Terpolymerization of Ethylene and Two Different Methoxyaryl‐Substituted Propylenes by Scandium Catalyst Makes Tough and Fast Self‐Healing Elastomers

The terpolymerization of a non‐polar olefin (such as ethylene) and two different polar functional olefins in a controlled fashion is of great interest and importance but has hardly been explored to date. We report for the first time the terpolymerization of ethylene (E) and two different methoxyaryl‐substituted propylenes (A^R1P=hexylanisyl propylene; A^R2P=methoxynaphthyl propylene or methoxypyrenyl propylene) by a half‐sandwich scandium catalyst. The terpolymerization took place in a sequence‐controlled fashion, affording unique multi‐block copolymers composed of two different ethylene‐alt‐methoxyarylpropylene sequences E‐alt‐A^R1P (soft segments) and E‐alt‐A^R2P (hard segments) and relatively short ethylene–ethylene (EE) blocks (crystalline segments). The terpolymers exhibited excellent elasticity and unprecedented self‐healing as a result of microphase separation of nanodomains of the crystalline EE segments and the hard amorphous E‐alt‐A^R2P segments from a very flexible E‐alt‐A^R1P matrix, demonstrating unique synergy of the three different components.