Formation of Bioactive Ceramic Foams by Polymer Pyrolysis and Self-Blowing

Abstract

Formation and characterization of hydroxyapatite-based porous ceramics derived from polymer pyroysis were investigated. Polymer based process is chosen for preparing porous hydroxyapatite-based ceramics having a high mechanical strength. The hydroxyapatite-based porous ceramic was prepared by a self-blowing process of a polymethylsiloxane with filler and pyrolyzed at above 1000 o C. Biphasic material consisted of hydroxyapatite and CaO has been prepared by solid state reaction from calcium hydroxide(Ca(OH) 2) and calcium hydrogen phosphate dihydrate(CaHPO 4 •2H 2 O) as a filler material. The influence of filler content on mechanical properties was evaluated. The change of crystalline phase, microstructure and mechanical properties were investigated and discussed.

A Morphological Study on the Titanium-Oxide Foams Processed Using Freeze-Casting

“…다공성 구조체는 높은 기공률과 큰 표면적을 갖는 특 징으로 분리막, 촉매 지지대, 흡수재, 생체-보철 임플란트 및 경량 구조 재료로 널리 이용되고 있다. [1][2][3][4] 특히 적절한 기공 크기와 기공률을 갖는 다공성 세라믹은 낮은 밀도 와 열전도도, 고온에서의 안정성, 화학적 부식 저항성, 낮 은 유전상수 등 각각의 고유한 성질 때문에 기능성 소재 분야에서 많은 관심을 끌고 있다. [5][6][7] 이때 다공성 세라믹 의 내부 기공 크기, 기공 형태의 분포가 잘 통제되는 것 이 중요한데, 이는 특별한 적용 분야에 맞게 설계된 기능 을 적절히 수행 하는데 직접적인 관련이 있기 때문이다.…”

Flexural Strength of Polysiloxane-Derived Strontium-Doped SiOC Ceramics

“…ilicon oxycarbide ceramics, in which silicon, oxygen, and carbon are incorporated into an amorphous network structure, have attracted increasing attention, especially for processing ceramic foams, [1][2][3][4][5][6][7][8] coatings, and thin films for functional parts, [9][10][11] and synthesizing nano-sized SiC particles 12) and cost-effective long fibers, 13,14) due to their improved mechanical and chemical properties compared to amorphous SiO 2 . 15,16) However, because of the excessively large shrinkage and weight loss during the pyrolysis and densification of these ceramics, it is difficult to prepare dense, monolithic SiOC ceramics.…”

“…17) The filler-free SiOC ceramics developed and reported in the literature are mostly either porous or thin films. 4,8,10) There are limited studies on the flexural strength of dense, monolithic SiOC ceramics. Renlund and Prochazka 18) reported an average flexural strength of 385 ± 227 MPa in SiOC ceramics prepared by the pyrolysis of commercially available polysiloxane.…”