Polyhydridosilanes and their conversion to pyropolymers
AssigneeMinnesota Mining and Manufacturing Company
InventorsKatherine A. Brown-Wensley, Robert A. Sinclair
Life of this patent
Estimating the term…
Abstract
A polyhydridosilane has a catenated silicon backbone of 9 to 4000 silicon atoms with an average number of hydrogen atoms per silicon atoms in the range of 0.3 to 2.2, at least 0.1 gram of the polyhydridosilane being soluble at 20.degree. C. in 100 grams of tetrahydrofuran, toluene, or methylene chloride. The polyhydridosilane can be derivatized or it can be converted to a pyropolymer or a nitrogen-containing pyropolymer which is useful as an abrasive, ceramic, electrical, or electro-optical material.
Claims19
A polyhydridosilane having a catenated silicon backbone having an average of 20 to 4000 silicon atoms with a number of hydride atoms per silicon atom in the range of 0.3 to 2.2, at least 0.1 gram of said polyhydridosilane being soluble at 20.degree. C. in 100 grams of at least one of the organic solvents selected from the group consisting of tetrahydrofuran, toluene, and methylene chloride, said polyhydridosilane being tractable and moisture-sensitive.
An organic solvent-soluble polymer having a backbone consisting essentially of repeating monomeric units having the formula ##STR8## where R is the same or different and is independently selected from the group consisting of (1) hydrogen, (2) a linear, branched, or cyclic aliphatic group having 1 to 10 carbon atoms and optionally containing at least one Periodic Group VA or VIA atom, (3) an aromatic group which is unsubstituted or substituted by up to three C.sub.1 to C.sub.10 linear, branched, or cyclic aliphatic groups, said aromatic or aliphatic groups optionally containing at least one Periodic Group VA or VIA atom, the total number of carbon atoms being up to 25, (4) a single bond connecting two silicon atoms, (5) a metal atom selected from the group consisting of Periodic Groups IA and IIA, and (6) an inorgano- and organometallic group comprising at least one Periodic Group IB to VIIB, VIII, Lanthanide or Actinide element,
- with the proviso that
- the ratio of hydride to silicon is in the range of 0.3 to 2.2;
- the average number of monomeric units of said formula in the polymer is in the range of 20 to 4,000, and
- said polymer being tractable and moisture-sensitive.
An organic solvent-soluble polymer having a backbone consisting essentially of repeating monomeric units having the formula ##STR9## where R is the same or different and is independently selected from the group consisting of (1) hydrogen, (2) a linear, branched, or cyclic aliphatic group having 1 to 10 carbon atoms and optinally containing at least one Periodic Group VA or VIA atom, (3) an aromatic group which is unsubstituted or substituted by up to three C.sub.1 to C.sub.10 linear, branched, or cyclic aliphatic groups, said aromatic or aliphatic groups optionally containing at least one Periodic Group VA or VIA atom, the total number of carbon atoms being up to 25, (4) a single bond connecting two silicon atoms, (5) a metal atom selected from the group consisting of Periodic Groups IA and IIA, and (6) an inorgano- or organometallic group comprising at least one Periodic Group IB to VIIB, VIII, Lanthanide or Actinide element,
- with the proviso that
- the ratio of hydride to silicon is in the range of 0.3 to 2.2;
- the average number of monomeric units of said formula in the polymer is in the range of 9 to 4,000, and
- said polymer being tractable and
- moisture-sensitive,
- said polymer further comprising at least one group selected from ##STR10## wherein R.sup.1 is selected from the group consisting of (1) hydrogen, (2) a linear, branched or cyclic aliphatic group having 1 to 10 carbon atoms and optionally containing at least one catenary oxygen atom, (3) an aromatic group optionally substituted by up to three C.sub.1 to C.sub.10 linear, branched, or cyclic aliphatic groups, said aliphatic and aromatic groups optionally containing at least one catenary oxygen atom, the total number of carbon atoms being up to 25, and (4) a single bond connecting two silicon atoms;
- and
- M is a Periodic Group IA or IIA metal.
A method of preparing a polyhydridosilane having an average of 9 to 4000 silicon atoms and having a hydride to silicon ratio in the range of 0.3 to 2.2 comprising the steps of:
- a. providing at least one hydridosilane having the formula (R.sup.1).sub.2 SiX.sub.2,
- wherein
- R.sup.1 is selected from the group consisting of (1) hydrogen, (2) a linear, branched, or cyclic aliphatic group having 1 to 10 carbon atoms and optionally containing at least one catenary oxygen atom, (3) an aromatic group optionally substituted by up to three C.sub.1 to C.sub.10 linear, branched, or cyclic aliphatic groups, said aliphatic and aromatic groups optionally containing at least one catenary oxygen atom, the total number of carbon atoms being up to 25, and (4) a single bond connecting two silicon atoms;
- X is a halogen atom, and
- b. reacting said at least one hydridosilane in the presence of a catalytically effective amount of naphthalene or other polynuclear aromatic compound with a Periodic Group IA or Group IIA metal or alloy in an amount of at least 1 equivalent of metal per equivalent of halogen in an inert atmosphere and in an inert diluent for a time sufficient to provide a polyhydridosilane,
- at least 0.1 gram of said polyhydridosilane being soluble in 100 grams of organic solvent at 20.degree. C.
A polyhydridosilane having a catenated silicon backbone having an average of 20 to 4000 silicon atoms with a number of hydride per silicon atom in the range of 0.3 to 2.2, at least 0.1 gram of said polyhydridosilane being soluble at 20.degree. C. in 100 grams of at least one of the organic solvents selected from the group consisting of tetrahydrofuran, toluene, and methylene chloride, said polyhydridosilane being tractable and moisture-sensitive.
Dependencies are inferred from the claim text.