| 摘要 |
METHYLPOLYSILANES HAVING CONTROLLABLE RHEOLOGY AND METHOD FOR THEIR PREPARATION A process for the preparation of a methylpolysilane having a controllable rheology, including a controllable glass transition temperature is provided which includes the steps of heating together at least one alkoxy-functional disilane selected from the group consisting of disilane having three and four alkoxy groups bonded to the silicon atoms and mixtures thereof, with an amount of a dialkoxydisilane effective to control the glass transition temperature of the resulting polymer within the range of from about 0 to about 200.degree.C. The reaction is carried out in the presence of a catalyst which is a source of alkoxide ions to catalyze the redistribution reaction. The redistribution reaction produces oligomer and longer chain polymeric silanes having greater than seven silicon atoms in the polymer chain. Methylpolysilanes formed in accordance with the practice of the present invention may then be readily formed into fibers by a conventional spinning process. Alternatively, the methylpolysilanes of the present invention may also find use as binders, coatings and films for ceramic compositions. The methylpolysilanes may be pyrolyzed to form ceramic compositions. |
