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Wollastonite Foams From an Extruded Preceramic Polymer Mixed with CaCO 3 Microparticles Assisted by Supercritical Carbon Dioxide
Author(s) -
Bernardo Enrico,
Parcianello Giulio,
Colombo Paolo,
Matthews Siobhan
Publication year - 2013
Publication title -
advanced engineering materials
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.938
H-Index - 114
eISSN - 1527-2648
pISSN - 1438-1656
DOI - 10.1002/adem.201200202
Subject(s) - wollastonite , materials science , supercritical carbon dioxide , extrusion , porosity , supercritical fluid , silicone , polymer , mixing (physics) , composite material , chemical engineering , carbon dioxide , organic chemistry , raw material , chemistry , physics , quantum mechanics , engineering
Wollastonite (CaSiO 3 ) bioceramics have recently received great attention as hard tissue repairing material. In this paper we discuss a novel processing for open cell foams based on the mixing of a silicone resin with CaCO 3 micron‐sized fillers, by means of conventional polymer extrusion assisted by supercritical carbon dioxide. The novel mixing was so effective that the wollastonite yield was comparable to that achieved employing much more reactive nanosized fillers, and led to silicone/CaCO 3 extruded parts, embedding CO 2 . These parts can be easily converted into highly porous foams (porosity of about 80%) by a secondary low temperature treatment, before final ceramization at 900 °C. Depending on the conditions of secondary treatment, it was possible to obtain foams with similar density but different pore architecture, and consequently different strength, ranging from 0.45 to 6 MPa.