Kolio Troev

• D Sc
• Professor (Full) at Institute of Polymers

Among polymer wastes, poly(ethylene terephthalate) (PET) is the most important commercial thermoplastic polyester. Less than 30% of total PET production is recycled into new products. Therefore, large amounts of waste PET need to be recycled. We describe a feasible approach for the direct application of the glycolysis products of PET (GP-PET), with...

pH-sensitive amphiphilic diblock polyphosphoesters containing lactic acid units were synthesized by multistep one-pot polycondensation reactions. They comprise acid-labile P(O)-O-C and C(O)-O-C bonds, the cleavage of which depends on the pH of the medium. The structure of these copolymers was characterized by 1H, 13C {H}, 31P NMR, and size exclusio...

In this study, we analyzed the properties of amphiphilic alkyldi(methoxy poly(ethylene glycol) (MePEG)350-lactate) phosphates based on ethyl lactate, the monomethyl ether of poly(ethylene glycol)350, and alkyldichloro phosphates. Interestingly, these triesters combine two biodegradable bonds, –P(O)-O-C and –C(O)-O-C-, and include hydrophilic (MePEG...

Multistep one-pot polycondensation reactions synthesized amphiphilic diblock polyphosphoesters containing lactic acid units in the polymer backbone. At the first step was synthesized poly[poly(ethylene glycol) H-phosphonate-b-poly(ethylene glycol)lactate H-phosphonate] was converted through one pot oxidation into poly[alkylpoly(ethylene glycol) pho...

Using a novel strategy, amphiphilic polyphosphoesters based on poly(oxyethylene H-phosphonate)s (POEHP) with different poly(ethylene glycol) segment lengths and aliphatic alcohols with various alkyl chain lengths were synthesized using polycondensation reactions. They were characterized by 1H NMR, 13C {H} NMR 31P NMR, IR, and size exclusion chromat...

Background/aim: Serious side effects are associated with the use of doxorubicin. Nanoparticles as carriers for anticancer drugs are useful for reducing side effects and improving therapeutic effects. In this study, a polymer for preparing doxorubicin-containing nanoparticles was developed. Using a novel strategy, a biodegradable poly(oxyethylene g...

In this paper we have demonstrated a new synthetic approach to a phosphorus and silicon containing inorganic polymer with a chain structure [‐O‐P(O)(H)‐O‐Si(CH3)2‐]. It has been obtained from dichlorodimethylsilane and dimethyl ester of H‐phosphonic acid taken in excess via a catalyst and solvent free process, performed in two stages. The first one...

A new method for the preparation of poly(oxyethylene phosphoramidate)s and glycopolymers is developed via modification of poly(oxyethylene H-phosphonate) which is a biodegradable, biocompatible and low toxic polymer. The phosphonate groups of the precursor are converted into tri-coordinated phosphorus species yielding poly(oxyethylene trimethylsily...

We demonstrated a feasible approach for the preparation of a biodegradable, water soluble polyphosphoester based paclitaxel complex. Applying poly(hydroxyoxyethylene phosphate) which contains both a strong proton accepting PO group and a proton donating POH group, paclitaxel has been physically immobilized onto the polymer via H-bonding. The water...

The structure of an α-aminophosphonic acid diester, p-[N-methyl(diethoxyphosphonyl)-(4-dimethylaminophenyl)]toluidine, was determined by single-crystal X-ray diffraction. The compound is a racemic mixture and crystallizes as colourless prisms in a centrosymmetric manner in the monoclinic crystal system, space group P21/c, with two molecules in the...

Well-defined poly(alkylene trimethylsilylphosphite)s (P+3) were obtained for the first time via silylation of poly(oxyethylene H-phosphonate)s (P+5) with N,O-bis(trimethylsilyl)acetamide or trimethylsilyl chloride. The reaction with both silylating agents proceeds at room temperature in quantitative conversion. It has been followed by 1H and 31P NM...

A new mechanism of the Atherton-Todd reaction is discussed. The first step of the reaction between diesters of H-phosphonic acid and carbon tetrachloride in the presence of a base, commonly triethylamine, is a salt formation between carbon tetrachloride and the base [amine.Cl]+CCl3-. The trichloromethanide anion [CCl3-] deprotonates dialkyl H-phosp...

Polymer complex constructed from WR 2721 and poly(hydroxyoxyethylene phosphate) was synthesized. The structure of complex formed was elucidated by (1)H-, (13)C, (31)P NMR and FT-IR spectroscopy. The radioprotector was immobilized via ionic bonds. Radioprotective efficacy was evaluated by clonal survival of stem cells in crypts of mouse small intest...

Polymers bearing reactive groups are attractive materials for bio-medical applications. Five-membered cyclic carbonates (1,3-dioxolan-2-one derivatives) display high chemo-selective reactivity towards aliphatic amines. The reaction proceeds under mild physiological conditions. Polymers bearing 1,3-dioxolan-2-one moieties present promising candidate...

Poly(oxyethylene aminophosphonate)s synthesized on the basis of biodegradable poly(phosphorester)s and Schiff bases were tested in vitro for antitumor activity against a panel of six human epithelial cancer cell lines, for cytotoxicity to mouse fibroblast cells and in vivo for clastogenicity and antiproliferative effects. The polymers showed lower...

The Schiff bases N-furfurylidene-p-toluidine and N-(4-dimethylaminobenzilidene)- p-toluidine, and the recently synthesized aminophosphonic acid diesters p-[N-methyl- (diethoxyphosphonyl)-(2-furyl)]toluidine and p-[N-methyl(diethoxyphosphonyl)-(4-dimethylaminophenyl)] toluidine were tested for in vitro antitumour activity on six human epithelial can...

Aminophosphonates, as structural analogues of natural α- aminocarboxylic acids, constitute a valuable class of compounds with a wide spectrum of biological activity, including treatment of metabolic disorders and cancer. A recently synthesized furan-bearing aminophosphonate, namely N,N-dimethyl-[N'-methyl(diethoxyphosphonyl)-(2-furyl)]-1,3-diaminop...

Macromolecular conjugates of a dinuclear platinum complex with a spermidine bridge were synthesized using poly(oxyethylene H-phosphonate)s as precursor polymer. The complex species were attached to the polymer chain via a phosphoramide bond resulting from the reaction between the H-phosphonate groups and the middle amino group of the spermidine moi...

The X-ray crystal structures of the anthracene-derived bis-aminophosphonates 4.4′-bis[N-methyl(diethoxyphosphonyl)-1-(9-anthryl)]diaminodiphenylmethane (1) and 1,3-bis[N-methyl(diethoxyphosphonyl)-1-(9-anthryl)]diaminobenzene (3) are reported. The X-ray analyses demonstrated that both compounds crystallize in a centrosymmetric manner containing a m...

The low molecular weight of many chemotherapeutics causes their untargeted distribution in the body and fast renal clearance, which leads to a loss of therapeutic activity and to unspecific toxic side effects. Therefore, there is a growing interest in conjugating anticancer drugs to water soluble polymers and thus, take advantage of the 'enhanced p...

A review of the research efforts on the development of pathways for the degradation of polymer–wastes of polyurethanes, polycarbonates and polyamides by esters of H-phosphonic and phosphoric acids is presented. Our group has made it clear, thanks to a vast research program devoted to this subject, that alkyl esters of H-phosphonic and phosphoric ac...

Kril, A., Georgieva, A., Iliev, I., Tsacheva, I., Vodenicharova, E., Tasheva, E., Tosheva, T., Kraicheva, I., Troev, K.

Poly(alkylene H-phosphonate)s are a relatively new family of biodegradable, biocompatible, low toxic (1000 mg/kg) polymers that are being actively investigated for pharmaceutical and biomedical applications such as drug delivery and tissue engineering. A number of synthetic routes have been explored for the synthesis of these polymers, including ri...

The Schiff bases N-furfurylidene-p-toluidine and N-(4-dimethylaminobenzilidene)-p-toluidine, and the recently synthesized aminophosphonic acid diesters p-[N-methyl-(diethoxyphosphonyl)-(2-furyl)]toluidine and p-[N-methyl(diethoxyphosphonyl)-(4-dimethylaminophenyl)]toluidine were tested for in vitro antitumour activity on six human epithelial cancer...

A novel method of oxidation of poly(alkylene H-phosphonate)s is presented here. Trichloroisocyanuric acid is used for the first time as a chlorination agent of poly(alkylene H-phosphonate)s. Poly(oxyethylene chlorophosphate) was obtained in quantitative yield at room temperature in 1 h from poly(oxyethylene H-phosphonate) and trichloroisocyanuric a...

The synthesis of two novel bis-aminophosphonates bearing anthracene rings – bis[N- methyl(diethoxyphosphonyl)-1-(9-anthryl)]benzidine (3) and 4,4′-bis[N-methyl(diethoxy-phosphonyl)-1-(9-anthryl)]diaminodiphenylmethane (4) – via the Kabachnik–Fields reaction is reported. The compounds have been characterized by elemental analysis, TLC, IR, NMR (H, C...

The syntheses of platinum(II) complexes of bis(dimethylphosphinylmethylene)amine and bis(aminomethyl)phosphinic acid were investigated. In the case of bis(dimethyl-phosphinylmethylene)amine the reaction with K2[PtCl4] yields the potassium amino-trichloroplatinate K[PtCl3L] (L = bis(dimethylphosphinylmethylene)amine), which was characterized by mult...

The molecular and crystal structures of two α-aminophosphonic acids with small substituents at the α-carbon atom—(1-aminoethyl)phosphonic acid 1 and (1-amino-2,2-dimethylpropyl)phosphonic acid monohydrate 4—were determined by single-crystal X-ray diffraction studies. The crystal structures provide important information on the hydrogen bonding prope...

We investigated the mechanism of the reaction of paraformaldehyde with phosphorus trichloride in the presence of carboxylic acids (acetic, propanoic, and formic). Our results revealed that bisphosphonic acids were obtained without the use of water. The structures of the reaction products were studied by 1D and 2D homonuclear and heteronuclear 1H-,...

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A new Schiff base, 9-anthrylidene-furfurylamine and three novel anthracene-containing α-aminophosphonates, [N-methyl(dimethoxyphosphonyl)-1-(9-anthryl)]-p-toluidine, [N-methyl(diethoxyphosphonyl)-1-(9-anthryl)]-p-toluidine and [N-methyl(diethoxyphosphonyl)-1-(9-anthryl)]furfurylamine were synthesized. The compounds have been characterized by elemen...

The title compound, C26H28NO3P, crystallized with two independent mol­ecules in the asymmetric unit. The structural features (bond lengths and angles) of the two mol­ecules are almost identical. The inter­planar angle between the anthracene and toluidine rings is similar in the two mol­ecules, with values of 82.92 (5) and 80.70 (5)°. In the crystal...

The title compound, C24H24NO3P, crystallizes as a racemate with two mol­ecules in the asymmetric unit. The structural features (bond lengths and angles) of the two mol­ecules are almost identical. The dihedral angle between the anthracene and toluidine rings is similar in the two mol­ecules, with values of 48.36 (9) and 51.15 (9)°. The methyl group...

First examples of ene diamines with a phosphonate function at the C=C double bond were obtained by the reaction of dialkyl H-phosphonates with bis(N-tert-butyl)-diimine derived from glyoxal, [1,4-bis(tert-butyl)-1,4-diaza-1,3-butadiene], and isolated as hydrochlorides. Preferentially the cis-diamine is formed. The new phosphonates are characterized...

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

A new 5′-O-AZT prodrug was synthesized by conjugating 3′-azido-2′,3′-dideoxythymidine (AZT) with poly(oxyethylene H-phosphonate) at room temperature under Atherton-Todd reaction conditions. The acute toxicity of poly(5′-O-AZT-oxyethylene phosphate) was reduced significantly in comparison with non-immobilized AZT.

The synthesis of four novel poly(oxyethylene aminophosphonate)s through an addition of poly(oxyethylene H-phosphonate)s to N-(4-dimethylaminobenzylidene)-p-toluidine or N-furfurylidene-p-toluidine is reported. The IR and 1H, 13C and 31P NMR data of the poly(aminophosphonate)s are given. The polymers consist of aminophosphonate and poly(ethylene gly...

Phosphorus- and silicon-containing monomers are synthesized by the reaction of dealkylation of methyl esters of the phosphonic and phosphoric acids with dimethyl (and diphenyl) dichlorosilane. It is shown that the phosphorus- and silicon-containing monomers are condensed to oligomers with the evolution of the corresponding methyl esters of the phos...

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Flexible polyurethane foams (PU) based on toluene diisocyanate and polyether polyol have been degraded by dimethyl H-phosphonate (DMP) in the presence of catalysts such as potassium tert-butoxide, potassium and azobisisobutyronitrile (AIBN). The structure and molecular weight of the degraded products were monitored by P-NMR and GPC. The degradation...

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

A series of new cycloalkanespiro-5-hydantoin phosphonic acids have been synthesized and characterized. The mixture of [(2,4-dioxo-1,3-diazaspiro-alkane-3-yl)-methyl]phosphonic acids and [(2,4-dioxo-1,3-diazaspiro-alkane-1,3-diyl)dimethyl]diphospho-nic acids was obtained from cycloalkanespiro-5-hydantoins, formaldehyde, and phosphorus trichloride in...

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

In this article, a new synthetic approach to a 1,4,2-oxazaphosphorinane, and to α-ethyl-α-N-(hydroxyethylamino)methyl phosphonicacid and their sodium salts is described. The title compounds were characterized by NMR and FAB spectroscopy. © 1999 John Wiley & Sons, Inc. Heteroatom Chem 10:627–631, 1999

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

The synthesis of three novel alpha-aminophosphonic acid diesters N,N-dimethyl-[N'-methyl(diethoxyphosphonyl)-(2-furyl)]-1,3-diaminopropane, p-[N-methyl(diethoxyphosphonyl)-(2-furyl)]toluidine and p-[N-methyl(diethoxyphosphonyl)-(4-dimethylaminophenyl)]toluidine through an addition of diethyl phosphite to N,N-dimethyl-N'-furfurylidene-1,3-diaminopro...

Aminophosphonic acids are an important group of medicinal compounds, and their synthesis has been a focus of considerable attention in synthetic organic chemistry as well as medicinal chemistry. Although the phosphonic and carboxylic acid groups differ considerably with respect to shape, size, and acidity, alpha-aminophosphonic acids are considered...

The new α-aminophosphonic acids are synthesized, reacting (9H-fluoren-9-yl)urea with formaldehyde and phosphorus trichloride. (9H-Fluoren-9-yl)urea was prepared from spiro(fluoren-9,4′-imidazolidine)-2′,5′-dione by alkaline hydrolysis with Ba(OH)2. The structure of the title compounds was proved by means of IR, 1H, 13C, and 31P NMR spectroscopy. ©...

Novel water soluble polymer complexes of bendamustine hydrochloride, a bifunctional alkylating agent with antimetabolic and cytotoxic activity, were developed using biodegradable polymer carriers-poly(oxyethylene H-phosphonate), poly(methyloxyethylene phosphate) and poly(hydroxyoxyethylene phosphate). Bendamustine hydrochloride was immobilized onto...

A series of Calpha,alpha-disubstituted cyclic derivatives of N-(phosphonomethyl) glycine have been synthesized and characterized. They exhibited moderate clastogenicity, low antiproliferative activity on mice bone marrow cells and well expressed cytotoxicity against human tumor cell lines. The 8- and 12-membered cyclic analogs proved superior to th...

New functional polyphosphoesters bearing 1,3-dioxolan-2-one and P–H or P–OCH3 groups, or urethane and hydroxyl groups have been synthesized and characterized. Poly(oxyethylene H-phosphonate) was used as precursor polymer. It was reacted with 4-ethenyl-1,3-dioxolan-2-one through the addition of the polymer P–H groups to the double CC bond of the cyc...

It was found that the reaction of dimethyl H-phosphonate (1) with 2-hydroxyalkyl-N-2′-hydroxyalkyl carbamates at 135°C includes several chemical reaction steps: (i) chemical transformations of 1-methyl-2-hydroxyethyl-N-2′-hydroxyethyl carbamate (2) and 2-methyl-2-hydroxyethyl-N-2′-hydroxyethyl carbamate (3); (ii) transesterification of dimethyl H-p...

Novel poly(oxyethylene aminophosphonate)s were obtained for the first time with high yield via an addition polymer analogous reaction between poly(oxyethylene H-phosphonate)s and N,N-dimethyl-N>-furfurylidene-l,3-diami- nopropane (Schiff base). It was shown that Cdl2 accelerates the addition of the P-H group of the poly(oxyethylene H-phosphonate)s...

α-Ethyl-N-(phosphonomethyl) glycine is synthesized and characterized by NMR and FAB spectroscopy. The cytotoxicity, clastogenic and antiproliferative effect of 3-ethyl-2-hydroxyl-2-oxo-1,4,2-oxazaphosphorinane, sodium salt of 3-ethyl-2-hydroxyl-2-oxo-1,4,2-oxazaphosphorinane, α-ethyl-α-N-(hydroxyethylamino) methylphosphonic acid, α-ethyl-N-(phospho...

Results on synthesis of poly(3-hydroxybutyrate)s possessing one or two hydroxyl groups at one terminus of the chain and carboxylic group at the other chain end are reported. These polymers were further functionalised via transesterification with dimethyl H-phosphonate thus incorporating a reactive/biodegradable center in the polyester backbone. Blo...

This article describes a new approach for the recycling of microporous polyurethane elastomers by Tris(1-methyl-2-chloroethyl) phosphate-induced degradation. The phosphorus-containing degradation products formed are transformed into reactive intermediates by reaction with propylene oxide and are used for the preparation of rigid polyurethane foams....

This study describes the synthesis and characterization of polymer complexes constructed from the radioprotective agent S-2(3-aminopropylamino) ethylphosphorothioic acid dihydrate (amifostine or WR-2721), applied in the radiation cancer treatment, and biodegradable poly(oxyethylene H-phosphonate), poly(hydroxyoxyethylene phosphate), or poly(methylo...

The cytotoxic effects of the novel compounds were tested against a panel of human tumor cell lines. All of the compounds under investigation exhibited concentration-dependent cytotoxic effects against the leukemic cells, following 72 h exposure, which allowed the construction of the corresponding concentration-response curves and the determination...

The chapter summarizes some of the most important practical applications of H-phosphonates and their derivatives in the areas of agriculture, industry, and medicine, as well as some new promising developments with application potential. The versatility of these compounds allows for their use as phosphorylation agents for a variety of substrates. Or...

The chapter discusses the diesters of H-phosphonic acid that occupy a major position in organophosphorus chemistry as they are intermediates in the synthesis of a variety of bioactive products, including aminophosphosphonates, aminophosphonic acids, and others. The strong polar character of the phosphoryl group of H-phosphonates is responsible to a...

The chapter focuses on the important classes of biologically active compounds, such as aminophosphonates, aminophosphonic acids, bisphosphonates, nucleoside H- phosphonates, and 1,2 and 2,3 epoxyalkylphosphonates. The chapter also discusses the methods for synthesis of these compounds, reactivity of these phosphonates, and their synthetic applicati...

The title compound, C6H12NO5P, was synthesized as an inter­mediate phase in a search for new N-(phosphono­methyl)glycine derivatives. The mol­ecules are held together by O—H⋯O hydrogen bonds, forming chains along the b axis in the crystal structure. The observed mol­ecular structure is compared with that calculated by the density functional theory...

2,4,6-triamino-1,3,5-triazinealkylammonium alkyl-phosphonates-{C3H6N6R}+−OP(O)(X) (OR) (X=H, CH3; R=CH3; C2H5) and 2,4,6-triamino-1,3,5-triazineammonium dimethyl phosphate were synthesized (X=OCH3; R=CH3). When R=CH3 these salts decompose evolving carbene “CH2” and convert into the corresponding ammonium salts {C3H7N6}+-OP(O)(X)(OR). It has been es...

Novel alpha-aminophosphonic acids are synthesized reacting 1,3-oxazolidin-2-one derivatives with formaldehyde and phosphorus trichloride. Treatment of N-(phosphonomethyl)oxazolidinones with aqueous NaOH gave the expected alpha-aminophosphonic acids. The oxidation of (2-hydroxy-1,1-dimethylethylamino)methyl phosphonic acid in the presence of CdO and...

"This book introduces and reviews the chemistry, characteristics and application of diesters of H-phosphonic acid and is an excellent source of ideas to those already working or who plan to work in the field of phosphorus-containing compounds."--BOOK JACKET.

This paper describes a novel strategy for the recycling of polyamide materials and their transformation into functional reactive oligomers with new properties. The method is illustrated by the heating of polyamide-6 (20,000 Da) in the presence of diesters of the phosphonic acid, (RO) 2 P(O)H, where R could be eCH 3 , eC 2 H 5 or eC 6 H 5 . It is fo...

Poly(alkylene hydrogen phosphonate)s with a number‐average molecular weight of about 3 000 Da were obtained by a transesterification of dimethyl hydrogen phosphonate with poly(ethylene glycol) (PEG 400) under microwave irradiation with a very short reaction time (55 min) relative to that of classical thermal heating (9 h). The structure of the resu...

The molecule of the title compound, C5H14NO4P, exists as a zwitterion rather than as [1-(hydroxyethyl­amino)propyl]­phospho­nic acid, with the N atom of the amino group protonated and the phospho­nic acid group negatively charged. In the crystal structure, the molecules are linked via extensive hydrogen bonding, forming layers parallel to (100).

Poly(ethylene terephthalate) waste materials were depolymerized by ethylene glycol (EG), diethylene glycol (DEG), and propylene glycol (PG) in the presence of a novel catalytic system: titanium (IV)-phosphate. The new catalyst was synthesized through a reaction of TiCl4 with triethyl phosphate (C2H5O)3P(O). It was found that the depolymerization of...

The original article to which this Erratum refers was published in Journal of Applied Polymer Science, 90, (4) 2003, 1148–1152. No abstract.

For Abstract see ChemInform Abstract in Full Text.

The paper reports on the possibility of direct use of some products of poly(ethylene terephthalate) glycolysis, bis(2-hydroxyethyl) terephthalate and ethylene glycol mainly, in the process of glass-fibre-reinforced plastics manufacturing. The addition of toluene diisocyanate as an intermediating agent was an important prerequisite for their incorpo...

4-Hydroxymethyl-1,3-dioxolan-2-one has been prepared in 70% yield from 1-chloro-2,3-epoxypropane with alkali metal hydrogen carbonates under phase transfer catalysis conditions. Onium halides exhibit higher catalytic activity compared with that of tertiary amines or 18-crown-6.

Poly(alkylene phosphate)s of low molecular weight were synthesized by polytransesterification of dialkyl phosphonates with poly(ethylene glycol)s (PEG). These poly(alkylene phosphonate)s were then converted into poly(alkylene phosphate)s by using the Atherton-Todd reaction in methanol as a solvent. The compound 2-phenylethylamine was immobilized on...

The feasibility of the reaction of poly(oxyethylene phosphonate) 1 with chloroacetone under phase-transfer catalysis conditions for the preparation of poly(oxyethylene phosphonate)s bearing α-hydroxyl and oxirane groups in the side chains has been investigated. It has been established that the first stage of the reaction involves addition of the P–...

The synthesis of 4-substituted 1,3-dioxolan-2-ones from the interaction between carbon dioxide and oxiranes in the presence of a catalytic system composed of tetraalkylammonium or phosphonium halide and calcium chloride has been investigated. It has been established that calcium chloride enhances the catalytic activity of the onium halides used. A...

The necessity to apply near-toxic amounts of radioprotective drugs to achieve adequate protection during radiation treatments represents a major problem in human medicine. One of the promising strategies to suppress the toxicity of these drugs involves their incorporation into biocompatible polymers. In this study cysteamine (Cy) was attached to po...

The interaction of poly[2,2-bis(4-hydroxyphenyl)propanecarbonate] (PC) with phosphonic acid dialkyl esters [(RO)(2)P(O)H, where R=CH3 or CH3CH2] or with phosphoric acid triethyl ester (CH3CH2O)(3)P(O) was studied. Treatment of PC pellets with phosphonic acid dialkyl esters at 160 degrees C or with triethyl phosphate at 180 degrees C yielded phospho...

Microporous polyurethane elastomer, based on diphenylmethane diisocyanate (MDI) and polyester polyol-Bayflex 2003E has been converted into a liquid by treatment with diethyl phosphonate and tris(1-methyl-2-chloroethyl) phosphate. The structure of the degraded products has been studied by 1H, 13C and 31P NMR spectroscopy. The degraded products are p...

Flexible polyurethane foam based on toluene diisocyanate and polyester polyol has been liquefied by treatment with either dimethyl phosphonate (CH3O)2P(O)H or diethyl phosphonate (C2H5O)2P(O)H at 160°C. The product degraded has been studies by 1H, 13C, and 31P nuclear magnetic resonance (NMR) spectroscopy. The likely reaction mechanism is presented...

In this article, a new reactivity of dimethyl hydrogen phosphonate is described. It was established that the reaction between dimethyl hydrogen phosphonate and urethane encompasses two simultaneous processes: an exchange reaction between the methoxy groups of the phosphonate and urethane groups and alkylation of the urethane. The reaction of dimeth...

It was established that flexible polyurethane foams based on polyester or polyether polyol and toluene diisocyanate can be converted quantitatively into liquid form by treatment with triethyl phosphate (C2H5O)3P(O). Structures of the degraded products were studied by 1H, 13C and 31P NMR spectroscopy. The degraded products are phosphorus containing...

Microporous polyurethane elastomer, based on 4,4′-diphenylmethane diisocyanate and polyester polyol Bayflex 2003 (Bayer AG), was degraded by phosphoric acid esters (CH3CH2O)3P(O) and (ClCH2CH2O)3P(O) at 180°C. Structure of degraded products was investigated by means of 1H-, 13C-, and 31P-NMR spectroscopy. © 2000 John Wiley & Sons, Inc. J Appl Polym...

The new method for chemical degradation of polyurethanes by treating them with esters of phosphonic and phosphoric acids is presented. The chemical degradation of flexible polyurethane foam based on toluene diisocyanate and polyether polyol with dimethyl phosphonate is reported. The primary aim of these studies is to develop a new method for conver...