I don't have access to solvent casting technique, so I wanted to make those films w/o solvent casting device. I have tried to dissolved PVA in water and tried to dried it into a glass but It is very hard to separate the film and also it is not so thick as I wanted.
You can use DMSO as solvent and a PTE (Teflon) plate for casting. The obtained film is perfect. If you can use PVA with higher M.W., it´s better.
In my case, i use aluminium instead of glass and the film could be detached easily. The film thickness can be varied by changing the volume of the PVA solution. But please make sure that you use the same casting dish.
To prepare thin film of PVA you can use methyltrimethoxysilane pretreated glass plate, It will come out easily because of hydrophobic nature. PVA partially soluble in water. The solubility will increase if you heating at bout 60 - 70oC, You can make a thinfilm either spin coating or dip coating method of silane modified glass plate,
You can use DMSO as solvent and a PTE (Teflon) plate for casting. The obtained film is perfect. If you can use PVA with higher M.W., it´s better.
The biggest/most common mistake people make when solvent casting films is overlook surface interactions. You need a "mold release" if using glass because it is hydrophilic.
A quick and dirty method is to rub some petroleum jelly into the bottom of your glass dish with a kim-wipe. Rinse the finished film with hexanes to wash off any petroleum jelly residue.
Film thickness is going to be proportional to the amount of polymer you have in the dispersion, with some variability based on the quality of the polymer you are using. You're drivers are simply volume and concentration of your dispersion.
For many hydrophilic polymers such as polyvinyl alcohol it works quite well to cast them in normal petri dishes. You cant do high temperature drying of the film when it is in the petri dish, but it is possible to heat the film after it has been dried and removed from the petri dish.
Thank you all for your valuable suggestions. Your suggestions really are very very useful.
You can also fully dissolve PVA in distilled or deionized water by autoclaving for 30 minutes. The resulting solution will be clear and strongly viscous.
Thank you all for your suggestions. Your answers really are very useful.
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