Layered assembly of alkoxy-substituted bis(trichlorosilanes) containing various organic bridges via hydrolysis of Si–Cl groups
作者:Yasuhiro Fujimoto、Masaru Heishi、Atsushi Shimojima、Kazuyuki Kuroda
DOI:10.1039/b512482d
日期:——
Monoalkoxy derivatives of bis(trichlorosilanes) containing methylene, ethylene, and phenylene bridges (Cl3SiâRâ²âSiCl2OC16H33, Râ²
=
âCH2â, âC2H4â, âC6H4â) were synthesized and self-assembly of the amphiphilic hydrolyzed species ((HO)3SiâRâ²âSi(OH)2OC16H33) was investigated. Hydrolysis of all SiâCl groups was confirmed by liquid-state 29Si and 13C NMR while the alkoxy groups were retained. The self-assembly was induced either by casting the hydrolyzed solutions on glass substrates or by cooling. The structures of the products were characterized by X-ray diffraction (XRD), electron microscopies (TEM and SEM), and solid-state 29Si and 13C NMR. The products obtained from methylene- and ethylene-bridged monomers have lamellar structures consisting of bridged polysilsesquioxane layers and all-trans hexadecanol layers, which means that alkoxy groups were cleaved during polycondensation. The large difference in the d values of these hybrids (5.84 nm and 3.40 nm) suggests the variation in the arrangement of hexadecanol molecules within the layers. In contrast, the phenylene-bridged monomer afforded a lamellar solid (d
= 5.14 nm) consisting of monomeric species, where both silanol groups and alkoxy groups mostly remain intact. This is attributed to the relatively stronger interaction and hydrogen-bonding networks between hydrolyzed species.
含有亚甲基、亚乙基和亚苯基桥的双(三氯硅烷)的单烷氧基衍生物(Cl3Si→R→SiCl2OC16H33、R→2
=
合成了-CH2-、-C2H4-、-C6H4-),并自组装了两亲性水解物质((HO)3Si-R-2-Si(OH)2OC16H33)被调查。通过液态 29Si 和 13C NMR 证实了所有 Si-Cl 基团的水解,同时保留了烷氧基。通过将水解溶液浇注在玻璃基板上或通过冷却来诱导自组装。通过X射线衍射(XRD)、电子显微镜(TEM和SEM)以及固态29Si和13C NMR对产物的结构进行了表征。由亚甲基和亚乙基桥联单体获得的产物具有由桥联聚倍半硅氧烷层和全反式十六醇层组成的层状结构,这意味着烷氧基在缩聚过程中被裂解。这些杂化物的 d 值(5.84 nm 和 3.40 nm)的巨大差异表明层内十六醇分子排列的变化。相反,亚苯基桥接单体提供了层状固体(d
= 5.14 nm)由单体组成,其中硅烷醇基团和烷氧基基团大多保持完整。这归因于水解物质之间相对较强的相互作用和氢键网络。