Hybridization effect of functionalized microcrystalline cellulose and liquid acrylonitrile butadiene rubber on epoxy

• Published in: Journal of composite materials Vol. 56; no. 18; pp. 2867 - 2877
• Main Authors: Motta Neves, Roberta, Kerche, Eduardo Fischer, Zattera, Ademir José, Amico, Sandro Campos
• Format: Journal Article
• Language: English
• Published: London, England SAGE Publications 01-08-2022
• Subjects: Epoxy resin; liquid rubber; hybrid composites; cellulose; mechanical properties
• ISSN: 0021-9983; 1530-793X
• DOI: 10.1177/00219983221107096

Toughening epoxy resins by adding different agents has been employed as a way to reduce brittleness in composites. Some hybridization strategies combining liquid rubbers and rigid fillers can be found in the literature, but the pair cellulose-based reinforcement, such as microcrystalline cellulose (MCC), and liquid acrylonitrile butadiene rubber (NBR) is hardly studied. The aim of this work is to investigate the effect of hybridizing MCC and amino-functionalized MCC (MCCSi) with NBR on the thermal, mechanical, and dynamic-mechanical behavior of epoxy. X-ray microtomography showed a good dispersion of MCCSi fillers in epoxy/NBR compared to the non-treated MCC filler. NBR with MCCSi was found to slightly increase the thermal stability of epoxy. The addition of MCC, regardless of the functionalization, decreased tensile strength and elastic modulus, but improved impact strength and toughness properties (KIC). Also, MCCSi composites displayed better dynamic-mechanical behavior, attributed to the enhanced chemical interaction, with a small effect on glass transition temperature.