Monomer stabilization silane

Styrene monomer was also copolymerized with a series of functional monomers by using a single-step dispersion copolymerization procedure carried out in ethanol as the dispersion medium by using azobisizobu-tyronitrile and polyvinylpyrollidone as the initiator and the stabilizer, respectively [84]. The comonomers were methyl methacrylate, hydroxyethyl acrylate, metha-crylic acid, acrylamide, allyltrietoxyl silane, vinyl poly-dimethylsiloxane, vinylsilacrown, and dimethylamino-... 

Vinylsilane monomers do not homopolymerize owing to steric inhibition within a required catalytic intermediate, yet will specifically copolymerize with an unhindered diene, resulting in isolated units of the vinylsilane within the copolymer. AUyhc silanes, however, show no resistance to homometathesis and yield novel high molecular weight, unsaturated polycarbosilanes with low glass transition temperatures and good thermal stability. 

In addition, VTMS hydrolyzes to a much eater extent than MTMS, an expected pattern similar to the /sopropoxy examples. Clearly the bulk of the Mopropoxy groups on the hindered silanes is very beneficial in protecting the silane from premature reaction during latex polymerization, when compared to the more traditional methoxy substituted silane monomers. This has implications for the ultimate properties of the final films, as the stability of the isopropoxy silanes allows levels of incorporation, and thus final performance, that are sinq)ly not available when using methoxy-substituted silane monomers. 

The bulk of the isopropoxy groups on the vinyl and methacryl silanes is unique among silane monomers in that, through their enhanced stability, levels of incorporation of silane an order of magnitude greater than standard methoxy-substituted monomers is possible. Thus, much higher performance can be achieved using these silane monomers. 

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