Library

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Acta Polymerica 42 (1991), S. 597-599 
    ISSN: 0323-7648
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: Mittels Kleinwinkel-Laserlichtsreuung und viskosimetrichen Messungen wurden verdünnte Lösungen von Polyurethanfraktionen untersucht. Das Polymer wurde aus Butandiol und Hexamethylendiisocyanat hergestellt. Die Grenzviskositäten wurden über die MARK-HOUWINK-SAKURADA-Gleichung zu den Molekülmassen korreliert. Die Werte der Konstanten Km und a wurden ermittelt. Trotz des niedrigen Brechungsinkrementes von Polyurethan in Benzen konnten Molekülmassen bis herab zu 4300 gemessen werden.
    Notes: Low angle laser light scattering and viscosity studies were made on dilute solution of fractions of polyurethane prepared from butandiol and hexamethylene diisocyanate. The intrinsic viscosities were correlated to molecular weights by the MARK-HOUWINK-SAKURADA equation. The values of the constants Km and a have been determined. In spite of the low refractive index increment of polyurethane in benzene, molecular weights as low as 4300 could be measured.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    Springer
    Journal of thermal analysis and calorimetry 38 (1992), S. 1391-1398 
    ISSN: 1572-8943
    Keywords: adducts ; complexes ; 8-hydroxyquinoline
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Die hergestellten Addukte von [Mo(CN)8]3− und von [W(CN)8]3− mit 8-Hydroxyquinolin (Oxin) haben die allgemeine Formel K3[Mo(CN)8](C9H7ON)8·4H2O bzw. K3[W(CN)8](C9H7ON)6·3H2O. Die FTIR-Spektren beweisen die Gegenwart der (CN)- bzw. der Oxingruppen in den Adduktverbindungen durch die Peaks im Bereich 2047–2108 cm bzw. 1015–1461 cm−1. Die untere Region des FTIR-Spektrums zeigt die M=O Valenzschwingung, die obere Region (N-H) und (OH). Nichtkoordiniertes Wasser wird in diesen Addukten in einem einzigen Schritt bei 110°C abgegeben. Die Zersetzung der Adduktverbindungen beginnt bei 125°C und setzt sich in verschiedenen Schritten bis hin zu 850°C fort. Der zweite Schritt der Zersetzung wird durch die Abgabe von Oxinmolekülen beherrscht, wobei polymere Oxide der allgemeinen Formel K2OM2O5 (mitM= Mo oder W) als Pyrolyseprodukte erhalten werden.
    Notes: Abstract The adducts of [Mo(CN)8]3− and [W(CN)8]3− with 8-hydroxyquinoline (oxine) synthesized were of the type K3[Mo(CN)8]·(C9H7ON)8·4H2O and K3[W(CN)8]·(C9H7ON)6·3H2O. The FTIR spectra show the presence of the (CN) and oxine group in the adduct compounds through the peaks in the range 2047–2108 cm−1 and 1015–1461 cnf−1 respectively. The lower region of FTIR spectra show the M=O stretching while the higher range to v(N-H) and v(OH) modes. The uncoordinated water in these adducts was removed at around 110°C in a single step. The decomposition of adduct compounds starts from 125°C and continues to higher temperatures upto 850°C in different stages. The second stage of decomposition was predominant with the removal of oxine molecules with the formation of polymeric oxide of the type K2O·M2O5 (whereM=Mo or W) obtained as the pyrolysis product.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 3
    Electronic Resource
    Electronic Resource
    Springer
    Journal of thermal analysis and calorimetry 46 (1996), S. 1763-1774 
    ISSN: 1572-8943
    Keywords: adducts ; complexes
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract The photoproduct of octacyanomolybdate(IV) and -tungstate(IV) with ethylenediamine and triethylenetetramine give complexes of the type K3[Mo(O2)(O)(OH)(C9H7ON)]·3C9H7ON I, K2[W(O2)(O) (C9H7ON)3] II and K3[Mo(CN)3(OH)4(C9H7ON)]·2C9H7ON·3H2O III with 8-quinolinol (oxine). The IR spectra of the complex III shows the presence ofv(CN) peaks in the range 2047–2108 cm−1 and oxine groupv(C-O) in the complex I, II and III in the range of 1100–1150 cm−1. The lower region of IR spectra shows the M=O stretching while the higher thev(N-H) andv(OH). Thermal studies show the removal of uncoordinated water at 131
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 4
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 188 (1987), S. 1195-1204 
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: A method of obtaining good quality ultrathin sections from nylon 6 bulk samples has been developed by using a special embedding technique and cryo-ultramicrotomy. The morphologies of nylon 6 processed by compression and injection molding and of reaction injection molded nylon 6 were studied in ultrathin sections of bulk samples by means of transmission electron microscopy. It was established that the spherulites of nylon 6 in bulk are built up from long flat ribbonlike lamellae. The thickness of the lamellae is in the range 50-60 Å. The width varies from 150 to 600 Å and depends on the type of nylon 6 and the method of processing. The length of the lamellae is relatively large approaching spherulite radii, extending often from the point of their origin up to the spherulite borders. Three or four neighboring lamellae within spherulites usually show similar orientation of their flat faces and form domains which can easily be mistaken for fibrils in light microscopy or low resolution electron microscopy.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 5
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 187 (1986), S. 431-439 
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The origin of the curious “inverted contrast” often observed in transmission electron micrographs of crazes in rubber-toughened thermoplastics was determined by using scanning transmission electron microscopy with X-ray fluorescence analysis. The “black crazes” seen in the micrographs contain high concentrations of osmium metal which is introduced through OsO4 used to stain the rubber phase. Treatment of stained sections with a strong oxidizing agent (NaIO4) removes a sufficient amount of osmium to reveal the commonly observed tufty craze microstructure with the expected contrast of light crazes in a darker background.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 6
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 23 (1979), S. 2893-2897 
    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 major degradative process in γ-irradiated cellulose acetate is chain scission. For the dry powder the Gs value (number of scissions per 100 eV of energy absorbed) was found to be 7.1. The water-swollen material was found to degrade at the higher rate of Gs = 9.45. Additions of ethanol and methanol to the water brought about reductions in Gs, whereas dissolved nitrous oxide produced an increase in Gs. The useful life of cellulose acetate reverse osmosis membranes exposed to γ radiation was estimated by observations of the water permeation rate during irradiation. Membrane breakdown occurred at 15 Mrad in pure water, but the dose to breakdown was extended to 83 Mrad in the presence of 4% methanol.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 7
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 55 (1995), S. 733-740 
    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: Interpenetrating polymer networks (IPNs) are a special type of polymer blend consisting of two polymer networks synthesized and/or cross-linked independently within each other. One potential approach for the preparation of composite materials from polymers having desirable physical characteristics obtained by modifying their surfaces with physiologically acceptable polymers involves IPN technology. An IPN based on a poly(ether urethane) and polydimethylsiloxane has been synthesized and charaterized using optical microscopy, dynamic mechanical analysis, and scanning electron microscopy. The stability of poly(ether urethane)/polydimethylsiloxane composites were studied in hydroxyl radical aqueous solutions over 30 weeks. The data suggest that these composites have good potential for biomedical applications. © 1995 John Wiley & Sons, Inc.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 8
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 48 (1993), S. 85-97 
    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: Normally brittle polystyrene (PS) can be toughened effectively by the inclusion of a few weight percent of low molecular weight polybutadiene (PB). The PB, which can be made to phase separate into submicron sized, randomly dispersed pools, locally plasticizes the glassy phase in the vicinity of a growing craze; the resulting reduction in craze flow stress and increased craze velocity lead to significant enhancement of toughness when strain rates are below approximately 10-1 s-1. Craze velocities were measured in PS containing 1 to 5 wt % of a low molecular weight PB (2300 g/mol). The results were compared to a version of the interface convolution mechanism for craze growth that has been modified to account for the localized plasticization effect of the low molecular weight diluent. Addition of 5 wt % PB led to craze velocities that are three orders of magnitude larger than observed for pure PS. The model deviated significantly from the experimental data at the higher and of the PB concentration range studied here, but it did exhibit the general form of the observed dependence of craze velocity on PB content. © 1993 John Wiley & Sons, Inc.
    Additional Material: 10 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 9
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 48 (1993), S. 1915-1992 
    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 object of this work was to investigate the effect of the introduction of pyridinium chain-ends in polytetrahydrofuran (PTHF) polymers on certain solid-state properties. A comparison of solid-state properties of methoxy-terminated (PTHF-OMe) with pyridinium bromide-terminated (PTHF-Py) polytetrahydrofuran polymers of virtually identical molecular weights was made. Crystallization studies and dynamic mechanical and stress-strain analyses have been undertaken. It was concluded that the introduction of the ionic pyridinium bromide groups to the PTHF polymers influenced the degree of crystallinity and this, in turn, affected other physical properties. © 1993 John Wiley & Sons, Inc.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 10
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 52 (1994), S. 1129-1135 
    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: Thermoplastic interpenetrating polymer networks (IPN) are mixtures of two physically crosslinked polymers. Thermoplastic IPNs were prepared by blending an SBS triblock elastomer with a 1,2-polybutadiene that was ionically-terminated at both ends. The morphologies of these IPNs were studied using differential scanning calorimetry and dynamic mechanical thermal analysis. It was concluded that the ionomer was incompatible with the SBS elastomer, since the Tgs of both the 1,2-polybutadiene from the ionomer and the essentially 1,4-polybutadiene from the SBS component were observable at temperatures that were close to those of the individual components. The addition of the polybutadiene material had, however, an influence on the relaxation processes of the polystyrene blocks. The polystyrene glass transition in the pure SBS copolymer is broadened by the interfacial region between polystyrene and polybutadiene. The low temperature shoulder was much more pronounced when the ion-terminated polybutadiene was present, indicating it has a preference to be located in these interfacial regions. © 1994 John Wiley & Sons, Inc.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...