Poly(butylene succinate)/cellulose composite monofilaments with microelastic response based on interfacial bonding

Biodegradable fibers have been widely developed for advanced textile fields, but their practical applications are limited by large plastic deformation. To solve this problem, we developed a solvent-free melt spinning method to prepare poly(butylene succinate)/microcrystalline cellulose (PBS/MCC) composite monofilaments. The high modulus and rigidity of MCC limit PBS plastic deformation and the in-situ formed hydrogen bonds between MCC and amorphous PBS improved MCC dispersion and led to the formation of rigid MCC physical crosslink points. The composite monofilaments with 10-25 wt% of MCC after multi-stage and high-ratio hot stretching showed a double yielding behavior and microelastic response, indicating the permanent deformation resistance of the composite monofilaments under small deformation. Moreover, the addition of MCC improved the biodegradability of the composite monofilaments after 60 days buried in soil. Therefore, our study provides a design strategy of microelastic composite monofilaments for maintaining dimensional stability during use and accelerating degradation during waste.