I am trying to study the swelling behavior of modified PVA films in different alcohol and organic solvent
Usually with increasing C content the swelling behavior increases. However it also depends highly on the nature of organic molecule.
I'm not sure what you mean exactly...Is it the swelling degree of PVA as a function of its hydrolysis degree (% -OH)? As there are more -OH groups, the polymer is more crystalline, therefore it has a lower swelling degree...
http://www.academicjournals.org/article/article1404813310_Marin%20et%20al.pdf
As you know, PVA cannot be obtained by the polymerization of its monomer since vinyl alcohol simply does not exist.
Instead, PVA is made by the hydrolysis of poly(vinyl acetate) "PVAc". This is a conversion of amorphous atactic polymer into another polymer with smaller pendant –OH groups than what they were before (as the more bulky –O-CO-CH3 acetate groups). PVA has a higher degree of crystallinity than PVAc. However, we cannot expect 100% conversion and PVA is not completely crystalline.
There are uses in which PVA is required to swell. In big hospitals, beds & pillows sheets are collected in PVA thin wide bags and the bags are thrown inside big washing machines. What happens is that PVA swells first in warm water & then dissolves allowing the cleansing of the sheets.
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