Graftingthrough

Grafting-through is a method in polymer chemistry for synthesizing graft copolymers by incorporating macromonomers—pre-formed polymers that carry a polymerizable end group—into the polymerization mixture together with conventional monomers. In this approach, the macromonomers become part of the growing polymer backbone during copolymerization, while their polymer chains act as the grafted side chains attached to the main chain. The resulting architecture is a graft copolymer in which the grafted chains originate from the macromonomers used in the polymerization.

Compared with grafting-from and grafting-to strategies, grafting-through relies on macromonomers that participate in the polymerization process, allowing side chains to be integrated in a single step. The method can provide relatively high grafting density and predictable graft lengths, but can also encounter challenges from steric hindrance and slower polymerization rates when bulky macromonomers are used. Control over molecular weight, composition, and architecture is often pursued with living or controlled polymerization techniques.

Common macromonomers include polymers functionalized at one end with a polymerizable group such as acrylate, methacrylate, or norbornene moieties. Grafting-through is widely applied in creating graft copolymers for advanced materials, hydrogels, biocompatible networks, and responsive polymers, where precise control of graft density and chain length can tailor mechanical, thermal, and physical properties.

See also: grafting-from, grafting-to, macromonomer, graft copolymer.