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  • 1
    Electronic Resource
    Electronic Resource
    Interpenetrating polymer networks from polyurethanes and methacrylate polymers. II. Interpenetrating polymer networks with opposite charge groups (1984)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 1035-1042 
    Details
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Interpenetrating polymer networks (IPNs) with opposite charge groups (tertiary amine and carboxyl groups) made from polyurethanes and methacrylate polymers have been synthesized and their properties and morphology, studied. With increasing carboxyl group concentration the mechanical properties and compatibility between the component networks were significantly improved, possibly because of the negative (or zero) free energy produced by the interaction contribution between the tertiary amine groups in the polyurethanes and the carboxyl groups in the methacrylate polymers determined by differential scanning calorimetry (DSC) and scanning electron microscopy (SEM). The improved molecular mixing in these IPNs was thought to be due to the influence of the opposite charge groups in these systems.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1984.170220504
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  • 2
    Electronic Resource
    Electronic Resource
    Interpenetrating polymer networks from polyurethanes and methacrylate polymers. I. Effect of molecular weight of polyols and NCO/OH ratio of urethane prepolymers on properties and morphology of IPNs (1983)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 21 (1983), S. 2547-2557 
    Details
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Two types of reinforced elastomeric interpentrating polymer network (IPN) were prepared by simultaneous polymerization and crosslinking in solution. The first type consisted of polyurethane-poly(methyl methacrylate) (PU/PMMA), and the second, of polyurethane-poly(methyl methacrylate-methacrylic acid) PU/P(MMA-MAA) of constant composition (90/10) and (80/20) by weight, respectively. The members of each type differed in the NCO/OH ratio of the PU prepolymer and the molecular weight (MW) of the polyol in the PU component because we wished to investigate systematically the effect of changing the NCO/OH ratio and MW of the polyol on the mechanical properties and morphology of the resulting IPNs. The mechanical properties, particularly the modulus of both tyes of IPN, increased with increasing NCO/OH ratio and decreased with increasing MW of the polyol in the PU. The morphology of the IPNs was studied by differential scanning calorimetry (DSC) and scanning electron microscopy (SEM). Improved phase compatibility and decreasing extent of phase separation was observed in both types of IPN with increasing NCO/OH ratio and decreasing MW of the polyol used in the PU. These results may imply that improved interpenetration results from increasing the NCO/OH ratio and decreasing the MW of the polyol in the PU component. The fact that the effect is more pronounced with the type of PU-P(MMA-MAA) IPN can be rationalized as due to the additional hydrogen bonding between the carbonyl in the carboxyl groups and the urethane or urea groups in the PU component.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1983.170210835
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  • 3
    Electronic Resource
    Electronic Resource
    Polyurethane ionomers. I. Structure-properties relationships of polyurethane ionomers (1984)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 29 (1984), S. 2467-2479 
    Details
    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: The influence of chemical structure on mechanical properties of polyurethane ionomers (PU ionomers) has been examined. NCO-terminated prepolymers prepared from primarily 4,4-methylene bis(phenyl isocyanate) (MDI) and poly(oxytetramethylene) glycol (PTMO) were chain extended with tertiary amine-containing diols and the ionomers obtained by quaternization of the prepolymers. The N-methyldiethanolamine chain extender gave the best physical properties. The mechanical properties of the PU ionomers were improved with decreasing chain length of PTMO and with increasing concentration of quaternary ammonium centers (or NCO/OH ratio of PU prepolymers). A lower degree of quaternization resulted in a decrease in the mechanical properties of the resulting PU ionomers, but their properties could be improved by post-quaternization. The adhesion of the PU ionomers to aluminum and the glass transition temperature increased with increasing concentration of quaternizing centers.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/app.1984.070290804
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  • 4
    Electronic Resource
    Electronic Resource
    Polyurethane cationomers. I. Structure-properties relationships (1988)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 1609-1620 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Polyurethane (PU) cationomers have been synthesized by quaternizing tertiary amine-containing linear polyurethanes using different quaternizers containing acid groups. The effect of chemical structure of PU cationomers on the physical properties was studied. The mechanical properties of PU cationomers were improved with decreasing molecular weight of poly(caprolactone) glycol, and increasing concentration of quaternary ammonium. Decreasing the carbon number in the alkyl group of the N-alkyl diethanol-amine chain-extenders, and using rigid symmetrical diisocyanates, the mechanical properties of the PU cationomers were increased. The effects of these factors on the glass transition temperature of PU cationomers were also examined. The mechanical properties of the PU cationomers decreased by immersion in water and recovered after removal of the water.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1988.080260611
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  • 5
    Electronic Resource
    Electronic Resource
    Polyurethane anionomers. I. Structure properties of polyurethane anionomers (1987)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 25 (1987), S. 2127-2137 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The influence of mono and divalent nontransition and transition metals on the glass transition and mechanical properties of polyurethane anionomers have been investigated. NCO-terminated prepolymer prepared from 4,4′-methylene-bis(phenyl isocyanate) (MDI) and poly(caprolactone) glycol (PCL) was chain extended with dimethylolpropionic acid (DMPA), and the anionomers obtained by neutralization of the prepolymer. The glass transition temperatures of polyurethane anionomers have been studied as a function of the counterion. From simple electrostatic considerations, it is shown that a linear relationship exists between the glass transition temperature and ionic potential (φ) for these particular materials. The relation is; Tg = Aφ + B. The mechanical properties are greatly affected by the type of the counterion, and in some cases, such as monovalent and nontransition metals, the mechanical properties of the anionomers improved by increasing the ionic potential. On the other hand, transition metals containing anionomers exhibited good mechanical properties but no relationship was observed between the mechanical properties and the ionic potential. The extent of water absorption of PU anionomers follows the same relative trends as the tensile strengths of the transition metals with filled and partially filled d-orbitals.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1987.080250809
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  • 6
    Electronic Resource
    Electronic Resource
    A review of kinetic studies on the formation of interpenetrating polymer networks (1996)
    New York, NY : Wiley-Blackwell
    Polymers for Advanced Technologies 7 (1996), S. 221-233 
    Details
    ISSN: 1042-7147
    Keywords: IPN ; kinetics ; simultaneity ; trommsdorff effect ; 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
    Notes: Interpenetrating polymer networks (IPNs) are unique alloys of crosslinked polymers. This article reviews the studies on kinetic effects involved in IPN formation. Several investigators have studied the effect of kinetics of curing reactions on the morphology and properties of IPNs. It was found, in general, that the faster the rates of the respective chain extension and crosslinking reactions are and the closer they are to simultaneity, the more homogeneous are the IPNs. Other investigations revealed that the individual components sometimes can polymerize more rapidly in the IPN than alone, due to a “solvent effect” of the IPN. Effects of changing reaction variables, such as NCO/OH ratio, composition activators and temperature were used to study reaction kinetics as well as phase morphology by the Fourier transform infrared technique. Thermochemical techniques have been utilized to study the kinetics of IPN formation which influence phase separation. Small-angle X-ray scattering and small-angle neutron scattering techniques were used to estimate the extent of microheterogeneity of the phase domains in a study of the kinetics of phase separation in the IPNs.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
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  • 7
    Electronic Resource
    Electronic Resource
    Crosslinking kinetics studies on interpenetrating polymer network powder coatings (1996)
    New York, NY : Wiley-Blackwell
    Polymers for Advanced Technologies 7 (1996), S. 323-328 
    Details
    ISSN: 1042-7147
    Keywords: IPN ; powder coatings ; DSC ; computer simulation ; 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
    Notes: IPN powder coatings were prepared which were composed of (A) a pendant double bond-containing acrylic resin made by reacting m-isopropenyl-α-α-dimethylbenzyl isocyanate (TMI) and a hydroxyl-containing acrylic resin and (B) a bisphenol type epoxy resin of high molecular weight cured by means of a carboxylic acid-containing acrylic resin. Crosslinking kinetics studies were carried out by using a computerized differential scanning calorimeter (DSC). A computer program was designed to simulate the curing reactions of the IPN powder coatings by using the individual kinetic parameters obtained from DSC. The simulated results from the computer program are very close to the results from experimental thermograms (by DSC). Therefore, this methodology provides an efficient tool to simplify and predict kinetic studies of crosslinking reactions in current or new IPN powder coating systems.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
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    Paper (German National Licenses)
  • 8
    Electronic Resource
    Electronic Resource
    Recent studies on interpenetrating polymer networks (1985)
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 25 (1985), S. 758-764 
    Details
    ISSN: 0032-3888
    Keywords: Chemistry ; Chemical Engineering
    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: Recent investigations on interpenetrating polymer networks (IPNs) have included two component IPNs from polyurethanes and poly(methacrylates) and two component IPNs from polyurethanes and epoxies. All the IPNs were prepared by the simultaneous polymerization technique (SIN-IPNs). Two types of IPNs, polyurethane-poly(methyl methacrylate) (PU/PMMA) and polyurethane-poly(methyl methacrylate-methacrylic acid) (PU/PMMA-MAA) were prepared. Improved phase miscibility and decreasing extent of phase separation was observed in both types of IPNs with increasing the NCO/OH ratio, decreasing molecular weight of the polyol in the PU and introduction of charge groups. A comparison was made between full-IPNs, pseudo-IPNs, graft copolymers and related homopolymers from polyurethanes and epoxies. Increased compatibility in full-IPNs and graft copolymers was observed by means of DSC, SEM and was also further substantiated by a shift toward single Tgs as determined by dynamic mechanical spectroscopy. The introduction of opposite charge groups in two-component IPNs from polyurethanes and epoxies led to improved compatibility (no phase separation) and enhanced mechanical properties.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pen.760251206
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