Foaming of polysiloxane resins with ethanol: A new route to pyrolytic macrocellular SiOC foams

Kód výsledku v IS VaVaI

RIV/00216208:11310/15:10315034 - isvavai.cz

Nalezeny alternativní kódy

RIV/68081723:_____/15:00447628 RIV/61389013:_____/15:00447628 RIV/67985891:_____/15:00447628

Výsledek na webu

http://dx.doi.org/10.1016/j.ceramint.2015.07.151

DOI - Digital Object Identifier

10.1016/j.ceramint.2015.07.151

Jazyk výsledku

angličtina

Název v původním jazyce

Foaming of polysiloxane resins with ethanol: A new route to pyrolytic macrocellular SiOC foams

Popis výsledku v původním jazyce

Polysiloxane foams as precursors to silicon oxycarbide (SiOC) foams were prepared via simultaneous cure and foaming of liquid methylsiloxane resins, using the relatively environment-friendly ethanol as blowing additive of the boiling-solvent-type, and concentrated aqueous ammonia as catalyst. In order to achieve foam regularity, siloxane-based surfactants were added, and bubble nucleation by mechanical stirring was performed. The precursor foams were subsequently pyrolysed in nitrogen at 1000 degrees C,yielding SiOC foams as end products. The properties of the latter were fine-tuned during the foaming of the precursors, by the amount of added ethanol and by the time of mechanical stirring prior to foaming. The so-obtained SiOC foams displayed densities of 0.17-0.42 g/cm(-3), corresponding to macro-porosities of 91-79%, compressive strength of 1-6 MPa, and elastic moduli of 0.2-1.6 GPa.

Název v anglickém jazyce

Foaming of polysiloxane resins with ethanol: A new route to pyrolytic macrocellular SiOC foams

Popis výsledku anglicky

Polysiloxane foams as precursors to silicon oxycarbide (SiOC) foams were prepared via simultaneous cure and foaming of liquid methylsiloxane resins, using the relatively environment-friendly ethanol as blowing additive of the boiling-solvent-type, and concentrated aqueous ammonia as catalyst. In order to achieve foam regularity, siloxane-based surfactants were added, and bubble nucleation by mechanical stirring was performed. The precursor foams were subsequently pyrolysed in nitrogen at 1000 degrees C,yielding SiOC foams as end products. The properties of the latter were fine-tuned during the foaming of the precursors, by the amount of added ethanol and by the time of mechanical stirring prior to foaming. The so-obtained SiOC foams displayed densities of 0.17-0.42 g/cm(-3), corresponding to macro-porosities of 91-79%, compressive strength of 1-6 MPa, and elastic moduli of 0.2-1.6 GPa.

Druh

J_x - Nezařazeno - Článek v odborném periodiku (Jimp, Jsc a Jost)

CEP obor

JI - Kompositní materiály

OECD FORD obor

—

Projekt

GAP107/12/2445: SiOC keramická pěna z pyrolyzovaného polymerního prekurzoru jako jádro tepelně odolných sendvičových struktur

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2015

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Ceramics International

ISSN

0272-8842

e-ISSN

—

Svazek periodika

41

Číslo periodika v rámci svazku

10

Stát vydavatele periodika

GB - Spojené království Velké Británie a Severního Irska

Počet stran výsledku

11

Strana od-do

13561-13571

Kód UT WoS článku

000362860900129

EID výsledku v databázi Scopus

2-s2.0-84939515640