Degree Type
Thesis
Date of Award
2017
Degree Name
Master of Science
Department
Agricultural and Biosystems Engineering
Major
Agricultural and Biosystems Engineering
First Advisor
David Grewell
Abstract
This research focuses on the characterization of bioplastics joined using ultrasonic welding and modeling of temperature distributions and interfacial healing. Polylactic acid (PLA), which is typically derived from starch-rich crops such as corn, was studied. While the measurement of activation energy for interfacial healing at weld interfaces of PLA films has been reported, here, this information is used to predict the weld strength of rigid PLA samples welded by ultrasonics. A characterization of the mechanical properties was completed with a tensile test to determine the effects of amplitude, melt velocity and collapse distance on weld strength. From previous interfacial healing activation energy measurements based on an impulse welding method, it was also possible to predict weld strength.
It was found that the most influential parameters were weld time, collapse distance and weld velocity. In general, the model predicted weld strength reasonably well with r2 values between 0.77 and 0.78.
DOI
https://doi.org/10.31274/etd-180810-5790
Copyright Owner
Karla Enid Lebron
Copyright Date
2017
Language
en
File Format
application/pdf
File Size
67 pages
Recommended Citation
Lebron, Karla Enid, "Interfacial healing and transport phenomena modeling of biopolymers" (2017). Graduate Theses and Dissertations. 16161.
https://lib.dr.iastate.edu/etd/16161
Included in
Agriculture Commons, Bioresource and Agricultural Engineering Commons, Materials Science and Engineering Commons, Mechanics of Materials Commons
