Extraction and surface modification of cellulose fibers and its reinforcement in starch-based film for packaging composites

Abstract

Background Cellulose extraction from gloss art paper (GAP) waste is a recycling strategy for the abundance of gloss art paper waste. Here, a study was conducted on the impact of ultrasonic homogenization for cellulose extraction from GAP waste to improve the particle size, crystallinity, and thermal stability. Results At treatment temperature of 75.8 °C, ultrasonic power level of 70.3% and 1.4 h duration, cellulose with properties of 516.4 nm particle size, 71.5% crystallinity, and thermal stability of 355.2 °C were extracted. Surface modification of cellulose GAP waste with H3PO4 hydrolysis and 2,2,6,6-tetramethylpiperidine-1-oxyl radical (TEMPO) oxidation was done followed by starch reinforcement. Surface hydrophobicity and mechanical strength were increased for H3PO4 hydrolysis and TEMPO oxidation starch–cellulose. No reduction of thermal properties observed during the treatment, while increment of crystallinity index up to 47.65–59.6% was shown. Neat starch film was more transparent, followed by starch–TEMPO film and starch–H3PO4 film, due to better homogeneity. Conclusions The cellulose GAP reinforced starch film shows potential in developing packaging materials and simultaneously provide an alternative solution of GAP waste recycling. Graphical Abstract

Microwave-plasma induced one-step synthesis of Ni(PO3)2 nanosphere-loaded bio-waste derived N, P co-doped carbon for an asymmetric supercapacitor with prolonged life

“…The TGA curve of NPGC@1 : 1 (Fig. 2f) shows an initial weight loss of ∼3.0% within 200 °C (which may correspond to the removal of moisture), then a second weight loss of ∼5.0% within 470–490 °C (which may be related to the removal of hydroxyl groups or other volatile substances attached to the surface), 47 and finally, a major weight loss of ∼88.5% (due to the decomposition of carbonaceous mass) up to 820 °C, and then become stable up to 900 °C. NPGC@1 : 1 also contains 11.5% of residue generated on the microwave processing of the bio-waste coffee grounds.…”