Polypropylene having high maleic anhydride content, between about 5 and
about 45 wt %, may be prepared by first reacting a metallocene-prepared
polypropylene having terminal unsaturation with one mole equivalent of
maleic anhydride to give polypropylene having a single unsaturation and a
terminal succinic anhydride moiety. This product is then reacted with
additional maleic anhydride in the presence of a free radical initiator
(such as a peroxide or UV radiation) to give a polypropylene with maleic
anhydride moieties along the backbone. The polypropylene product does not
suffer scission or crosslinking with subsequently undesirable increases
in molecular weight or viscosity. The maleic anhydride moieties provide
reactivity to the polypropylene and thus expand its uses and
applications.