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Titre : Cyclic carbonate, not isocyanate : Glycerol sourced from biodiesel may provide an alternative to isocyanate polyurethanes in coating applications Type de document : texte imprimé Auteurs : Andreas Fischer, Auteur Année de publication : 2023 Article en page(s) : p. 22-27 Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Carbonate cyclique
GlycérineLe glycérol, ou glycérine, est un composé chimique de formule HOH2C–CHOH–CH2OH. C'est un liquide incolore, visqueux et inodore au goût sucré, utilisé dans de nombreuses compositions pharmaceutiques. Sa molécule possède trois hydroxyles correspondant à trois fonctions alcool responsables de sa solubilité dans l'eau et de sa nature hygroscopique. Un résidu glycérol constitue l'articulation centrale de tous les lipides de la classe des triglycérides et des phosphoglycérides.
PROPRIETES PHYSIQUES : Le glycérol se présente sous la forme d'un liquide transparent, visqueux, incolore, inodore, faiblement toxique si ingéré (mais laxatif à haute dose), au goût sucré.
Le glycérol peut se dissoudre dans les solvants polaires grâce à ses trois groupes hydroxyles. Il est miscible dans l'eau et l'éthanol ; et insoluble dans le benzène, le chloroforme et le tétrachlorométhane.
Son affinité avec l'eau le rend également hygroscopique, et du glycérol mal conservé (hors dessicateur ou mal fermé) se dilue en absorbant l'humidité de l'air.
- PROPRIETES CHIMIQUES : Dans les organismes vivants, le glycérol est un composant important des glycérides (graisses et huiles) et des phospholipides. Quand le corps utilise les graisses stockées comme source d'énergie, du glycérol et des acides gras sont libérés dans le sang.
- DESHYDRATATION : La déshydratation du glycérol est faite à chaud, en présence d'hydrogénosulfite de potassium (KHSO3) et produit de l'acroléine
- ESTERIFICATION : L'estérification du glycérol conduit à des (mono, di ou tri) glycérides.
- AUTRES PROPRIETES : Le glycérol a un goût sucré de puissance moitié moindre que le saccharose, son pouvoir sucrant est de 0,56-0,64 à poids égal13.
Le glycérol a des propriétés laxatives et diurétiques faibles.
Comme d'autres composés chimiques, tels que le benzène, son indice de réfraction (1,47) est proche de celui du verre commun (~1,50), permettant de rendre "invisibles" des objets en verre qui y seraient plongés.
Isocyanates -- Suppression ou remplacement
Réticulants -- Produits de remplacement
Revêtements (produits chimiques)
Revêtements organiquesIndex. décimale : 667.9 Revêtements et enduits Résumé : Effective methods for the synthesis of two cyclic carbonates based on glycerol have been developed at the institute. They have been successfully converted with amines into a whole range of isocyanate-free polyurethanes, some of which are already suitable for formulating simple coatings. Note de contenu : - NIPUS outperform traditional PUS
- Getting to bio-based cyclic carbonates
- Carbon dioxide : too energy intensive
- Sugarbased carbonates : too expensive ?
- Glycerol : just right !
- Ester carbonates in high purity and yield
- Bio-based isocyanate-free polyurethanes
- Room-temperature-curing systems posible
- Great potential for use in aqueous or emulsified formulation
- Fig. 1 : Traditional PU chemistry compared with NIPU chemistry
- Fig. 2 : (Epoxidised) natural oils and natural oils and sugar alochols as raw materials for cyclic carbonates
- Fig. 3 : Glycerol as a raw material for cyclic carbonates
- Fig. 4 : Infrared spectrum of a multifunctional carbonate
- Fig. 5 : Reactions of cyclic carbonates with amines
- Fig. 6 : Infrared spectrum of ADC (here : AC) and the polymer obtained with IPDA
- Fig. 7 : Molecular weight distribution, determined by GPC, of a polymer made from ADC and HMDA
- Fig. 8 : TDC- and ADC-based NIPU applied to glass plates
- Table 1 : Melting point, purity and yield of the prepared dicarbonates
- Table 2 : MOlecular weights of the polymers measured by GPC under altenative reaction conditionsEn ligne : https://drive.google.com/file/d/1hQKNDeDuwm4e4xfPalUqsB3JeCOx-2zH/view?usp=drive [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=39666
in EUROPEAN COATINGS JOURNAL (ECJ) > (07-08/2023) . - p. 22-27[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 24129 - Périodique Bibliothèque principale Documentaires Disponible Epoxide tannage : a way forward / R. J. Heath in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC), Vol. 89, N° 5 (09-10/2005)
[article]
Titre : Epoxide tannage : a way forward Type de document : texte imprimé Auteurs : R. J. Heath, Auteur ; Y. Dy, Auteur ; S. Clara, Auteur ; A. Hudson, Auteur ; H. Manock, Auteur Année de publication : 2005 Article en page(s) : p. 186-193 Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Epoxydes
Etudes comparatives
Réticulants -- Produits de remplacement
Solutions aqueuses (chimie) -- Stabilité
Tannage organique
Toxicologie cellulaireIndex. décimale : 675.2 Préparation du cuir naturel. Tannage Résumé : An understanding of both the reactive functions of epoxide resins and collagen, suggests that some epoxides could be effectively used in organic tannage systems. Such epoxides may be regarded as alternatives to aldehydic tanning systems, having lower toxicity combined with specific polymerization ability. The commercial and technical potential of epoxides as tanning agents are assessed in this review paper. To this end, an introduction to epoxide chemistry is provided based on the tanning chemist’s viewpoint. The literature survey describes epoxideprotein/collagen addition reaction mechanisms and their kinetics, which in turn are discussed with respect to the potential for future work, where these resins will be utilised in novel tanning technology. The potential risks associated with epoxides and modifications to conventional techniques of tanning, are also discussed. Note de contenu : - EPOXIDE CHEMISTRY : The reactivity of the epoxide group - Commercial liquid epoxide resins - Safety issues related to the use of epoxide resins
- THE ADDITION REACTION OF EPOXY TO COLLAGEN/PROTEIN MATERIALS : Reaction mechanisms - Factors influencing the reaction - The properties of epoxide-treated collagen
- Table 1 : Epoxide stability in aqueous solutions
- Table 2 : Comparison of cytotoxicity of different crosslinkers to L929 CellsEn ligne : https://drive.google.com/file/d/1byXRnTAbtZzAlhBM7X4T1snTPG2HQ0js/view?usp=share [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=39228
in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC) > Vol. 89, N° 5 (09-10/2005) . - p. 186-193[article]Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire A novel non-isocyanate and formaldehyde-free technology for solvent- and waterborne systems / Andreas Hermes in SURFACE COATINGS INTERNATIONAL, Vol. 104.6 (11-12/2021)
[article]
Titre : A novel non-isocyanate and formaldehyde-free technology for solvent- and waterborne systems Type de document : texte imprimé Auteurs : Andreas Hermes, Auteur ; Marcel Meeuwisse, Auteur Année de publication : 2021 Article en page(s) : p. 474-477 Langues : Anglais (eng) Catégories : Formaldéhyde -- Suppression ou remplacement
Isocyanates -- Suppression ou remplacement
Réticulants -- Produits de remplacement
Revêtement en phase solvant
Revêtements en phase aqueuse
Revêtements organiquesIndex. décimale : 667.9 Revêtements et enduits Résumé : The challenges of modern industry are increasingly demanding for paint formulators. Economically, it is necessary to reduce the cost of raw materials to produce excellent quality at lower prices. Technologically, it is necessary to achieve ever increasing performance on the coating system with faster drying times and shorter process cycles. From an environmental point of view, solvent emissions and waste water pollution must be reduced. In terms of health and safety, it is necessary to protect production workers from hazardous substances and to minimise ambient air pollution. allnex's R&D is dedicated to developing sustainable solutions to help formulators meet these challenges.
The wood coatings industry in Europe is divided into two different technology regions and both of them have major challenges to solve. Southern Europe is dominated by 2K polyurethane isocyanate technology, whereas Northern Europe focuses on 2K acid-curing systems. Regarding occupational safety and environmental protection, the emphasis is in both cases on the crosslinking component. European regulations on the labelling of dangerous & hazardous substances have become more restrictive in recent years. European Directive No. 1272/2008 stipulates that formaldehyde at a concentration greater than 0.1% must be labelled as a carcinogen. This also applies to MDI-based isocyanates, which are used on a large scale in Southern Europe. This labelling leads to considerably higher costs, additional protective equipment for production workers, special storage of raw materials and finished products as well as special tare for the transport of the goods to the customer.
Currently there are several new ways to obtain isocyanate- or formaldehyde-free coatings. However, many of these new systems still have limitations in terms of technical performance, choice of substrate or require a modification of the application line, which is associated with additional costs.
The objective of this work is to demonstrate our improvements in the development of safer crosslinkers and coating systems that can be used on conventional equipment. The results presented in this paper are based on simple formulations whose properties have not yet been optimised in terms of flow, rheology, defoaming, deaeration, etc. This adjustment is the responsibility of the formulators and must be determined individually for each application.
This work was carried out as part of the allnex ECOWISETM sustainable program, in which special emphasis is placed on 'green' technologies. Examples include the use of renewable raw materials, the reduction of wastewater pollution and the reduction of emissions of all kinds.Note de contenu : - Solution 1 for solventborne coatings based on acrylate/isocyanate
- Solution 2 for solventborne coatings based on alkyd/urea-formaldehyde systemsEn ligne : https://drive.google.com/file/d/17ZfScbC7b-viuFRspRikz2MLj0Zxw0CJ/view?usp=drive [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=36647
in SURFACE COATINGS INTERNATIONAL > Vol. 104.6 (11-12/2021) . - p. 474-477[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 23079 - Périodique Bibliothèque principale Documentaires Disponible Replacing methylenedianiline with a new blend in advanced composites / Yong Tang in JEC COMPOSITES MAGAZINE, N° 132 (01-02/2020)
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Titre : Replacing methylenedianiline with a new blend in advanced composites Type de document : texte imprimé Auteurs : Yong Tang, Auteur ; Shannon Taylor, Auteur ; Paul Wiggins, Auteur Année de publication : 2020 Article en page(s) : p. 56-58 Langues : Anglais (eng) Catégories : Composites à fibres de carbone -- Moulage par injection
Composites à fibres de carbone -- Propriétés mécaniques
DiaminodiphénylméthaneLe 4,4'-diaminodiphénylméthane est une amine aromatique de formule brute C13H14N2 considérée comme dangereuse pour la santé et retirée progressivement du marché européen à partir du 17 février 2011.
Le 4,4'-diaminodiphénylméthane est obtenu via une réaction de condensation du formaldéhyde avec l'aniline en présence d'acide chlorhydrique. (Wikipedia)
Durée de vie (Ingénierie)
Epoxydes
Etudes comparatives
Réticulants -- Produits de remplacement
Stratifiés
Transition vitreuseIndex. décimale : 668.4 Plastiques, vinyles Résumé : 4,4'-methylenedianiline (MDS) was widely used as hardener for epoxy resins but, due to recent regulations, people are attempting to fine viable alternatives to MDS. In a study conducted by Albemarle Corporation, MDA and E100 were used as curing agents for EPON 826. The study demonstrated that the tensile and flexural properties developed from E300 are slightly better than those of DDS and the amount of water absorbed by the E300-cured system is considerably less than that of commonly used DDS, indicating improved resistance to the harmful degradation effect of absorbed water. Note de contenu : - Fig. 1 : Working life comparison between MDA and E100
- Fig. 2 : Tg development of cure temperature and time
- Fig. 3 : E270 sample and get time at different temperature
- Fig. 4 : Injection moulding process to make laminates with housed N2
- Table 1 : Properties of E100 and MDA-cured systems
- Table 2 : Properties of MY729 epoxy resin cured with E300 and DDSEn ligne : https://drive.google.com/file/d/1nBM4YaNj1gWXqK34fRrgSq8Hmk8lq8mz/view?usp=drive [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=33904
in JEC COMPOSITES MAGAZINE > N° 132 (01-02/2020) . - p. 56-58[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 21395 - Périodique Bibliothèque principale Documentaires Disponible A safer alternative takes the pressure out of formulating pressure-sensitive adhesives / Hitesh Soni in ADHESIVES & SEALANTS INDUSTRY (ASI), Vol. 23, N° 3 (03/2016)
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Titre : A safer alternative takes the pressure out of formulating pressure-sensitive adhesives : A new, tetrafunctional epoxy reactive modifier is increasingly being used as non-mutagenic, drop-in formulation replacement for polyfunctional aziridine Type de document : texte imprimé Auteurs : Hitesh Soni, Auteur Année de publication : 2016 Langues : Américain (ame) Catégories : Adhésifs en phase aqueuse
Adhésifs sensibles à la pression
Epoxydes
Formulation (Génie chimique)
Méta-xylènediamine
Polyacryliques
Réticulants -- Produits de remplacementIndex. décimale : 668.3 Adhésifs et produits semblables Résumé : Testing for key performance properties for PSAs illustrate that the new epoxy reactive modifier, a tetrafunctional glycidyl diamine, is a highly effective and efficient crosslinker in waterborne, acrylic formulations to decrease peel adhesion, increase shear strength and eliminate any problems with adhesive transfer to substrates by increasing the cohesive strength of the treated adhesives. The epoxy reactive modifier demonstrates equivalent performance to the polyfunctional aziridine crosslinker tested in terms of shear adhesion and increased cohesive strength. While the decrease in peel adhesion with the epoxy reactive modifier is not as extensive as with the aziridine crosslinker tested, the epoxy reactive modifier exhibits a good balance of performance properties and does create substantial and entirely acceptable reductions in peel adhesion in PSAs.
In addition to enhancing performance of PSAs, the epoxy reactive modifier also offers benefits that the polyfunctional aziridine crosslinker does not, such as manufacturing efficiency and a safer HS&E profile, making it an attractive alternative. For example, while the tetrafunctional glycidyl diamine will remain active in formulated adhesives for several days, systems treated with other crosslinkers have a short pot life and will require re-inoculation of the adhesive due to decomposition of the aziridine due to hydrolysis. In addition, the tetrafunctional glycidyl diamine does not carry with it the types of safety and health concerns that are inherent in the aziridine systems. As a result, it is a safer, more efficient choice for adhesives formulators looking to replace potentially mutagenic polyfunctional aziridine crosslinkers with an easy drop-in replacement.En ligne : http://www.adhesivesmag.com/articles/94480-a-safer-alternative-takes-the-pressur [...] Format de la ressource électronique : Web Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=26020
in ADHESIVES & SEALANTS INDUSTRY (ASI) > Vol. 23, N° 3 (03/2016)[article]Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire