INVESTIGADORES
PETTARIN Valeria
congresos y reuniones científicas
Título:
The yielding of propylene polymers
Autor/es:
LAURA FASCE; VALERIA PETTARIN; PATRICIA FRONTINI; CLAUDIA MARANO; MARTA RINK
Lugar:
Cincinnatti, Ohio, USA
Reunión:
Conferencia; Annual Technical Conference of the Society of Plastics Engineers ANTEC 2007; 2007
Resumen:
The use of toughened propylene-based polymers in
engineering applications has increased the demand for
relevant data regarding yielding behavior in complex
stress states. Through this work the yield behavior of
polypropylene homopolymer, polypropylene copolymers
and polypropylene elastomeric polyethylene mechanical
blends was studied. This investigation proves that
Modified Von Mises criterion provides reasonable
predictions of the biaxial macroscopic yield behavior of
these materials despite the inherent tendency of PP to
deform by crazing. The incorporation of a second
elastomeric-phase by melt blending or increasing
crystallinity does not change the pressure dependency of
PP polymers. The studied copolymers exhibited a more
pronounced yield stress sensitivity to hydrostatic pressure
than homopolymers and mechanical blends. Yielding
envelopes decrease with increasing elastomer content in
mechanical blends and enlarge with increasing
crystallinity.