Resumo

FLORES, J. et al. Poly (methyl methacrylate) with high syndiotatic content obtained by microemulsion polymerization using different surfactants. Rev. Mex. Ing. Quím [online]. 2011, vol.10, n.1, pp.125-135. ISSN 1665-2738.

In this paper, we present the microemulsión polymerization of MMA in three components using different surfactants (DTAB, DTAC, SDS and AOT). Stable latices with particle sizes below 46 nm and polymer with high molecular weights (> 1 ×10⁶g/mol) were obtained. ¹K and ¹³C NMR spectra of poly(methyl methacrylate) indicate that polymer with an average syndiotactic configuration between 72 and 78% was obtained; these values are larger than those reported for commercial PMMA. These results are interpreted on the basis that due to the small size of the particles (18 to 45 nm), chain growth takes place in a confined space. As a result of the higher syndiotactic content, the glass transition temperature increased. On the grounds that Tg is increased, the polymers obtained by microemulsión polymerization can be used at higher temperature than the commercial polymers. The structure and/or the electrostatic charge of the surfactant did not affect the extent of syndiotactic configuration.

Palavras-chave : methyl methacrylate; syndiotactic; microemulsion polymerization.

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