RAFT Polymerization of Styrene and AcrylatedExpoxidized Soy Bean Oil of Various Functionalities. By: Lucas Dunshee
Outline • Group Main Goal • My Main Goal • Theory/Background • Results • Future Directions • Conclusion
Group Main Goal/Objective • To produce durable, thermoplastic polymers, and elastomers from bio-renewable resources. • This is done by the RAFT and ATRP polymerization methods. • As an example, butadiene is a common chemical derived from petroleum based methods, that can be used in block co-polymers. Butadiene's cost is known to be more expensive than bio-renewable products such as soybean oil. • Our project aims to replace petroleum based products such as butadiene. Not only is this environmentally efficient, but is also cost effective.
My Main Goal/Objective • 1) Become familiar laboratory procedures and experiments for RAFT polymerization. • -Polystyrene & CTA Homopolymer Synthesis • -Conversion of ESO to ASO with various functionalities (1, 2, 3, and 4) • -Di-Block Synthesis • -Tri-Block Synthesis • 2) Learn how to utilize common laboratory equipment. • -Filter Column (with Silica Gel and Alumina) -Compressed gas cylinder • -Rotary Evaporator • -Vacuum Oven • -H-NMR • -GPC • 3) Characterize products via GPC and H-NMR of: • a) Homopolymer Styrene • b) AESO functionality four and one • c) Di-Block Polymer (primarily function 1 and 4) • d) Tri-Block Polymer (primarily function 1 and 4)
Theory/Background • Copolymers- Polymers with two or more individual monomers that are representative in a single polymeric macromolecule. • Block Copolymers – A type of copolymer that forms “blocks” of the different types of monomers. Usually block polymers are either Di-Block (Two Polymers) or Tri-Block (Three Polymers) as observed in the figure below. Monomer Series A Monomer Series B Di-Block Polymer Tri-Block Polymer Figure 1: Depiction of Di-Block and Tri-Block Copolymers.
Theory/Background • RAFT Polymerization –stands for, Reversible Addition-Fragmentation chain-Transfer polymerization. • The basics of this technique utilize a free radical initiator and a radical chain transfer reagent (usually a thio carbonyl thio molecule). Figure 2: Basic roles of RAFT reagent and Initiator.
Results 1) Polystyrene Synthesis Figure 3: NMR result peaks of Styrene Homopolymer, note the unreacted styrene peaks.
Results 1) Polystyrene Synthesis • -Mn= 18,636 g/mole as determined by GPC • -PDI = 1.05 Figure 4: NMR result peaks of Styrene Homopolymer, note that there are no longer unreacted styrene peaks present.
Results 1) Polystyrene Synthesis • -Mn= 18,636 g/mole as determined by GPC • -PDI = 1.05 Figure 5: GPC result of Styrene Homopolymer.
Results 1) AESO Function one Synthesis Indication of unreacted Acrylic Acid. Figure 6: NMR result peaks of AESO function one with unreacted acrylic acid.
Results 1) AESO Function one Synthesis • -Functionality = 1.12 • -Functionality is determined from the following NMR peaks shown below with arrows. The peak on the right is normalized to 9, and the peaks on the left are averaged and referenced to that number, allowing for the calculation of the functionality. Figure 7: NMR result peaks of AESO function one with no unreacted acrylic acid.
Results 1) AESO Function four Synthesis -Functionality = 3.8 -Similarly this is done for AESO function four as well. Figure 8: NMR result peaks of AESO function four.
Results 1) Di-Block Synthesis (AESO function four) -PDI = 2.12-Mn = 164,427 Figure 9: GPC result of Di-Block, PS with AESO function four.
Results 1) Di-Block Synthesis (AESO function one) -PDI = 1.685-Mn = 212,956 Figure 10: GPC result of Di-Block, PS with AESO function one.
Future Directions and Conclusion Future Directions: -Successfully Synthesize AESO with functionalities 2 and 3. -Determine the best ratios of reagents (specifically Acrylic Acid), that precisely yields AESO function one with a functionality within 10%of 1.00 -Successfully Synthesize Tri-Block Polymer with AESO functionality of one. -Compare properties of Tri-Block AESO functionality one with Tri-Block AESO functionality four. Concluding Remarks- -Became familiar with polymer synthesis procedures -Learned how to utilize lab equipment in order to synthesize polymer -Characterized products via H-NMR and GPC
Supplemental Information: Materials and Methods -Synthesis of Styrene Homopolymer • Reagents Needed: Monomer Styrene, Dioxane (solvent), Azobisisobutyronitrile (AIBN), Chain Transfer Agent (CTA); all of which can be purchased from chemstores in Gilman Hall. • Additional Materials Needed: Gas Cylinder of Argon, Silica Gel, Aluminum Oxide, Glass Column, Round Bottom Flask, Stir Bar, Needles, Rotary Evaporator, Liquid Nitrogen, Methanol, Ethanol, Beaker, Vacuum Oven.