Biobased Composites Prepared by Compression Molding with a Novel Thermoset Resin from Soybean Oil and a Natural-Fiber Reinforcement

Biobased composites were manufactured with a compression-molding technique. Novel thermoset resins from soybean oil were used as a matrix, and flax fibers were used as reinforcements. The air-laid fibers were stacked randomly, the woven fabrics were stacked crosswise (0/90 degrees), and impregnation was performed manually. The fiber/resin ratio was 60 : 40. The prepared bio-based composites were characterized by impact and flexural testing. Scanning electron microscopy of knife-cut cross sections of the specimens was also done to investigate the fiber-matrix interface. Thermogravimetric analysis of the composites was carried out to provide indications of thermal stability. Three resins from soybean oil [methacrylated soybean oil, methacrylic anhydride modified soybean oil (MMSO), and acetic anhydride modified soybean oil] were used as matrices. The impact strength of the composites with MMSO resin reinforced with air-laid flax fibers was 24 kJ/m(2), whereas that of the MMSO resin reinforced with woven flax fabric was between 24 and 29 kJ/m(2). The flexural strength of the MMSO resin reinforced with air-laid flax fibers was between 83 and 118 MPa, and the flexural modulus was between 4 and 6 GPa, whereas the flexural strength of the MMSO resin reinforced with woven fabric was between 90 and 110 MPa, and the flexural modulus was between 4.87 and 6.1 GPa. (C) 2010 Wiley Periodicals, Inc. J Appl Polym Sci 716: 1759-1765, 2010