ran-γ-硬脂酰-L-谷氨酸）的 Langmuir-Blodgett（LB）单层中的方位螺旋取向（PMLGSLG），其中硬脂基取代基的摩尔分数为 30%。相对于前一次转移位置的浸渍相对位置可用于操纵螺旋相对于浸渍方向平行或倾斜 45 度的方位取向在转移膜中。对不同链段长度的 PLGA-b-PMLGSLG 的 LB 单层的方位有序性的研究表明，观察到的效应主要来自于转移区域周围的流动取向引起的 PMLGSLG 顶部刷层的变形。在 PMLGSLG 块相对于表面法线倾斜足够大角度的情况下，获得了 0.5-0.75 的高方位序参数。
