CAJ | 학술논문

以超支化液态聚碳硅烷（LPCS）与固态聚碳硅烷（纯PCS）的共混物作先驱体,熔融纺丝;所得原丝再在热空气气氛中氧化交联,在高温氮气气氛中热裂解,得到碳化硅纤维。研究表明,15%（质量分数）LPCS的加入,可使纯PCS先驱体的纺丝温度,从285℃降低到225℃;纺丝性能和纤维表面质量明显提高;还可以提高氧化交联的效率,降低交联温度,从而减少纤维部分融并、粘结的弊端;虽然纤维的室温力学强度有所降低,但抗氧化性能提高,1400℃氧化交联后,力学性能几乎不变;而纯PCS的力学性能却降为原来的50%。
이초지화액태취탄규완（LPCS）여고태취탄규완（순PCS）적공혼물작선구체,용융방사;소득원사재재열공기기분중양화교련,재고온담기기분중열렬해,득도탄화규섬유。연구표명,15%（질량분수）LPCS적가입,가사순PCS선구체적방사온도,종285℃강저도225℃;방사성능화섬유표면질량명현제고;환가이제고양화교련적효솔,강저교련온도,종이감소섬유부분융병、점결적폐단;수연섬유적실온역학강도유소강저,단항양화성능제고,1400℃양화교련후,역학성능궤호불변;이순PCS적역학성능각강위원래적50%。
A highly branched liquid polycarbosilane （LPCS） was mixed with a solid polycarbosliane （PCS） to give a polymer blend. It was then melt-spun into precursor fibers, oxidation-curd in hot-air, and converted into silicon carbide fibers by pyrolysis under nitrogen. It was found that the addition of the LPCS resulted in a sig- nificant drop on the spinning temperature from 285℃ （solid PCS） to 225℃ （with 15% LPCS）, while the spin- ning ability and fiber＇s surface of the polymer blend was also markedly improved over the solid PCS. Further more, the LPCS enhanced the oxidation curing, reducing the curing temperature and hence the tendency for fi- ber partial melting and sticking. Although the strength of silicon carbide fibers decreased owing to the presence of the LPCS, the oxidation resistance was improved. The strength of fibers with LPCS maintained the same af- ter treatment in air in 1400℃, and the solid PCS fibers reduced to half the original.