Alkylene Oxide Research Articles

Synthesis and characterization of polysulfone-poly(alkylene oxide) block copolymers containing poly(dimethylsiloxane)

Block copolymers of polysulfone–poly(alkylene oxide)–poly(dimethylsiloxane) have been prepared by the addition of preformed α,ω-bis(hydrogensilyl)poly(dimethylsiloxane) oligomers to allyl end-capped poly(alkylene oxide)–polysulfone. The hydrosilylation reaction, catalyzed by platinum, was employed for incorporation of the siloxane chain into the copolymers in a 1 : 1 or 1 : 2 molar ratio of Si–H-terminated polydimethylsiloxane to allyl end-capped polysulfone. The products were characterized by IR, 1H-NMR, and gel permeation chromatography. The thermal stability was determined by thermogravimetric analysis. Differential scanning calorimetry was used to investigate microphase separation in the block copolymers. © 1996 John Wiley & Sons, Inc.

Synthesis and characterization of polysulfone‐poly(alkylene oxide) block copolymers containing poly(dimethylsiloxane)

Synthesis and characterization of polysulfone‐poly(alkylene oxide) block copolymers containing poly(dimethylsiloxane)

5532389 Process for preparing alkylene oxides: Trent David L; Quarderer George J; Bargeron Kim; Greminger Douglas C; Koranek David; Stewart Erik; Swisher Curtis N; Tirtowidjojo Cheryl A; Tirtowidjojo Dani, Lake Jackson, TX, United States assigned to The Dow Chemical Company

5532389 Process for preparing alkylene oxides: Trent David L; Quarderer George J; Bargeron Kim; Greminger Douglas C; Koranek David; Stewart Erik; Swisher Curtis N; Tirtowidjojo Cheryl A; Tirtowidjojo Dani, Lake Jackson, TX, United States assigned to The Dow Chemical Company

ChemInform Abstract: Hydroperoxides as Pseudohalides: Oxidation, Oxidative Alkylation, Acylation and Arylation of Acrylonitrile.

AbstractChemInform 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.

The synthesis and study of the photoinitiated cationic polymerization of novel cycloaliphatic epoxides

AbstractThe synthesis of a series of difunctional epoxides bearing two epoxycyclohexyl groups linked together by an alkylene ether group has been carried out. Subsequently, the reactivities of these novel monomers was investigated and compared to the reactivity of the cycloali‐phatic epoxide, 3,4‐epoxycyclohexylmethyl 3′,4′‐epoxycyclohexane carboxylate (I) in pho‐toinitiated cationic polymerization. It was observed that alkylene oxide linking the two epoxycyclohexyl groups was short and the monomers are more reactive than I. The effects of the photoinitiator structure and the experimental conditions of the cationic photopo‐lymerization on the rates was also studied using real‐time infrared spectroscopy. © 1995 John Wiley & Sons, Inc.

Cis-Diaminedichloroplatinum(II) complexes reversibly bound to water-soluble polyaspartamide carriers for chemotherapeutic applications. II: Platinum coordination to ethylenediamine ligands attached to poly(ethylene oxide)-grafted carrier polymers

In continuation of previous investigations aiming at the development of macromolecular metal complexes for biomedical use, this communication describes poly(alkylene oxide)-grafted polymeric platinum complexes. The platinum-containing macromolecules are obtained from presynthesized polyaspartamide carriers bearing poly(ethylene/propylene oxide) side chains and hydroxyethyl side groups as hydrosolubilizing units in addition to ethylenediamine side group terminals for metal coordination. Platination is brought about by treatment of the carriers with tetrachloroplatinate(II) ion in aqueous solution at 25–60°C. pH 4–6. The polymeric products, purified by dialysis in aqueous solution, are isolated by freeze-drying in yields of 60–80%. Platinum contents are in the range of 4–15%. The metal is bound to the carrier through chelation with the ethylenediamine ligands, forming square-planarcis-dichloroethylenediamine-platinum(II) complex species as side-chain terminals. Initially, the product polymers dissolve smoothly in water. Although on room-temperature storage in the solid state they gradually turn insoluble as a consequence of intermolecular solid-state interaction, solubility is retained on low-temperature storage and in frozen aqueous solutions.

Hydroperoxides as pseudohalides: oxidation, oxidative alkylation, acylation and arylation of acrylonitrile

New general syntheses, based on free-radical oxidative alkylation, acylation and arylation of acrylonitrile, in the presence of ButO2H, are reported; the concept of the peroxy group as a pseudohalide is suggested to explain these new reactions.

Aufbau, Stabilisierung und Spaltung von Rohölemulsionen (Teil II) / Composition, stabilisation and cleavage of crude oil emulsions (part II)

The choice of the surfactant plays an important role for the cleavage of water-in-oil emulsions. There is a modular system of special chemicals, whose components serve to formulate demulsifiers, which usually meat the demands. In some cases the performance of the demulsifiers consisting of alkoxylated systems is within a very narrow range dependent on the amount of alkylene oxide. In most fields of application, it is possible to tailormake alkoxylates. We were able to show that in some cases the simple addition of a polyglycole accelerates the demulsifying process, while the polyglycole itself has no demulsifying activity. Viscosity measurements have shown that even products wich macroscopically had no demulsifying effect, actually influenced the performance of the interfacial film. Gel permeation chromatography is a suitable method to analyse condensation and polyaddition products

Novel catalyst system for the synthesis of poly(alkylene oxide) with controlled molecular weight

AbstractAn organoaluminum compound with bulky phenoxide groups as a Lewis acid can accelerate much the living polymerization of alkylene oxide initiated with aluminum porphyrin by the coordinative activation of the monomer. This concept can be extented to the polymerization initiated with aluminum Schiff base and tetraazaannulene complexes.

Water‐soluble polyamides as potential drug carriers. VIII. Poly(alkylene oxide)‐grafted polyaspartamides bearing ethylenediamine side‐group functions

AbstractIn continuation of previous investigations of aspartamide‐type polymers as drug carriers, polyaspartamides featuring hydrosolubilizing poly(alkylene oxide) side chains in addition to ethylenediamine side‐group functions as potential drug‐binding sites are synthesized from poly‐D,L‐succinimide by successive aminolytic ring‐opening steps. Yields are in the range of 45–55%. Depending on selected feed ratios, the target polymers contain both the poly(alkylene oxide) and the ethylenediamine groups in systematically varied proportions. Compositions are determined microanalytically and from relative band intensities of the 1H‐NMR spectra. The polymers dissolve smoothly and completely in aqueous media and thus fulfill the major design requirement of water solubility. © 1994 John Wiley & Sons, Inc.

On the application of an association model to blends of phenoxy and ether-containing polymers

An association model is used to predict phase behaviour in mixtures of poly(hydroxy ether) of bisphenol A (phenoxy) (PH) with poly(alkylene oxide)s, poly(vinyl alkyl ether)s, aromatic polyethers and related copolymers. Equilibrium constants and enthalpies corresponding to self-association of PH and interassociation of PH with the second component were calculated from a Fourier transform infra-red spectroscopy study of low molecular weight analogues in dilute solutions. Transferability of the association constants between model compounds and polymer blends, as well as model predictions of blend miscibility and phase diagrams, are discussed.

On the application of an association model to blends containing poly(hydroxy ether of bisphenol A)

The possibilities and shortcomings of the Painter-Coleman association model (PCAM) to predict some thermodynamic properties of polymer blends are explored. More specificity, enthalpies of mixing, excess heat capacities, melting point depressions in crystalline/amorphous blends, and the evolution of the T g with blend composition are simulated for blends of phenoxy (a copolymer of Bisphenol A and epichlorohydrin) (PH) with families of polymers, including poly(alkylene oxides), poly(vinyl alkyl ethers), aliphatic polyesters, and polymethacrylates. Results are compared with some previously reported experimental data

The Effect of Polymer Structure on the Gas Permeability of Model Polyurethanes

In the face of impending CFC elimination, a large variety of low-boiling alternate blowing agents have come under scrutiny for use in rigid foam insulation applications. The permeability of both the alternate blowing agent and atmospheric gases through the rigid foam thermoset polymer contributes to the rate at which the k-factor of the resulting foam deteriorates. In this study, a compression moulding method for synthesizing polymer films from polyurethane formulation components (a variety of diols with pure and polymeric methylenediphenyl diisocyanate) was developed and utilised to produce films containing distinct structural features. The permeabilities of the films to oxygen and carbon dioxide were then determined using a diffusion cell combined with either an infrared or coulombic detector. The effects on permeability of structural features such as diol molecular weight, alkylene oxide repeat unit, and isocyanate functionality are presented. Structural features determined to promote improved barrier performance in polymer films have been incorporated into a fully formulated foam system. Foam permeability and k-factor ageing comparisons were then made which demonstrate the improved foam barrier performance. The resulting structure/permeability correlations derived from these experiments will be useful in designing rigid foam polymers for use in alternate blowing agent applications.

Phase Diagrams and Microstructure of Ionic Microemulsion Systems Containing Various Monoalkyl Poly (oxyalkylene) Ethers

Partial phase diagrams and microstructures were investigated in a one-phase microemulsion region of sodium oleate/monoalkyl poly (oxyalkylene) ethers/water ternary systems by conductivity, freezefracture electron microscopy and pulsed field gradient spin-echo (PGSE) NMR measurements. The influence of n-decane and glycerol trioleate on the ternary phase diagrams was also examined. Monomethyl, ethyl and butyl poly (oxyethylene) ethers and monobutyl ethers having both ethylene oxide (EO) and propylene oxide (PO) groups with different alkylene oxide chain length were used for this purpose. Although similar one phase microemulsion regions appeared in the monobutyl poly (oxyethylene) ether ternary systems, the microemulsion regions shrunk on increasing EO chain length by adding n-decane and glycerol trioleate. The introduction of PO groups at the terminal position of ethers had a spreading effect on the one phase region even in quaternary systems. Transition from water-in-oil to oil-in-water microemulsions through bicontinuous structures was found to occur with increase in water content.

ChemInform Abstract: A Facile Ring Transformation of 5‐Aminopyrimidin‐4(3H)‐one into 2‐ Alkoxy‐1H‐imidazoles in the Presence of Oxidative Metal Salts and Alkyl Alcohols.

AbstractChemInform 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.

Copolymerization of epoxides and five‐membered cyclic carbonates in the presence of zinc coordination catalysts

AbstractAlkylene oxides like ethylene oxide (1a) and propylene oxide (1b) were reacted with alkylene carbonates like ethylene carbonate (2a) and propylene carbonate (2b) in the presence of catalysts based on diethylzine and polyphenols (pyrogallol, 4‐tert‐butylcatechin) and catalysts based on diethylzinc‐phenol at temperatures in the range of 35–100°C. Reaction products were characterized by means of elemental analysis, IR, 1H NMR and 13C NMR spectroscopy and molecular weight determinations. The products appeared to be the respective low‐molecular‐weight copolymers – poly[oxyalkylene‐co‐(alkylene carbonate)]s: poly[oxyethylene‐co‐(ethylene carbonate)] (3 aa), poly[oxyethylene‐co‐(propylene carbonate)] (3 ab), poly[oxypropylene‐co‐(ethylene carbonate)] (3 ba) and poly[oxypropylene‐co‐(propylene carbonate)] (3 bb). Copolymers obtained with diethylzinc‐polyphenol catalysts were of higher molecular weight than those obtained with diethylzinc‐phenol catalysts. They contained more than 50 mol‐% of alkylene oxide units. Predominant head‐to‐tail arrangement of these units including those connected via carbonate linkages was observed by means of NMR spectroscopy in the case of 3 bb.

Modification of poly(ethylene ether carbonate) polyols by transesterification

AbstractPoly(ethylene ether carbonate) polyols are the reaction products of alkylene carbonates or alkylene oxides and CO2 with alcoholic initiators. These polyols can be modified with aliphatic hydroxyl compounds by transesterification reactions. The modifier becomes chemically bound into the polymer during reaction and modifies the properties of the polyol. The extent of reaction is very easy to follow by size exclusion chromatography. Molecular weight is controlled by the molecular weight of the reactants and by their stoichiometry. This transesterification process is compared to the previously described transesterification/advancement process. The transesterification process has the advantage of using milder temperature conditions and runs at ambient pressures. Therefore, modifiers can be used in the transesterification process that are unstable or undergo different chemistry under the reaction conditions of the transesterification/advancement process. Although the modifiers used in the transesterification/advancement process must be less volatile than DEG, more volatile modifiers can be used in the transesterification process. The two processes compliment each other, allowing the preparation of a wide variety of modified poly(ethylene ether carbonate) polyols. These polyols are useful in polyurethane applications.

Synthesis and characterization of hydroxy‐terminated poly(alkylene oxides) by condensation polymerization of diols

AbstractAcid‐catalysed condensation polymerization of 1,6‐hexanediol, 1,8‐octanediol and 1,10‐decanediol was carried out in the 150–190°C temperature range in the presence of sulphuric acid or Nafion‐H resin, and the polymerizations were monitored by size‐exclusion chromatography. The products were identified as hydroxy‐terminated poly(alkylene oxides) by 1H and 13C NMR and IR spectroscopy. The polymers were obtained in 66–81% yield from both catalysts in the polymerizations of 1,8‐octanediol and 1,10‐decanediol. With 1,6‐hexanediol the polymer yields were 30 and 42‐56% in the presence of Nafion and sulphuric acid, respectively. These low yields were due to the formation of oxepane as confirmed by gas chromatographic analysis of volatile condensation products. Vapour pressure osmometry showed the number‐average molecular weight of polymers to be in the range 700‐2400, depending on the reaction time and temperature. The hydroxy functionality of the poly(alkylene oxides) was 2.0 as determined by vapour pressure osmometry and 1H NMR spectroscopy.

Oxidative alkylation of (η 5-C 5Me 5) 2TiR (R = Cl, Me, Et, CHCH 2, Ph, OMe, NC(H) tBu) to (η 5-C 5Me 5) 2Ti(Me)R by group 12 organometallic compounds MMe 2

Oxidative alkylation of Cp * 2TiX (Cp *: η 5-C 5Me 5; X = OMe, Cl, NC(H) tBu) and Cp * 2TiMe by CdMe 2 or ZnMe 2 gives diamagnetic Cp * 2Ti(Me)X and Cp * 2TiMe 2 respectively, and cadmium or zinc. The reactions of Cp * 2TiR (R = Et, CHCH 2, Ph) with MMe 2 (M = Cd, Zn) give statistical mixtures of Cp * 2Ti(Me)R, Cp * 2TiMe 2 and Cp * 2TiR 2. Dimethylmercury does not react with Cp * 2TiX.

Reactivity of 2(2-hydroxy-5-vinylphenyl)-2h-benzotriazole-methyl methacrylate copolymer towards alkyl and peroxy radicals in the solid state

The reactivity of 2(2-hydroxy-5-vinyl)2H-benzotriazole (2H5V) structural units in a copolymer with methyl methacrylate (MMA) with respect to alkyl or peroxy radicals in the solid phase was studied. Alkyl radicals were generated through mechanical degradation of the copolymer and peroxy radicals were obtained by oxidation of alkyl radicals. Formation of oxy radicals expected in 2H5V-MMA copolymer was not observed even in the presence of alkyl or peroxy radicals. The resistance of 2H5V structural units of a copolymer to both types of radicals is attributed to the stability of the structure of 2H5V which is probably assisted by hydrogen bonding.