Acetylene-terminated phenylquinoxaline oligomers

The initial synthesis of acetylenic terminated phenylquinoxaline oligomers was reported in 1975. An alternate synthesis reported in 1976 involved endcapping o-diamino-termi-nated phenylquinoxaline oligomers with 4-(4-ethynylphenoxy)benzil to yield acetylene-terminated phenylquinoxaline oligomers (ATPQs) as shown in the representative scheme in Eq. (4) ... 

A substantial effort in this laboratory has been directed toward the synthesis and characterization of acetylene terminated oligomers for use as addition-curable, moisture-resistant, thermoset systems. Early work on the acetylene-terminated phenylquinoxalines demonstrated the moisture insensitivity of the product generated from the thermal cure. Studies of various difunctional acetylene-terminated monomers has demonstrated that the polymerization is a free radical propogation of the acetylene moiety to a linear conjugated polyene. 

The acetylene terminated quinoxaline oligomers, referred to as ATQ s, are prepared j5 from the reaction of benzil end-capped phenylquinoxaline oligomers and 3(3,4-diaminophenoxy)-phenylacetylene. The benzil end-capped oligomers are pre-... 

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