Hybrid Fiber-Reinforced Green Composites
Rice straw is considered as one of major agricultural wastes in the world. Nearly 800 million tons of rice straw are generated annually worldwide [1]. The purpose of this project is to transform unwanted rice straw left on the paddy fields into value materials for practical medium-strength applications.
Fabrication
Raw rice straw was alkaline treated before preparing fiber mats. This process is followed by impregnating the fiber mat in soy-based resins. Each composite lamina was oven-dried and steamed before hot-pressed to form a composite laminate.
Soy-based Composite Panels
Rice straws were treated at different alkaline conditions to access resin-fiber bonding
Varieties of Composite Panels
The composites were made of pure soy protein, corn starch, or blended resins
Corrugated Composite Panels
Depending on the hot-pressing die designs, complex structure of corrugated composites can be achieved
Testing
Physical tests (swelling, density, and moisture) and mechanical tests (tensile, 3-point bending, and screw) were conducted to access the composites' physical and mechanical properties.
Hot-press Design
3D AutoCAD modeling vs the demo of the hot-press design
Autocad 3D design of a corrugated hot-pressing die
Physical designed parts made of aluminum
Corrugated die in use
Corrugated panel
Orthogonal Corrugated Panel
Multiple flat aluminum bars (0.15" x 0.3" x 10") were placed orthogonal to the previous set
Hot-press the orthogonal corrugated panel
Autocad 3D design of one-pressed corrugated die
Autocad 3D design of an adhesion test
Physical designed parts made of aluminum
One-pressed die in use
Corrugated composites made via the one-pressed corrugated die
Autocad 3D design of a lap shear test
Lap Shear Specimen
Lap Shear Test
Adhesion Test
References
[1] B. Gadde, C. Menke, and R. Wassmann, “Rice straw as a renewable energy source in India, Thailand, and the Philippines: Overall potential and limitations for energy contribution and greenhouse gas mitigation,” Biomass and Bioenergy, vol. 33, no. 11, pp. 1532–1546, Nov. 2009, doi: 10.1016/j.biombioe.2009.07.018.
[2] B. Gadde, S. Bonnet, C. Menke, and S. Garivait, “Air pollutant emissions from rice straw open field burning in India, Thailand and the Philippines,” Environmental Pollution, vol. 157, no. 5, pp. 1554–1558, May 2009, doi: 10.1016/j.envpol.2009.01.004.
Master Thesis
Self-healing Green Thermoset Resins Toughened with Electrospun Epoxidized Natural Rubbers
Cross-linked Thermoset Soy Protein Isolates (SPI) Resins
Mechanical properties and moisture resistance of soy protein resins can be improved significantly by cross-liking soy protein chains with Cinnamaldehyde cross-linkers to form SPI thermoset resins.
Elongated Microcapsule Synthesis
Elongated microcapsules (MCs) are hypothetically more efficient in healing thermoset resins than the spherical microcapsules. Given their high aspect ratio, it is highly probable that the elongated MCs are in the crack paths, which is the main mechanism that ruptures MCs, releases SPI healants, and finally self-heals the resins. Elongated MCs in this study were fabricated via the double emulsion solvent evaporation (ESE) method along with a surface active molecules, sodium tripolyphosphate.
There are two parameters that mainly govern the shape of the microcapsules: the concentration of the aqueous phase surfactant PVA and the concentration of the surface active molecules STP.
8% ENR-50
Electrospun Epoxidized Natural Rubber (ENR-50) Fibers
Electrospinning Setup
5 % ENR-50
10 % ENR-50
8 % ENR-50
12 % ENR-50
Self-healing Green Thermoset SPI Resins
Fixture Design for Crack Test
Senior Design Project
Ultra High Temperature Direct Bonding of Sapphire Fiber to Alumina Substrate for Optical Sensing Applications
