Wetting and localization of compatibilizers in biocomposites: A nanoscale evaluation and effects on physical properties. (17th December 2019)

• Record Type: Journal Article
• Authors: Niwa, Saori; Ogawa, Tatsuya; Ogoe, Shinji; Teramoto, Yoshikuni
• Is Part Of: Polymer. Volume 185(2019)
• Publication Date: 2019-12-17
• Subjects: Maleic anhydride-modified polypropylene -- Cellulose -- Interface/interphase; Polymers -- Periodicals; Polymerization -- Periodicals; Polymères -- Périodiques; Polymérisation -- Périodiques; 547.7
• DOI: 10.1016/j.polymer.2019.121963
• Languages: English
• ISSNs: 0032-3861

Abstract

Abstract: To elucidate the efficacies that have been empirically interpreted on compatibilizers, the interfacial adhesion in cellulosic filler/polypropylene (PP) biocomposites was investigated at the nanoscale. Maleic anhydride-modified PP (MAPP) with different weight fractions ( w MA ) of acid-modified groups was added as the compatibilizer. Two nanoscale aspects were examined: the degree of wetting of the compatibilizer on the microcrystalline cellulose (MCC) filler and the extent of compatibilizer localization. The degree of wetting was systematically evaluated via differential scanning calorimetry and was found to increase with w MA . Transmission electron microscopy revealed that MAPP was located near MCC particles in MCC/MAPP/PP composites via thermal kneading, while only a part of the loaded MAPP was localized at the of MCC/PP interface. The MAPP layer thickness was ~50 nm and independent of w MA . The increased degree of wetting with increasing w MA improved the rheological reinforcement effect, the withdrawal of MCC filler on the fracture surface, and the mechanical properties. Thus, MCC was probably tightly coated with the MAPP with high w MA and the interfacial tension with the PP matrix was decreased. Graphical abstract: Image 1 Highlights: Maleic anhydride modified PP (MAPP) as a compatibilizer. DSC estimated cellulosic filler wetting by MAPP with different acid contents. TEM visualized MAPP localization at filler/PP matrix interface. MAPP with high acid content coated the cellulosic filler tightly. Physical properties of the composites were correlated with MAPP characteristics.