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water soluble polymeric base

1.0 wt%안팍의 water solubility를 가지면서 basic한 polymer에는 어떤 것이 있습니까? 상품명도 괜찮고, chemical name도 상관없습니다. 부탁드립니다.
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    >1.0 wt%안팍의 water solubility를 가지면서 basic한 polymer에는 어떤 것이 있습니까? >상품명도 괜찮고, chemical name도 상관없습니다. >부탁드립니다. 1. Water-soluble photoresins based on polymeric azo compounds Matusche, P. (Technische Universitaet Muenchen) Nuyken, O. | Voit, B. | Van Damme, M. | Vermeersch, J. | De Winter, W. | Alaerts, L. Source: Reactive Polymers 24 3 Feb 1995 Elsevier Science B.V. p 271-278 0923-1137 Abstract: Polymeric azosulfonates lose their water solubility when exposed to UV light due to decomposition of the azo function. This effect can be used in water-based photoprinting processes. Water-soluble copolymers of azosulfonate containing repeat units and methyl methacrylate have been alternatively synthesized by a polymer-analogous reaction [1,2] and by direct copolymerization [3]. Both polymer types have been evaluated for application as photoresins in offset printing processes. The polymer made by copolymerization is superior and shows excellent results for photosensitivity, resolution, film-forming properties, and development in water, as well as for thermal and moisture storage stability. In English 7 Refs. EI95042665147 2. Mathematical description of metal retention with water-soluble polymers during membrane filtration Golovanov, V.I. (Chelyabinsk Univ) Shkinev, V.M. | Geckeler, K.E. | Bayer, E. Source: Separation Science and Technology v 28 n 10 Jul 1993 p 1887-1898 0149-6395 Abstract: A theoretical approach to the description of metal retention and enrichment in aqueous solution by soluble polymeric reagents during membrane filtration is proposed. The metal retention data obtained experimentally may be explained by using mathematical models based on the theory of kinetics of reactions in partially open systems. In English 8 Refs EI93081053242 3. Targetable polymeric drugs Kopecek, J. (Univ of Utah) Kopeckova, P. Source: Polymer Preprints, Division of Polymer Chemistry, American Chemical Society v 31 n 2 Aug 1990 Publ by ACS p 196-197 0032-3934 Abstract: Biocompatible soluble synthetic polymers show excellent potential as drug carriers for targeted and site-specific drug delivery. We have been developing targetable polymeric prodrugs based on N-(2-hydroxypropyl)methacrylamide copolymers for several, years. Attaching drug to water-soluble macromolecules limits their cellular capture to the pinocytic route and renders them lysosomotropic. Targeting can be achieved by conjugating the polymer bound drug to a targeting moiety having a structure complementary to cell surface antigens or receptors. The activation of polymer bound drugs in secondary lysosomes can be achieved either by enzymes or light. Synthetic water-soluble copolymers also have potential for use in oral drug delivery. Polymeric prodrugs may be synthesized where the bond between drug and carrier macromolecule matches the specificity of enzymes present in a specific region of the gastrointestinal tract. In English 21 Refs 4. Synthetic polymeric flocculants improve separation process efficiency Waller, Steve (Ciba Specialty Chemicals) Source: Water & Wastewater International v 14 n 1 Feb 1999 PennWell Publ Co 2pp Abstract: Use of synthetic polymeric flocculantas can greatly improve the efficiency of any solid/liquid separation process, particularly in sewage and wastewater treatment. At present, majority of flocculants are synthetic water-soluble organic polymers of very high molecular weight consisting of molecules that are long straight chains. Most of these flocculants are based on polyacrylamide and its derivatives. In English EI99044648254 5. Solid-state light-emitting devices based on the tris-chelated ruthenium(II) complex: 3. High efficiency devices via a layer-by-layer molecular-level blending approach Wu, A. (Massachusetts Inst of Technology) Yoo, D. | Lee, J.-K. | Rubner, M.F. Source: Journal of the American Chemical Society 121 20 May 26 1999 p 4883-4891 0002-7863 Abstract: High efficiency, solid-state light-emitting devices have been fabricated from a water soluble, polymeric ruthenium (II) complex, Ru(bpy)32+ polyester, via the use of a layer-by-layer processing scheme. Spin-coated devices of this material were found to produce maximum luminance levels of 250-300 cd/m2 with an external quantum efficiency of 0.2% photons/electron. Devices based on sequentially adsorbed layers of the Ru(bpy)32+ polyester and poly(acrylic acid), on the other hand, exhibit external quantum efficiencies in the 1-3% range with a maximum light output of 40-50 cd/m2. These high device efficiencies were obtained by optimizing the relative amounts of Ru(bpy)32+ polyester and poly(acrylic acid) incorporated into the film via a layer-by-layer molecular-level blending approach. Through this type of control, it was also possible to create compositionally graded heterostructures and to produce devices that emit light only in the forward or reverse bias or that were completely symmetrical (similar light output, current flow, and efficiency in both forward and reverse bias). In English 6. Extraction of extracellular polymers from activated sludge using a cation exchange resin Frolund, Bo (Aalborg Univ) Palmgren, Rikke | Keiding, Kristian | Nielsen, Per Halkjaer Source: Water Research 30 8 Aug 1996 Pergamon Press Inc p 1749-1758 0043-1354 Abstract: The extraction of water soluble extracellular polymeric substances (EPS) from activated sludge was investigated. The extraction procedure was based upon cation exchange using a cation exchange resin (CER). Activated sludge from two different types of treatment plants responded very similarly to the extraction procedure. The EPS yield was enhanced by increasing the stirring intensity, the amounts of CER added and by increasing the extraction time. For the chosen extraction procedure the yield was twice as high as other commonly used procedures. Analytical methods for analysis of sludge and EPS extracts are compared and discussed. In English 50 Refs. EI96093325435 7. Salt-steered partitioning of proteins in polymeric two-phase systems based on N,N-dimethylformamide Truust, Helle (Univ of Lund) Johansson, Gote Source: Journal of Chromatography B v 711 n 1-2 Jun 26 1998 Elsevier Sci B.V. p 117-126 0378-4347 Abstract: The polymeric two-phase (liquid-liquid) system, based on N,N-dimethylformamide (DMFA) and the two polymers Ficoll and poly(ethylene glycol), has been investigated. The partitioning of the water-insoluble protein fraction, zein (from corn), was affected by the addition of various salts that were soluble in DMFA. The effect of the salts has been correlated to their partition coefficients. The data have been fitted to a theory for partitioning of polyelectrolytes in aqueous two-phase systems. The two-phase system has been used for partial fractionation of zein by counter-current distribution. In English 13 Refs. EI98114454192 8. Synthesis of biologically active polyethylene glycol derivatives. A review Topchiyeva, I.N. (Lomonosov State Univ) Source: Polymer Science USSR (English Translation of Vysokomolekulyarnye Soyedineniya Series A) v 32 n 5 1990 p 833-851 0032-3950 Abstract: PEG is soluble in water, non-toxic and chemically inert in relation to biological structures. These properties make it a convenient polymeric base for immobilizing various biologically active compounds. Different ways of introducing biologically active compounds into PEG are considered. The traditional way is to modify PEG by the end of hydroxyl groups leading to synthesis of telechelics. Approaches to means of obtaining telechelics with high functionality based on allowance for the reactivity of the end hydroxyl groups in PEG and the phase state of the polymers in solution are discussed. A new approach to the synthesis of PEG is to use the reactions of free-radical substitution permitting the introduction of reactive groups as side groups into the main chain of polyethers as demonstrated by homo- and block copolymers of ethylene oxide. A fundamentally different way of synthesizing PEG is to conduct anionic polymerization of ethylene oxide allowing the functional groups to be introduced as starting or terminal at the stage of chain initiation and termination. Methods of synthesizing labelled PEGs and also ways of analysing the functional groups in PEG are examined. In English 74 Refs EI91110355247 9. Multicompartment polymeric micelles based on hydrocarbon and fluorocarbon polymerizable surfactants Stahler, Katrin (Inst Charles Sadron (CRM)) Selb, Joseph | Candau, Francoise Source: Langmuir 15 22 1999 ACS p 7565-7576 0743-7463 Abstract: The synthesis of multicompartment polymeric micelles (MCPMs) has been achieved by aqueous radical terpolymerization of a water-soluble monomer (acrylamide) with both hydrocarbon (H) and fluorocarbon (F) surfactants (surfmers) in the micellar state. The selected H- and F-surfmers are specified. Their mutual incompatibility in aqueous solution has been checked by conductivity and surface tension experiments. Two cmc values are found, in favor of the coexistence of two distinct types of micelles at surfactant concentrations above 1 mmol/L (second cmc) over a broad composition range. The solubilization properties of the pure and mixed surfactant systems have been studied for different hydrophobic probes. Significant differences in the solubilization capacity occur due to the nature of the dye, of the surfactant, and of the micelle shape and composition. A kinetic study on the incorporation behavior of the H- and F-surfmers in the polyacrylamide backbone during a batch polymerization shows a compositional drift as a function of conversion which is attributed to micellar effects. A semicontinuous process has been designed which allows the correction for this compositional drift. The presence of well-segregated H- and F-microdomains in terpolymers could be inferred from viscosity and fluorescence experiments. Furthermore, the solubilization of decalin is enhanced in terpolymer solutions with respect to that of copolymer solutions. This was attributed to the formation of larger hydrocarbon cores in the former case due to repulsive H/F interactions in the polymeric chains. In English 61 Refs. 10. Novel versatile process for the production of polymer foams Shastri, V.P. (Massachusetts Inst of Technology) Martin, I. | Langer, R. Source: Materials Research Society Symposium - Proceedings 550 Nov 30-Dec 4 1998 1999 Sponsored by: GelTex Pharmaceuticals, Inc.; Johnson and Johnson Professional, Inc.; New Jersey Center for Biomaterials and Medical Devices; Reprogenesis; et al. Materials Research Society p 149-153 0272-9172 Abstract: Porous polymeric media are used in several applications such as solid supports for separations and catalysis, as well as biomedical applications such as vascular grafts and wound dressings. We have developed a novel versatile process to produce polymeric cellular solids. This process which is based on a phase extraction-co-polymer precipitation is applicable to a wide range of polymer systems including water soluble polymers. It is capable of yielding polymer foams of high porosity (> 90%) and excellent mechanical characteristics in a very short time (less than 2 hours) without limitations in foam thickness. Polymer foam with such characteristics have great utility in tissue engineering applications. We have successfully explored polymer foams of biocompatible polymers produced by the presented approach for bone and cartilage engineering using bone marrow stromal cells. In English 14 Refs. 11. Amphiphilic polyethylene glycol derivatives: Long-circulating micellar carriers for therapeutic and diagnostic agents Torchilin, Vladimir P. (Massachusetts General Hospital and Harvard Medical Sch) Trubetskoy, Vladimir S. Source: Polymer Preprints, Division of Polymer Chemistry, American Chemical Society v 38 n 1 Apr 1997 ACS p 545-546 0032-3934 Abstract: A class of amphiphilic polymers which are known to form polymeric micelles in aqueous solutions are proposed as drug carriers. Amphiphilic AB-type copolymer can form polymeric micelles with hydrophobic block making up a particle core, while polyethylene glycols (PEG) blocks shape surrounding water-soluble and sterically-protective PEG blocks. Several advantages of PEG-based micelles as drug carrier over other particulates include small size, enhanced micelle permeability across physiological barriers, long circulation provided by PEG shell and targetability upon certain surface modification. In English 6 Refs. 12. Lysosomal degradability of poly(α-amino acids) Chiu, Hsin-Cheng (Natl Chung Hsing Univ) Kopeckova, Pavla | Deshmane, Sharad S. | Kopecek, Jindrich Source: Journal of Biomedical Materials Research v 34 n 3 Mar 5 1997 p 381-392 0021-9304 Abstract: The lysosomal degradability of poly(α-amino acids) based on poly(L-glutamic acid) and its derivatives/copolymers was evaluated to gain insight into the subcellular fate of the macromolecules as water soluble polymeric drug carriers. The results indicate that both the incorporation of hydrophobic comonomers and modification of the carboxylic groups of glutamic acid side chains with hydroxyalkylamine increase the lysosomal degradability of the copolymers. Decreased lysosomal degradability of L-glutamic acid copolymers containing tripeptides terminated in p-nitroanilide (drug model) in the side chains confirmed that drug conjugation alters the degradation pattern of the polymeric carriers. The percentages of the enzymatic release of p-nitroaniline from its polymeric complex with time is relatively independent of the contents of the tripeptidyl p-nitroanilides attached to the polymeric conjugates. Determination of the degradation products by electrospray mass spectroscopy showed that no fragments less than 103 D were generated by lysosomal enzymes, whereas the main degradation products by papain and chymotrypsin were tripeptides and tetrapeptides. The conclusions derived from these data strongly suggest that these macromolecules, if used as lysosomotropic drug carriers, may accumulate in the lysosomes and limit their usefulness in some applications. In English 54 Refs. 16. Chelating resins VII: Studies on chelating resins of formaldehyde and furfuraldehyde-condensed phenolic Schiff base derived from 4,4 prime -diaminodiphenylsulphone and o-hydroxyacetophenone Samal, S. (Ravenshaw Coll) Mohapatra, N.K. | Acharya, S. | Dey, R.K. Source: Reactive and Functional Polymers v 42 n 1 1999 Elsevier Science B.V. p 37-52 1381-5148 Abstract: The synthesis, characterization and capacity studies of two chelating resins having multiple functional groups capable of coordinating to several metal ions are reported. The resins were synthesized by condensing phenolic Schiff bases derived from 4,4 prime -diaminodiphenylsulphone and o-hydroxyacetophenone with formaldehyde/furfuraldehyde. The polymeric Schiff bases were found to form complexes readily with several transition metal ions. The resins were completely soluble in dimethyl sulphoxide, tetrahydrofuran, partially soluble in CHCl3, CCl4, and insoluble in water. On formation of the polychelate with transition metal ions such as Cu(II) and Ni(II), the solubility sharply decreased. The Schiff bases, resins and the polychelates were characterized by FTIR, FT 1H-NMR, 13C-NMR and XRD studies, and thermal analyses like TGA and DSC. From FTIR studies the phenolic oxygen and the imine nitrogen of the resins were found to be the coordination sites. The 1H-NMR data indicated the presence of bridging methylene and terminal methylol functions in the formaldehyde-condensed Schiff base. The thermal stability of the resins and the polychelates was compared by analyzing TG data which provided the various kinetic parameters like activation energy, frequency factor and entropy changes associated with the thermal decomposition. The DSC and XRD data indicated that the incorporation of the metal ions significantly enhanced the degree of crystallinity. The adsorption characteristics of the resins towards Cu(II) and Ni(II) in dilute aqueous solutions were followed spectrophotometrically. Cu(II) was seen to undergo preferential adsorption in a mixture of Cu(II) and Ni(II). The effects of contact time, pH, temperature, the size of the sorbents and the concentration of the metal ions in solution on the metal uptake behavior of the resins were studied. In English 38 Refs. EI99104830024 18. Interactions of the water-soluble poly(N-maleyl glycine-co-acrylic acid) as polychelatogen with metal ions in aqueous solution Pizarro, G. del C. (Univ of Los Lagos) Marambio, O.G. | Rivas, B.L. | Geckeler, K.E. Source: Journal of Macromolecular Science - Pure and Applied Chemistry A34 8 Aug 1997 p 1483-1491 1060-1325 Abstract: The metal complexation of water-soluble poly(N-maleyl glycine-co-acrylic acid) with Co(II), Zn(II), Ni(II), Cu(II), Fe(II), Cd(II, Pb(II), and Sr(II) ions was investigated in aqueous phase using the Liquid-Phase Polymer-Based Retention (LPR) technique. The water-soluble P(MG-co-AA) copolymer was shown to be useful for the retention of different inorganic ions in conjunction with membrane filtration and their separation from ions not bound to the polymeric reagent. At higher pH, the water-soluble copolymer can be applied to the separation and preconcentration of many metal ions. Maximum capacity values of the copolymer for copper(II) were determined at different pH. Viscometric measure-ments of the copolymers were performed in the presence of the nine metal ions at different pH values. In English EI97083771369 20. Flux decay and rejection during micro- and ultra-filtration of hydrophobically modified water-soluble polymers Wakeman, R.J. (Univ of Exeter) Akay, G. Source: Journal of Membrane Science v 91 n 1-2 May 20 1994 Publ by Elsevier Science Publishers B.V. p 145-152 0376-7388 Abstract: Crossflow filtration of anionic and cationic hydrophobically modified water-soluble polymers was studied using polyether sulphone membranes with varying pore sizes. New data on the permeate flux rates and rejections of these polymer solutions are presented. It was found that the pseudo-gel polarization concentration increases with increasing polymer solubility. The steady state permeate flux decays linearly with log (MWCO). A minimum molecular weight cut off (MMWCO) can be identified by extrapolating the steady state permeate flux to zero. The MMWCO is well below the molecular weight cut off (MWCO) based on the random coil size of the macromolecule. It is shown that the MMWCO should be based on the size of the small axis of the rod-like extended molecule, which can orientate in the flow field during passage through the pores. This model also explains why the polymer rejection increases with increasing permeate flux. In English 20 Refs. EI94081359375
    >1.0 wt%안팍의 water solubility를 가지면서 basic한 polymer에는 어떤 것이 있습니까? >상품명도 괜찮고, chemical name도 상관없습니다. >부탁드립니다. 1. Water-soluble photoresins based on polymeric azo compounds Matusche, P. (Technische Universitaet Muenchen) Nuyken, O. | Voit, B. | Van Damme, M. | Vermeersch, J. | De Winter, W. | Alaerts, L. Source: Reactive Polymers 24 3 Feb 1995 Elsevier Science B.V. p 271-278 0923-1137 Abstract: Polymeric azosulfonates lose their water solubility when exposed to UV light due to decomposition of the azo function. This effect can be used in water-based photoprinting processes. Water-soluble copolymers of azosulfonate containing repeat units and methyl methacrylate have been alternatively synthesized by a polymer-analogous reaction [1,2] and by direct copolymerization [3]. Both polymer types have been evaluated for application as photoresins in offset printing processes. The polymer made by copolymerization is superior and shows excellent results for photosensitivity, resolution, film-forming properties, and development in water, as well as for thermal and moisture storage stability. In English 7 Refs. EI95042665147 2. Mathematical description of metal retention with water-soluble polymers during membrane filtration Golovanov, V.I. (Chelyabinsk Univ) Shkinev, V.M. | Geckeler, K.E. | Bayer, E. Source: Separation Science and Technology v 28 n 10 Jul 1993 p 1887-1898 0149-6395 Abstract: A theoretical approach to the description of metal retention and enrichment in aqueous solution by soluble polymeric reagents during membrane filtration is proposed. The metal retention data obtained experimentally may be explained by using mathematical models based on the theory of kinetics of reactions in partially open systems. In English 8 Refs EI93081053242 3. Targetable polymeric drugs Kopecek, J. (Univ of Utah) Kopeckova, P. Source: Polymer Preprints, Division of Polymer Chemistry, American Chemical Society v 31 n 2 Aug 1990 Publ by ACS p 196-197 0032-3934 Abstract: Biocompatible soluble synthetic polymers show excellent potential as drug carriers for targeted and site-specific drug delivery. We have been developing targetable polymeric prodrugs based on N-(2-hydroxypropyl)methacrylamide copolymers for several, years. Attaching drug to water-soluble macromolecules limits their cellular capture to the pinocytic route and renders them lysosomotropic. Targeting can be achieved by conjugating the polymer bound drug to a targeting moiety having a structure complementary to cell surface antigens or receptors. The activation of polymer bound drugs in secondary lysosomes can be achieved either by enzymes or light. Synthetic water-soluble copolymers also have potential for use in oral drug delivery. Polymeric prodrugs may be synthesized where the bond between drug and carrier macromolecule matches the specificity of enzymes present in a specific region of the gastrointestinal tract. In English 21 Refs 4. Synthetic polymeric flocculants improve separation process efficiency Waller, Steve (Ciba Specialty Chemicals) Source: Water & Wastewater International v 14 n 1 Feb 1999 PennWell Publ Co 2pp Abstract: Use of synthetic polymeric flocculantas can greatly improve the efficiency of any solid/liquid separation process, particularly in sewage and wastewater treatment. At present, majority of flocculants are synthetic water-soluble organic polymers of very high molecular weight consisting of molecules that are long straight chains. Most of these flocculants are based on polyacrylamide and its derivatives. In English EI99044648254 5. Solid-state light-emitting devices based on the tris-chelated ruthenium(II) complex: 3. High efficiency devices via a layer-by-layer molecular-level blending approach Wu, A. (Massachusetts Inst of Technology) Yoo, D. | Lee, J.-K. | Rubner, M.F. Source: Journal of the American Chemical Society 121 20 May 26 1999 p 4883-4891 0002-7863 Abstract: High efficiency, solid-state light-emitting devices have been fabricated from a water soluble, polymeric ruthenium (II) complex, Ru(bpy)32+ polyester, via the use of a layer-by-layer processing scheme. Spin-coated devices of this material were found to produce maximum luminance levels of 250-300 cd/m2 with an external quantum efficiency of 0.2% photons/electron. Devices based on sequentially adsorbed layers of the Ru(bpy)32+ polyester and poly(acrylic acid), on the other hand, exhibit external quantum efficiencies in the 1-3% range with a maximum light output of 40-50 cd/m2. These high device efficiencies were obtained by optimizing the relative amounts of Ru(bpy)32+ polyester and poly(acrylic acid) incorporated into the film via a layer-by-layer molecular-level blending approach. Through this type of control, it was also possible to create compositionally graded heterostructures and to produce devices that emit light only in the forward or reverse bias or that were completely symmetrical (similar light output, current flow, and efficiency in both forward and reverse bias). In English 6. Extraction of extracellular polymers from activated sludge using a cation exchange resin Frolund, Bo (Aalborg Univ) Palmgren, Rikke | Keiding, Kristian | Nielsen, Per Halkjaer Source: Water Research 30 8 Aug 1996 Pergamon Press Inc p 1749-1758 0043-1354 Abstract: The extraction of water soluble extracellular polymeric substances (EPS) from activated sludge was investigated. The extraction procedure was based upon cation exchange using a cation exchange resin (CER). Activated sludge from two different types of treatment plants responded very similarly to the extraction procedure. The EPS yield was enhanced by increasing the stirring intensity, the amounts of CER added and by increasing the extraction time. For the chosen extraction procedure the yield was twice as high as other commonly used procedures. Analytical methods for analysis of sludge and EPS extracts are compared and discussed. In English 50 Refs. EI96093325435 7. Salt-steered partitioning of proteins in polymeric two-phase systems based on N,N-dimethylformamide Truust, Helle (Univ of Lund) Johansson, Gote Source: Journal of Chromatography B v 711 n 1-2 Jun 26 1998 Elsevier Sci B.V. p 117-126 0378-4347 Abstract: The polymeric two-phase (liquid-liquid) system, based on N,N-dimethylformamide (DMFA) and the two polymers Ficoll and poly(ethylene glycol), has been investigated. The partitioning of the water-insoluble protein fraction, zein (from corn), was affected by the addition of various salts that were soluble in DMFA. The effect of the salts has been correlated to their partition coefficients. The data have been fitted to a theory for partitioning of polyelectrolytes in aqueous two-phase systems. The two-phase system has been used for partial fractionation of zein by counter-current distribution. In English 13 Refs. EI98114454192 8. Synthesis of biologically active polyethylene glycol derivatives. A review Topchiyeva, I.N. (Lomonosov State Univ) Source: Polymer Science USSR (English Translation of Vysokomolekulyarnye Soyedineniya Series A) v 32 n 5 1990 p 833-851 0032-3950 Abstract: PEG is soluble in water, non-toxic and chemically inert in relation to biological structures. These properties make it a convenient polymeric base for immobilizing various biologically active compounds. Different ways of introducing biologically active compounds into PEG are considered. The traditional way is to modify PEG by the end of hydroxyl groups leading to synthesis of telechelics. Approaches to means of obtaining telechelics with high functionality based on allowance for the reactivity of the end hydroxyl groups in PEG and the phase state of the polymers in solution are discussed. A new approach to the synthesis of PEG is to use the reactions of free-radical substitution permitting the introduction of reactive groups as side groups into the main chain of polyethers as demonstrated by homo- and block copolymers of ethylene oxide. A fundamentally different way of synthesizing PEG is to conduct anionic polymerization of ethylene oxide allowing the functional groups to be introduced as starting or terminal at the stage of chain initiation and termination. Methods of synthesizing labelled PEGs and also ways of analysing the functional groups in PEG are examined. In English 74 Refs EI91110355247 9. Multicompartment polymeric micelles based on hydrocarbon and fluorocarbon polymerizable surfactants Stahler, Katrin (Inst Charles Sadron (CRM)) Selb, Joseph | Candau, Francoise Source: Langmuir 15 22 1999 ACS p 7565-7576 0743-7463 Abstract: The synthesis of multicompartment polymeric micelles (MCPMs) has been achieved by aqueous radical terpolymerization of a water-soluble monomer (acrylamide) with both hydrocarbon (H) and fluorocarbon (F) surfactants (surfmers) in the micellar state. The selected H- and F-surfmers are specified. Their mutual incompatibility in aqueous solution has been checked by conductivity and surface tension experiments. Two cmc values are found, in favor of the coexistence of two distinct types of micelles at surfactant concentrations above 1 mmol/L (second cmc) over a broad composition range. The solubilization properties of the pure and mixed surfactant systems have been studied for different hydrophobic probes. Significant differences in the solubilization capacity occur due to the nature of the dye, of the surfactant, and of the micelle shape and composition. A kinetic study on the incorporation behavior of the H- and F-surfmers in the polyacrylamide backbone during a batch polymerization shows a compositional drift as a function of conversion which is attributed to micellar effects. A semicontinuous process has been designed which allows the correction for this compositional drift. The presence of well-segregated H- and F-microdomains in terpolymers could be inferred from viscosity and fluorescence experiments. Furthermore, the solubilization of decalin is enhanced in terpolymer solutions with respect to that of copolymer solutions. This was attributed to the formation of larger hydrocarbon cores in the former case due to repulsive H/F interactions in the polymeric chains. In English 61 Refs. 10. Novel versatile process for the production of polymer foams Shastri, V.P. (Massachusetts Inst of Technology) Martin, I. | Langer, R. Source: Materials Research Society Symposium - Proceedings 550 Nov 30-Dec 4 1998 1999 Sponsored by: GelTex Pharmaceuticals, Inc.; Johnson and Johnson Professional, Inc.; New Jersey Center for Biomaterials and Medical Devices; Reprogenesis; et al. Materials Research Society p 149-153 0272-9172 Abstract: Porous polymeric media are used in several applications such as solid supports for separations and catalysis, as well as biomedical applications such as vascular grafts and wound dressings. We have developed a novel versatile process to produce polymeric cellular solids. This process which is based on a phase extraction-co-polymer precipitation is applicable to a wide range of polymer systems including water soluble polymers. It is capable of yielding polymer foams of high porosity (> 90%) and excellent mechanical characteristics in a very short time (less than 2 hours) without limitations in foam thickness. Polymer foam with such characteristics have great utility in tissue engineering applications. We have successfully explored polymer foams of biocompatible polymers produced by the presented approach for bone and cartilage engineering using bone marrow stromal cells. In English 14 Refs. 11. Amphiphilic polyethylene glycol derivatives: Long-circulating micellar carriers for therapeutic and diagnostic agents Torchilin, Vladimir P. (Massachusetts General Hospital and Harvard Medical Sch) Trubetskoy, Vladimir S. Source: Polymer Preprints, Division of Polymer Chemistry, American Chemical Society v 38 n 1 Apr 1997 ACS p 545-546 0032-3934 Abstract: A class of amphiphilic polymers which are known to form polymeric micelles in aqueous solutions are proposed as drug carriers. Amphiphilic AB-type copolymer can form polymeric micelles with hydrophobic block making up a particle core, while polyethylene glycols (PEG) blocks shape surrounding water-soluble and sterically-protective PEG blocks. Several advantages of PEG-based micelles as drug carrier over other particulates include small size, enhanced micelle permeability across physiological barriers, long circulation provided by PEG shell and targetability upon certain surface modification. In English 6 Refs. 12. Lysosomal degradability of poly(α-amino acids) Chiu, Hsin-Cheng (Natl Chung Hsing Univ) Kopeckova, Pavla | Deshmane, Sharad S. | Kopecek, Jindrich Source: Journal of Biomedical Materials Research v 34 n 3 Mar 5 1997 p 381-392 0021-9304 Abstract: The lysosomal degradability of poly(α-amino acids) based on poly(L-glutamic acid) and its derivatives/copolymers was evaluated to gain insight into the subcellular fate of the macromolecules as water soluble polymeric drug carriers. The results indicate that both the incorporation of hydrophobic comonomers and modification of the carboxylic groups of glutamic acid side chains with hydroxyalkylamine increase the lysosomal degradability of the copolymers. Decreased lysosomal degradability of L-glutamic acid copolymers containing tripeptides terminated in p-nitroanilide (drug model) in the side chains confirmed that drug conjugation alters the degradation pattern of the polymeric carriers. The percentages of the enzymatic release of p-nitroaniline from its polymeric complex with time is relatively independent of the contents of the tripeptidyl p-nitroanilides attached to the polymeric conjugates. Determination of the degradation products by electrospray mass spectroscopy showed that no fragments less than 103 D were generated by lysosomal enzymes, whereas the main degradation products by papain and chymotrypsin were tripeptides and tetrapeptides. The conclusions derived from these data strongly suggest that these macromolecules, if used as lysosomotropic drug carriers, may accumulate in the lysosomes and limit their usefulness in some applications. In English 54 Refs. 16. Chelating resins VII: Studies on chelating resins of formaldehyde and furfuraldehyde-condensed phenolic Schiff base derived from 4,4 prime -diaminodiphenylsulphone and o-hydroxyacetophenone Samal, S. (Ravenshaw Coll) Mohapatra, N.K. | Acharya, S. | Dey, R.K. Source: Reactive and Functional Polymers v 42 n 1 1999 Elsevier Science B.V. p 37-52 1381-5148 Abstract: The synthesis, characterization and capacity studies of two chelating resins having multiple functional groups capable of coordinating to several metal ions are reported. The resins were synthesized by condensing phenolic Schiff bases derived from 4,4 prime -diaminodiphenylsulphone and o-hydroxyacetophenone with formaldehyde/furfuraldehyde. The polymeric Schiff bases were found to form complexes readily with several transition metal ions. The resins were completely soluble in dimethyl sulphoxide, tetrahydrofuran, partially soluble in CHCl3, CCl4, and insoluble in water. On formation of the polychelate with transition metal ions such as Cu(II) and Ni(II), the solubility sharply decreased. The Schiff bases, resins and the polychelates were characterized by FTIR, FT 1H-NMR, 13C-NMR and XRD studies, and thermal analyses like TGA and DSC. From FTIR studies the phenolic oxygen and the imine nitrogen of the resins were found to be the coordination sites. The 1H-NMR data indicated the presence of bridging methylene and terminal methylol functions in the formaldehyde-condensed Schiff base. The thermal stability of the resins and the polychelates was compared by analyzing TG data which provided the various kinetic parameters like activation energy, frequency factor and entropy changes associated with the thermal decomposition. The DSC and XRD data indicated that the incorporation of the metal ions significantly enhanced the degree of crystallinity. The adsorption characteristics of the resins towards Cu(II) and Ni(II) in dilute aqueous solutions were followed spectrophotometrically. Cu(II) was seen to undergo preferential adsorption in a mixture of Cu(II) and Ni(II). The effects of contact time, pH, temperature, the size of the sorbents and the concentration of the metal ions in solution on the metal uptake behavior of the resins were studied. In English 38 Refs. EI99104830024 18. Interactions of the water-soluble poly(N-maleyl glycine-co-acrylic acid) as polychelatogen with metal ions in aqueous solution Pizarro, G. del C. (Univ of Los Lagos) Marambio, O.G. | Rivas, B.L. | Geckeler, K.E. Source: Journal of Macromolecular Science - Pure and Applied Chemistry A34 8 Aug 1997 p 1483-1491 1060-1325 Abstract: The metal complexation of water-soluble poly(N-maleyl glycine-co-acrylic acid) with Co(II), Zn(II), Ni(II), Cu(II), Fe(II), Cd(II, Pb(II), and Sr(II) ions was investigated in aqueous phase using the Liquid-Phase Polymer-Based Retention (LPR) technique. The water-soluble P(MG-co-AA) copolymer was shown to be useful for the retention of different inorganic ions in conjunction with membrane filtration and their separation from ions not bound to the polymeric reagent. At higher pH, the water-soluble copolymer can be applied to the separation and preconcentration of many metal ions. Maximum capacity values of the copolymer for copper(II) were determined at different pH. Viscometric measure-ments of the copolymers were performed in the presence of the nine metal ions at different pH values. In English EI97083771369 20. Flux decay and rejection during micro- and ultra-filtration of hydrophobically modified water-soluble polymers Wakeman, R.J. (Univ of Exeter) Akay, G. Source: Journal of Membrane Science v 91 n 1-2 May 20 1994 Publ by Elsevier Science Publishers B.V. p 145-152 0376-7388 Abstract: Crossflow filtration of anionic and cationic hydrophobically modified water-soluble polymers was studied using polyether sulphone membranes with varying pore sizes. New data on the permeate flux rates and rejections of these polymer solutions are presented. It was found that the pseudo-gel polarization concentration increases with increasing polymer solubility. The steady state permeate flux decays linearly with log (MWCO). A minimum molecular weight cut off (MMWCO) can be identified by extrapolating the steady state permeate flux to zero. The MMWCO is well below the molecular weight cut off (MWCO) based on the random coil size of the macromolecule. It is shown that the MMWCO should be based on the size of the small axis of the rod-like extended molecule, which can orientate in the flow field during passage through the pores. This model also explains why the polymer rejection increases with increasing permeate flux. In English 20 Refs. EI94081359375
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