摘要 |
A halogenated aryl ether oligomer is formed by halogenation of an aryl ether oligomer and is useful as a flame retardant for flammable macromolecular materials. Typically, the halogenated aryl ether oligomer comprises the following repeating monomeric units: wherein R is hydrogen or alkyl, especially C1 to C4 alkyl, Hal is halogen, m is at least 1, n is 0 to 3 and x is at least 2. |