Silanes, comparison with carbon

This phenomenon may be one of the reasons of increasing of strength of composite in comparison with composites containing unmodified bentonite. The composites with modified bentonite display more high compatibility of the components than in case of same composites with unmodified filler. The modified filler has more strong contact with polymer matrix (thanks to silane modifier) than unmodified bentonite. Therefore mechanical stresses formed in composites by stretching or compressing forces are absorbed effectively by relatively soft silane phases, i.e. the development of micro defects in carbon chain polymer matrix of composite closes in silane part of the material. 

Abstract—The nature of the product of the reaction between an aminated silane and carbon dioxide was re-examined with the aid of simple model compounds, several amines, and several aminosilanes. Since the reaction products previously proposed include the amine bicarbonate and a carbamate derived from the amine, ammonium bicarbonate and ammonium carbamate were studied as models for the anions. Carbon dioxide adducts of neat model amines were prepared and studied. Results from a variety of techniques are summarized. Among the most useful was Fourier transform infrared (FTIR) spectroscopy of fluorolube mulls. FTIR spectra were distinctive and assignments characteristic of the two species were extracted from the spectral data. Comparisons of these assignments with the products of the reaction between carbon dioxide and various amines were made. The results indicate that alkylammonium carbamates are the principal product. Nuclear magnetic resonance (NMR) spectra in D20 indicated much dissociation and were not helpful in defining the products. 

NMR spectroscopy. In the olefinic region, only a single peak at 5.70 ppm (1 H) was observed. For comparison, the vinyl -CH of ( )-3-trimethylsilyl-3-octene is found at 5.60 ppm (9). Two nonequivalent vinyl carbons, as well as two distinct allylic carbons, were observed in the NMR spectrum. No peaks could be assigned to either 1,2 or 3,4 structures in either the or NMR spectra. Further, only a single silicon resonance was seen in the Si NMR spectrum. Finally, protodesilation of the polymer by treatment with HI yielded (Z)-l,4-poly(butadiene) (III), whose structure was confirmed by IR spectroscopy (8). Protodesilation of vinyl silanes occurs stereospecif-ically with retention of configuration (10, 11). The data are consistent with -11 (equation 1). 

For a comparison the interaction of the initiators 2,2-dimethoxy-2-phenylacetophenone (DMPA), (2-hydroxy-2-propyl)phenone la (bothnon-coreactive) and the epoxide If with silica was also investigated.Silica was treated with 0.5 weight equivalent of these compounds in the same manner as previously described for the silanes Id,e. Ihe resulting materials were analyzed by e.a. (Table III). The results of e.a. are primarily given as percent carbon because the structure of the organic species on silica is not absolutely clear (a trihydroxy compound is assumed as derivative of If). 

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