Development of Toughening Technology for Styrenic Thermoplastic Elastomers by Incorporating Non-Covalent Interactions

We have developed schemes for synthesizing polystyrene-b-polyisoprene-b-polystyrene (SIS) with non-covalent bonding groups via the post-polymerization chemical modification that is an industrially-friendly scheme. SIS was first reacted with maleic anhydride in a diluent, followed by reacting with alkylamine. By neutralizing the carboxy group with a metal alkoxide, ionically-modified SIS (i-SIS) was also prepared. i-SIS with a sodium cation (i-SIS(Na)) or a barium cation (i-SIS(Ba)) exhibited excellent tensile toughness of 480 and 230 MJ m–3 , respectively. Drop weight impact tests also revealed that i-SIS(Ba) exhibited higher impact resistance than that of typical high-strength glass fiber-reinforced plastic. In the future, by achieving optimization of production of i-SIS in an industrial scale, i-SIS can be used for production of lightweight automobiles, resulting in contribution to achieving net-zero carbon and sustainable society.