I would like to know if its possible to prepare a cellulose thin film by solvent casting, preferably using water as the medium of dispersion. If yes, what is the minimum amount of cellulose weight% that can form a film?
Solvent casting is possible as long as you have a material which dissolves in certain solvent. Lower the BP of the solvent faster will be the drying time. Firstly it need to know the solubility of a given material in a specific solvent. That will give you the maximum loading. Ideally one would make 5 casts of a given material but using different concentration with equal spacing with maximum concetration being the solubility limit. After this you can tune and refine the process as per you requirement.
Ex: if solubility of A is 50 g/L then make 5 sample with 10 ml of solvent. Max solubility is 500 mg in 10 ml. Make 5 different concentration solution ( 100 mg, 200 mg ... 500 mg) in 10 ml. You cast and dry in oven ( normal or vacuum) or in open air or in desiccator as per your requirement,
Pure cellulose is not soluble in water alone. Cellulose is typically dissolved in sodium hydroxide and carbon disulfide or N-Methylmorpholine N-oxide. You can also dissolve cellulose in glacial acetic acid solution that results in the production of cellulose acetate (still not water soluble but soluble in methylene chloride). Try looking up the processes for making Cellophane, Rayon, or Lyocell.
Thanks for the informative answers, I was doing some lit. survey and found mentions of using DMF/DMac with Lithium chloride as the solvent, however I wasnt able to find details. If anyone has experience with that please share.