Though atactic polymers of PVAc and PVA are more versatile than isotactic polymers, but is there any end applications of such polymers ?
Poly(vinyl acetate) – PVAC- has been known for a long time. When it is made from its monomer by free radical polymerization, it comes out as both atactic & amorphous. These structural properties determined the polymer's applications mainly as adhesive (including pastes and glues). As you know, poly (vinyl alcohol)-PVOH- is made by the hydrolysis of PVAC but the PVOH exhibits crystallinity although it is atactic (as its precursor).
It was possible to prepare syndiotactic PVAC which meant that a syndiotactic PVOH could be obtained from it but the hydrolysis was not as easy as before.
In PVAC, the pendant groups attached to the main polymeric chain "backbone" will be –O-CO-CH3 which combines 3 basic shapes (angular bent, planar trigonal, and tetrahedral ) which means a good degree of steric hindrance that causes difficulty (but NOT impossibility) in producing isotactic PVAC rendering the successive PVOH more difficult to make.
The stereo-irregular PVAC & PVOH are used for many applications. The syndiotactic analogues are still not used commercially & the isotactic analogues are in their infancy. I can anticipate the use of isotactic PVOH for medical purposes such as hydrogels or cryogels possibly offering "novel" desirable rates of diffusion or drug release.
Dear Sethi, I have been working with PVA-OH for the purpose of medical. We can electrospin the polymer or phase inversion method to make into membrane and use for healing treatment as bandage. Hope this helps you.
These are biomedical materials and have application in medical and pharmacy field. PVOH use in current pharmaceutical products as an excipient. Polyvinyl alcohol is one of the most important commercially used polymer with uses as adhesive and thickener material in paints and shampoos, as a textile sizing agent, as carbon dioxide barrier in PET bottles etc.
In short,
PVOH, nowadays used a lot in biomedical applications like drug delivery. Used as adhesive in combinations with films like chitosan for trans-dermal patches.
PVAc, plays a pertinent role in adhesive industry. Used in paint, and sealant industry as well. Has high film forming properties (coalescence very easy). Used in almost all the adhesives to enhance the adhesive component of the system which itself consists two things : 1) Adhesion energy and 2) Bulk dissipation component. Also, decreases the MFFT of components with high cohesion.
Thanks
I hope this helps you.
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