Synthesis of pine needle cyanoethyl cellulose using Taguchi L25 orthogonal array

Functionalization of cellulose has been emerging as an innovative approach toward fundamental issues for sustainable utilization of renewable materials. In order to comply with global environmental regulations, it will be beneficial to convert waste biomass into useful materials without generating pollutants. This study aims to develop an effective technique for utilizing Pinus roxburghii Sarg. needles to synthesize a papermaking strength additive. An attempt was made to synthesize pine needle cyanoethyl cellulose (PNCEC) in an etherification reaction by using Taguchi's L25 orthogonal incomplete array with a target of obtaining a higher degree of substitution (DS). Assessment of optimal conditions, for the synthesis of pine needle cyanoethyl cellulose (PNCEC), was done by the application of signal/noise ratio (SNR) method. A maximum DS value of 2.67 was obtained under optimized reaction conditions after examining the effects of each reaction parameter. FT-IR, 1H NMR confirms the functionalization of pine needle alpha-cellulose (PNAC) to PNCEC. X-ray diffraction (XRD), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and scanning electron microscopy (SEM) further confirmed the crystalline behavior, thermal stability and surface morphology of PNCEC. The application and effect of cyanoethyl cellulose as strength additive were also studied in paper making. An evaluation of the mechanical strength of laboratory handsheets was conducted, including tear index, tensile index, and burst index. These results interpret that the addition of PNCEC can enhance up to 25.5 % physical strength of paper. Hence, instead of using synthetic additives, PNCEC can be utilized to enhance the physical strength properties of paper.