Dépouillements

UV spot curing facilitates bonding in critical areas / John Beasley in ADHESIVES AGE, Vol. 40, N° 4 (04/1997)  

[article]  inADHESIVES AGE > Vol. 40, N° 4 (04/1997) . - p. 20-21 Titre : UV spot curing facilitates bonding in critical areas Type de document : texte imprimé Auteurs : John Beasley, Auteur Année de publication : 1997 Article en page(s) : p. 20-21 Note générale : Bibliogr. Langues : Américain (ame) Catégories : Adhésifs -- Appareils et matériel Adhésifs -- Séchage sous rayonnement ultraviolet Réticulation (polymérisation) Index. décimale : 668.3 Adhésifs et produits semblables Résumé : Spot curing lamps have been around for about 15 years. The first systems were built by adhesive manufacturers who needed small portable curing systems to process and evaluate their adhesives and coatings. They started out as what would kindly be considered prototyping or demonstration tools that were barely able to cure the adhesives in a reasonable time. At best, the intensity was about 300 mW/[cm.sup.2] from the end of the light guide, and the power quickly dropped off to a fraction of the initial intensity. This meant that if an engineer specified a process with the lamp when new, the process very quickly fell below the minimum requirement, and the potential for producing bonds that were incomplete was very high. At this point, the adhesive manufacturer was not as concerned with perceived process variables that lay with the equipment, but rather with the adhesive variables, as this was where the engineer had the least amount of experience and therefore the greatest amount of anxiety as to how the process was to be verified. To be fair, there were times when the adhesive was the culprit due to improper formulation or lack of care taken in how the adhesives were stored in the customer's facility, but usually the problem lay with the poor performance of the existing spot cure equipment. The difficulty was diagnosing and correcting this equipment problem while still maintaining a working process. One method presented itself when equipment manufacturers began to offer radiometers to determine what intensities were being generated by the low power lamps and to allow the engineer the ability to make a time adjustment to compensate for the unpredictable loss in generated intensity. En ligne : https://drive.google.com/file/d/1se6UOihhXqhGIaYLuuIfXdUFDNQGBXQm/view?usp=drive [...] Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=20387 [article]

Exemplaires (1)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
001074	-	Périodique	Bibliothèque principale	Documentaires	Exclu du prêt

UV curable polyacrylate hot melt polymers for PSAs / Jürgen Barwich in ADHESIVES AGE, Vol. 40, N° 4 (04/1997)  

[article]  inADHESIVES AGE > Vol. 40, N° 4 (04/1997) . - p. 22-24 Titre : UV curable polyacrylate hot melt polymers for PSAs Type de document : texte imprimé Auteurs : Jürgen Barwich, Auteur ; Uwe Düsterwald, Auteur ; Renate Wüstefeld, Auteur ; Bernd Meyer-Roscher, Auteur Année de publication : 1997 Article en page(s) : p. 22-24 Langues : Américain (ame) Catégories : Adhésifs -- Séchage sous rayonnement ultraviolet Adhésifs sensibles à la pression Adhésifs thermofusibles Polyacrylates Polyacryliques Résistance au vieillissement Résistance thermique Réticulation (polymérisation) Index. décimale : 668.3 Adhésifs et produits semblables Résumé : Solvent-based systems, mostly solutions of rubber/resin mixtures, still have a share of nearly half the PSA market, and in the field of tapes almost 70%. There are two main reasons for this dominance: the good cost/benefit ratio of rubber/resin mixtures and the investments in solvent recovery systems that have been made. Disadvantages of solvent-based PSAs are the environmental hazards, high energy processing, lower coating speeds at high coat weights and poor aging resistance. Hot melts, mostly SIS and SBS-block copolymers, now hold a 15% market share in Western Europe. Their main disadvantages are the lack of aging resistance (due to double bonds) and low heat resistance. Aqueous dispersions make up about 38% of the market volume today. Growth has mostly concentrated on paper labels. Problems arise from moisture sensitivity, high processing energy, low coating speeds at high coat weights and insufficient adhesive performance for tapes. Because of the disadvantages of known products and technologies, there is a market for PSAs that meet the following requirement profile: resistance to aging, environmental safety, low-cost processing and good adhesive performance at the higher coat weights needed for adhesive tapes. This list of needs led to the concept of UV crosslinkable acrylic hot melt polymers. En ligne : https://drive.google.com/file/d/1jDtF0VmLdKcglFNIGfb4RYUtk0z5v8xr/view?usp=drive [...] Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=20388 [article]

Exemplaires (1)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
001074	-	Périodique	Bibliothèque principale	Documentaires	Exclu du prêt

Foam-in-place gasketing reduces costs for first-tier auto suppliers in ADHESIVES AGE, Vol. 40, N° 4 (04/1997)  

[article]  inADHESIVES AGE > Vol. 40, N° 4 (04/1997) . - p. 26-27 Titre : Foam-in-place gasketing reduces costs for first-tier auto suppliers Type de document : texte imprimé Année de publication : 1997 Article en page(s) : p. 26-27 Langues : Américain (ame) Catégories : Coût -- Contrôle Ethylène-propylène-diène monomère Joints d'étanchéité Mousses plastiques Thermodurcissables Index. décimale : 668.3 Adhésifs et produits semblables Résumé : A gasketing material is helping first-tier automotive suppliers cut gasketing costs and inventories. Calles Dynafoam, the single-component robotically applied thermoset foam-in-place (FIP) gasket material is replacing hand-applied EPDM gaskets in various applications. Note de contenu : - Door panel modules - Rear light assemblies En ligne : https://drive.google.com/file/d/1SsAC2M7UJbsVfDONC2ffcCa-qnNm_L3Z/view?usp=drive [...] Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=20389 [article]

Exemplaires (1)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
001074	-	Périodique	Bibliothèque principale	Documentaires	Exclu du prêt

Achieving high service temperatures with thermoplastic elastomers / R. Himes in ADHESIVES AGE, Vol. 40, N° 4 (04/1997)  

[article]  inADHESIVES AGE > Vol. 40, N° 4 (04/1997) . - p. 28-32 Titre : Achieving high service temperatures with thermoplastic elastomers Type de document : texte imprimé Auteurs : R. Himes, Auteur ; D. R. Hansen, Auteur ; D. L. Shafer, Auteur ; S. L. Fulton, Auteur Année de publication : 1997 Article en page(s) : p. 28-32 Note générale : Bibliogr. Langues : Américain (ame) Catégories : Adhésifs thermofusibles Copolymère styrène-éthylène-butadiène Copolymères séquencés Elastomères thermoplastiques Ether de polyphénylène Faisceaux électroniques Formulation (Génie chimique) Mastics thermofusibles Matières premières Réticulation (polymérisation) Index. décimale : 668.3 Adhésifs et produits semblables Résumé : Styrenic block copolymers are quite useful in many adhesive applications. They can be processed as hot melts at high line speeds or as high solids solution coatings. The thermoplastic nature of the styrene endblocks allows the reversible transition from rigid, reinforcing "physical crosslinks" to a soft, easy processing polymer. At temperatures below the glass transition ([T.sub.g]) of the styrene domains (approximately 95°C), the copolymers exhibit properties of a reinforced vulcanized elastomer with tensile strengths up to 35 Mpa in the neat form. At temperatures above the polystyrene Tg, the network weakens and flow is possible. Thus, most styrenic block copolymer adhesive formulations are limited to service temperatures of [less than or equal to] 90°C. Improvements to the service temperature of styrenic block copolymers have been made by electron beam or UV crosslinking star type block copolymers (1). However, not every application can utilize this technique. Many applications, such as automotive or construction applications, would benefit from adhesives which can be hot melt or solvent applied but which have upper service temperatures in the 100-150 [degrees] C range. Blending with endblock compatible resins is a potential approach. However, most conventional end-block resins cannot raise the glass transition temperature of the styrene endblocks because they have Tgs around the same value as polystyrene. Polyphenylene ether is one of the few polymers that is compatible with polystyrene (2) and that has a glass transition temperature in the range of 130°C to 214°C depending upon the molecular weight (Table I). Adding polyphenylene ether to styrenic block copolymers has been considered before (3, 4, 5, 6), but it has been difficult to commercially practice because of the high viscosities and because of the required high processing temperatures. A new low molecular weight polyphenylene ether, which may be available soon in developmental quantities, shows great promise for easy incorporation into SEBS (styrene-ethylene/butylene-styrene) adhesive systems to significantly increase the service temperature properties. Note de contenu : - Polyphenylene ether - Materials evaluated - Formulations - Service temperature results - Lower viscosity TPEs - Endblock Reinforcing En ligne : https://drive.google.com/file/d/1Z_7h7jHiKKwek8tw5S8ke7prAnG6Htqy/view?usp=drive [...] Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=20390 [article]

Exemplaires (1)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
001074	-	Périodique	Bibliothèque principale	Documentaires	Exclu du prêt