polymeric hydrocarbons having reactive borane groups at chain ends or in the polymer chain are described . these types of polymers can be used as intermediate materials for preparing a broad range of polymers which have functional groups located at both ends of the polymer chain . the process of preparing the borane - containing polymers involves metathesis degradation of the polymer at the double bond locations in the backbone and simultaneous functionalization of the broken chain ends by borane monomers . depending on the nature of the borane monomer , the location of boron atoms can be controlled to be at either the chain ends or in the polymer backbone . the concentration of boron in the resulting polymer is related to the reaction time and the mole ratio between borane monomer and the double bonds in the starting hydrocarbon polymer . in turn , the borane groups are interconvertible to various functional groups , such as oh , nh 2 , and halides , under mild reaction conditions . overall , the chemistry is very general and is applicable to most hydrocarbon polymers . a wide variety of telechelic polymers are obtained .