ITPN   24979
INSTITUTO DE TECNOLOGIA EN POLIMEROS Y NANOTECNOLOGIA
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Improving physical crosslinking of silica polyurethane bio-based nanocomposites by grafting methods
Autor/es:
LEONEL MATIAS CHIACCHIARELLI; I. PURI; M. RALLINI; A. VAZQUEZ; J. M. KENNY; L. TORRE
Reunión:
Conferencia; 4th International Conference on Biodegradable and Biobased Polymers; 2013
Resumen:
Silica nanoparticles (SN) were grafted with
caprolactone using an environmentally friendly approach. Grafted nanoparticles
(GN) with organic weight fractions (wof)
in the range 0-46 wt.% were synthesized. The GNs were used to prepare bio-based
polyurethane (PU) nanocomposites. Transmission Electron Micrographs (TEM)
corroborated that the GNs interfacial area with the PU increased by the
reduction of agglomerate dimensions from 10mm to around 100nm. Dynamic
Mechanical Analysis, Differential Scanning Calorimetry (DSC), X-Ray
Diffraction, TGA and Tensile tests were used to evaluate the effect of changing
wof and filler
concentration on the nanocomposite properties. At low wof (<15%), the GNs improved Elastic Modulus,
Strength and Ductility. The thermal stability of the GN based PU nanocomposites
was improved, mainly by increasing the stability of the castor oil based soft
segments. The nanoindenter technique was able to resolve how the filler changed
the hard and soft segment regions.