화학공학소재연구정보센터
홈 로그인 로그아웃 연락처 사이트맵
HWAHAK KONGHAK, Vol.41, No.4, 509-516, August, 2003
Export Citation
혼합용매법에 의한 Mullite 전미분체 생성기구에 관한 연구
The Formation Mechanism of Pre-Mullite Particles by the Mixed Solvents Method
황운연†, 이정운, 박형상, 김용렬1, 구기갑
  • 서강대학교 화학공학과, 121-742 서울시 마포구 신수동 1
  • 1대진대학교 화학공학과, 4887-711 경기도 포천군 포천읍 선단리 11-1
Un-Yeon Hwangn†, Jung-Woon Lee, Hyung-Sang Park, Yong-Ryul Kim1, and Kee-Kahb Koo
  • Department of Chemical Engineering, Sogang University, 1 Sinsu-dong, Mapo-gu, Seoul 121-742, Korea
  • 1Department of Chemical Engineering, DaeJin University, 11-1 Sondan-ri, Poch´on-up, Poch´on-gun, Kyonggi 487-711, Korea
E-mail:
초록
Si-와 Al-알콕시드의 반응속도 차이를 조절하기 위한 부분 가수분해법과 입자 형태를 제조하기 위한 혼합용매법을 이용하여 구형의 미세한 mullite 전미분체를 제조하였다. Mie 이론을 적용시켜 반응시간에 따른 반응용액의 탁도 및 입자 수밀도의 변화를 측정하여 혼합용매법에 의한 입자 생성기구에 대하여 고찰하였다. 알콕시드와 옥탄을 용액에 아세토니트릴을 첨가하면 알콕시드의 용해도가 낮아지고 따라서 알콕시드의 일부가 액적을 형성하며, 액적은 안정화제 (HPC)에 의하여 구형을 유지하게 된다. 그리고 가수분해 및 축합중합 반응에 의하여 액적의 입자 크기는 감소하며, 동시에 혼합용액에 용해되어 있던 알콕시의 가수 분해 및 축합중합 반응에 의하여 미세 입자가 생성된다. 액적형태로 생성된 큰 입자와 미세 입자의 응집에 의하여 최종 입자가 생성되었다.
In this study, spherical fine pre-mullite particles were prepared by partial hydrolysis method to control the reaction rate difference of two alkoxides, and by mixed solvent method to control the particle shape. Based on the adaptation of Mie theory, the formation mechanism of pre-mullite particle in alkoxide-octanol-acetonitrile system has been investigated by measuring of the turbidity of solution, the number density and the size of the particles during the reaction. As the acetonitrile was added in the alkoxide-octanol solution, the solubility of the alkoxide decreased. A part of alkoxide was segregated from solution in the form of droplets, whereas the rest of the alkoxide existed as dissolved state in octanol. The droplets are stabilized with stabilizer (HPC). In the next step, hydrolysis and condensation reactions of the alkoxide droplets decrease the size of droplets and, at the same time, fine particles are formed from the alkoxide dissolved in octanol. Subsequently, the final particles are produced by aggregation between the large particles through the droplet form and the fine particles.
Keywords:Mullite;Sol-Gel Process;Mixed Solvent;Partial Hydrolysis;Emulsion;Metal Alkoxide;Mie Theory
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