Dacc Co., Ltd.

Korea Institute of Ceramic Engineering and Technology

Hong Sik Park

Hyun Kyu Shin

Kwang Soo Kim

Dong Won Lim

Dae Hyun Cho

Young Hee Kim

Hyung Rae Kim

Soo Ryong Kim

Doh Hyung Riu

Kyung Ja Kim

Woo Chul Choi

Jong Hyun Park

Dong Geun Shin

Sang Hyo Park

The present invention is related to a method of producing polycarbosilane by heating polydimethylsilane at low pressure within the range of 320&#x2dc;450&#xb0; C. using zeolite having the Si/Al or Si/B ratio of 1&#x2dc;200 as catalyst. This invention uses a zeolite with the structure of ZSM-5, ZSM-11, ZSM-12, zeolite X and zeolite Y, which has the Si/Al or Si/B ratio of 1&#x2dc;200, as catalyst. When polycarbosilane is produced using a specific zeolite as catalyst, Si/Al or Si/B ratio can be adjusted at any proportion, enabling acidity control of catalyst, and therefore the molecular weight of final products can be easily controlled and the product yield can be improved, compared to conventional solid acid catalysts.

Method of producing polycarbosilane using zeolite as catalyst

The present invention relates to a clutch for transmission power. The clutch for transmission power according to the present invention includes flywheel, clutch cover and clutch disk assembly positioning between the flywheel and the clutch cover; moreover, the clutch disk assembly includes a clutch facing having main body portion formed with a center hole in the middle thereof, and a contacting portion wherein one side thereof faces the friction pad at said flywheel side and the other side thereof faces the press plate of said clutch cover, and the portion facing each other between the friction pad and the press plate is made of carbon-carbon composition; a spline hub being overlapped with one side of the clutch facing wherein a spline groove is formed in the inner diameter thereof and a connecting means for connecting the clutch facing with the spline hub. Furthermore, the clutch disk assembly and the method of manufacturing the friction substance for clutch according to the invention can improve assemblability and reduce weight by simplifying it as a single part without using shock absorbing apparatus such as coil spring or the like on clutch disk assembly. In addition, the power transmission of an engine can be improved, and also it has an effect that an automobile can start softly and slippage does not occur even at abrupt acceleration by providing with carbon-carbon composition or carbon-silicon carbide composition having excellent shock absorption function.

Clutch for transmission of power

A method for manufacturing carbon-carbon composites includes steps of producing a mat using carbon fiber, carbon fabric, carbon sheet, or staple fiber; laminating at least three layers of mats; producing a preform using the laminated mats with a needle punching method; performing a first thermal treatment process on the produced preform at a predetermined temperature; densifying the first-thermal-treated preform; performing a second thermal treatment process on the densified preform; forming a predetermined shape out of the second-thermal-treated preform; and performing an oxidation resistant treatment process of the shaped preform.

Method for manufacturing carbon-carbon composites

Growing community of inventors

Kyungnam, South Korea

Hong Sik Park