User:Moira M. Esson/Notebook/CHEM-581/2012/11/09

Objectives

1. Prepare solutions to run new PVOH based reactions

General Formula for reactions

Polyvinyl alcohol + [HAc]→Polyvinyl acetate

General Protocol for Polyvinyl acetate synthesis

1. For a 1:1 ratio of polyvinyl alcohol OH groups to polyvinyl acetate dissolve ~1g PVOH inH₂O
2. Add ~1.36g HAc. Add ~2 drops of HCl to reaction mixture to catalyze reaction.
3. Heat the reaction mixture to 40°C.
4. Allow the reaction to stir for 1 hour
5. Add sodium bicarbonate solution to the reaction mixture(titrate the reaction)
6. Rotavap the remaining reaction mixture

Calculations

• Overall, want to determine if have 1g of material how many moles of -OH groups. Once that is determined, will want to determine how many moles of -OH was reacted after the reaction.

Number of moles of OH groups in 1g PVOH: MW of repeating polyvinyl alcohol unit [C₂H₃OH]: 44.06g/mol

Polyvinyl alcohol repeating unit picture

 1gPVOH(1mol PVOH unit/44.06g) x (1mol OH/1mol PVOH unit)= 0.022696 mol OH/g 

Dye attachment calculations:

• Want to react .01% of the OH groups with the dye

MW 5-DTAF dye: 495.28g/mol

 (0.0227mol OH/g) x (.0001)= 2.27x10-6 moles dye

  2.27x10-6 moles dye x(495.28g dye/1mol dye)=0.001124g dye