ADVANCING BIOCOMPOSITES: INTRODUCTION OF NANOCELLULOSE AS A SUSTAINABLE FILLER OF BIOBASED UNSATURATED POLYESTER RESINS

Abstract

Biocomposites are materials that are composed of a matrix and fillers both of which derived from renewable resources. They offer an alternative to traditional petroleum-based composites and have gained interest due to potential environmental benefits and sustaina idea, itaconic and succinic acids and propylene glycol were used in the synthesis of a biobased unsaturated polyester, diluted with biobased reactive diluent, dimethyl itaconate, to cure fully biobased unsaturated polyester resin (UPR). Despite having a low environmental impact, the mechanical properties of biobased UPRs are not considered commercially viable compared to their petroleum-based counterparts. To lessen the discrepancy between the two, nanocellulose (NC) was incorporated into the biobased UPR in two ways. Firstly, NC was added during synthesis, while secondly it was added after the synthesis of UPR was completed. Both series implied the use of three different quan s of NC (1, 2, 3 wt.%). FTIR spectroscopy, gel content analysis, SEM, dynamic mechanical analysis, and uniaxial tensile test were used to characterize obtained biocomposites. It was demonstrcted that when NC was added during the synthesis, it had no effect on UPR viscosity. On the other hand, adding NC after the synthesis significantly increased viscosity. Overall results showed that higher quantities of NC increased tensile strength, storage modulus at lower frequencies, and decreased glass transition temperature.