Melt Spinnable Blend Polymers of Polycarbosilane and Polysiloxane for Synthesis of Silicon Carbide Micro Tube Structures

Abstract

Silicon carbide base ceramic tubes were synthesized from blend polymers of polycarbosilane (PCS) and methylhydrogen silicon oil (H-oil) by polymer precursor method. This precursor method consisted of melt spinning, thermal oxidation curing and pyrolysis processes. Pore structure observed at cross sections of obtained tubes depended on H-oil content, melt-spinning temperature and oxidation curing conditions. At 578K for melt-spinning, however, a considerable amount of H-oil was decomposed during the spinning process. The resulting H-oil contents were usually lower than the starting H-oil contents. In the case of the 578K melt spinning, however, unique single pore structures were often observed in the tubes by adjusting the curing conditions. At 40% of the H-oil content, large pores with thin walls were observed at the cross-section, while such structures were difficult to be controlled. By reducing the melt-spinning temperature to 543K, the starting H-oil contents could be maintained during the spinning process. The cross sections of the tubes often showed multi pores in this case.