GEORGIA INSTITUTE OF TECHNOLOGY

Under the provisions of the regulations for the degree

DOCTOR OF PHILOSOPHY

on Wednesday, May 18, 2022

12:00 PM

via

BlueJeans Video Conferencing

https://bluejeans.com/4142944177

will be held the

DISSERTATION DEFENSE

for

Monica Marks

"Quaternary Ammonium Cation Bis-MPA Dendron PDMS Hybrid Copolymers: Synthesis, Characterization, Behavior and Functional Use as Macromolecular Additives in Sylgard 184”

Committee Members

Prof. Mark Losego, Co-Advisor, MSE
Prof. Mary Lynn Realff, Co-Advisor, MSE
Prof. Julie Champion, ChBE
Prof. Natalie Stingelin, ChBE/MSE
Anita Mizusawa, PhD, Toray Advanced Composites

Abstract:

This work aims to address the research question: Can quaternary ammonium cation dendron-PDMS hybrid copolymers be utilized as surface active macromolecular additives in Sylgard 184? 

In attempts to answer this question several steps were taken:
 

• Synthesis of a library of quaternary ammonium cation (QAC) small molecule zwitterion building blocks of different hydrophobicity (alkyl chain lengths C₄, C₈, C₁₂, C₁₆) 
• Synthesis of a library of QAC bis-MPA dendrons of different branching (G1, G2 G3, G4) and different hydrophobicity (C₄, C₈, C₁₂, C₁₆) using esterification chemistry 
• Synthesis of a library of QAC bis-MPA dendron-PDMS hybrid copolymers of different branching (G1, G2 G3, G4) and different hydrophobicity (C₄, C₈, C₁₂, C₁₆) using CuAAC “click” chemistry 
• Development of processing and cure conditions in order to incorporate the hybrid additives into Sylgard 184 

QAC bis-MPA dendrons were tested in solution for antimicrobial activity against gram negative E. coli, gram positive S. epidermidis and yeast S. cerevisiae. Preliminary surface testing was performed in combination with cure profile. In addition, dendron-PDMS hybrid behavior was probed via several physical characterization techniques. Ultimately, this work illustrates the first reported QAC bis-MPA type dendrons and their biocidal activity, the first reported dendron-PDMS hybrid copolymers and their behavior and preliminary studies displaying their potential use as surface active additives in Sylgard 184.