摘要:
The invention relates to novel polymeric hydridochlorosilazanes, to their preparation, to their processing to form ceramic materials containing silicon nitride, and to said materials themselves. The polymeric hydridochlorosilazanes are prepared by reacting oligohydridoorganosilazanes of the general formula (R.sup.1 SiHNH).sub.n, in which n is about 3 to about 12, with at least one of the chlorosilanes R.sup.2 SiHCl.sub.2, R.sup.3 SiCl.sub.3, Cl.sub.2 R.sup.4 Si--CH.sub.2 CH.sub.2 --SiR.sup.4 Cl.sub.2 or Cl.sub.3 Si--CH.sub.2 CH.sub.2 --SiR.sup.5 Cl.sub.2 at 30.degree. C. to 300.degree. C., where the radicals independently of one another have the following meanings:R.sup.1 =a C.sub.1 -C.sub.6 alkyl or C.sub.2 -C.sub.6 alkenyl group,R.sup.2 =a C.sub.2 -C.sub.6 alkenyl group if R.sup.2 SiHCl.sub.2 is reacted with the oligosilazanes by itself, orR.sup.2 =a C.sub.1 -C.sub.6 alkyl or C.sub.2 -C.sub.6 alkenyl group if R.sup.2 SiHCl.sub.2 is reacted with the oligosilazanes as a mixture with other chlorosilanes, andR.sup.3, R.sup.4, R.sup.5 =a C.sub.1 -C.sub.6 alkyl or C.sub.C.sub.2 -C.sub.6 alkenyl group,and where R.sup.3 SiCl.sub.3 is used only as a mixture with at least one of the other chlorosilanes (containing R.sup.2, R.sup.4 or R.sup.5).The polymeric hydridochlorosilazanes according to the invention can be converted into polysilazanes by reaction with ammonia, and these in turn can be pyrolyzed to form ceramic materials containing silicon nitride.
摘要:
The invention relates to a process for the production of a ceramic/fiber composite.The process comprises impregnating fibers with a molten polysilazane in a first step, converting the polysilazane in the fibers into the infusible state in a second step and, in a third step, heating the impregnated fibers to 800.degree. to 2000.degree. C. in an atmosphere of nitrogen, noble gas, or ammonia.
摘要:
The invention relates to a novel sinterable ceramic powder, to its preparation, to its processing to form silicon nitride ceramic and to said material itself and its use. The sinterable ceramic powder is prepared by dissolving the polysilazane of formula (I)[CH.sub.3 SiHNH].sub.n [CH.sub.3 SiN].sub.nwhere n is about 10 to 12, in an organic solvent, suspending a pulverulent sinter aid in this solution and then evaporating the solvent and pyrolyzing the residue in an inert gas atmosphere at 500.degree. to 1600.degree. C.The resulting ceramic powder can be used to form a shaped article and then to manufacture silicon nitride ceramic by sintering. It is also possible, however, to form a shaped article from the as yet unpyrolyzed residue obtained after evaporation of the solvent, and then to pyrolyze and sinter said article.The ceramic obtained can be used to manufacture components subject to high mechanical, thermal and corrosive stress.
摘要翻译:本发明涉及一种新型的可烧结陶瓷粉末,用于其制备,以形成氮化硅陶瓷的加工以及所述材料本身及其用途。 可烧结陶瓷粉末是通过在有机溶剂中溶解式(I)[CH3SiHNH] n [CH3SiN] n的聚硅氮烷[N,N-二甲基甲酰胺] n [CH3SiN] n,其中n为约10〜12,将粉状烧结助剂悬浮在该溶液中,然后蒸发溶剂, 在惰性气体气氛中在500〜1600℃下热解残渣。得到的陶瓷粉末可用于形成成形制品,然后通过烧结制造氮化硅陶瓷。 然而,也可以从蒸发溶剂后获得的仍然未裂解的残余物形成成型制品,然后热解并烧结所述制品。 获得的陶瓷可用于制造受到高机械,热和腐蚀应力的部件。
摘要:
The invention relates to a process for the production of ceramic material containing silicon nitride, such as fibers, coatings or moldings. In this process, polymeric hydridochlorosilazanes are rendered infusible at a temperature below their softening point by treatment with gaseous NH.sub.3 and are then pyrolyzed in an atmosphere containing NH.sub.3 at 700.degree. to 1500.degree. C. Fibers, coatings or moldings containing silicon nitride are produced by first producing appropriate structures from a melt of the polymeric hydridochlorosilazane and then rendering them infusible and pyrolyzing them.
摘要:
The invention relates to novel polymeric hydridosilazanes, processes for their preparation and their use for the preparation of ceramic material containing silicon nitride. To prepare the polymeric hydridosilazanes, polymeric hydridochlorosilazanes are reacted with NH.sub.3. To prepare the ceramic material containing silicon nitride, the polymeric hydridosilazanes are then pyrolyzed.
摘要:
The invention relates to novel polymeric hydridochlorosilazanes and a process for their preparation. The compounds according to the invention can be converted into polyhydridosilaznes by reaction with ammonia, and these can in turn be pyrolyzed to ceramic material containing silicon nitride. To prepare the polymeric hydridochlorosilazanes, oligohydridoalkylsilazanes (R.sup.1 SiHNH).sub.n are reacted with a dichlorohydridoalkylsilane R.sup.2 SiHCl.sub.2.
摘要:
The invention relates to novel polymeric hydridosilazanes, processes for their preparation and their use for the preparation of ceramic material containing silicon nitride. To prepare the polymeric hydridosilazanes, polymeric hydridochlorosilazanes are reacted with NH.sub.3. To prepare the ceramic material containing silicon nitride, the polymeric hydridosilazanes are then pyrolyzed.
摘要:
The invention relates to novel polymeric hydridosilazanes, their preparation, their conversion into silicon nitride-containing ceramic material, and this material itself. To prepare the polymeric hydridosilazanes, polymeric hydridothiosilazanes are reacted with NH.sub.3. To prepare the silicon nitride-containing ceramic material, the polymeric hydridosilazanes are then pyrolyzed.
摘要:
Polymeric hydridosilazanes, processes for the preparation thereof, silicon nitride-containing ceramic materials which can be prepared therefrom, and the preparation thereof.The invention relates to novel polymeric hydridosilazanes, their preparation, their conversion into silicon nitride-containing ceramic material, and this material itself. To prepare the polymeric hydridosilazanes, polymeric hydridothiosilazanes are reacted with NH.sub.3. To prepare the silicon nitride-containing ceramic material, the polymeric hydridosilazanes are then pyrolyzed.
摘要:
Compounds of the general formula ##STR1## wherein X and Y are the same or different and denote oxygen or sulfur,R.sub.1 is an ethylenically unsaturated aliphatic radical containing from 2 to 6 carbon atoms, andR.sub.2 is a saturated aliphatic radical containing from 1 to 6 carbon atoms or an aryl radical containing from 6 to 10 carbon atoms,are intermediate products used for the preparation of photocrosslinkable polymers with lateral (thio)phosphinyl(thio)urethane groups or (thio)phosphinyl(thio)urea groups, which polymers are useful in photosensitive mixtures and recording material.