Preparation and physical characteristics of epoxy resin/ bacterial cellulose biocomposites

• Published in: Polymer bulletin (Berlin, Germany) Germany), 2018-06, Vol.75 (6), p.2607-2625
• Main Authors: Le Hoang, Sinh, Vu, Cuong Manh, Pham, Lanh Thi, Choi, Hyoung Jin
• Format: Article
• Language: English
• Subjects: Biomedical materials; Carbon; Cellulose; Cellulosic resins; Characterization and Evaluation of Materials; Chemistry; Chemistry and Materials Science; Complex Fluids and Microfluidics; Composite materials; Coupling agents; Curing agents; Environmental impact; Epoxy resins; Ethanol; Flexural strength; Fracture surfaces; Fracture toughness; Graphene; High speed; Impact strength; Mechanical properties; Methods; Modulus of elasticity; Nanoparticles; Organic Chemistry; Original Paper; Physical Chemistry; Physical properties; Polymer Sciences; Polyvinyl alcohol; Renewable resources; Silanes; Soft and Granular Matter; Stirring; Tensile strength
• ISSN: 0170-0839; 1436-2449
• DOI: 10.1007/s00289-017-2162-4

Using bacterial cellulose (BC) prepared from Vietnamese nata-de-coco via an alkaline pre-treatment followed by a solvent exchange process, epoxy resin (EP)/BC biocomposites were fabricated using three different dispersion techniques: mechanical stirring only, both mechanical stirring and grinding, and both mechanical stirring and ultrasonication. The surface of BC was modified with a silane coupling agent to improve the chemical affinity between BC and epoxy resin. The biocomposite materials comprising BC, epoxy resin, and methylhexahydrophthalic anhydride as a curing agent were obtained from hot curing processing. The morphology and mechanical properties such as fracture toughness, enhanced K IC values, and tensile and flexural properties of the bio-based composites were compared with those of the virgin epoxy resin. The silane coupling agent had a vital role in improving the mechanical characteristics of the bio-based composites. For instance, K IC values, tensile strength, Young’s modulus, and flexural strength of the 0.3 wt% BC/epoxy composites with the presence of 2.0 wt% silane coupling agent were 0.7740 MPa m 1/2 , 53.32 MPa, 1.68 GPa, and 83.05 MPa. These values represent improvements of 36.77, 17, 15.86, and 14.42%, respectively, compared to a neat epoxy resin. Scanning electron microscopy revealed the rough fracture surface of epoxy resin/BC-based biocomposites with a multipathway crack, requiring more energy before breakage.