MCC (25 g) was dispersed in toluene (250 mL) and stirred for 1.5 h at ambient temperature. Appropriate amounts of coupling agent were added to achieve a concentration of 1% v/v. The solution was subjected to ultrasonic disruption to ensure fibres were completely coated with coupling agent (Autotune Series – High Intensity Ultrasonic Processor with temperature controller, model CV33). Fibres were disrupted for 10 min at 21 °C, with a frequency of 20 kHz. The toluene was evaporated under ambient conditions. The treated MCC was dried in a vacuum oven for 1 h at 100 °C to remove any residual solvent. Dried samples were stored in a desiccator (0% relative humidity).