User:Moira M. Esson/Notebook/CHEM-581/2012/10/01

Objectives

1. Crosslink glutaraldehyde film (PVOH MW 22K)
2. Test solubility:

• PVOH MW 22000+HCl+10%Maleic Acid

Glutaraldehyde Crosslinking

• The General Protocol described on 9/14/12 was followed
• Observations:
  • The sides of the glutaraldehyde film started to curl upwards ~20minutes into heating in the first fixant solution. When pushing down with a plastic pipette, the film was resubmerged in H₂O and uncurled
  • After 1hr in fixant solution, the film had a more rubber like texture
  • After 1/2 hour in 1% HCl solution, the film(which was a rubber like texture during this step in prior crosslinking)the film dissolved and resolidified on the stemless Buchner funnel. Part of the film was a gel-like substance, but the glutaraldehyde and fixant was discarded
• Note:
  • Previously crosslinked glutraldehyde film was weighed and stored in deionized H₂O

Mass of glutaraldehyde film before storage in H₂O: 0.6701g

Solubility

• The General protocol for testing viscosity was followed using viscometer 2190
• Observations:
  • Mass of film used: 0.0734g
  • The PVOH MW 22000+HCl+10%Maleic Acid film was allowed to stir for 1 hour. Although the film did not completely dissolve after 1 hour, the size of the film did shrink drastically
  • Stored the film that remained after 1hr. stirring for further testing

Viscosity Calculations

• Viscosity of pure H₂O at 25°C

• Average time = 241.29 s

• Viscosity of PVOH MW 22,000+[HCl]+10%maleic acid at 25°C

• Average time = 247.25 s