The current state-of-the-art strategy for making polymer colloids usually employs radical-initiated emulsion or miniemulsion polymerization. Despite its success, it has limitations: This strategy only works well with a limited number of monomers such as acrylates, methacrylates, and styrenics. It will break the double bonds of monomers, leaving no unsaturation in the polymer backbone (typically only side groups can be used for further functionalization). We challenged ourselves to address these issues via introducing metathesis chemistry into the preparation of polymer colloids. Background Catalyst design (a) Further investigate the reactivity, efficiency and partitioning behavior of catalyst; (b) Deepen the understanding of kinetics in miniemulsion polymerization including nucleation, chain propagation, chain transfer, etc.; (c) Introduce new monomers. Experimental Future Work Motivation Experimental Polymer Latexes via Ring-opening Metathesis Polymerization (ROMP) Chunyang Zhu 1 , Xiaowei Wu 2 , Cathleen M. Crudden 2 , Michael F. Cunningham 1,2 1. Department of Chemical Engineering, Queen’s University, Kingston, Ontario, Canada, K7L 3N6 2. Department of Chemistry, Queens’s University, Kingston, Ontario, Canada, K7L 3N6 [1] Hong, S. H., & Grubbs, R. H. (2006). Journal of the American Chemical Society, 128(11), 3508–9. Ontario Research Chairs Program Why ring opening metathesis polymerization (ROMP)? Traditional radical polymerization methods result in a reduction in functionality (alkenes to alkanes). In contrast, ROMP retains all of the functionality of the starting olefins, which allows potential applications in many fields such as biomaterials, liquid crystalline polymers, self-healing materials, degradable plastics, and nanocomposites. How does ROMP work in the aqueous phase? Current ROMP is typically employed in organic solvents since the catalysts are hydrophobic and have limited long-term stability in water.[1] Here we developed a novel ROMP process in aqueous dispersions which eliminates the use of organic solvents and enhances heat transfer and mixing. This new process is based on our modified catalysts. The development is believed to achieve three objectives: (a) Enabling the preparation of latexes via ROMP, which is currently not possible in industry; (b)Eliminating the use of large amounts of volatile organic compounds (VOCs); (c) Improving the efficiency and lowering the cost of the manufacturing process. (a) A novel water-soluble metathesis catalyst was customized for miniemulsion polymerization. (b) A procedure was developed for ring opening metathesis polymerization in miniemulsion. (c) Well-defined polymer latexes were obtained with stable colloidal behavior and particle size, which can be used as intermediates for further modification. After shaking Solubility Stability Reactivity 1 H NMR of new catalyst (D 2 O) 1 H NMR of ROMP (CD 2 Cl 2 ) Kinetic study LnM R me t a l a lkylid ene + LnM R [ 2 + 2 ] LnM R LnM R me t a ll ac y c l o b u t ane LnM R + n LnM R n+ 1 LnM R n+ 1 + X = Y LnM = X Y R n+ 1 + I n iti a ti on: P ro p a g a ti on: T erm i na ti on: = − = ln 0 = ln 1 1 − = Preparation of monomer miniemulsion HD/COD/Triton-X100/H 2 O Time (min) 0 10 20 30 40 50 60 70 Z-avg (d. nm) 50 100 150 200 250 PDI 0.0 0.1 0.2 0.3 0.4 0.5 HD/COD/CTAB/H 2 O Time (min) 0 10 20 30 40 50 60 70 Z-avg (d. nm) 60 80 100 120 140 160 180 200 PDI 0.0 0.1 0.2 0.3 0.4 0.5 HD/NB/Triton-X100/H 2 O Time (min) 0 10 20 30 40 50 60 70 Z-avg (d. nm) 50 100 150 200 250 PDI 0.0 0.1 0.2 0.3 0.4 0.5 HD/NB/CTAB/H 2 O Time (min) 0 10 20 30 40 50 60 70 Z-avg (d. nm) 60 80 100 120 140 160 180 200 PDI 0.0 0.1 0.2 0.3 0.4 0.5 LogM 3.6 3.8 4.0 4.2 4.4 4.6 4.8 5.0 5.2 5.4 d(wt)/d(LogM) 0.0 0.5 1.0 1.5 2.0 2.5 3.0 Conversion 0.0 0.2 0.4 0.6 0.8 1.0 Mn 0 10000 20000 30000 40000 50000 60000 PDI 1.0 1.2 1.4 1.6 1.8 2.0 2.2 2.4 t = 1 hr t = 2 hr t = 3 hr t = 4 hr t = 5 hr t = 7 hr t = 12 hr ROMP in miniemulsion Ar Ar H 2 O/Surfactant Monomer/costabilizer Ar Monomer miniemulsion Sonication Catalyst Ar Polymer latex cannula cannula Monomer emulsion Time (hr) 0 20 40 60 80 Z_avg (nm) 100 120 140 160 180 200 PDI 0.0 0.1 0.2 0.3 0.4 0.5 Discussion References ROMP of 1,5-cyclooctadine in CD 2 Cl 2 using the new catalyst. Evolution of molecular weight and PDI with conversion (solution polymerization). Z-average diameter and PDI values of various monomer miniemulsions. ROMP in miniemulsion with air-free technique. Evolution of MWD, Mn and PDI with reaction time (miniemulsion polymerization). Z-average diameters during polymerization. [ R u ] n n Time (hr) 0 20 40 60 80 Conversion 0.0 0.2 0.4 0.6 0.8 1.0 Time (hr) 0 20 40 60 80 ln[1/(1-x)] 0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 Conversion 0.0 0.2 0.4 0.6 0.8 Mn 0.0 2.0e+4 4.0e+4 6.0e+4 8.0e+4 1.0e+5 1.2e+5 PDI 0 1 2 3 4 Mn Target Mn PDI LogM 3.5 4.0 4.5 5.0 5.5 6.0 6.5 dwt/dLogM 0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 60 h 48 h 36hr 24 h 12 h Conversion and normalized conversion plots with time (miniemulsion polymerization). O O O OH O O N N B r O O O Prof. Crudden Prof. Cunningham Chunyang Zhu Dr. Wu