SiC Base Micro Sphere Synthesis Using Phase Separation Structures of Resin -Alkoxide Hybrid Precursors

提出的研究项目旨在控制由Si、C、O元素连续波动的非均相前驱体制备的碳化硅基陶瓷材料的形貌和性能。首先，将碳源(酚醛树脂和炭黑)与硅源(金属醇盐和硅树脂，陶瓷产量高)结合在一起。研究了剪裁前驱体的结构和前驱体高温热处理时碳化硅颗粒的形成过程。在酚醛树脂的情况下，前驱体中形成了相分离模式，这取决于树脂的粘度和凝胶化条件-所形成的碳化硅颗粒的形态反映了这种相分离模式(J.Appl Potnn Sci，94,1612-1618(2004))。在炭黑利用的情况下，生成的碳化硅的增加也反映了用过的炭黑的原始尺寸。然而，在前驱体中观察到的碳黑聚集的网络结构，…更多的碳化硅颗粒没有在形成的碳化硅颗粒中得到反映。在使用有机硅树脂的情况下，与使用硅醇盐相比，可以获得高的碳化硅产量(J.Ceram.SOC Japan，116,121-125(2008))。其次，详细研究了商品化的碳化硅颗粒-聚碳硅烷-木质部混合物的碳化硅浆料的粘弹性性质，这有望与碳化硅颗粒的形态有很深的关系(J.Ceram Soc Japan，115,982-986(2007))。在纳米碳化硅颗粒的情况下，发现了剪切速率与颗粒取向的关系。对于基质浸渍和涂层应用来说，浆料制备是至关重要的注意事项。第三，研究了聚碳硅烷与硅油的聚合物共混体系作为熔融可纺前驱体。熔融纺丝后，可观察到纤维的相分离模式。对于像连续中空纤维一样实现形态控制，聚合物熔体中的氢气饱和度将是决定连续孔狭窄的重要因素。Mater，352，69-72(2007))。较少

Proposed research project has aimed at control of morphology and properties of SiC based ceramic materials derived from heterogeneous precursors in which Si, C, O elements are located with continuous undulation in concentration. First, carbon sources (phenolic resins and carbon blacks) were combined with silicon sources (metal alkoxides and silicone resins with high ceramic yields). Structure of tailored precursors and SiC particle formation process at high temperature heat treatment from precursors were investigated. In the case of phenolic resins, phase separation patterns were formed in the precursors, which depend on the resin viscosity and gelation condition_ Morphology of formed SiC particles reflected such phase separation pattern(J.Appl Potnn Sci, 94, 1612-1618 (2004) ). In the case of carbon black utilization, the rise of the formed SiC also reflected primitive size of the used carbon black. Network structure of the carbon black aggregation observed in the precursors, however, … More was not reflected in the formed SiC particles. In the case of silicone resin utilization, high SiC yield can be achieved as compared with the utilization of Si alkoxide (J. Ceram. .Soc Japan, 116, 121-125 (2008) ). Secondary, viscoelastic properties of SiC slurries of commercialized SiC particles - polycarbosilane -xylem mixtures were investigated in detail, which is expected to have deep relationship with morphology of SiC particles (J. Ceram Soc Japan, 115, 982-986 (2007)). The relationship between shear rate dependence on particle orientation was found in the case of SiC nano particles. It is critically important notice about slurry preparation for matrix impregnation and coating applications. Thirdly, polymer blend systems of polycarbosilane and silicone oil were investigated as melt spinnable precursors. After the melt spinning, phase separation patterns were observed in spun fibers. For achievement of morphology control like continuous hollow fibers, hydrogen gas saturation in the polymer melts would be important factor, which determine the con tenuous pore strictures (lay Eng. Mater, 352, 69-72 (2007)). Less