Synthesis of kenaf cellulose carbamate and its smart electric stimuli-response

• Cellulose carbamate particles are synthesized from kenaf core pulp.
• Electric stimuli-responsive electrorheological characteristics of cellulose carbamate are examined.
• Under an electric field, they show a phase change from fluid-like to solid-like.
• Yield stresses obtained demonstrate their typical ER characteristics.

Cellulose carbamate (CC) was produced from kenaf core pulp (KCP) via a microwave reactor-assisted method. The formation of CC was confirmed by Fourier transform infrared spectroscopy and nitrogen content analysis. The degree of substitution, zeta potential and size distribution of CC were also determined. The CC was characterized with scanning electron microscopy, X-ray diffraction and thermogravimetry analysis. The CC particles were then dispersed in silicone oil to prepare CC-based anhydrous electric stimuli-responsive electrorheological (ER) fluids. Rhelogical measurement was carried out using rotational rheometer with a high voltage generator in both steady and oscillatory shear modes to examine the effect of electric field strength on the ER characteristics. The results showed that the increase in electric field strength has enhanced the ER properties of CC-based ER fluid due to the chain formation induced by electric polarization among the particles.