Hemp fiber reinforced dual dynamic network vitrimer biocomposites with direct incorporation of amino silane

Journal Article · Sat Dec 16 00:00:00 UTC 2023 · Chemical Engineering Journal

DOI: https://doi.org/10.1016/j.cej.2023.148091 · OSTI ID:2475414

Fei, Mingen ^[1]; Liu, Wangcheng ^[1]; Shao, Lin ^[1]; Cao, Yiding ^[1]; Bliss, Brian J. ^[1]; Zhao, Baoming  ^[1]; Zhang, Jinwen  ^[1]

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1. Washington State University, Pullman, WA (United States)

Natural fiber composites are inexpensive and renewable alternatives to traditional fiber reinforced polymers (FRPs). However, existing natural fiber composites primarily rely on petrochemical based thermosetting matrices, which are difficult to recycle due to their stable crosslinked network structures. To address this challenge, it is desirable to develop natural fiber composites with inherently recyclable biobased matrices. In this study, we developed a dual dynamic network vitrimer matrix from hempseed oil and limonene derivatives and demonstrated its application in hemp fiber reinforced composites. To improve the weak interface between hemp fiber and the polymer matrix, a common challenge in the realm of natural fiber composites, we directly incorporated amino silane into the vitrimer matrix. The amino silane participated in the polymer network, increasing the crosslink density and toughening the matrix, as evidenced by a significantly improved impact strength from 3.5 kJ/m² to 10.3 kJ/m². Moreover, the incorporation of amino silane resulted in a lower water absorption by 11% in 7-day soaking for the composites, demonstrating improved fiber/matrix interfacial interaction. Furthermore, our biobased vitrimer matrix exhibits both imine and hydroxy-ester dynamic bonds, which enable the recycling of the biocomposite through a mild and cost-effective aminolysis process (100°C, 3h, ambient pressure). The decomposed polymer matrix was successfully reused as a polyol for polyurethane adhesives, and the surface morphology of recovered hemp fibers was analyzed and compared with that of the original fibers. Furthermore, these findings will help broaden the use of vitrimers for practical natural fiber composite applications, raise awareness of the problem of recycling natural fiber composite waste, and shed light on the interfacial challenge of natural fiber reinforced vitrimer composites.

• Research Organization: Washington State University, Pullman, WA (United States)
• Sponsoring Organization: USDOE Office of Energy Efficiency and Renewable Energy (EERE), Office of Sustainable Transportation. Bioenergy Technologies Office (BETO)
• Grant/Contract Number: EE0008931
• OSTI ID: 2475414
• Journal Information: Chemical Engineering Journal, Journal Name: Chemical Engineering Journal Vol. 480; ISSN 1385-8947
• Publisher: ElsevierCopyright Statement
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
42 ENGINEERING
Aminolysis
Hemp fiber
Natural fiber composites
Silane incorporation
Vitrimer