Date of Thesis
Bachelor of Science in Chemical Engineering
As the global supply of petrochemicals diminishes, the polymer industry will need to incorporate renewable resources into the production process. Acrylated expoxidized soybean oil, a modified plant oil, is one possible candidate for use as a monomer in plastics. When polymerized alone, AESO creates a fairly unusable polymer, with poor physical and material properties. To improve the properties, the monomer can be copolymerized with styrene and other additives and can be incorporated into a composite to further increase the usability. By using biorenewable fillers, the overall use of nonrenewable materials in the composite can be further decreased. In this research, composites consisting of a 50:50 AESO:styrene copolymer matrix and either pecan nut shell flour (PNSF), egg shell calcium (ESC), or organically modified clay (OMC) were created and their physical properties analyzed. AESO and styrene were successfully polymerized into a cohesive copolymer, with greater amounts of AESO producing copolymers that were softer and more rubbery. Higher amounts of AESO generally led to a decrease in stiffness, strength, and hardness, while increasing the flexibility. The brittleness of the material decreased as the amount of AESO increased. Thermal analysis revealed that higher AESO contents resulted in lower thermal stability and glass transition temperatures, but increased the amount of crosslinking within the copolymer. The addition of the fillers generally improved the properties of the composite. The stiffness and hardness both improved as filler content increased; however, the brittleness, strength, and flexibility all worsened. All of the fillers achieved good dispersion within the composite and maintained low particle sizes at high loadings. The fillers did not improve the thermal stability of the composite, nor did they degrade it any further. Of the fillers tested, egg shell calcium (ESC) produced the greatest improvement to the mechanical properties and could achieve the highest loadings. Future work should continue to analyze the effect of blend composition on copolymer, as well as investigate the use of bonding agents to improve filler-matrix cohesion.
Fox, Andrew Jacob, "Synthesis and Properties of Acrylated Epoxidized Soybean Oil Copolymers and Their Composites with Natural Fillers" (2016). Honors Theses. 345.