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Dégradation microbienne des polymères de cellulose dans les produits cosmétiques et de toilette / L. A. Harrison in INTERNATIONAL JOURNAL OF COSMETIC SCIENCE, Vol. 9, N° 2 (04/1987)
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Titre : Dégradation microbienne des polymères de cellulose dans les produits cosmétiques et de toilette Type de document : texte imprimé Auteurs : L. A. Harrison, Auteur Année de publication : 1987 Article en page(s) : p. 73-84 Note générale : Bibliogr. Langues : Anglais (eng) Tags : Cellulose polymers Microbial Biodeterioration Enzyme degradation Aspergillus Fusarium Penicillium Index. décimale : 668.5 Parfums et cosmétiques Résumé : Les polymères de cellulose que l'on trouve couramment dans les produits cosmétiques, peuvent servir de cibles potentielles pour les attaques microbiennes et peuvent quelquefois subir une croissance considérable s'ils se trouvent dans des conditions favorables. Comme résultat, les substances cellulosiques peuvent passer d'un gel dur à un liquide "filant", rendant ainsi le produit cosmétique inutilisable.
Afin de mieux comprendre la biodétérioration de la cellulose dans les cosmétiques, cet article passe en revue la structure de la cellulose, les mécanismes de la dégradation des enzymes et les effets des propriétés structurelles de la cellulose au moyen de l'hydrolyse. Au moins trois différents types d'enzymes (exo-B-1,4-glucanase, endo-B-1,4-glucanase et B-glucosidase) sont concernés dans la dégradation de la cellulose cristalline. La production d'enzymes par trois fungi appartenant à la catégorie Aspergillus, Fusarium et Penicillium est décrite.DOI : 10.1111/j.1467-2494.1987.tb00464.x En ligne : https://onlinelibrary.wiley.com/doi/10.1111/j.1467-2494.1987.tb00464.x Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=5237
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Code-barres Cote Support Localisation Section Disponibilité 003927 - Périodique Bibliothèque principale Documentaires Disponible Acid etch of automotive clearcoats. II. Comparison of degradation chemistry in laboratory and field testing / P. J. Schmitz in JOURNAL OF COATINGS TECHNOLOGY (JCT), Vol. 72, N° 902 (03/2000)
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Titre : Acid etch of automotive clearcoats. II. Comparison of degradation chemistry in laboratory and field testing Type de document : texte imprimé Auteurs : P. J. Schmitz, Auteur ; Joseph W. Holubka, Auteur ; Li - Feng Xu, Auteur Année de publication : 2000 Article en page(s) : p. 53-61 Note générale : Bibliogr. Langues : Américain (ame) Tags : Matériau revêtement Vernis Automobile Dégradation chimique Exposition intempérie Retombée atmosphérique Pluie acide Essai laboratoire en champ Etude comparative expérimentale Spectrométrie photoélectron Rayon X Index. décimale : 667.9 Revêtements et enduits Résumé : A laboratory test procedure was developed to quantitatively evaluate the acid etch resistance of automotive clearcoats, Here we attempt to verify that the conditions used in the laboratory test reproduce the field degradation chemistry to assure that the test is evaluating realistic performance characteristics. In this study we applied X-ray photoelectron spectroscopy (XPS) as a tool to determine if degradation products are observable which can be used to verify the consistency of the field and laboratory degradation processes for acrylic melamine-based clearcoats. Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=5822
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Code-barres Cote Support Localisation Section Disponibilité 001207 - Périodique Bibliothèque principale Documentaires Disponible Detrended fluctuation analysis of UV degradation in a polyurethane coating / Mark A. Johnson in JOURNAL OF COATINGS TECHNOLOGY (JCT), Vol. 75, N° 941 (06/2003)
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Titre : Detrended fluctuation analysis of UV degradation in a polyurethane coating Type de document : texte imprimé Auteurs : Mark A. Johnson, Auteur ; Paul J. Cote, Auteur Année de publication : 2003 Article en page(s) : p. 51-57 Note générale : Bibliogr. Langues : Américain (ame) Tags : Propriété surface Méthode analyse Rugosité Feuil Rayonnement UV Analyse Peinture Dégradation photochimique Polyuréthane Index. décimale : 667.9 Revêtements et enduits Résumé : Changes in the intrinsic structure of paint surfaces resulting from extended UV exposure can significantly alter the appearance of paint due to a breakdown in the resin that binds the pigments and flattening agents. In this study, the coating structure of a solvent-based polyurethane was analyzed to establish correlations between the intrinsic spatial scaling properties of the coating and UV exposure time. Atomic force microscopy and laser scanning confocal microscopy were employed to map surface structures over a range of scales from 80 nm to 80 mm. The roughness of the polyurethane surface was characterized in terms of scaling exponents using detrended fluctuation analysis to identify long-range, power law relations, and to correct for inhomogeneities in the surface structure. The time-dependence of the roughening process was also determined and correlated with changes in gloss. Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=5581
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Code-barres Cote Support Localisation Section Disponibilité 000566 - Périodique Bibliothèque principale Documentaires Disponible Hydrothermal degradation study of phenolic polymer coatings by advanced analytical methods / T. Sugama in JOURNAL OF COATINGS TECHNOLOGY (JCT), Vol. 73, N° 917 (06/2001)
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Titre : Hydrothermal degradation study of phenolic polymer coatings by advanced analytical methods Type de document : texte imprimé Auteurs : T. Sugama, Auteur ; S. S. Kelley, Auteur ; K. Gawlik, Auteur Année de publication : 2001 Article en page(s) : p. 65-71 Note générale : Bibliogr. Langues : Américain (ame) Tags : Matériau revêtement Peinture anticorrosion Dégradation chimique Feuil Condition hydrothermale Phénoplaste Oxydation Acier Réaction interface Etude expérimentale Index. décimale : 667.9 Revêtements et enduits Résumé : Resole-type phenolic polymer coatings were deposited on carbon steel panels, and then were exposed for 15 days to a simulated geothermal brine with pH 1.6 at 150°, 175°, and 200°C. The phenolic polymers were hydrothermally oxidized. To comprehensively understand the mechanisms of this oxidative degradation of the coatings, the modern analytical techniques of XPS, contact angle, TGA, SEM-EDX, and EIS were used in combination. The oxidative degradation of polymer took place in the three-step oxidation routes: first, the bridging methylen linkages in the network polymer structure were replaced by the benzylhydrol-type linkages ; second,the benzylhydrol-type linkages were transformed into the benzophenone-type linkages ; and finally, the C-C-C linkage in the benzophenone derivative ruptured to form salicylic acid derivative as the ultimate degradation products. Hydrothermal temperatures of >175°C promoted the degree of such oxidation degradation, causing the coating surface to become susceptible to moisture, to absorb more brine, and also to allow corrosive electrolytes to permeate easily. Consequently, iron oxides as the corrosion products from the underlying steel were yielded at a critical interfacial zone between the coat. The excessive growth of iron oxides led to the generation of internal stress-induced cracks in the coating film, thereby resulting in the failure of these corrosion-preventing barriers. Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=5735
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Code-barres Cote Support Localisation Section Disponibilité 001225 - Périodique Bibliothèque principale Documentaires Disponible Mechanical property changes and degradation during accelerated weathering of polyester-urethane coatings / allen Skaja in JOURNAL OF COATINGS TECHNOLOGY AND RESEARCH, Vol. 3, N° 1 (01/2006)
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Titre : Mechanical property changes and degradation during accelerated weathering of polyester-urethane coatings Type de document : texte imprimé Auteurs : allen Skaja, Auteur ; Dilhan Fernando, Auteur ; Stuart G. Croll, Auteur Année de publication : 2006 Article en page(s) : p. 41-51 Note générale : bibliogr. Langues : Américain (ame) Tags : Vieillissement physique Propriété mécanique chimique Structure moléculaire Etude expérimentale Durabilité Uréthanne polymère produit Résistance intempérie Dégradation photochimique Mécanisme réaction Relaxation structurale Densité réticulation Matériau revêtement Esteruréthanne accéléré Temps exposition Module élasticité Index. décimale : 667.9 Revêtements et enduits Résumé : Chemical changes, measured using spectroscopy, and crosslink density, measured by mechanical thermal analysis, were determined during accelerated weathering on a model polyester-urethane coating of known composition. The tensile modulus, measured above the glass transition temperature, and thus the crosslink density, decreased with exposure, as expected from the chemical changes. However, the tensile modulus, measured at room temperature, increased with exposure. Physical aging of the polymer network was found to occur concurrently with photodegradation and accounts for much of the increase in room temperature modulus. Increased hydrogen bonding in the increasingly oxidized polyester-urethane may also contribute to the increase in modulus at room temperature. Both physical and chemical changes must be determined if changes, and rates of change, in performance due to weathering are to be understood. DOI : 10.1007/s11998-006-0004-7 En ligne : https://link.springer.com/content/pdf/10.1007%2Fs11998-006-0004-7.pdf Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=3711
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Code-barres Cote Support Localisation Section Disponibilité 003762 - Périodique Bibliothèque principale Documentaires Disponible On the use of the atomic force microscope to monitor physical degradation of polymeric coating surfaces / Mark R. VanLandingham in JOURNAL OF COATINGS TECHNOLOGY (JCT), Vol. 73, N° 923 (12/2001)
PermalinkRelating laboratory and outdoor exposure of coatings : IV. Mode and mechanism for hydrolytic degradation / Tinh Nguyen in JOURNAL OF COATINGS TECHNOLOGY (JCT), Vol. 75, N° 941 (06/2003)
PermalinkAnticipating paint cracking / Mark E. Nichols in JOURNAL OF COATINGS TECHNOLOGY (JCT), Vol. 74, N° 924 (01/2002)
PermalinkControlled release of dehydroacetic acid sodium salt for the stability improvement of cosmetic formulations / A. Gazzaniga in INTERNATIONAL JOURNAL OF COSMETIC SCIENCE, Vol. 16, N° 3 (06/1994)
PermalinkEnvironmental fate and effects of dimethicone and cyclotetrasiloxane from personal care applications / C. Stevens in INTERNATIONAL JOURNAL OF COSMETIC SCIENCE, Vol. 20, N° 5 (10/1998)
PermalinkPermalinkMicrostructure and morphology of amine-cured epoxy coatings before and after outdoor exposures - an AFM study / Xiaohong Gu in JOURNAL OF COATINGS TECHNOLOGY AND RESEARCH, Vol. 2, N° 7 (07/2005)
PermalinkMonte Carlo approach to estimating the photodegradation of polymer coatings / Brian R. Hinderliter in JOURNAL OF COATINGS TECHNOLOGY AND RESEARCH, Vol. 2, N° 6 (04/2005)
PermalinkPatterns of erosion from acrylic and fluoropolymer coatings in accelerated and natural weathering tests / Kurt A. Wood in JOURNAL OF COATINGS TECHNOLOGY (JCT), Vol. 74, N° 924 (01/2002)
PermalinkQuantitative spectroscopy to determine the effects of photodegradation on a model polyester - urethane coating / S. G. Scroll in JOURNAL OF COATINGS TECHNOLOGY (JCT), Vol. 75, N° 945 (10/2003)
PermalinkUse of laser scanning confocal microscopy for characterizing changes in film thickness and local surface morphology of UV-exposed polymer coatings / Li-Piin Sung in JOURNAL OF COATINGS TECHNOLOGY AND RESEARCH, Vol. 1, N° 4 (10/2004)
PermalinkUse of reactable light stabilizers to prevent migration and to improve durability of coatings On plastic substrates / Nancy Cliff in JOURNAL OF COATINGS TECHNOLOGY AND RESEARCH, Vol. 2, N° 5 (01/2005)
PermalinkChemical depth profiling of automotive coating systems using slab microtome sectioning with IR/UV-VIS spectroscopy and optical microscopy / Karlis Adamsons in JOURNAL OF COATINGS TECHNOLOGY (JCT), Vol. 74, N° 924 (01/2002)
PermalinkColorant-induced exterior discoloration of latex paints / Lakshmi Sadasivan in JOURNAL OF COATINGS TECHNOLOGY (JCT), Vol. 73, N° 920 (09/2001)
PermalinkComputer analysis of a polymer coating exposed to field weather conditions / Doug Burch in JOURNAL OF COATINGS TECHNOLOGY (JCT), Vol. 74, N° 924 (01/2002)
PermalinkDoes wax protect from acid precipitation / Ulrich Schulz in EUROPEAN COATINGS JOURNAL (ECJ), N° 9/97 (09/1997)
PermalinkDurability of a drag reducing solution / V. Mik in APPLIED RHEOLOGY, Vol. 18, N° 1 (2008)
PermalinkLong-term weathering behavior of UV-curable clearcoats : Depth profiling of photooxidation, UVA, and HALS distributions / Christopher M. Seubert in JOURNAL OF COATINGS TECHNOLOGY AND RESEARCH, Vol. 2, N° 7 (07/2005)
PermalinkMeasurement of mar resistance and study of marring mechanism of polymeric coatings with scanning probe microscope / Weidian C. Shen in JOURNAL OF COATINGS TECHNOLOGY (JCT), Vol. 72, N° 907 (08/2000)
PermalinkMechanism for environmental etch of acrylic melamine - based automotive clearcoats : identification of degredation / P. J. Schmitz in JOURNAL OF COATINGS TECHNOLOGY (JCT), Vol. 72, N° 904 (05/2000)
PermalinkPlastiques. Evaluation de l'action des micro-organismes / Association Française de Normalisation (Paris) / Saint-Denis La Plaine : Association Française de Normalisation (AFNOR) (1997)
PermalinkRelating gloss loss to topographical features of a PVDF coating / Jenny Faucheu in JOURNAL OF COATINGS TECHNOLOGY AND RESEARCH, Vol. 3, N° 1 (01/2006)
PermalinkRelating laboratory and outdoor exposure of coatings : II. Effects of relative humidity on photodegradation and the apparent quantum yield of acrylic - melamine coatings / Tinh Nguyen in JOURNAL OF COATINGS TECHNOLOGY (JCT), Vol. 74, N° 932 (09/2002)
PermalinkRestoration of severely weathered wood / R. Sam Williams in JOURNAL OF COATINGS TECHNOLOGY (JCT), Vol. 72, N° 902 (03/2000)
PermalinkScratch durability of automotive clear coatings : A quantitative, reliable and robust methodology / Vincent Jardret in JOURNAL OF COATINGS TECHNOLOGY (JCT), Vol. 72, N° 907 (08/2000)
PermalinkStructure control, coating properties, and durability of fluorinated acrylic - based polymers / Valter Castelvetro in JOURNAL OF COATINGS TECHNOLOGY (JCT), Vol. 74, N° 928 (05/2002)
PermalinkStructure/property relationships in flexible alkoxysilane automotive coatings / Phillip V. Yaneff in JOURNAL OF COATINGS TECHNOLOGY (JCT), Vol. 74, N° 933 (10/2002)
PermalinkUnexpected electronic effects on benzotriazole UV absorber photostability / Joseph C. Suhadolnik in JOURNAL OF COATINGS TECHNOLOGY (JCT), Vol. 74, N° 924 (01/2002)
PermalinkValidation of the reciprocity law for coating photodegradation / Joannie W. Chin in JOURNAL OF COATINGS TECHNOLOGY AND RESEARCH, Vol. 2, N° 7 (07/2005)
PermalinkWeathering performance of thermoset and photoset acrylate coatings / C. Decker in JOURNAL OF COATINGS TECHNOLOGY (JCT), Vol. 74, N° 924 (01/2002)
PermalinkWood properties affecting finish service life / R. Sam Williams in JOURNAL OF COATINGS TECHNOLOGY (JCT), Vol. 72, N° 902 (03/2000)
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