Synthesis and Characterization of Polymerization-Powered Motor Systems

Open Access
Author:
McFadden, Timothy Ryan
Area of Honors:
Chemistry
Degree:
Bachelor of Science
Document Type:
Thesis
Thesis Supervisors:
  • Ayusman Sen, Thesis Supervisor
  • Raymond Lee Funk, Honors Advisor
  • Thomas E Mallouk, Faculty Reader
  • Barbara Jane Garrison, Faculty Reader
Keywords:
  • Nanomotors
  • Grubbs catalyst
  • ring-opening metathesis polymerization
  • enhanced diffusion
  • Janus particles
Abstract:
1 micron gold/silica particles have been modified by covalently binding Grubbs 1st and 2nd generation catalyst to the silica surface. The particles are capable of performing ring-opening metathesis polymerization of norbornene monomer to give polynorbornene. More interestingly though, the particles bearing these catalysts display enhanced diffusion when placed in a monomer solution. At 1 M norbornene, the Grubbs 2nd generation motor showed its highest increase in diffusion, a 70 % increase over the 0 M solution. GC analysis was conducted to determine the turnover frequency of the motor as a function of time and 1H NMR was used to determine the that the product of polymerization was polynorbornene. The synthesis of a dye-tagged Grubbs catalyst was also attempted to determine the diffusion coefficient for a single molecule during polymerization. The first step of the synthetic route was completed to give 1-(2,4,6-Trimethylphenyl)-1H-imidazole with a yield of 52 %. The products’ identity was confirmed with 1H NMR.