Institute of Fine Chemistry and Nanochemistry, Department of Physical Chemistry and Applied Thermodynamics, University of Córdoba, Campus Universitario de Rabanales, Edificio Marie Curie, Córdoba E-14014, Spain.
Sorbonne Universités, UPMC Univ Paris 06, CNRS-UMR 7588, Institut des NanoSciences de Paris, F-75005 Paris, France; Synchrotron SOLEIL L'Orme des Merisiers Saint-Aubin, BP48 91192, Gif/Yvette Cedex, France.
J Colloid Interface Sci. 2017 Dec 15;508:583-590. doi: 10.1016/j.jcis.2017.08.069. Epub 2017 Aug 22.
Mixed Langmuir monolayers of 10,12-Pentacosadiynoic acid (DA) monomer and an amphiphilic Hemicyanine dye derivative have been formed at the air/water interface. Two derivatives of docosylpyridinium have been used, with either one included in the monolayer in 1:1molar ratio. The DA monomers within the mixed monolayers have been polymerized in situ at the air/water interface. The crystalline structure of the monolayer and the kinetics of polymerization have been probed by grazing incidence X-ray diffraction (GIXD). The polymerization of DA proceeds with no phase segregation, exclusively leading to the red polydiacetylene form. The kinetics of polymerization at the air/water interface has been monitored in situ by GIXD. The experimental results have been combined with Molecular Mechanics computer simulations, revealing that DA molecules are sequentially arranged with molecules of Hemicyanine dye in alternating rows. The hydrophobic chains of the dye molecules act as spacers between the DA monomers. Surprisingly, such molecular arrangement does not hinder the in situ photopolymerization of DA. The mechanism of polymerization of DA within the mixed Langmuir monolayers has been convincingly described in molecular detail. This approach for interfacial polymerization of DA holds great potential for optically active devices and nanostructures comprising self-assembled thin films based in polydiacetylene.
在空气/水界面形成了 10,12-二十五碳二炔酸（DA）单体和两亲半花青染料衍生物的混合 Langmuir 单层。使用了两种二十二烷基吡啶鎓衍生物，其中一种以 1:1 的摩尔比包含在单层中。在空气/水界面原位聚合混合单层中的 DA 单体。使用掠入射 X 射线衍射（GIXD）探测了单层的晶体结构和聚合动力学。DA 的聚合没有相分离，仅导致红色聚二乙炔形式。通过 GIXD 原位监测了空气/水界面上的聚合动力学。实验结果与分子力学计算机模拟相结合，表明 DA 分子与半花青染料分子在交替行中顺序排列。染料分子的疏水链作为 DA 单体之间的间隔物。令人惊讶的是，这种分子排列不会阻碍 DA 的原位光聚合。混合 Langmuir 单层中 DA 聚合的机制在分子细节上得到了令人信服的描述。这种 DA 的界面聚合方法在基于聚二乙炔的自组装薄膜的光学活性器件和纳米结构方面具有很大的潜力。
