March 28, 2024, 08:25:46 PM
Forum Rules: Read This Before Posting


Topic: dissolution of polyvinyl alcohol  (Read 1289 times)

0 Members and 1 Guest are viewing this topic.

Offline infectus

  • New Member
  • **
  • Posts: 3
  • Mole Snacks: +0/-0
dissolution of polyvinyl alcohol
« on: May 13, 2019, 10:00:29 AM »
Hi,

I'm a french trainee who work for a PVC industry.
I work on the validation techniques for the good dissolution of polyvinyl alcohol.
Anyone know a technique for showing that polyvinyl alcohol are well dissolved in water.

Sorry for my english and thanks if you can help me  ;)

Offline wildfyr

  • Global Moderator
  • Sr. Member
  • ***
  • Posts: 1771
  • Mole Snacks: +203/-10
Re: dissolution of polyvinyl alcohol
« Reply #1 on: May 13, 2019, 12:14:15 PM »
Mix a given amount of it in 90C water, then let it cool and filter. Remove whatever gets caught in filter and dry it. This will give a measurement of solubility of a given PVA in water.

Offline hollytara

  • Chemist
  • Full Member
  • *
  • Posts: 317
  • Mole Snacks: +39/-0
Re: dissolution of polyvinyl alcohol
« Reply #2 on: May 14, 2019, 12:04:50 AM »
PVA is usually pretty soluble - but it does depend on MW and the percent of hydrolysis from polyvinyl acetate.  It can be a little odd also - sometimes it is more soluble in cold water.  But using a standard quantity and a standard volume of water at a standard temperature allows you to compare.  After filtering, I always prefer to measure what IS in the water - take a standard volume (100-1000 microliters) and put it in a small tared beaker, then evaporate to dryness, then weigh to see how much PVA is in the solution. 

Offline infectus

  • New Member
  • **
  • Posts: 3
  • Mole Snacks: +0/-0
Re: dissolution of polyvinyl alcohol
« Reply #3 on: May 14, 2019, 05:47:38 AM »
thanks for your reply .
I have try to dissolve the PVA at 90°C during 30min but it did not work . I have let the agitation during the night and its dissolve.

For know if all is well disolved i have pass the sample on the dessiccator but i thinks it's not the good maner.
I heard about a method with iodine. Have you heard of it before?

Sponsored Links