Vakuliuk P. Modified polymer membranes with desired functional properties

The dissertation is devoted to the development of the scientific basis of the preparation technology of modified polymeric membranes with pre-designed functional and improved selective and antibacterial properties using new technologically substantiated modifying compounds in forming solutions, as well as surface modification of polymeric membranes by the grafting of functional monomers, chemical surface transformations and immobilization of biocidal substances. The technological parameters of the formation of initial polysulfone, polyvinylidene fluoride and its copolymers, polyacrylonitrile membranes with the best functional characteristics for further modification, were substantiated. The results concerning to the technology of the preparation of polymer membranes with pre-designed functional properties by the bulk modification, as well as the results of the study of the structure and properties of the obtained membranes, were described. New ionogenic and complex compounds with oligomers of linear and branched structure with functional guanidinium, pyridinium, sulfate groups, oligoether-guanidine complexes with metal ions were synthesized for the bulk modification of initial PS, FVM and PAN membranes to improve their properties. The dissertation describes the results of investigations of the surface selective layers formation on the membranes due to the combination of the membranes’ surface pre-activation by chemical, physic-chemical and physical methods and subsequent surface modification by immobilization of oligomers and polymers with functional groups. Also, the effects of the aforementioned modification on the properties of the obtained polymeric membranes are shown. Methods of surface modifying of the initial polymeric membrane by functional monomers’ grafting, chemical surface transformations and immobilization of the functional and bactericidal compounds have been developed. The influence of modification’s type on the chemical structure of the received membranes, their functional and operational characteristics was studied. Methods of modifying the surface of polymeric PS membranes by linear and branched structure ionogenic oligomers with functional guanidinium, pyridinium, sulfate groups, which allow to regulate the value and the charge sign in a purposeful manner, have been developed. The proposed technological solutions will significantly increase the lifetime of the received membranes, compared with the traditional ones, which contributes to a significant economic effect from their use.