Methacrylate Silatrane: New Building Block for Development of Functional Polymeric Coatings through Controlled Silanization

Abstract

Organosilicons are prevalent for the development of nanostructures, adhesives, fillers, and surface functionalization due to their ease of operation, availability, and effective modification on various surfaces. 3-(Trimethoxysilyl) propyl methacrylate (TMSPMA) is a widely used commercial silane for designing hybrid polymers via radical polymerization for a wide spectrum of applications. However, the chemical stability and processibility of TMSPMA encounter burdens due to its susceptibility to hydrolysis and aggregation, resulting in limiting its functionality and implementations. In this work, methylacrylate silatrane (MAST) was newly developed to bear a chemically stable tricyclic caged silatranyl ring and a transannular N → Si dative bond for excellent stability, processability, and progressive deposition. A complete, uniform, and thin assembled adlayer of MAST on a silicon wafer was verified by a contact angle goniometer, ellipsometry, atomic force microscopy, X-ray photoelectron microscopy, and Fourier transform infrared spectroscopy. The good homogeneity and molecular orientation of the MAST coatings are attributed to controlled silanization on oxide surfaces and strong intermolecular hydrogen bonds between internal urea groups. Moreover, the zwitterionic monomer of 2-methacryloyloxyethyl phosphorylcholine (MPC) was employed to copolymerize with MAST or TMSPMA to afford macromolecular modifiers of p(MPC9-co-MAST1) and p(MPC9-co-TMSPMA1), respectively, for surface modification and antifouling properties on silicon substrates. p(MPC9-co-MAST1) well preserved the reactivity of the silatrane groups after the polymerization process, whereas the hydrolysis of silane groups of p(MPC9-co-TMSPMA1) obviously occurred, giving rise to aggregation of polymer chains. Therefore, the p(MPC9-co-MAST1) film on surfaces exhibited superior wettability, grafting density, and antifouling properties compared to p(MPC9-co-TMSPMA1). Accordingly, we envision the great potential of the MAST building block for the development of functional hybrid polymers, well-defined polymeric thin films, and nanomaterials.

Silatrane-Based Molecular Nanolayers as Efficient Diffusion Barriers for Cu/SiO2/Si Heterojunctions: Implications for Integrated Circuit Manufacturing

“…In this study, a newly emerging pentacoordinate silicon compound, called silatrane, was used to construct a dense and robust diffusion barrier for Cu/SiO 2 /Si heterojunctions. The molecular structures of silatranes are analogous to those of silanes except that the open-chained alkoxy groups are replaced by a tricyclic caged structure with a transannular N → Si dative bond. − Due to the high structural stability of tricyclic cages, the risk of hydrolysis-driven self-polymerization of silatranes in solution is greatly reduced. Hydrolysis and condensation of the silatrane molecules are initiated when they contact the hydroxy groups on the SiO 2 surface, which is referred to as “controlled silanization”. , The controlled silanization facilitates the formation of well-oriented and highly packed organosilicon thin films.…”

Noncovalent Interactions of Silatranes and Germatranes with the Surface of Stoichiometric and Hydroxylated 2D Silica

“…The bonding degree with a surface and the surface density of functional groups can be determined quantitatively with the use of UV spectroscopy, if these groups have the fragments with high molar extinction coefficients, 12 as well as FTIR spectroscopy, by estimation of the changes in vibrations of grafted organic groups. 13 In addition, the characteristics of grafted layers are determined by obtaining AFM images 14 and XPS spectroscopy of the surface. It is worth noting the possibility of the use of the thermal desorption spectroscopy (TDS) technique to determine the molecules that are not yet immobilized on the surface, but physically adsorbed on it, 15 including the 2D silicatene as such a surface.…”

Antifouling Coatings from Glassy Polyelectrolyte Complex Films

“…The antifouling properties of zwitterions were initially directed toward biomedical applications, such as preventing protein and bacterial adhesion in vivo. Zwitterionic polymer brushes may be grafted to, , or grafted from, , surfaces. Zwitterion brushes grown from surfaces have been extensively reported by Jiang’s group. ,, These coatings demonstrated particularly effective fouling resistance, even from pure serum.…”

“…In this work, we present a new class of glassy , rugged coatings from complexed polyelectrolytes, which proved counterintuitively effective at preventing fouling by Chlamydomonas reinhardtii, native to aquatic environments. , C. reinhardtii is a eukaryotic unicellular green microalga possessing two flagella . Commonly found growing in freshwater and soil, it is a suitable model fouling organism in freshwater aquatic environments. , The films were prepared with sulfonated poly­(ether ether ketone), a widely used “engineering polymer” with a stiff hydrophobic backbone.…”