Development of silica with structured morphology and the reinforcement property as a filler for rubber

Research Project

Project/Area Number	08650803
Research Category	Grant-in-Aid for Scientific Research (C)
Allocation Type	Single-year Grants
Section	一般
Research Field	Composite materials/Physical properties
Research Institution	Kinki University
Principal Investigator	IHARA Tatsuhiko Kinki University, Industrial Chemistry Professor, 工学部, 教授 (50133541)
Project Period (FY)	1996 – 1997
Project Status	Completed (Fiscal Year 1997)
Budget Amount *help	¥2,100,000 (Direct Cost: ¥2,100,000) Fiscal Year 1997: ¥500,000 (Direct Cost: ¥500,000) Fiscal Year 1996: ¥1,600,000 (Direct Cost: ¥1,600,000)
Keywords	carbon black / tetraethoxysilane / silica coating / water vapor plasma / reinforcement property for rubber / ゴム補強性
Research Abstract	In order to develop the titled material, that is carbon black (Si-CB) having chain-like appearance of CB agglomerates structure with surface property of silica, was prepared by two methods using tetraethoxysilane (TEOS) and carbon black on which hydroxyl groups were introduced by water vapor plasma treatment (Hy-CB), one is wet method based on sol-gel process and the other is dry method called gas phase layer-by-layer adsorption method. In the wet method, Hy-CB reacted with TEOS in an aqueous suspension without addition of catalyst. Silica layer was formed by the dehydration-polymerization reaction followed by the hydrolysis of TEOS.Viscosity data during coating process in the suspension showed the progress of coating with the increase of reaction time, It was found that the surface of the CB was uniformly coated by the silica layer with the thickness of about 1.5 nm. In the dry process, Hy-CB was reacted with TEOS by a gas phase layer-by-layer adsorption method. The process consists of 4 process including 1) gas phase adsorption process of TEOS onto Hy-CB, 2) evacuation process of physically adsorbed TEOS, 3) hydrolysis and activation process by the contact with ammonia vapor, 4) evacuation process of ammonia. It was found that the controlling of the thickness of the silica layer formed on the Hy-CB is possible in a nano-scale by repeating these sequence process. The wet property and wear properly was much improved when these new materials were applied as a reinforcing material for the rubber compared to ordinary one which was prepared by just mixing a silica in it.