High Performance Biobased Epoxy Nanocomposite Reinforced with a Bacterial Cellulose Nanofiber Network

Abstract

This work describes the preparation and characterization of biobased fiber reinforced resins using bacterial cellulose (BC) as the matrix reinforcing phase and diglycidyl ether diphenolate ethyl ester (DGEDP-ethyl) as the biobased epoxy resin. BC mats were prepared by static cultivation of strain Gluconacetobacter xylinus ATCC 700178 in Hestrin−Schramm medium augmented with mannitol in sterile containers. After freeze-drying, the surface of the BC matrix fibers was modified to introduce trimethylsilyl moieties (BC TMS ). Reinforced by BC TMS nanofiber networks were fabricated by impregnation of BC TMS matrixes with the resin mixture followed by hot-pressing and curing. Resulting DGEDP-ethyl/BC TMS composites with 5, 10, 20, and 30%-by-vol BC TMS network loading were formed. The BC network proved effective in reinforcing the epoxy resin matrix. The composite Young's modulus (E T ) increased from 1.22 ± 0.41 GPA for the neat DGEDP-ethyl thermoset to 8.8 ± 0.98 for the composite with 30%by-vol BC TMS . Furthermore, the storage modulus (E′) increased for DGEDP-ethyl/30%BC TMS relative to the neat DGEDPethyl resin below T g (30 °C) by 3-fold (2.27 to 7.7 GPA) and above T g (180 °C) by 100-fold. This work highlights the potential to use prefabricated BC matrixes produced by microbial fermentation along with a biobased epoxy resin to provide highperformance biobased composites.

Nanocellulose: From Fundamentals to Advanced Applications

“…Nanocellulose exhibits some exclusive features such as exceptional mechanical properties (i.e., low density, high flexibility, and strength while being chemically inert) (Lavoine and Bergström, 2017) and thermal properties (Gan et al, 2020). Over the past few decades, many research studies have been conducted on the reinforcement of polymer matrix nanocomposites, for instance, natural rubber nanocomposites (Neto et al, 2016;Cao et al, 2018;Dominic et al, 2020), polylactic acid nanocomposites (Gitari et al, 2019;Rigotti et al, 2019), epoxy nanocomposites (Ayrilmis et al, 2019;Yan et al, 2019;Yue et al, 2019), and polystyrene nanocomposites (Clarke et al, 2019;Neves et al, 2019), where nanocellulose has been introduced as a reinforcing agent.…”

Waste brewed tea leaf derived cellulose nanofiber reinforced fully bio-based waterborne polyester nanocomposite as an environmentally benign material

“…19 A viable route for the fabrication of epoxy resin and nanocellulose based nanocomposite was demonstrated by Yue et al in which they impregnated a pre-percolated bacterial cellulose network with the bio-based epoxy resin followed by hot-pressing and curing, which further avoids ber agglomeration and high viscosities. 20 However, the reported cellulose polymer nanocomposites were not fabricated with fully biobased polymers and thus, as per our knowledge, no reports were found on fully bio-based waterborne polyester/CNF nanocomposites.…”

Enhancing microfibrillated cellulose reinforcing efficiency in epoxy composites by graphene oxide crosslinking

“…Researchers have reported an extensive list of cellulosic materials that could potentially reinforce the polymeric matrices, including nanocellulose materials such as Microfibrillated Cellulose (MFC) or Cellulose Nanofiber (CNC), 5 Bacterial Cellulose (BC), 6 Cellulose Nanocrystals (CNC), 7,8 Cellulose Nanowhisker 9,10 and some micro-sized fillers including wood flour 11,12 and plant derived fibers etc. [13][14][15][16][17] Micro-sized fillers usually contain large amounts of non-cellulosic components like lignin and hemicellulose, 18 which result in relative low mechanical properties of these fibers.…”