INVESTIGADORES
SARMORIA Claudia
artículos
Título:
Modelling molecular weight changes induced in polydimethylsiloxane by gamma and electron beam irradiation
Autor/es:
SATTI, ANGEL J; ANDREUCETTI, NOEMÍ A; RESSIA, JORGE A; VALLAT, MARIE FRANCE; SARMORIA, CLAUDIA; VALLES, ENRIQUE M
Revista:
EUROPEAN POLYMER JOURNAL
Editorial:
Elsevier
Referencias:
Año: 2008 vol. 44 p. 1548 - 1555
ISSN:
0014-3057
Resumen:
A commercial
linear polydimethylsiloxane (PDMS) was subject to gamma irradiation under
vacuum and in air, as well as to accelerated electron beam radiolysis (EB). All
irradiation treatments were done at room temperature. The molecular weight
changes induced by the radiation processes have been investigated using size
exclusion chromatography (SEC) with refraction index (RI) and multi angle laser
light scattering (MALLS) detectors to obtain the number and weight average
molecular weights of the irradiated samples.
The analysis of
the data indicates that crosslinking reactions predominated over scission
reactions in all cases. Gamma irradiation under vacuum was the most efficient
process within the analyzed dose range, reaching the gel point earlier.
Irradiation in the presence of oxygen induces oxidative effects, both in gamma
and EB irradiations. A previously developed mathematical model of the
irradiation process that accounts for simultaneous scission and crosslinking
and allows for both H and Y crosslinks fitted well the measured molecular
weight data.