User:Anh Do/Notebook/CHEM 481 Polymer/2016/09/16

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Making beads using activated carbon instead of clay Making the solution of 2.5 g PVOH, 0.275 g activated carbon, and 30 mL HCl Mass of PVOH: 2.5005 g Mass of activated carbon: 0.2752 g Volumn of HCl: 30 mL Stir the solution at 400 rpm and heat it up at 85 degree celsius until everything dissolves Note: PVOH dissolves less readily in activated clay. Thus, the stirring speed and temperature needs to be increase. A wooden stick can also be used to Add 10 mL of this solution to a 50 mL solution of ethyl acetate stirring at 240 rpm in a dropwise manner using a burette. Initial: 31.3 mL Final: 41.3 mL Add 1 mL of glutaraldehyde and stir at 320 rpm for 3 minutes. Add 7 mL of sodium bicarbonate and stir for 3 minutes Remove the solution, put it into 2 50 mL Falcon tubes. Centrifuge the solutions for 1 minute at 3000 rpm twice. Make sure the two vials are of approximately the same mass Take out as much solution as possible from the vials, leaving only the beads inside Add water in the tubes, making sure they are of the same mass Centrifuge again Making beads using 20% clay Making the solution of 1.25 g PVOH, 10 mL of 3wt% clay, 13 mL 12.1M HCl, 30 mL of H2O Mass of PVOH: 1.2502 g Mass of clay: 1.25/4 = 0.3125 g Volumn of clay: 0.3125*100/3 ~ 10 mL Volumn of HCL: 13 mL (this is not a correct value) Place the solution on a hot plate at 70 degree celsius and stir at 300 rpm Repeat the procedure stated above Initial: 40.7 mL Final: 45.7 mL DSC Data (From Dominique's Notes) DSC Data Glass Transition (°C) Melting Point (°C) Heat of Melting (J/g) PVOH 70.25 191.13 35.66 PVOH x-link 80.07 179.67 0.6426 PVOH x-link 10% clay 82.19 168.08 0.5314 no glass transition, melting point, or heat of melting determined for PVOH 10% Beads Percent of PVOH not cross-linked: PVOH x-linked film without clay: 0.6426J/g / 35.66J/g *100% = 1.8% PVOH x-linked film with 10% clay: 0.5314J/g / 35.66J/g *100% = 1.49% Notes Volumn of HCL used is not correct Higher concentration of clay requires higher stirring speed