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Kinetics on Acrylated Epoxideized Soybean Oil via RAFT . Spring 2014 Yuerui Huang. Motivation. Understand what factors will influent gel time Concentration AESO : Solvent 2, 3, and 4 Initial free radical concentration 0.2 and 0.5 ( ratio to CTA) Structure Different function Fun 4
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Kinetics on AcrylatedEpoxideized Soybean Oil via RAFT Spring 2014 Yuerui Huang
Motivation • Understand what factors will influent gel time • Concentration • AESO : Solvent • 2, 3, and 4 • Initial free radical concentration • 0.2 and 0.5 (ratio to CTA) • Structure • Different function • Fun 4 • Fun 2.61 • Fun 1 to 1.5 (summer plan)
RAFT • Mono-function • Equal probability • Linear polymerization • Pseudo 1st order reaction • Our system • Multi-function • Not equal probability • Not linear polymerization • Pseudo 1storder reaction?
Pseudo 1st order reaction • 1st order reaction • Pseudo 1st order reaction
Assumptions • Double bonds have equal probability to react • Pseudo 1st order reaction • Consider diffusion later • Consider structure effects later
Hypothesis • Ideal polymerization • Has same probability to react • Real situation • Do not have same probability to react
Diffusion effect • Easier to diffuse in dilute solution • Harder to diffuse in concentrate solution
Structure effect • In dilute solution, will have more structure effect • In concentrate solution, the structure effect is less
Procedure • Adding AESO, AIBN, CTA, and solvent in a flask • Purging Argon into the flash, in order to remove air • Put in 90°C oil bath, let the reaction begin • Sample taking • Determine the gel time • Vortex level decreases • Stir bar stops
Results '*' only one set has been done
Less solvent decrease gelation time dramatically and also decrease the gelation conversion. ----- reason: diffusion limit More solvent increase gelation time and also increase gelation conversion.
Log [M0/M] Time / min
Plan • GPC. Molecular weight vs conversion • Light Scattering-GPC/THFPolymer size. Radius of Gyration