Hello, I need to understand why polymer such as polyacrylonitrile (which is water insoluble) doesn't dissolve in water after amination with any amine. Amino groups is hydrophilic and should increase hydrophilicity of PAN but it didnt!
Dear Samar Khattab, PAN is known by its high intra- and inter-molecular interactions caused by the high dipole-dipole moment of CN (strong internal cohesion limits the free volume for solvents diffusion, in addition to crystallinity), and this is behind most if not all properties of PAN. Amination doesn't bring the required solubility for the same reason. If you the aqueous solubility then use NaSCN. Please have a look at the following chapter. My Regards
https://link.springer.com/chapter/10.1007/3-540-09442-3_6
Hello Samar, which method did you use for the conversion of nitrile to amine? Extent of functionality can affect the solubility.
Also, you can try lowering the pH with HCl to increase solubility if your experiment is pH independent.
@Partha PAN was reacted with ethylene diamine (10 molar excess) in DMF , 24H , 80_90 degree.
I will try to do Protonation of amino groups, either at low ph or by using quaternization agent.
Dear Samar Khattab, just be aware that PAN hydrolysis is possible at both acid and alkaline pH's.
https://doi.org/10.1021/ma010213o
https://doi.org/10.1002/1521-3935(20001101)201:163.0.CO;2-5
- Badges
- Science method