INTEC   05402
INSTITUTO DE DESARROLLO TECNOLOGICO PARA LA INDUSTRIA QUIMICA
Unidad Ejecutora - UE
artículos
Título:
Emulsion Polymerization of Isoprene. Estimatiion of the Branching Exponent with the Help of a Mathematical Model
Autor/es:
MINARI, R. J.; RODRIGUEZ, V. I.; ESTENOZ, D. A.; VEGA, J. R.; MEIRA, G. R.; GUGLIOTTA, L. M.
Revista:
JOURNAL OF APPLIED POLYMER SCIENCE
Editorial:
JOHN WILEY & SONS INC
Referencias:
Año: 2009
ISSN:
0021-8995
Resumen:
This work investigates a batch and unseeded emulsion polymerization of isoprene at 10 ºC with n-dodecylmercaptan as chain transfer agent (CTA). The obtained polyisoprene (PI) was analyzed by size exclusion chromatography (SEC) with on-line viscometry. A global polymerization model was adjusted to the measurements of conversion, average particle size, and average molecular weights. The CTA concentration strongly affects the average molecular weights, but has a negligible effect on conversion, average particle diameter, and average branching. Due to the combined effects of chain transfers to the polymer and to the CTA, the final molar mass distributions exhibited dispersity indexes higher than 10. The polymerization model predictions on the average degree of branching was combined with an ideal SEC model for adjusting the branching exponent of PI in tetrahydrofuran at 25 ºC, that resulted e = 2.5. A sensitivity analysis showed that +20% errors in  induced variations in e lower than -10%.