User:Dominique Brager/Notebook/481 Notebook/2016/09/16

Biomaterials Design Lab

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Objective Make beads using the large batch profile. Use clay solution to have a 20% clay in film composite Run DSC on previously crosslinked films Prepare beads using 10% activated carbon instead of the clay. Description 20% clay beads: 1.25g PVA 1.25g PVA/4 = 0.3125g 0.3125g Bentonite * 97ml solution/3g bentonite = 10.1 mL bentonite solution 55mL solution - 10 mL bentonite solution - 15mL HCL: 30 mL H2O Create a solution of 1.25 g PVA, 10mL bentonite solution, and 15 mL conc HCl. Place this solution on a hot plate and heat/stir until everything has dissolved. Add 5 mL of this solution to a 50 mL solution of ethyl acetate stirring at 240 rpm in a dropwise manner. Add 0.5 mL of glutaraldehyde and stir at 260 rpm for 3 minutes. After 3 minutes, add 0.5 mL of glutaraldehyde and stir at 300 rpm for 2 minutes. After 7 minutes, add 7 mL of sodium bicarbonate and stir for 30 seconds. Activated Carbon Beads Same procedure as above using 2.5g PVA, 0.275 g Activated Carbon, 30mL 10% HCl. DSC run on: PVOH PVOH film with 10% bentonite from powder PVOH film with 10% bentonite from solution PVOH Beads with 10% clay solution Data 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 Both activated carbon and 20% beads formed well into many small beads. The cross linking of PVOH films was successful. Only a very small percentage of the films were not cross linked. Beads put in the oven for DSC came out black due to acid left over. This may have cross linked them even more. The DSC analysis does not show glass transition or melting point showing that the beads were successfully cross linked. Further analysis must be done on beads that were not dried in acid to be sure that beads are successfully cross linked.