Development of Noncovalently Bonded Thermoplastic Elastomers and Their Application to Structural Adhesives

Thermoplastic elastomers (TPEs) are polymeric materials that combine excellent processability with rubber elasticity. In recent years, the development of TPEs incorporating dynamic and reversible noncovalent interactions within elastomers, such as hydrogen bonding and ionic interactions, has attracted considerable attention as a promising strategy for achieving higher strength and toughness. This article reviews styrenic TPEs containing noncovalent functional groups, with particular emphasis on their molecular design, rheological behavior, mechanical properties, chemical modification of commercially available styrenic TPEs, and applications as additives for structural adhesives. These noncovalently bonded TPEs are promising not only as high-performance elastomers but also for improving the performance of structural adhesives and other advanced materials. Their practical applications are expected to contribute to the lightweighting and electrification of mobility, thereby supporting carbon neutrality.