Thermal and Mechanical Properties of Polypropylene/Cellulose Nanofiber Composites

Abstract

Recently, one of the most abundant natural polymers in the earth, cellulose has been studied in various fields. In this study, polymer composites were produced through introduction of cellulose nanofiber (CNF) into polypropylene (PP) which is one of the most commercially utilised polymer for enhanced mechanical properties. Also, maleic anhydride polypropylene (MAPP) was added to PP/CNF composites for compatibility improvement between non-polar PP and polar CNF. Both tensile strength and flexural strength were increased with the addition of CNF, but, on the other hand, impact strength was decreased. As a result of SEM analysis, the interaction between PP/MAPP matrix and CNF was created, and the tensile and flexural stress were influenced by the interaction between PP/MAPP matrix and CNF. Impact stress confirmed that it decreases by pore and stress concentration by CNF. The TGA analysis confirmed that composites are thermally unstable by CNF. Therefore, as CNF contents increased, the initial and final decomposition temperature of the composites are decreased. We also observed increase of porosity because of bound water in the case of high CNF contents.