RT info:eu-repo/semantics/article
T1 The effects of silica aerogel on the rheological behaviour and polymer matrix structure of Rigid Polyurethane foams
A1 Cimavilla Román, Paula
A1 Pérez Tamarit, Saúl
A1 Vananroye, Anja
A1 Moldenaers, Paula
A1 Rodríguez Pérez, Miguel Ángel
K1 Polyurethane foams
K1 Espumas de poliuretano
K1 Silica aerogel
K1 Aerogel de sílice
K1 Rheology
K1 Reología
AB The incorporation of silica aerogel particles into the isocyanate used to prepare Rigid Polyurethane composite foams drastically modifies its rheological behaviour. The isocyanate changes from being a Newtonian fluid of constant viscosity (0.3 Pa s at 25 °C) to a non-linear power-law material with complex viscosity decreasing from 104 to 101 Pa s with a slope −1 versus frequency. The change in response is caused by the formation of a percolated network of particles at contents above 2.5 wt% of aerogel. Moreover, the addition of aerogel significantly slows down the modulus-build up kinetics and vitrification of the matrix by approximately 4.5 min with every 1 wt% of aerogel added. For the foam with 3.0 wt% of aerogel, the combination of high viscosity at early reaction times coupled with the slow modulus build-up impedes the drainage which leads to a decrease in the fraction of material in the struts of the matrix.
PB Elsevier
SN 0014-3057
YR 2022
FD 2022
LK https://uvadoc.uva.es/handle/10324/54132
UL https://uvadoc.uva.es/handle/10324/54132
LA eng
NO European Polymer Journal, 2022, vol. 176, 111398
NO Producción Científica
DS UVaDOC
RD 27-dic-2024