*********************************
There is now a CONTENT FREEZE for Mercury while we switch to a new platform. It began on Friday, March 10 at 6pm and will end on Wednesday, March 15 at noon. No new content can be created during this time, but all material in the system as of the beginning of the freeze will be migrated to the new platform, including users and groups. Functionally the new site is identical to the old one. webteam@gatech.edu
*********************************
MSE PhD Defense - Seth Young
Date: Tuesday, December 15th 2015
Time: 1:00 PM
Location: Molecular Science and Engineering Building (MoSE) 1226
Title: Atomic force microscopy probing methods for soft viscoelastic synthetic and biological materials and structures.
Committee:
Prof. Vladimir V. Tsukruk Advisor, MSE
Prof. Ken Gall, ME/MSE, Duke University
Prof. Andres Garcia, ME
Prof. Jeffrey Streator, ME
Prof. Jeannette Yen, Bio
Abstract:
Mechanical properties of micro- and nanoscale viscoelastic soft materials can dictate their performance and function. In this dissertation we focus on refining atomic force micrscopy (AFM) methods and data analysis routines to measure the viscoelastic mechanical properties of soft polymer and biological materials in relevant fluid environments and in vivo using a range of relevant temperatures, applied forces, and loading rates.
These methods are directly applied here to a several interesting synthetic and biological materials. First, we probe poly(n-butyl methacrylate) (PnBMA), above, at and below its glass transition temperature in order to verify our experimental procedure. Next, we use AFM to study the viscoelastic properties of coating materials and additives of silicone-based soft contact lenses in a tear-like saline solution. Finally, a major focus in this dissertation is determining the fundamental mechanical properties that contribute to the excellent sensitivity of the strain sensing organs in a wandering spider (Cupiennius salei) by probing under in vivo conditions.
These strain-sensing organs are known to have a significant viscoelastic component. Thus, the cuticle of living spiders is directly investigated in near-natural environments (high humidity, temperatures from 15-40 °C).