Polymer Science Commons^™

Chloramine Devulcanization Of Waste Rubber., Patrick Kroeger

Electronic Theses and Dissertations

The disposal of waste rubber, particularly tire rubber, continues to pose a challenge in the 21st century. As a result, most end-of-life tires (ELTs) are either dumped in landfills or burned as tire-derived fuel. Chloramine devulcanization may offer a viable solution to this problem. Chloramine devulcanization is a low-temperature, low-pressure, process that selectively breaks sulfur crosslinks while preserving the polymer backbone. Chloramine devulcanization enables the recovery of chloramine recovered carbon black (CrCB) and devulcanized rubber (CdR) as separate products. Initial analysis of CdR revealed that it was formable and malleable, suggesting that crosslinking was absent. Spectroscopy showed that CdR contained …

Epoxy Curing: Paramount Or Trivial? A Cure Path Dependent Inquiry, Jared Bates

Dissertations

The presented research delves into epoxy network formation corroborating reactant concentration profiles and physical property development throughout cure, providing an experimental basis for burgeoning molecular dynamics and coarse-grained simulation methodologies. Herein, three primary subjects were investigated: the first two examine neat and toughened epoxide/amine network formation with respect to various cure profiles aimed at altering reaction pathways, the final chapter intends to augment traditionally utilized activation energy (E_a) methodologies.

Neat and toughened epoxide/amine slurries were monitored in-situ throughout cure via near infrared (NIR) spectroscopy and rheological techniques. Functional group conversion and moduli development were related with specific attention …

Evaluating Rubber Aging On Tire Durability: Quantitative Evaluation Of Rubber Aging, Brian Auffenberg

Williams Honors College, Honors Research Projects

Rubber is considered one of the most important polymers in the world due to its variety of uses. There are many different conditions that can affect the useful life of rubber. The purpose of this research was to determine how the mechanical loading on the rubber may affect the aging of the rubber. The scope of the project was to focus on the rubber used for tire production. The research was limited to focusing only on rubber supplied by industry mentors which was styrene-butadiene rubber. By varying the length of time for testing as well as the temperature of the …

Design Of Natural Rubber Extraction From Tks Dandelion, Jehad S. Alrawajfeh, Trevor Cody, Jason Pogozelski

Williams Honors College, Honors Research Projects

A design was developed for a controlled environment agriculture 3D greenhouse to grow and harvest TKS dandelions, as well as a processing plant to extract natural rubber and inulin from the roots. The design capacity was scaled for both pilot- and full-scale production: 100 and 100,000 tonnes of natural rubber per year, respectively. The byproducts of the process were dandelion greens, inulin, cellulose, and glucose; all of these except for cellulose were able to be valorized. The greenhouse was designed based on existing 3D hydroponic growing environments, and the extraction process was designed based on the original TKS dandelion extraction …

Understanding Rubber Friction In The Presence Of Water Using Sum-Frequency Generation Spectroscopy, Kumar Nanjundiah, Ping Yuan Hsu, Ali Dhinojwala

College of Polymer Science and Polymer Engineering

Infrared-visible sum-frequency-generation spectroscopy (SFG) was used to study the molecular structure of water between a poly(dimethylsiloxane) (PDMS) and a sapphire substrate. The observation of SFG peaks associated with the dangling surface hydroxyl groups (3690 cm(-1)) and water bands (3000-3400 cm(-1)) indicates that the contact spot between the PDMS lens and the sapphire substrate is heterogeneous. Within the contact spot there are regions where the methyl groups of the PDMS chains are in direct contact with the surface hydroxyl groups on the sapphire substrate. In the other regions, a thin water layer is trapped between the two surfaces with spectral features …