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  • 1
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    Skp2 targeting suppresses tumorigenesis by Arf-p53-independent cellular senescence (2010)
    Nature Publishing Group (NPG)
    Details
    Publikationsdatum: 2010-03-20
    Beschreibung: Cellular senescence has been recently shown to have an important role in opposing tumour initiation and promotion. Senescence induced by oncogenes or by loss of tumour suppressor genes is thought to critically depend on induction of the p19(Arf)-p53 pathway. The Skp2 E3-ubiquitin ligase can act as a proto-oncogene and its aberrant overexpression is frequently observed in human cancers. Here we show that although Skp2 inactivation on its own does not induce cellular senescence, aberrant proto-oncogenic signals as well as inactivation of tumour suppressor genes do trigger a potent, tumour-suppressive senescence response in mice and cells devoid of Skp2. Notably, Skp2 inactivation and oncogenic-stress-driven senescence neither elicit activation of the p19(Arf)-p53 pathway nor DNA damage, but instead depend on Atf4, p27 and p21. We further demonstrate that genetic Skp2 inactivation evokes cellular senescence even in oncogenic conditions in which the p19(Arf)-p53 response is impaired, whereas a Skp2-SCF complex inhibitor can trigger cellular senescence in p53/Pten-deficient cells and tumour regression in preclinical studies. Our findings therefore provide proof-of-principle evidence that pharmacological inhibition of Skp2 may represent a general approach for cancer prevention and therapy.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2928066/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2928066/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Lin, Hui-Kuan -- Chen, Zhenbang -- Wang, Guocan -- Nardella, Caterina -- Lee, Szu-Wei -- Chan, Chia-Hsin -- Yang, Wei-Lei -- Wang, Jing -- Egia, Ainara -- Nakayama, Keiichi I -- Cordon-Cardo, Carlos -- Teruya-Feldstein, Julie -- Pandolfi, Pier Paolo -- R01 CA082328/CA/NCI NIH HHS/ -- R01 CA082328-13/CA/NCI NIH HHS/ -- R01 MD004038/MD/NIMHD NIH HHS/ -- England -- Nature. 2010 Mar 18;464(7287):374-9. doi: 10.1038/nature08815.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Cancer Biology and Genetics Program, Sloan-Kettering Institute, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, New York, New York 10021, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/20237562" target="_blank"〉PubMed〈/a〉
    Schlagwort(e): Activating Transcription Factor 4/metabolism ; Adenovirus E1A Proteins/genetics/metabolism ; Animals ; *Cell Aging/drug effects ; *Cell Transformation, Neoplastic/drug effects ; Cells, Cultured ; Cyclin-Dependent Kinase Inhibitor p16/deficiency/genetics/metabolism ; Cyclin-Dependent Kinase Inhibitor p21/metabolism ; Cyclin-Dependent Kinase Inhibitor p27/metabolism ; Fibroblasts ; Male ; Mice ; PTEN Phosphohydrolase/deficiency/genetics/metabolism ; Prostate/cytology/metabolism ; Prostatic Neoplasms/drug therapy/pathology/prevention & control ; Proto-Oncogene Proteins p21(ras)/genetics/metabolism ; S-Phase Kinase-Associated Proteins/antagonists & inhibitors/genetics/*metabolism ; SKP Cullin F-Box Protein Ligases/metabolism ; Tumor Suppressor Protein p53/deficiency/metabolism
    Print ISSN: 0028-0836
    Digitale ISSN: 1476-4687
    Thema: Biologie , Chemie und Pharmazie , Medizin , Allgemeine Naturwissenschaft , Physik
    Publiziert von Nature Publishing Group (NPG)
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  • 2
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    TLR recognition of self nucleic acids hampers glucocorticoid activity in lupus (2010)
    Nature Publishing Group (NPG)
    Details
    Publikationsdatum: 2010-06-19
    Beschreibung: Glucocorticoids are widely used to treat patients with autoimmune diseases such as systemic lupus erythematosus (SLE). However, regimens used to treat many such conditions cannot maintain disease control in the majority of SLE patients and more aggressive approaches such as high-dose methylprednisolone pulse therapy are used to provide transient reductions in disease activity. The primary anti-inflammatory mechanism of glucocorticoids is thought to be NF-kappaB inhibition. Recognition of self nucleic acids by toll-like receptors TLR7 and TLR9 on B cells and plasmacytoid dendritic cells (PDCs) is an important step in the pathogenesis of SLE, promoting anti-nuclear antibodies and the production of type I interferon (IFN), both correlated with the severity of disease. Following their activation by self-nucleic acid-associated immune complexes, PDCs migrate to the tissues. We demonstrate, in vitro and in vivo, that stimulation of PDCs through TLR7 and 9 can account for the reduced activity of glucocorticoids to inhibit the IFN pathway in SLE patients and in two lupus-prone mouse strains. The triggering of PDCs through TLR7 and 9 by nucleic acid-containing immune complexes or by synthetic ligands activates the NF-kappaB pathway essential for PDC survival. Glucocorticoids do not affect NF-kappaB activation in PDCs, preventing glucocorticoid induction of PDC death and the consequent reduction of systemic IFN-alpha levels. These findings unveil a new role for self nucleic acid recognition by TLRs and indicate that inhibitors of TLR7 and 9 signalling could prove to be effective corticosteroid-sparing drugs.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2964153/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2964153/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Guiducci, Cristiana -- Gong, Mei -- Xu, Zhaohui -- Gill, Michelle -- Chaussabel, Damien -- Meeker, Thea -- Chan, Jean H -- Wright, Tracey -- Punaro, Marilynn -- Bolland, Silvia -- Soumelis, Vassili -- Banchereau, Jacques -- Coffman, Robert L -- Pascual, Virginia -- Barrat, Franck J -- 2R44AI066483-02/AI/NIAID NIH HHS/ -- P50 AR054083/AR/NIAMS NIH HHS/ -- P50 AR054083-01/AR/NIAMS NIH HHS/ -- P50 AR054083-010001/AR/NIAMS NIH HHS/ -- P50 AR054083-010002/AR/NIAMS NIH HHS/ -- P50 AR054083-019001/AR/NIAMS NIH HHS/ -- P50 AR054083-02/AR/NIAMS NIH HHS/ -- P50 AR054083-020001/AR/NIAMS NIH HHS/ -- P50 AR054083-020002/AR/NIAMS NIH HHS/ -- P50 AR054083-029001/AR/NIAMS NIH HHS/ -- P50 AR054083-03/AR/NIAMS NIH HHS/ -- P50 AR054083-030001/AR/NIAMS NIH HHS/ -- P50 AR054083-030002/AR/NIAMS NIH HHS/ -- P50 AR054083-04/AR/NIAMS NIH HHS/ -- P50 AR054083-040001/AR/NIAMS NIH HHS/ -- P50 AR054083-040002/AR/NIAMS NIH HHS/ -- P50 AR054083-04S1/AR/NIAMS NIH HHS/ -- P50 AR054083-05/AR/NIAMS NIH HHS/ -- P50 AR054083-050001/AR/NIAMS NIH HHS/ -- P50 AR054083-050002/AR/NIAMS NIH HHS/ -- P50-ARO54083-01CORT/PHS HHS/ -- R44 AI066483/AI/NIAID NIH HHS/ -- R44 AI066483-02/AI/NIAID NIH HHS/ -- U19 AI082715/AI/NIAID NIH HHS/ -- U19 AI082715-01/AI/NIAID NIH HHS/ -- U19 AI082715-017348/AI/NIAID NIH HHS/ -- U19 AI082715-017351/AI/NIAID NIH HHS/ -- U19 AI082715-02/AI/NIAID NIH HHS/ -- U19 AI082715-027348/AI/NIAID NIH HHS/ -- U19 AI082715-027351/AI/NIAID NIH HHS/ -- U19 AI082715-03/AI/NIAID NIH HHS/ -- U19-AI082715-01/AI/NIAID NIH HHS/ -- England -- Nature. 2010 Jun 17;465(7300):937-41. doi: 10.1038/nature09102.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Dynavax Technologies Corporation, 2929 Seventh Street, Suite 100, Berkeley, California 94710, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/20559388" target="_blank"〉PubMed〈/a〉
    Schlagwort(e): Adolescent ; Animals ; Autoantibodies/immunology ; Cell Survival/drug effects ; Cells, Cultured ; Child ; Dendritic Cells/*drug effects ; Disease Models, Animal ; Female ; Glucocorticoids/*pharmacology ; Humans ; Interferon-alpha/immunology ; Interferons/immunology ; Lupus Erythematosus, Systemic/*physiopathology ; Male ; Membrane Glycoproteins/immunology ; Mice ; Mice, Inbred C57BL ; NF-kappa B/immunology ; Nucleic Acids/*immunology ; Toll-Like Receptor 7/*immunology ; Toll-Like Receptor 9/*immunology ; Up-Regulation
    Print ISSN: 0028-0836
    Digitale ISSN: 1476-4687
    Thema: Biologie , Chemie und Pharmazie , Medizin , Allgemeine Naturwissenschaft , Physik
    Publiziert von Nature Publishing Group (NPG)
    Standort Signatur Erwartet Verfügbarkeit
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  • 3
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    Fungal pathogen reduces potential for malaria transmission (2005)
    American Association for the Advancement of Science (AAAS)
    Details
    Publikationsdatum: 2005-06-11
    Beschreibung: Using a rodent malaria model, we found that exposure to surfaces treated with fungal entomopathogens following an infectious blood meal reduced the number of mosquitoes able to transmit malaria by a factor of about 80. Fungal infection, achieved through contact with both solid surfaces and netting for durations well within the typical post-feed resting periods, was sufficient to cause 〉90% mortality. Daily mortality rates escalated dramatically around the time of sporozoite maturation, and infected mosquitoes showed reduced propensity to blood feed. Residual sprays of fungal biopesticides might replace or supplement chemical insecticides for malaria control, particularly in areas of high insecticide resistance.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Blanford, Simon -- Chan, Brian H K -- Jenkins, Nina -- Sim, Derek -- Turner, Ruth J -- Read, Andrew F -- Thomas, Matt B -- Wellcome Trust/United Kingdom -- New York, N.Y. -- Science. 2005 Jun 10;308(5728):1638-41.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Institutes of Evolution, Immunology, and Infection Research, School of Biological Sciences, Ashworth Laboratories, University of Edinburgh, Edinburgh EH9 3JT Scotland, UK.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/15947189" target="_blank"〉PubMed〈/a〉
    Schlagwort(e): Animals ; Anopheles/*microbiology/*parasitology/physiology ; Blood ; Feeding Behavior ; *Hypocreales/pathogenicity/physiology ; Insect Vectors/microbiology/parasitology/physiology ; Malaria/parasitology/prevention & control/*transmission ; Mice ; *Mitosporic Fungi/pathogenicity/physiology ; *Pest Control, Biological ; Plasmodium chabaudi/*growth & development/physiology ; Spores, Fungal ; Virulence
    Print ISSN: 0036-8075
    Digitale ISSN: 1095-9203
    Thema: Biologie , Chemie und Pharmazie , Informatik , Medizin , Allgemeine Naturwissenschaft , Physik
    Publiziert von American Association for the Advancement of Science (AAAS)
    Standort Signatur Erwartet Verfügbarkeit
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  • 4
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    The E3 ligase TRAF6 regulates Akt ubiquitination and activation (2009)
    American Association for the Advancement of Science (AAAS)
    Details
    Publikationsdatum: 2009-08-29
    Beschreibung: Akt signaling plays a central role in many biological functions, such as cell proliferation and apoptosis. Because Akt (also known as protein kinase B) resides primarily in the cytosol, it is not known how these signaling molecules are recruited to the plasma membrane and subsequently activated by growth factor stimuli. We found that the protein kinase Akt undergoes lysine-63 chain ubiquitination, which is important for Akt membrane localization and phosphorylation. TRAF6 was found to be a direct E3 ligase for Akt and was essential for Akt ubiquitination, membrane recruitment, and phosphorylation upon growth-factor stimulation. The human cancer-associated Akt mutant displayed an increase in Akt ubiquitination, in turn contributing to the enhancement of Akt membrane localization and phosphorylation. Thus, Akt ubiquitination is an important step for oncogenic Akt activation.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3008763/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3008763/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Yang, Wei-Lei -- Wang, Jing -- Chan, Chia-Hsin -- Lee, Szu-Wei -- Campos, Alejandro D -- Lamothe, Betty -- Hur, Lana -- Grabiner, Brian C -- Lin, Xin -- Darnay, Bryant G -- Lin, Hui-Kuan -- R01 CA149321/CA/NCI NIH HHS/ -- R01 CA149321-02/CA/NCI NIH HHS/ -- New York, N.Y. -- Science. 2009 Aug 28;325(5944):1134-8. doi: 10.1126/science.1175065.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Molecular and Cellular Oncology, The University of Texas M. D. Anderson Cancer Center, Houston, TX 77030, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/19713527" target="_blank"〉PubMed〈/a〉
    Schlagwort(e): Amino Acid Motifs ; Animals ; Apoptosis ; Cell Line ; Cell Line, Tumor ; Cell Membrane/*metabolism ; Humans ; Insulin-Like Growth Factor I/pharmacology ; Interleukin-1beta/pharmacology ; Lipopolysaccharides/pharmacology ; Mice ; Neoplasm Transplantation ; Neoplasms, Experimental/metabolism ; Phosphatidylinositol Phosphates/metabolism ; Phosphorylation ; Proto-Oncogene Proteins c-akt/chemistry/*metabolism ; *Signal Transduction ; TNF Receptor-Associated Factor 6/genetics/*metabolism ; Transplantation, Heterologous ; Ubiquitin-Protein Ligases/*metabolism ; Ubiquitination
    Print ISSN: 0036-8075
    Digitale ISSN: 1095-9203
    Thema: Biologie , Chemie und Pharmazie , Informatik , Medizin , Allgemeine Naturwissenschaft , Physik
    Publiziert von American Association for the Advancement of Science (AAAS)
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  • 5
    Digitale Medien
    Digitale Medien
    Thermal degradation of polymers. Part XX. The effect of thermal ageing on thermal diffusivity and hardness of polyquinazolones (1978)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 22 (1978), S. 2197-2206 
    Details
    ISSN: 0021-8995
    Schlagwort(e): Chemistry ; Polymer and Materials Science
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Maschinenbau , Physik
    Notizen: Pre-polymers prepared from 4,4′-diaminodiphenyl-3,3′-dicarboxylic acid and aromatic diacetamido compounds have been cyclized under optimized conditions. The thermal diffusivity and hardness of these materials have been evaluated. The effect of thermal ageing on these parameters and weight loss has also been investigated. Changes in these parameters have been related to the possible structural changes occurring within these systems. These changes are discussed in terms of the potential use of these materials in tribological applications.
    Zusätzliches Material: 5 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/app.1978.070220812
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  • 6
    Digitale Medien
    Digitale Medien
    A model for molecular weights in vinyl acetate emulsion polymerization (1988)
    Hoboken, NJ : Wiley-Blackwell
    AIChE Journal 34 (1988), S. 840-848 
    Details
    ISSN: 0001-1541
    Schlagwort(e): Chemistry ; Chemical Engineering
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Werkstoffwissenschaften, Fertigungsverfahren, Fertigung
    Notizen: The continuous stirred tank emulsion polymerization of vinyl acetate has shown oscillatory behavior in conversion, particle size, molecular weight, and polydispersity during polymerization. The kinetics in vinyl acetate emulsion polymerization are especially complex because of chain transfer to polymer and monomer and the terminal double bond reaction. A nonsteady-state model to predict the average molecular weights is developed for this polymerization system. Improved results are achieved by inclusion of the effects of polymer chain initiation and termination by absorbed radicals. It is found that the observed oscillations are closely related to the radical diffusion and desorption rates that are involved in a heterogeneous initiation mechanism. The molecular weights and polydispersities are successfully predicted by the model. The nature of the oscillations in these properties is examined.
    Zusätzliches Material: 8 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/aic.690340514
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  • 7
    Digitale Medien
    Digitale Medien
    Morphology development in polymer blends (1992)
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 32 (1992), S. 1814-1823 
    Details
    ISSN: 0032-3888
    Schlagwort(e): Chemistry ; Chemical Engineering
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Maschinenbau , Physik
    Notizen: The major morphological changes during polymer blending occur during the initial softening stage. This work explains the evolution of phase morphology of polymer blends from pellets to submicron particles in a co-rotating twin-screw extruder. The extruder was opened and blend samples were taken along its length. The major phase component was extracted by means of a selective solvent so that the dispersed phase morphology could be viewed directly by using scanning electron microscopy. The two systems studied were 80:20 polystyrene/amorphous polyamide and 80:20 polystyrene/polypropylene. In both systems, the initial morphology consisted of sheets of dispersed phase. Holes form in the sheets, and these holes grow as a result of interfacial tension forces until they coalesce with each other, forming thin ligaments. These fluid ligaments are unstable and break up via mixer shear forces. Very large changes in dispersed phase size are observed during the softening stage. The particle size changes less after the polymers are completely melted. The extruder results are compared to results from a batch mixer. The same dispersed phase sheeting mechanism is seen in the initial morphology in the batch mixer and the breakup of the dispersed phase domains parallels the breakup seen in the extruder.
    Zusätzliches Material: 8 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/pen.760322404
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  • 8
    Digitale Medien
    Digitale Medien
    Thermal properties of tropical wood-polymer composites (1991)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 43 (1991), S. 2057-2065 
    Details
    ISSN: 0021-8995
    Schlagwort(e): Chemistry ; Polymer and Materials Science
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Maschinenbau , Physik
    Notizen: Wood-polymer composites (WPC) of Geronggang (GE; Cratoxylon arborescens), a light tropical hardwood, impregnated with methyl methacrylate (MMA), styrene-co-acrylonitrile (3: 2; STAN), methyl methacrylate-co-bis (2-chloroethyl) vinyl phosphonate (3 : 1; MVP) and methyl methacrylate-co-bis (chloropropyl)-2-propene phosphonate (3:1;MPP), were prepared by in situ polymerization using γ-radiation or catalyst-heat treatment. Thermal characterization of these WPC by limiting oxygen index measurements (LOI), thermogravimetry (TG), and differential scanning calorimetry (DSC) showed that the impregnants greatly modified the wood properties. The LOI values of the GE-MVP and GE-MPP composites were much higher than that for GE and the other composites, indicating the effectiveness of the phosphonates as flame retardants. Concomitantly, the flaming characteristics also compared favorably against that for GE and the other composites. The decomposition temperature and maximum rate of weight loss determined by TG for GE-MVP and GE-MPP were substantially reduced, whereas the char yields were greatly higher. These observations again indicate that phosphonates imparted flame-retarding properties to their composites. The thermal properties of GE-MMA and GE-STAN composites were not vastly different from that of untreated GE. Flame retardancy in the phosphonate-containing composites was effected through both the condensed- and gaseous-phase mechanisms due to the presence of phosphorus and chlorine, respectively. Indication of grafting of polymer to wood was found for GE-STAN, GE-MVP, and GE-MPP composites, but not for GE-MMA. Composites prepared by γ-radiation or by the catalyst-heat treatment had similar thermal characteristics.
    Zusätzliches Material: 3 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/app.1991.070431113
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  • 9
    Digitale Medien
    Digitale Medien
    Molecular weight distribution in continuous stirred tank vinyl acetate emulsion polymerization (1989)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 37 (1989), S. 3315-3327 
    Details
    ISSN: 0021-8995
    Schlagwort(e): Chemistry ; Polymer and Materials Science
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Maschinenbau , Physik
    Notizen: Emulsion polymerization typically produces polymers of high molecular weight with broad distributions of molecular size. Many models have been proposed that use either a Flory type distribution, resulting in a polydispersity of two, or a distribution function to represent the breadth of the distribution. In this work, a model for the distribution of molecular weights is derived as a approximation from a detailed molecular weight model that was previously developed. The model is found to approximate the distribution of molecular weights well for several emulsifier concentrations is continuous stirred tank emulsion polymerization of vinyl acetate. An analysis is also conducted of the transformation of gel permeation chromatography data to weight and number fractional distributions of the molecular sizes.
    Zusätzliches Material: 9 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/app.1989.070371204
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  • 10
    Digitale Medien
    Digitale Medien
    Thermal degradation of polymers. Part XIX. The thermal cyclization and characterization of quinazolone pre-polymers (1978)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 22 (1978), S. 2187-2196 
    Details
    ISSN: 0021-8995
    Schlagwort(e): Chemistry ; Polymer and Materials Science
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Maschinenbau , Physik
    Notizen: A series of pre-polymers prepared from 4,4′-diaminodiphenyl-3,3′dicarboxylic acid and aromatic diacetamido compounds have been thermally cyclized and their structures have been investigated using infrared spectroscopy, combustion analysis, and weight loss techniques. The structures obtained on cyclization are discussed in terms of concurrent cyclization and decarboxylation reactions resulting in incomplete cyclization. Specific structural features due to the lability of main chain bonds at the cyclization temperatures are also discussed. Dynamic thermogravimetry and isothermal weight loss studies have been used to evaluate thermal stability and kinetic parameters. The results are discussed in terms of the overall complexity of the polymer structure and the complexity of the degradation process. It is concluded that in such systems, where the structural variations are large, it is not possible to define a meaningful stability sequence because like systems are not under comparison.
    Zusätzliches Material: 2 Ill.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1002/app.1978.070220811
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