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Influence of Gas-Flow Conditions on the Evolution of Thermally Insulating Si3N4 Nano-Felts.

ABSTRACT: This paper discusses the role of nitrogen (N2) gas flow conditions on the formation of silicon nitride (Si3N4) nano-felts from polysiloxane-impregnated polyurethane (PU) foams. The polymeric foam was converted into an amorphous silicon oxycarbide (SiOC) artefact during pyrolysis, which was then transformed, at a higher temperature, into a Si3N4 felt through a reaction between the decomposition products of SiOC with N2. The study identified that a N2 flux of ~2.60 cm.min-1 at the cross-section of the furnace (controlled to 100 cm3.min-1 at the inlet of the furnace using a flowmeter) substantially favored the transformation of the parent SiOC foam to Si3N4 felts. This process intensification step significantly reduced the wastage and the energy requirement while considering the material production on a bulk scale. The study also inferred that the cell sizes of the initial PU templates influenced the foam to felt transformation.

SUBMITTER: Santhosh B

PROVIDER: S-EPMC8839865 | biostudies-literature | 2022 Jan

REPOSITORIES: biostudies-literature

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Influence of Gas-Flow Conditions on the Evolution of Thermally Insulating Si3N4 Nano-Felts.

Santhosh Balanand B Biesuz Mattia M Zambotti Andrea A Sorarù Gian Domenico GD

Materials (Basel, Switzerland) 20220129 3

This paper discusses the role of nitrogen (N2) gas flow conditions on the formation of silicon nitride (Si3N4) nano-felts from polysiloxane-impregnated polyurethane (PU) foams. The polymeric foam was converted into an amorphous silicon oxycarbide (SiOC) artefact during pyrolysis, which was then transformed, at a higher temperature, into a Si3N4 felt through a reaction between the decomposition products of SiOC with N2. The study i ...[more]

PMID: 35161013

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