INVESTIGADORES
QUINZANI Lidia Maria
artículos
Título:
Polyethylenes Modified by Irradiation and Organic Peroxide Treatment : Rheological Study
Autor/es:
CLAUDIO JAVIER PÉREZ; ENRIQUE M. VALLÉS; LIDIA MARÍA QUINZANI; MARCELO DANIEL FAILLA
Revista:
LATIN AMERICAN APPLIED RESEARCH
Editorial:
PLAPIQUI(UNS-CONICET)
Referencias:
Lugar: Bahia Blanca; Año: 2003 vol. 33 p. 109 - 114
ISSN:
0327-0793
Resumen:
A series of polyethylenes was obtained by modification of two commercial
high-density polyethylenes. The organic
peroxide concentrations and irradiation dosis used are below the critical ones
that produce molecular networks. The
molecular weights of the polymers increase, and the molecular weight
distribution gets wider, as the concentration/dose increases. These results are a consequence of the large
molecular weight molecules generated during the chain-linking modification
processes. By the time traces of gel
begin to appear in the samples, the peroxide modified materials display larger
molecular weights and smaller vinyl concentrations than the irradiated ones.
The rheological behavior of these materials is analyzed as a function of the molecular
structure of the polymers and the concentration/dose used in the modification
processes. All the modified polymers show a complex thermo-rheological
behavior associated to the presence of long-branched macromolecules. The peroxide treatment generates the polymers
with the largest rate of change of flow activation energy.