Utilization of Microfibrillated Cellulose as a Filler in Adhesive for Improvement of Mechanical–Thermal Performance and Biodegradation of Wood Pulp/PLA Laminate Biocomposite

• Published in: Journal of polymers and the environment 2024-04, Vol.32 (4), p.1741-1751
• Main Authors: Kadea, Suding, Kittikorn, Thorsak, Hedthong, Rattanawadee, Malakul, Ramitanun, Chumprasert, Sujin
• Format: Article
• Language: English
• Subjects: Biodegradation; Biomedical materials; Cellulose; Chemistry; Chemistry and Materials Science; Compatibility; Compatibilizers; Composite materials; Damping; Environmental Chemistry; Environmental Engineering/Biotechnology; Food packaging; Impact resistance; Industrial Chemistry/Chemical Engineering; Lamination; Materials Science; Mechanical properties; Original Paper; Polylactic acid; Polymer Sciences; Pulp; Soil testing; Spray coating; Tensile strength; Thermal analysis; Viscoelasticity; Weight loss; Wood; Wood pulp
• ISSN: 1566-2543; 1572-8919
• DOI: 10.1007/s10924-023-03055-x

Laminate biocomposites of wood pulp/polylactic acid (PLA) are produced using four types of adhesives as compatibilizers: PVA, PVA modified with 3-(trimethoxysilyl) propyl methacrylate (modified PVA), PVA with microfibrillated cellulose (PVA-MFC), and the modified PVA with MFC (modified PVA-MFC). Sheets of wood pulp were spray-coated with the compatibilizers and then laminated with PLA film. The lamination of PLA film and pulp sheet via spray coating of modified PVA was successful due to the improved compatibility of the components. Modified PVA could increase the tensile strength of the laminate biocomposite by up to 25% compared with unmodified PVA. Additionally, the incorporation of 5 wt% of modified PVA-MFC improved the impact resistance of the laminate biocomposite by 195% while surface polarity was reduced by almost 85%. Dynamic mechanical thermal analysis (DMTA) of viscoelastic properties revealed the plasticizing effect of MFC in modified PVA. Modified PVA-MFC best promoted the damping factor of the laminate biocomposite. A soil burial test showed that modified PVA-MFC also had the greatest effect on the biodegradation of the laminate biocomposite with a weight loss of 50% after six months. Our study indicated that the laminate biocomposite compatibilized with modified PVA-MFC (5 wt% dry mass of MFC in modified PVA) exhibited better mechanical properties and biodegradation than the other studied biocomposites and was more suitable for use as degradable food packaging. Graphical Abstract