# Mechanical Properties of Micro/Nanocellulose-Filled Epoxy Sheets at Subzero and Elevated Temperatures

## TL;DR

This study examines how adding micro/nanocellulose to epoxy affects its mechanical and thermal properties at different temperatures.

## Contribution

The paper introduces a novel method of refining cellulose and evaluates its performance in epoxy composites under extreme temperatures.

## Key findings

- SMC_0_60_epoxy sheets showed the highest modulus across all tested temperatures.
- SMC_epoxy sheets had higher tensile strength than LVB_epoxy sheets due to nanocellulose fibrils.
- Filled epoxy sheets demonstrated 45–70% higher thermal conductivity and lower weight loss at 430 °C.

## Abstract

Due to their low
cost and 100% biodegradability, nanocellulose
fibrils derived from wood can serve as a filler in polymer sheets.
In this study, micro/nanocellulose fibrils were obtained after Lab
Valley beater (LVB) and Super masscolloider (SMC) refining. The LVB
refining was carried out for 20 min at 0 clearance (LVB_0_20), and
SMC refining was carried out for 60 min at 0.1 and 0 clearances (SMC_0.1_60
and SMC_0_60), and nonwoven sheets were fabricated using a vacuum
filtration. These micro/nanocellulose-filled epoxy nonwoven sheets
were processed by the hand layup/vacuum bagging and cured at 160 °C
for 3 h. The tensile properties of filled epoxy sheets were measured
at −20 °C, 23 °C, and 80 °C, and it was found
that the SMC_0_60_epoxy sheet revealed high modulus at all temperatures
compared to other sheets, but its strength and work-to-fracture values
are found to be low at 80 °C compared to −20 °C.
SMC_epoxy sheets have high tensile strength compared to LVB_epoxy
sheets due to the presence of nanocellulose fibrils. The tensile fractography
was carried out using SEM. Filled epoxy sheets revealed 45–70%
higher thermal conductivity and slightly lower weight loss at 430
°C compared to epoxy, making these sheets useful in developing
optimum strength and partially biodegradable thermal packaging components.