Two primary cost driving factors for the composites industry are raw materials and labor. Inexpensive alternative epoxy resin systems based on epoxidized soyate resins are developed for fiber reinforced composite applications. This research investigated on the manufacturing and mechanical characterization of fiber/epoxy composites using chemically modified soy-based epoxy resins. Co-resin systems with up to 30 wt% soyate resins were used to manufacture composites through pultrusion. Mechanical tests show that the pultruded composites with soy based co-resin systems possess comparable or improved structural performance characteristics such as flexural strength, modulus, and impact resistance. Maximum mechanical properties enhancement is demonstrated by the enhanced epoxidized allyl soyate (EAS) formulation. Further property improvement is obtained through using a two-step prepolymer process. The EAS holds great potential as partial supplement for polymer and composites applications from renewable resources.

Manufacturing and mechanical properties of soy-based composites using pultrusion

Described are the physical and chemical properties of the methyl esters of two uncommon fatty acids: vernolic acid, containing an epoxy group, and crepenynic acid, containing a triple bond. The incorporation of an epoxy or alkyne group into the fatty acid structure is shown to greatly affect the properties compared to conventional unsaturated fatty acids. The methyl esters have been characterized and compared with ordinary fatty acid methyl esters (i.e., methyl oleate and linoleate) with respect to spectroscopic characterization [1H nuclear magnetic resonance (NMR)], 13C NMR, and Fourier transform infrared), rheological properties, and oxidative reactivity (using chemiluminescence). Both methyl vernoleate and methyl crepenynate could successfully be produced by transesterification under basic conditions without reaction of the epoxy or alkyne groups. Rheological measurements showed that the methyl esters had a significantly lower viscosity compared to their triglyceride analogs. Smaller differences were seen when comparing the different methyl esters where methyl vernoleate had the highest viscosity due to the presence of the more polar oxirane group. Very large differences were found with respect to the oxidation rate of the different methyl esters. Methyl crepenynate was shown to oxidize extremely rapidly, whereas methyl vernoleate was very stable toward oxidation.

A study of fatty acid methyl esters with epoxy or alkyne functionalities

Polymer matrix composites using renewable resources are currently of great interest. A novel soy-based resin system for pultrusion was synthesized at University of Missouri-Rolla (UMR). Due to relatively low reactivity of soy-based resin and short curing time of pultrusion, it is important to set up the process parameters properly in order to obtain a high quality pultruded product. In the present work, a combination of experimental and numerical methods is used to investigate the effect of pultrusion process variables on the cure of composites. A mathematical model has been developed and implemented in the commercial ABAQUS finite element package to predict the temperature and degree of cure of soy-based composites. The kinetic parameters of the soy-based epoxy resins are obtained from a differential scanning calorimeter (DSC). Glass fiber-reinforced composite samples are manufactured using a pultrusion machine. For experimental verification, an online monitoring system is used to measure the temperature...

Cure Characterization of Pultruded Soy-based Composites

Polymer matrix composites using renewable resources are currently of great interest. A novel soy-based resin system for pultrusion was synthesized at University of Missouri-Rolla (UMR). Due to relatively low reactivity of soy-based resin and short curing time of pultrusion, it is important to set up the process parameters properly in order to obtain a high quality pultruded product. In the present work, a combination of experimental and numerical methods is used to investigate the effect of pultrusion process variables on the cure of composites. A mathematical model has been developed and implemented in the commercial ABAQUS finite element package to predict the temperature and degree of cure of soy-based composites. The kinetic parameters of the soy-based epoxy resins are obtained from a differential scanning calorimeter (DSC). Glass fiber-reinforced composite samples are manufactured using a pultrusion machine. For experimental verification, an online monitoring system is used to measure the temperature profiles inside the die. The degrees of cure of pultruded soy-based composites are measured by DSC. The experimental findings are in good agreement with the finite element prediction. The results indicate that the novel soy-based epoxy resin system is suitable for application in the pultrusion process.

Cure Characterization of Pultruded Soy-Based Composites

Conversion of an investment casting sprue wax to a pattern wax by the modification of its properties

Composite Prepared from Epoxidized Soybean Oil

Antimicrobial food packaging composite films prepared from hemicellulose/polyvinyl alcohol/potassium cinnamate blends.

Fiber Reinforced Composites from Epoxidized Soybean

Thermal insulation and antibacterial foam templated from bagasse nanocellulose /nisin complex stabilized Pickering emulsion.

Composite membranes were prepared from lignin alkali (LA), polyvinyl alcohol (PVA), and cellulose nanofibrils (CNF) using a simple, low-cost, and environmentally friendly method. The deodorization performances and structures of these membranes were also characterized. The sample referred to as L3C3P5 prepared with a solution containing 35.7 wt% LA, 53.6 wt% PVA, and 10.7 wt% CNF showed the best deodorization properties, and the H2S adsorption time reached 36 min. The adsorption performance was further improved by adding nano-CuO to the membrane, and the H2S adsorption time of the doped membrane L3C3P5C4 reached 60 min. While the H2S adsorption performance improved, structural analysis revealed that the addition of nano-CuO reduced the crystallinity in the membrane, caused the membrane to crack, and led to a decrease in the mechanical properties. The surface oxygens in the L3C3P5C4 membrane were primarily C-O bonds and lattice oxygens in CuO. After the H2S adsorption reaction, the lattice oxygen disappeared, and CuS products appeared.

Peng Peng Lu

Papers

Composite Prepared from Epoxidized Soybean Oil

Antimicrobial food packaging composite films prepared from hemicellulose/polyvinyl alcohol/potassium cinnamate blends.

Fiber Reinforced Composites from Epoxidized Soybean

Thermal insulation and antibacterial foam templated from bagasse nanocellulose /nisin complex stabilized Pickering emulsion.

Preparation and properties of lignin-based composite membranes.