Scientific background for the structural and chemical modification of natural polymers (cyclodextrin, chitosan, cellulose) aiming at their functionalization was established and routes for modification of the synthetic polymers (most of all, urethane-containing) by polysaccharides for obtaining biodegradable polymer composites were determined as well. Novel cyclodextrin derivatives having isoindole fragments were synthesized and cyclodextrin was also modified by the derivatives of 5,11-dihydroisoindolo [2,1-а] quinazolinone-5. Chemically modified cyclodextrins (CDs) functionalized at the upper rim by the N-diethyldiacetate moieties, have been obtained and shown that they are perspective objects as sensitive layers for chemosensors. Using QCM (quartz crystal microbalance) method the study of sensitive films based on functionalized CDs towards to a volatile organic compounds (VOCs) of a different type has been provided and found out that their QCM responses to aromatic substances are much stronger compared with other organic vapors and are arranged into the following set: toluene > benzene > chlorobenzene > p-xylol. A range of aliphatic and aromatic polyurethanes based on cyclodextrin as hydroxyl-containing reagent for urethane bonding formation in their bulk was elaborated and their properties, structure and sorption capacity to the organic contaminants were studied. Applying cyclodextrin urethanemethacrylate synthesized, butyl methacrylate or acrylamide, co-polymers having cyclodextrin's fragments in the side chains were obtained by photopolymerization. Due to that fact, co-polymers possess the capability for sorption of a different organic species. Using Schiff's reaction, chemical attachment to chitosan of tetrazoloisoindole derivatives, a potential biology-active substances, was fulfilled and thus, a new chitosan derivatives were developed. Modification (mixing of the components followed by hot-mold pressing) of segmented polyurethane (4,4'-diphenylmethane diisocyanate, butylene glycol adipate Mw 2000 and 1,4-butanediol) and polyurethane cationomer (2,4-2,6-toluene diisocyanates isomers mixture, polypropylene glycol Mw 1000 and chain extender - N-aminoethyl piperazine) as well, by chitosan was fulfilled. It was established, that chitosan content (% wt.) influences onto structural stability for both systems, but compatibility much better in the case of polyurethane ionomer being used. Chitosan based composites are shown to demonstrate a good biodegradable characteristics alongside with properties intrinsic to a pure chitosan, to be influenced by pH environment (soils). The polymer composites based on segmented urethane-containing polymer and microcrystalline cellulose (up to 40%) and other derivatives (ethyloxyethyl cellulose, oxypropyl cellulose) as a fillers were prepared by the method of reaction molding. Using IR-spectroscopy, DSC, WAXS and SAXS the peculiarities of the composites' structure (microphase separation) and their behaviour in the buffer solutions in conditions imitating natural soil environment have been investigated. PU-polysaccharides composites exhibit increasing biodegradable characteristics in the model solutions with pH ranges from 4 to 8,5. The effective way is shown to get a functional polymers and related system, and forming of biodegradable polymer composites as well, governed by ecology expediency, is purposeful modification of natural polymers and their combination with synthetic ones.
