N-ALKYLSILOXANES - FROM SINGLE MONOLAYERS TO LAYERED CRYSTALS - THE FORMATION OF CRYSTALLINE POLYMERS FROM THE HYDROLYSIS OF N-OCTADECYLTRICHLOROSILANE

Formation of a new class of layered, microcrystalline polymers from a simple hydrolytic polycondensation of n-alkyltrichlorosilanes in water is demonstrated. The structure of the polymeric condensate, determine d from a combination of spectroscopic, diffraction, and thermal analys is techniques, consists of highly uniform, pillared microcrystallites in which the inorganic siloxy backbones are present in periodic layers , each containing a monomolecular layer of intercalated water, separat ed by crystalline assemblies of alkyl chains. The alkyl-chain organiza tion shows a remarkable resemblance to that in highly organized, self- assembled monolayers formed from the precursor silane molecules on hyd rophilic substrates and this parallel lends support to the critical im portance of water in monolayer self-assembly of silanes.