Malgorzata Basko

Dihydrophilic block copolymers with ionic and nonionic blocks. I. Poly(ethylene oxide)-b-polyglycidol with OP(O)(OH)2, COOH, or SO3H functions: Synthesis and influence for CaCO3 crystallization

Dihydrophilic block copolymers of poly(ethylene oxide)-b-polyglycidol were prepared and polyglycidol blocks converted into ionic blocks containing OP(O)(OH)2, COOH, or SO3H groups. Although phosphorylation of polyhydroxy compounds with POCl3 usually leads to insoluble products, phosphorylation of poly(ethylene oxide)-b-polyglycidol using a POCl3/OH ratio equal to 1/1 gave soluble products, predominantly monoester of phosphoric acid (after hydrolysis) (provided that the reaction was conducted in triethyl phosphate as solvent). All copolymers were characterized by 1H NMR, 13C NMR, and/or 31P NMR spectra for confirming their structure. The degree of substitution was determined from quantitative 13C NMR spectroscopy (inverted-gate decoupling-acquisition mode). Preliminary results indicate that from these three groups of block copolymers the phosphoric acid esters are the most effective ones at least in controlling the growth of CaCO3 crystals in aqueous solution.

Multifunctional membranes for solvent resistant nanofiltration and pervaporation applications based on segmented polymer networks.

Hydrophilic bis(acrylate)-terminated poly(ethylene oxide) was used as macromolecular cross-linker of different hydrophobic polyacrylates for the synthesis of amphiphilic segmented polymer networks (SPNs). Multifunctional composite membranes with thin SPN toplayers were prepared by in situ polymerization. As the support consisted of hydrolyzed polyacrylonitrile, the high chemical resistance of the composite membrane allowed applications of the SPN-based membranes in solvent-resistant nanofiltration (SRNF) and pervaporation (PV). The membranes show very high retention on Rose Bengal (RB) in different solvents, especially in strong swelling solvents such as tetrahydrofuran (THF) and dimethylformamide (DMF). The membranes were also tested in pervaporation for dehydration of ethanol and isopropanol (IPA). The selectivity of the membranes greatly depends on the composition or the ratio of the hydrophilic and hydrophobic phases of the SPN.

Aggregation of polylactide with carboxyl groups at one chain end in the presence of metal cations

Polylactides with one or more carboxyl groups at one chain end were synthesized by cationic polymerization according to activated monomer mechanism and by application of “thiol-yne” click chemistry for subsequent functionalization. End groups of such obtained polylactides were converted into ionic groups by neutralization of polymer solutions with metal oxides, mainly calcium oxide, and the aggregation of individual stereoisomers as well as that of the mixture of poly(l-lactide) (PLLA) and poly(d-lactide) (PDLA) was investigated. The extent and progress of the aggregation was followed by viscosity measurements, and aggregated polymers in the solid state were examined by SEM and DSC. Solution viscosity increase was observed upon the aggregation of individual PLA stereoisomers, whereas PLA stereocomplex precipitation occurred in the case of the aggregation of PLLA/PDLA/metal oxide mixture.

Studies of structures and concentration of active species in vinyl anionic polymerization by phosphorus end-capping

SummaryIt has been shown that chlorodiarylphosphines react quantitatively with carbanions giving the corresponding phosphines as the only products. On this basis, the method of determination of carbanions concentration by 31P-NMR has been developed. In the present paper the determination of n-C4H9Li concentration in the presence of other anions is described.