Polycarbosilane, method for producing same, silica composition for coating application, and silica film
A polycarbosilane has a main chain in which silicon atoms and carbon atoms are alternately repeated, and includes a structural unit shown by the following general formula (1), a structural unit shown by the following general formula (2), a structural unit shown by the following general formula (3), and a structural unit shown by the following general formula (4).
1. A polycarbosilane having a main chain in which silicon atoms and carbon atoms are alternately repeated, and comprising a structural unit shown by the following general formula (1), a structural unit shown by the following general formula (2), a structural unit shown by the following general formula (3), and a structural unit shown by the following general formula (4),
wherein R represents a monovalent hydrocarbon group.
2. The polycarbosilane according to claim 1 , the polycarbosilane further comprising at least one structural unit shown by the following formulas (5) to (9),
3. The polycarbosilane according to claim 1 , the polycarbosilane having a weight average molecular weight of 300 to 1,000,000 and being soluble in an organic solvent.
4. A silica coating composition comprising the polycarbonate according to claim 1 and an organic solvent.
5. A silica film produced by curing a coating formed using the silica coating composition according to claim 4 .
6. A method for producing a polycarbosilane comprising reacting a raw material polymer having a main chain in which silicon atoms and carbon atoms are alternately repeated and containing a structural unit shown by the following general formula (1) and a structural unit shown by the following general formula (2) with an alcohol in an organic solvent in the presence of a basic catalyst, and reacting the resulting product with water,
7. The method for producing a polycarbosilane according to claim 6 , wherein the raw material polymer further contains at least one of a structural unit shown by the following formula (5), a structural unit shown by the following formula (8), and a structural unit shown by the following formula (9),
8. The method for producing a polycarbosilane according to claim 6 , wherein the reaction with water is carried out by adding an acidic aqueous solution to the reaction system.
9. A polycarbosilane produced by the method for producing a polycarbosilane according to claim 6 .
10. The polycarbosilane according to claim 9 , the polycarbosilane comprising a structural unit shown by the following general formula (1), a structural unit shown by the following general formula (2), a structural unit shown by the following general formula (3), and a structural unit shown by the following general formula (4):
wherein R represents a monovalent hydrocarbon group.
11. The polycarbosilane according to claim 10 , the polycarbosilane further comprising at least one of structural units shown by the following formulas (5) to (9),
wherein R represents a monovalent hydrocarbon group,
12. The polycarbonate according to claim 9 , the polycarbonate having a weight average molecular weight of 300 to 1,000,000 and being soluble in an organic solvent.
13. A silica coating composition comprising the polycarbosilane according to claim 9 , and an organic solvent.
14. A silica film produced by curing a coating formed using the silica coating composition according to claim 13 .