A New Self-Healing Degradable Copolymer Based on Polylactide and Poly(p-dioxanone)

Laifa Tong; Mi Zhou; Yulong Chen; Kai Lu; Zhaohua Zhang; Yuesong Mu; Zejian He

doi:10.3390/molecules28104021

A New Self-Healing Degradable Copolymer Based on Polylactide and Poly(p-dioxanone)

Molecules. 2023 May 11;28(10):4021. doi: 10.3390/molecules28104021.

Authors

Laifa Tong¹, Mi Zhou¹, Yulong Chen¹, Kai Lu¹, Zhaohua Zhang¹, Yuesong Mu¹, Zejian He¹

Affiliation

¹ Material Science and Engineering, College of Materials Science and Engineering, Zhejiang University of Technology, Hangzhou 310000, China.

Abstract

In this paper, the copolymerization of poly (p-dioxanone) (PPDO) and polylactide (PLA) was carried out via a Diels-Alder reaction to obtain a new biodegradable copolymer with self-healing abilities. By altering the molecular weights of PPDO and PLA precursors, a series of copolymers (DA2300, DA3200, DA4700 and DA5500) with various chain segment lengths were created. After verifying the structure and molecular weight by 1H NMR, FT-IR and GPC, the crystallization behavior, self-healing properties and degradation properties of the copolymers were evaluated by DSC, POM, XRD, rheological measurements and enzymatic degradation. The results show that copolymerization based on the DA reaction effectively avoids the phase separation of PPDO and PLA. Among the products, DA4700 showed a better crystallization performance than PLA, and the half-crystallization time was 2.8 min. Compared to PPDO, the heat resistance of the DA copolymers was improved and the Tm increased from 93 °C to 103 °C. Significantly, the rheological data also confirmed that the copolymer was self-healing and showed obvious self-repairing properties after simple tempering. In addition, an enzyme degradation experiment showed that the DA copolymer can be degraded by a certain amount, with the degradation rate lying between those of PPDO and PLA.

Keywords: Diels–Alder reaction; crystallization behavior; poly(p-dioxanone); polylactide; self-healing.

Grants and funding

This research was funded by Zhang Dahong’s Zhejiang Province Major Science and Technology Special Major Social Development Project, grant number 2013C03017-5.