As far as my information goes, HLB is defined just for emulsifiers & surfactants;
And since PVA, and PVP are polymeric stabilizer, HLB value seems to be meaningless !!! However, let me add that there are some polymer stabilizer which might have HLB... But, they are di-block ot tri-block copolymers such as PEO-PPO-PEO !!!
On the other hand, for example, PVA (partially hydrolyzed) is a random copolymer of Poly(vinyl acetate) and Poly(vinyl alcohol) !!!
Griffin's method (a method by which HLB is measured) assumes molecule as two completely separated portion : hydrophobic and hydrophilic, So, once again it seems that defining HLB for PVP or PVA is somewhat meaningless !!!
If I am not correct, please let me know. So many thanks.
Polyvinyl alcohol (PVA) is a nonionic surfactant and has a HLB value of 18.
[Qingguo Xu, Alison Crossley, Jan Czernuszka, Preparation and characterization of negatively charged poly (lactic-co-glycolic acid) microspheres, Journal of Pharmaceutical Sciences, 2008].
agree with Zahra partially. PVOH is nonionic (maybe a little bit negative charged), normally not called surfactant, colloid is more precisely. 18 maybe correct, should be more close to 20 since it's water soluble polymer. Although hydrolyzed randomly as Hossein said, some analysis found the there are VAC blocks intersected by VAL block like some surfactant.
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