Modified preceramic polymers, method of making and ceramic matrix composite formed therefrom
Disclosed is a modified preceramic polymer having a polymer backbone consisting of silicon or a combination of silicon and carbon; and a pendant modifier bonded to the backbone wherein the modifier includes silicon, boron, aluminum, a transition metal, a refractory metal, or a combination thereof. The modified preceramic polymer can be used to form a ceramic matrix composite.
1. A modified preceramic polymer comprising:
a polymer backbone; and
a pendant modifier bonded to the backbone;
wherein the pendant modifier includes silicon, boron, niobium, tantalum, molybdenum, tungsten, rhenium, or a combination thereof; and
the modified preceramic polymer is a reaction product of a preceramic polymer with a modifier source having a reactive group, the reactive group reacted to form the modified preceramic polymer,
the reactive group is an amine, a tri-functional silane, an amide, a hydroxide, a silyl group, a vinyl group, an allyl group, an alkoxide, an alcohol, a substituted ether, or a combination thereof;
wherein the preceramic polymer is a mixture of polysilane and polycarbosilane.
2. The modified preceramic polymer of claim 1 , wherein the pendant modifier includes silicon, boron, or a combination thereof.
3. The modified preceramic polymer of claim 1 , wherein the pendant modifier to backbone silicon atom ratio is 4:1 to 0.05:1.
4. The modified preceramic polymer of claim 1 , wherein the pendant modifier to backbone carbon atom ratio is 4:1 to 0.05:1.
5. The modified preceramic polymer of claim 1 , wherein the polymer backbone consists of silicon and carbon.
6. A method of making a modified preceramic polymer comprising:
reacting a preceramic polymer with a modifier source having a reactive group, the reactive group reacted to form the modified preceramic polymer;
wherein the preceramic polymer comprises (i) a polymer backbone, and (ii) a pendant modifier bonded to the backbone; and
the reactive group is an amine, a tri-functional silane, an amide, a hydroxide, a silyl group, a vinyl group, an allyl group, an alkoxide, an alcohol, a substituted ether, or a combination thereof;
wherein the pendant modifier includes silicon, boron, niobium, tantalum, molybdenum, tungsten, rhenium, or a combination thereof;
wherein the preceramic polymer is a mixture of polysilane and polycarbosilane.
7. The method of claim 6 , wherein the preceramic polymer comprises a vinyl group.