Methods of preparing polysilynes

Abstract

The invention involves new syntheses for poly(methyl- and ethyl-silyne). The invention also includes silicon carbide (SiC) ceramics that can be produced from poly(methylsilyne), as well as other ceramics, which can be produced from these precursors by modified processing conditions.

1 . A method of making a poly(methylsilyne), the method comprising: 
 a) contacting a halogenated methylsilane with a metallic reagent to produce a reaction mixture;    b) homogenizing the reaction mixture to produce a homogenized reaction mixture;    c) adding to the homogenized reaction mixture a solvent to aid in completing the reaction;    d) refluxing the homogenized reaction mixture for at least about  6  hours to produce a first refluxed reaction mixture;    e) contacting the first refluxed reaction mixture with an alkylating agent to produce an end-capped reaction mixture;    f) refluxing the end-capped reaction mixture to produce a second refluxed reaction mixture; and    h) quenching the second refluxed reaction mixture with an aqueous solvent that lacks any alcohol to produce non-pyrophoric poly(methylsilyne).    
     
     
         2 . The method of  claim 1 , wherein the aqueous solvent is water.  
     
     
         3 . The method of  claim 1 , wherein the solvent is tetrahydrofuran.  
     
     
         4 . The method of  claim 1 , wherein the halogenated methylsilane is methyltrichlorosilane.  
     
     
         5 . The method of  claim 1 , wherein the metallic reagent is a sodium potassium alloy.  
     
     
         6 . The method of  claim 1 , wherein the alkylating agent is methylithium.  
     
     
         7 . The method of  claim 1 , wherein the halogenated methyl silane is mixed with a non-polar solvent.  
     
     
         8 . The method of  claim 7 , wherein the non-polar solvent is pentane.  
     
     
         9 . The method of  claim 1 , wherein ultrasound is used to perform the homogenization.  
     
     
         10 . A method of making a poly(ethylsilyne), the method comprising: 
 a) contacting a halogenated ethylsilane with a metallic reagent to produce a reaction mixture;    b) homogenizing the reaction mixture to produce a homogenized reaction mixture;    c) slowly adding to the homogenized reaction mixture a solvent, wherein at least 1.0 ml of the solvent is added drop-wise, to aid in completing the reaction;    d) adding to the homogenized reaction mixture an alkylating agent to produce an end-capped reaction mixture; and    e) quenching the end-capped reaction mixture with an aqueous solvent that lacks any alcohol to produce non-pyrophoric poly(ethylsilyne).    
     
     
         11 . The method of  claim 10 , wherein the aqueous solvent is water.  
     
     
         12 . The method of  claim 10 , wherein the solvent is tetrahydrofuran.  
     
     
         13 . The method of  claim 1 , wherein the halogenated ethylsilane is ethyltrichlorosilane.  
     
     
         14 . The method of  claim 1 , wherein the metallic reagent is a sodium potassium alloy.  
     
     
         15 . The method of  claim 1 , wherein the alkylating agent is methylithium.  
     
     
         16 . The method of  claim 1 , wherein the halogenated ethylsilane is mixed with a non-polar solvent.  
     
     
         17 . The method of  claim 16 , wherein the non-polar solvent is pentane.  
     
     
         18 . The method of  claim 1 , wherein ultrasound is used to perform the homogenization.  
     
     
         19 . The method of  claim 10 , further comprising refluxing the homogenized reaction mixture.  
     
     
         20 . The method of  claim 10 , further comprising refluxing the end-capped reaction mixture.  
     
     
         21 - 33 . (canceled)