Title
Eco-friendly composite fabricated from recycled waste paper and recycled polypropylene
Authors
JEVGENIJS JAUNSLAVIETIS, GALIA SHULGA, MARTINS KALNINS, JURIS OZOLINS, BRIGITA NEIBERTE, ANRIJS VEROVKINS, LAIMA VEVERE and TALRITS BETKERS

Received December 28, 2022
Published Volume 57 Issue 3-4 March-April
Keywords waste paper, microcrystalline cellulose, composite, contact angle, surface free energy, thermal stability, X ray diffraction

Abstract
The goal of the work was to recycle waste paper, utilize it as a filler and investigate the properties of the obtained recycled polypropylene-based composite. Crystalline cellulose from the waste paper was regenerated in accordance with the developed method in acid medium under mild conditions. The morphology, crystallinity degree, shape, and sizes of the obtained cellulose particles were characterized. It was found that the extracted crystalline cellulose contained more amorphous regions than the kraft pulp, and was characterized by a more hydrophilic structure. The extracted crystalline cellulose microparticles were used as a biofiller in the recycled polypropylene-based composite in its binary and ternary formulations, incorporating maleic anhydride-grafted polypropylene as an adhesion enhancer. The binary composite was characterized by unsatisfactory mechanical and wetting properties. The presence of the adhesion enhancer in the composite’s formulation improved the mechanical properties, increased the hydrophobicity and thermal stability of the composite.