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  • 1
    ISSN: 0887-624X
    Keywords: phospholipid analogous acrylamide monomers ; long chain alkyl groups ; phosphatidylcholine analogues ; stacked bilayer structure ; liquid crystalline behavior ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A series of new phospholipid analogous acrylamide monomers (4a-e) containing long alkyl chains as hydrophobic groups and containing phosphatidylcholine analogues as hydrophilic group were synthesized in high yields. The homopolymerizations and copolymerization (4b with 4e) were carried out in the presence of a radical initiator. The structures and thermal properties of these polymers were investigated by x-ray diffraction analysis, DSC, and polarizing microscopy measurements. It has been revealed that these homopolymers (5b, 5c, and 5d) which bear saturated long-hydrocarbon chains in the side chains exhibited not only orderly stacked bilayer structures at room temperature but also clear liquid crystalline behavior within a wide temperature range. The viscosity behavior of all polymers was found similar to usual polyelectrolytes in porlar solvent. The polymers obtained were also characterized by 1H-NMR, IR, and melting point, respectively. © 1996 John Wiley & Sons, Inc.
    Additional Material: 11 Ill.
    Type of Medium: Electronic Resource
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  • 2
    ISSN: 0021-8995
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Two kinds of phospholipid analogous compounds, methacrylate monomers (4a-b) and acrylamide monomers (5a-b), were prepared and polymerized with a radical initiator in water at room temperature. The viscosity behavior of these charged polymers were investigated in the presence or absence of inorganic salts, and the found inherent viscosity [η] of amide polymer (poly7a) is higher than those of ester polymers (poly6a1 and poly6b). On the other hand, the radical copolymerization of monomer 5b with acrylamide (AAm) was also carried out in water. Based on the x-ray analyses, it is proposed that some of the obtained polymers show ordered bilayer structures in condensed phase. Furthermore, the thermal properties were studied by DSC and TG-DTA measurements. © 1996 John Wiley & Sons, Inc.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
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  • 3
    ISSN: 0021-8995
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Polyrethanes, based on 2-[bis(2-hydroxyethyl)methylammoni]ethylstearylphosphate, alone or together with 1,4-butanediol as the chain extender, poly(isoprene) diol and 4,4′-methylenediphenyl diisocyanate, were prepared. These segmented phospholipid polyurethanes were characterized by IR, elemental analyses, and gel permeation chromatography. The polyurethane, with both phospholipid diol and 1,4-butanediol as the chain extender, was further investigated by differential scanning calorimetry, x-ray diffraction, scanning electron microscopy, plasma contact and clotting time. An x-ray diffraction measurement for the polymer shows a intense scattering at 79.3 Å corresponding to the length of soft segments, which is hydrophobic poly(isoprene), and a weak diffuse scattering at 5.1 Å corresponding to the distance between the hydrophobic poly (isoprene) layers. The hemocompatibilities of the polymer were evaluated by platelet rich plasma contacting studies and by scanning electron microscopy using medical grade poly(vinyl chloride) as control. The hot-pressed films of the polymer exhibit a favorable surface in terms of platelet adhesion, and the morphology of adhered platelets undergoes to a relatively lower degree of variation compared to poly(vinyl chloride). Moreover, the clotting time of the polymer in contact with human platelet rich plasma was 220, 100, and 86 s for the phospholipid-based polyurethane, poly(vinyl chloride), and glass, respectively. © 1996 John Wiley & Sons, Inc.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
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  • 4
    ISSN: 1022-1352
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Two polyimides, PI(BA-TD) and PI(6FDA-TD), based on an aromatic diamine (TD) and two aromatic dianhydrides (BA, 6FDA) were synthesized. They were characterized by viscosity, FT-IR, and X-ray photoelectron spectroscopy (XPS) measurements. XPS results reveal that the binding energy of C1s, N1s, and O1s in PI(BA-TD) is lower than that in PI(6FDA-TD). The synthesized polyimides form stable and homogeneous thin films on an ITO electrode, functioning as good hole transporting materials for organic electroluminescent (EL) devices. The double-layered EL devices consisting of a hole transporting layer of these polyimides and an emitting layer of the tris(8-quinolinolato)aluminium complex exhibit a peak emission wavelength in the bright green at 521-525 nm. Furthermore, a maximum luminance of 97 cd/m2 was achieved at a voltage of 15 V with a current density of 192 mA/cm2 for the EL device using PI(BA-TD) as a hole transporting layer. The phenomenon of an extended luminance of these EL devices was also found when a voltage higher than 15 V was applied.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
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  • 5
    ISSN: 1022-1336
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Three new amphiphilic phospholipid diols containing hydrophilic phosphatidylcholine analogues in the main chains and hydrophobic octadecyl, hexadecyl or dodecyl alkyl groups in the side chains were synthesized. The typical phospholipid diol based on an octadecyl group was further reacted with diisocyanates such as hexamethylene diisocyanate (HDI), 2,4-tolylene diisocyanate (TDI) and 4,4′-methylenediphenyl diisocyanate (MDI), respectively. Preliminary studies suggest that polyurethane based on MDI shows a viscosity behavior similar to common polyelectrolytes and exhibits a therm decomposition peak at 244°C due to the phospholipid moiety and a melting point at 218°C.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
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  • 6
    ISSN: 1022-1352
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: New hydrophobic-hydrophilic microphase-separated block segmented copoly(urethane-urea)s were synthesized by introducing hydrophobic polybutadienes as the soft segments and 4,4′-methylenediphenyl diisocyanate, hexamethylene diisocyanate, ethylenediamine, and a hydrophilic phosphatidylcholine analogue as the hard segments in the backbones of these polymers. The results of ATR-IR and XPS show the coexistence of phosphatidylcholine analogues and polybutadienes on the surface of cast films of the synthesized poly(urethane-urea)s. Furthermore, TEM cross sectional observation of the cast film PBDP-1370 indicates that it possesses a hydrophilic-hydrophobic microphase-separated domain structure.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
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  • 7
    ISSN: 1022-1352
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: A series of phospholipid diols based on different lengths of alkyl chains such as eicosyl, stearyl, cetyl, lauryl, octyl, and butyl was synthesized and characterized. The phospholipid diols were subjected a polyaddition polymerization with hexamethylene diisocyanate. The haemocompatibilities of the resulting phospholipid polyurethanes were evaluated by platelet rich plasma contacting experiments and viewed by scanning electron microscopy. The polymers with alkyl chains of 20, 18, 16, and 12 carbon atoms showed much better haemocompatibilities than those with alkyl chains of 8 and 4 carbon atoms.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
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  • 8
    ISSN: 0887-624X
    Keywords: phosphatidylcholine analogous diamine ; interfacial polycondensation ; phospholipid analogous polyamides ; solvent-resistibility ; crystallinity ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Polyamides (4a-b and 5a-b) were synthesized from interfacial polycondensation of novel diamine containing phosphatidylcholine analogous moiety, hexamethylene diamine with adipoyl chloride, or sebacoyl chloride in the interface of water and carbon tetrachloride at room temperature. The characterizations of synthesized diamine and polyamides were carried out with FT-NMR, or IR spectral method, elemental analysis, and melting point measurements, respectively. These polyamides obtained are insoluble in any normal solvents. From the results of X-ray diffraction analysis and POM observation, it was revealed that the polyamide 4b was prepared with high molecular weight, while polyamide 4a obtained seemed to have low molecular weight. For copolymers 5a and 5b, X-ray reflections from only adipoyl or sebacoyl chloride parts were observed as in crystalline state. In addition, thermal properties were also studied by DSC and transmitted light intensity measurements. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 3065-3074, 1997
    Additional Material: 7 Ill.
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