Wood Cellulose Nanofibers Grafted with Poly(ε-caprolactone) Catalyzed by ZnEu-MOF for Functionalization and Surface Modification of PCL Films

Jinying Pang; Tanlin Jiang; Zhilin Ke; Yu Xiao; Weizhou Li; Shuhua Zhang; Penghu Guo

doi:10.3390/nano13131904

Wood Cellulose Nanofibers Grafted with Poly(ε-caprolactone) Catalyzed by ZnEu-MOF for Functionalization and Surface Modification of PCL Films

Nanomaterials (Basel). 2023 Jun 21;13(13):1904. doi: 10.3390/nano13131904.

Authors

Jinying Pang^{1

2}, Tanlin Jiang^{2

3}, Zhilin Ke^{1

4}, Yu Xiao⁴, Weizhou Li^{3

5}, Shuhua Zhang^{1

4}, Penghu Guo⁴

Affiliations

¹ Guangxi Key Laboratory of Electrochemical and Magnetochemical Functional Materials, College of Materials Science and Engineering, Guilin University of Technology, Guilin 541004, China.
² Guangxi Key Laboratory of Natural Polymer Chemistry and Physics, College of Chemistry and Materials, Nanning Normal University, Nanning 530001, China.
³ College of Resources, Environment and Materials, Guangxi University, Nanning 530004, China.
⁴ Key Laboratory of Petrochemical Pollution Control of Guangdong Higher Education Institutes, Guangdong Provincial Key Laboratory of Petrochemical Pollution Process and Control (College of Chemistry), Guangdong University of Petrochemical Technology, Maoming 525000, China.
⁵ School of Materials Science and Engineering, Xiamen University of Technology, Xiamen 361024, China.

Abstract

Renewable cellulose nanofiber (CNF)-reinforced biodegradable polymers (such as polycaprolactone (PCL)) are used in agriculture, food packaging, and sustained drug release. However, the interfacial incompatibility between hydrophilic CNFs and hydrophobic PCL has limited further application as high-performance biomaterials. In this work, using a novel ZnEu-MOF as the catalyst, graft copolymers (GCL) with CNFs were grafted with poly(ε-caprolactone) (ε-CL) via homogeneous ring-opening polymerization (ROP), and used as strengthening/toughening nanofillers for PCL to fabricate light composite films (LCFs). The results showed that the ZnEu-MOF ([ZnEu(L)₂(HL)(H₂O)_0.39(CH₃OH)_0.61]·H₂O, H₂L is 5-(1H-imidazol-1-yl)-1,3-benzenedicarboxylic acids) was an efficient catalyst, with low toxicity, good stability, and fluorescence emissions, and the GCL could efficiently promote the dispersion of CNFs and improve the compatibility of the CNFs and PCL. Due to the synergistic effect of the ZnEu-MOF and CNFs, considerable improvements in the mechanical properties and high-intensity fluorescence were obtained in the LCFs. The 4 wt% GCL provided the LCF with the highest strength and elastic modulus, which increased by 247.75% and 109.94% compared to CNF/PCL, respectively, showing the best elongation at break of 917%, which was 33-fold higher than CNF/PCL. Therefore, the ZnEu-MOF represented a novel bifunctional material for ROP reactions and offered a promising modification strategy for preparing high-performance polymer composites for agriculture and biomedical applications.

Keywords: GCL; ZnEu-MOF; catalyst; fluorescence; light composite films; mechanical properties.

Grants and funding

This work was supported by the Nature Science Foundation of China (No. 21861014), the Guangdong Basic and Applied Basic Research Foundation (No. 2019A1515110346), the Talent recruitment of Guangdong University of Petrochemical Technology (No. 2020rc033, 2019rc053), the Industry-University Collaborative Research Project (No. 2019C002005), and the Guangxi Natural Science Foundation Project of China (contract No. 2020GXNSFBA159038).