Discipline: Technology and Engineering
Subcategory: Materials Science
Vertonica Powell-Rose - Tuskegee University
Co-Author(s): Mahesh Hosur and Alfred Tcherbi-Narteh, Tuskegee University, AL
Composites made by natural fibers and biopolymers are completely biodegradable and are called ‘green composites’ because of their environmentally beneficial properties. The lower price in manufacturing as well as the better performance of traditional, petrochemical plastics compared to polymers based on natural resources are the outcomes of the research efforts of several decades. Natural fibers are lightweight and bio-renewable; with low-cost and comparable specific strength compared to synthetic counterpart. For these reasons, natural Science and fiber composites have already been used for fabricating some products such as furniture and architectural components. Recently, they have gained widespread use in the automobile industry. In the current study, three different types of nanoclay was infused into bio-based epoxy system and used in fabricating natural fiber based composites. Flax fiber mat treated with potassium hydroxide (KOH) and 3-aminopropyltriethory silane was used in the fabrication of bio-nanocomposites and mechanical and thermal properties characterized. Differential scanning calorimetry (DSC) thermogravimetric analysis (TGA) and dynamic mechanical analysis (DMA) were used to characterize these materials and compared to control samples fabricated without treating the fibers and with no nanoclay. Nanoclay infused epoxy and surface modified fibers displayed improvements in storage modulus compared to untreated fiber/modified epoxy system. Biodegradability studies on these samples in a composting environment with a 50/50 carbon to nitrogen ratio exhibited an initial weight gain during the first few weeks. After week two there was a decrease in the thermal decomposition peak temperature which extended until week four. The thermal decomposition remain constant for the rest of the exposure period (week eight). This is evident for that the next break down in material would need longer exposure time. The scanning electron microscope (SEM) shows evidence of voids developing in the sample after weeks of exposure. During this type the moisture, temperature and C/N ratio remain fairly constant, displaying that the breakdown of samples did not affect the environment around it.
Funder Acknowledgement(s): Authors are grateful to the NSF-CREST (grant no. 1137681) and NSF-EPSCoR (grant no. 1158862) for the financing support to carry out this research.
Faculty Advisor: Mahesh Hosur, email@example.com
Role: I did all of the research myself. I fabricated all the composites. I did the testing and analysis of the data. I also monitored the decomposition study.