The present invention provides a cross linked polyolefin thermoset material, comprising maleic anhydride functionalized reactive polyolefin wax cross linked with a polyamine. The thermoset may be made by a method involving reaction of a maleic anhydride functionalized reactive polyolefin wax with a polyamine. The polyolefin may be polyethylene, polypropylene and their copolymers. The polyamine is a primary or secondary alkyl polyamines, alkyl ether polyamines, aryl polyamines. Polyols may be used instead of polyamines, for example alkyl polyols, alkyl ether polyols or aryl polyols.