Ultra-strong, ultra-tough, and transparent polymer composite with excellent dynamic and biodegradable properties enabled by bicontinuous structure

Developing plastics that can integrate mechanical (strength and toughness) and dynamic properties (recyclability, repairability, and biodegradability) is commonly challenging. In this work, inspired by the reinforced concrete structure, an ultra-strong and ultra-tough sustainable polymer composite was constructed through uniformly dispersing cellulose nanofiber in a poly(vinyl alcohol) matrix to form a bicontinuous interwoven network structure based on strong yet dynamic hydrogen bonding crosslink sites. The obtained composite showed an ultra-high toughness, a high tensile fracture strength, good Young's modulus and transparency, as well as excellent dynamic properties including good healing ability, recyclability, and biodegradability. Besides, with excellent gas barrier ability and good water vapor permeability, the composite showed great promise to replace traditional polymers for food packaging and preservation. At last, the mechanism behind the good performances is expected to inspire the design of other healable and green polymers in the future.

Automated summary

In this study, an ultra-strong and ultra-tough sustainable polymer composite was developed by dispersing cellulose nanofiber in a poly(vinyl alcohol) matrix. The composite exhibited excellent mechanical properties and dynamic properties, such as high toughness, good healing ability, recyclability, and biodegradability. It also showed great potential for food packaging and preservation due to its gas barrier ability and water vapor permeability. The mechanism behind the impressive performances is expected to inspire the design of other healable and green polymers in the future.