Grzegorz Lapienis

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.

Preparation of monomethyl ethers of poly(ethylene glycol)s free of the poly(ethylene glycol)

In this report, poly(ethylene glycol) (PEG) was quantitatively removed from commercial monomethyl ethers of PEG (MPEG) by column chromatography on silica gel on a preparative scale. Most of commercial MPEG, with molecular weights as high as 5000, and containing only up to 20% of PEG, were effectively purified by this technique. The content of PEG in MPEG obtained is comparable or even lower than that in samples of MPEG prepared by anionic polymerization of ethylene oxide under strictly controlled conditions. An analytical approach combining H1 NMR and chromatography techniques indicates that the PEG content in the chromatographically purified MPEG samples is less than 1%.

The MPEG monophosphate ester: synthesis and characterization.

Methods of preparation of the phosphoric ester of monomethyl ether of poly(ethylene glycol) (MPEG-P) from MPEG (M n = 550 and 2000) and phosphoric acid (P), or its derivatives — pyrophosphoric acid (PY), polyphosphoric acid (PP) and POCl3– are described and compared. MPEG-P was isolated in a pure state (no detectable impurities) and characterized.

Poly(Alkylene Phosphate)S Related to Nucleic and Teichoic Acids

Abstract Preparation, some properties and applications of the bioanalogous poly(alkylene phosphatels, obtained according to the methods elaborated in these authors laboratory, are reviewed. Ring-opening polymerization, polyaddition, and two-step polycondensation methods are effective in the synthesis of polymers with various moieties of nucleic and teichoic acids (NA and TA respectively). The major aim of the work is to find relatively simple methods, allowing high molecular weight polymers to be prepared. Thus, preparation of poly(glycerol phosphate), poly(trimethylgne phosphate) bearing NA bases, and other related polymers with M n > 104 are described.

Synthesis and some properties of poly(alkylene phosphorothioate)s prepared from the corresponding poly(alkylene H-phosphonate)s

Several high molecular weight poly(alkylene phosphorothioate)s were synthesized by reacting poly(H-phosphonate)s with sulfur. The molecular weight of the resulting polymers are similar to the respective starting poly(alkylene H-phosphonate)s indicating that during sulfurization process no chain degradation occurred. The structure of poly(alkylene phosphorothioate)s was confirmed by the analysis of 1H, 13C and 31P NMR spectra.