Over the past few decades, much effort has been devoted to the generation of polyolefin nanocomposites, which offers substantial improvements to polyolefin properties with minimal nanofiller mass (0.1 wt%~5 wt%). Nanomaterials covalently grafted with polyolefin show great potential in developing high performance polyolefin nanocomposites. Grafted polyolefin chains generally provide high compatibility and good interfacial interactions between nanomaterials and polyolefin matrix, and thus promote homogeneous dispersion of nanomaterials into polyolefin matrix and enhance mechanical, thermal (and other) properties of polyolefin nanocomposites. Three strategies employed to covalently graft polyolefin to nanomaterials include: graft-onto, graft-from and graft-through. The high availability and reactivity of functionalized polyolefin, together with the difficulties encountered in the latter two approaches, renders “grafting-onto” approach as the mainstream of surface grafting polyolefin to nanomaterials. Both chain end functionalized polyolefin and side group functionalized polyolefin (mainly maleic-anhydride-grafted polyolefin and its derivatives) have been extensively applied in surface grafting polyolefin to nanomaterials via “grafting-onto” approach while reports on “graft-from” and “graft-through” approaches are limited. Here we review recent progress on polyolefin covalently grafted nanomaterials (silica, zero dimensional; carbon nanotube, one dimensional; graphene (oxide), two dimensional) with a focus on the properties of polyolefin nanocomposites derived thereof.

Contents
1 Introduction
2 Graft-onto approach
2.1 Chain end functionalized polyolefin
2.2 Side group functionalized polyolefin
3 Graft-from approach
4 Graft-through approach
5 Conclusion and outlook