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The behaviour of poly(dimethylsiloxane-co-diphenylsiloxane)s in good and theta solvents

Domenii publicaţii > Chimie + Tipuri publicaţii > Articol în revistã ştiinţificã

Autori: Morariu S., Brunchi C.E., Cazacu M., Bercea M

Editorial: ACS Publications, Journal of Chemical & Engineering Data, 56, p.1468-1475, 2011.

Rezumat:

n this work, we investigated the behavior of poly(dimethylsiloxane-co-diphenylsiloxane)s under good and theta solvent conditions by using turbidimetry and viscosimetry. The evolution of the optical properties as a function of the solvent quality allowed the composition of the methylbenzene/methanol mixtures at the theta point to be determined. The intrinsic viscosity was determined in good (methylbenzene) and theta (methylbenzene/methanol) solvents at T = 298 K using different approaches. The unperturbed dimension parameters were calculated and are discussed as a function of copolymer composition. The introduction of the diphenylsiloxane units into a poly(dimethylsiloxane) chain results in an increase in the unperturbed dimensions as a consequence of the decrease in chain flexibility.

Cuvinte cheie: poly(dimethylsiloxane-co-diphenylsiloxane), theta point, unperturbed dimensions

URL: http://pubs.acs.org/doi/abs/10.1021/je1011778