Polysilane preceramic polymers

Claim 1

A polysilane, which is solid at 25° C. having the average unit formula (R 2 Si)(RSi)(R'Si) wherein each R is independently selected from alkyl radicals containing 1 to 4 carbon atoms, wherein each R' is independently selected from the group consisting of alkyl radicals of at least six carbon atoms, phenyl radicals, and radicals of the formula A y X.sub.(3-y) Si(CH 2 ) z --where A is a hydrogen atom or an alkyl radical containing 1 to 4 carbon atoms, y is an integer equal to 0 to 3, X is chlorine or bromine, and z is an integer greater than or equal to 1, and where there are from 0 to 40 mole percent (R 2 Si) units, 1 to 99 mole percent (RSi). and 1 to 99 mole percent (R'Si) units and wherein the remaining bonds on silicon are attached to either other silicon atoms, chlorine atoms, or bromine atoms.

Claim 15

A method of preparing a polysilane having average unit formula (R 2 Si)(RSi)(R'Si) wherein each R is independently selected from alkyl radicals containing 1 to 4 carbon atoms, wherein each R' is independently selected from the group consisting of alkyl radicals of at least six carbon atoms, phenyl radicals, and radicals of the formula A y X.sub.(3-y) Si(CH 2 ) z -- wherein each A independently selected from is a hydrogen atom or alkyl radicals containing 1 to 4 carbon atoms, y is an integer equal to 0 to 3, X is chlorine or bromine, and z is an integer greater than or equal to 1, l wherein there are from 0 to 40 mole percent (R 2 Si) units, 1 to 99 mole percent (RSi) units, and 1 to 99 mole percent (R'Si) units, and where the remaining bonds on silicon are attached to either other silicon atoms, chlorine atoms, or bromine atoms, wherein such method comprises treating a mixture containing a chlorine-containing or bromine-containing disilane and 1 to 60 weight percent of a monoorganosilane of formula R'SiX 3 , where R' is selected from the group consisting of alkyl radicals of at least six carbon atoms, phenyl radicals and radicals of the formula A y X.sub.(3-y) Si(CH 2 ) z -- wherein each A is independently selected from a hydrogen atom or alkyl radicals containing 1 to 4 carbon atoms, y is an integer equal to 0 to 3, X is chlorine or bromine, and z is an integer greater than or equal to 1, with 0.001 to 10 weight percent of a rearrangement catalyst at a temperature of 100° C. to 340° C. while distilling by-produced volatile materials until there is produced a polysilane, which is a solid at 25° C. having the average formula (R 2 Si)(RSi)(R'Si) wherein each R is independently selected from alkyl radicals containing 1 to 4 carbon atoms, where R' is selected from the group consisting of alkyl radicals of at least six carbon atoms, phenyl radicals,and radicals of the formula A y X.sub.(3-y) Si(CH 2 ) z -- wherein each A is independently selected from a hydrogen atom or alkyl radicals containing 1 to 4 carbon atoms, y is an integer equal to 0 to 3, X is chlorine or bromine, and z is an integer greater than or equal to 1. and where there are from 0 to 40 mole percent (R 2 Si) units, 1 to 99 mole percent (RSi) units, and 1 to 99 mole percent (R'Si) units and wherein the remaining bonds on silicon are attached to either other silicon atoms, chlorine atoms, or bromine atoms.

Claim 16

A method of preparing a polysilane having average unit formula (R 2 Si)(RSi)(R'Si) wherein each R is independently selected from alkyl radicals containing 1 to 4 carbon atoms, wherein each R' is independently selected from the group consisting of alkyl radicals of at least six carbon atoms, phenyl radicals, and radicals of the formula A y X.sub.(3-y) Si(CH 2 ) z -- wherein each A independently selected from is a hydrogen atom or alkyl radicals containing 1 to 4 carbon atoms, y is an integer equal to 0 to 3, X is chlorine or bromine, and z is an integer greater than or equal to 1, l wherein there are from 0 to 40 mole percent (R 2 Si) units, 1 to 99 mole percent (RSi) units, and 1 to 99 mole percent (R'Si) units, and where the remaining bonds on silicon are attached to either other silicon atoms, chlorine atoms, or bromine atoms, wherein such method comprises treating a mixture containing a chlorine-containing or bromine-containing disilane and 1 to 60 weight percent of a monoorganosilane of formula R'SiX 3 , where R' is selected from the group consisting of alkyl radicals of at least six carbon atoms, phenyl radicals and radicals of the formula A y X.sub.(3-y) Si(CH 2 ) z -- wherein each A is independently selected from a hydrogen atom or alkyl radicals containing 1 to 4 carbon atoms, y is an integer equal to 0 to 3, X is chlorine or bromine, and z is an integer greater than or equal to 1, with 0.001 to 10 weight percent of a rearrangement catalyst at a temperature of 100° C. to 340° C. while distilling by-produced volatile materials until there is produced a polysilane, which is a solid at 25° C. having the average formula (R 2 Si)(RSi)(R'Si) wherein each R is independently selected from alkyl radicals containing 1 to 4 carbon atoms, where R' is selected from the group consisting of alkyl radicals of at least six carbon atoms, phenyl radicals,and radicals of the formula A y X.sub.(3-y) Si(CH 2 ) z -- wherein each A is independently selected from a hydrogen atom or alkyl radicals containing 1 to 4 carbon atoms, y is an integer equal to 0 to 3, X is chlorine or bromine, and z is an integer greater than or equal to 1. and where there are from 0 to 40 mole percent (R 2 Si) units, 1 to 99 mole percent (RSi) units, and 1 to 99 mole percent (R'Si) units and wherein the remaining bonds on silicon are attached to either other silicon atoms, chlorine atoms, or bromine atoms.