20 research outputs found
Temperature drop turbidimetry as a means for the rapid determination of the polydispersity of polymers ii polyethylene oxide
Temperature Drop Turbidimetry as a Means for the Rapid Determination of the Polydispersity of Polymers Part III. Polyethylene
Temperature drop turbidimetry as a means for the rapid determination of the polydispersities of polymers: Polystyrene
Study of the inhibition effect of stable iminoxy radicals on the oxidation degradation of polymers
Polyurethanes from 4,4?-diphenylmethane diisocyanate and poly(ethylene glycol)s. II. Crystallographic data, heats of melting and crystallization, thermal stability, crystallinity and density
Hydrophobic/hydrophilic P(VDF-TrFE)/PHEA polymer blend membranes
Polymer blend membranes have been obtained consisting of a hydrophilic and a hydrophobic polymers
distributed in co-continuous phases. In order to obtain stable membranes in aqueous environments,
the hydrophilic phase is formed by a poly(hydrohyethyl acrylate), PHEA, network while the
hydrophobic phase is formed by poly(vinylidene fluoride-co-trifluoroethylene) P(VDF-TrFE). To obtain
the composites, in a first stage, P(VDF-TrFE) is blended with poly(ethylene oxyde) (PEO), the latter used
as sacrificial porogen. P(VDF-TrFE)/PEO blend membranes were prepared by solvent casting at 70°
followed by cooling to room temperature. Then PEO is removed from the membrane by immersion in
water obtaining a P(VDF-TrFE) porous membrane. After removing of the PEO polymer, a P(VDF-TrFE)
membrane results in which pores are collapsed. Nevertheless the pores reopen when a mixture of
hydroxethyl acrylate (HEA) monomer, ethyleneglycol dimethacrylate (as crosslinker) and ethanol (as
diluent) is absorbed in the membrane and subsequent polymerization yields hybrid
hydrophilic/hydrophobic membranes with controlled porosity. The membranes are thus suitable for
lithium-ion battery separator membranes and/or biostable supports for cell culture in biomedical
applications.This work was funded by the Spanish Ministry
of Economy and Competitiveness (MINECO)
through the project MAT2013-46467-C4-1-R
(including the FEDER financial support). The
work of the Portuguese group was funded by
FEDER funds through the “Programa
Operacional Factores de Competitividade e
COMPETE” and by national funds fromFundação para a Ciência e a Tecnologia, in the
framework of the strategic project Strategic
Project PEST-C/FIS/UI607/2014. The authors
also thank funding from Matepro - Optimizing
Materials and Processes”, ref.NORTE-07-0124-
FEDER-000037”, co-funded by the “Programa
Operacional Regional do Norte” (ON.2 e O Novo
Norte), under the “Quadro de Referência
Estratégico Nacional” (QREN), through the
“Fundo Europeu de Desenvolvimento Regional”
(FEDER), and grant SFRH/BD/68499/2010
(C.M.C.)