Accueil
Détail de l'auteur
Auteur Qin Shen |
Documents disponibles écrits par cet auteur
Ajouter le résultat dans votre panier Affiner la recherche
Influences of maleic reactive surfactants with different EO chain lengths on the properties of the acrylate latices / Jianhong Yang in JOURNAL OF COATINGS TECHNOLOGY AND RESEARCH, Vol. 12, N° 6 (11/2015)
[article]
Titre : Influences of maleic reactive surfactants with different EO chain lengths on the properties of the acrylate latices Type de document : texte imprimé Auteurs : Jianhong Yang, Auteur ; Yanhong Zhu, Auteur ; Jianfeng Zhu, Auteur ; Wanghui Liu, Auteur ; Ming Zhou, Auteur ; Lingmin Zhi, Auteur ; Dinglong Li, Auteur ; Qin Shen, Auteur Année de publication : 2015 Article en page(s) : p. 1041-1052 Note générale : Bibliogr. Langues : Américain (ame) Catégories : Acrylates Les monomères acrylates sont un groupe d'esters faisant partie des vinyles, car renfermant une double liaison carbone-carbone et sont utilisés pour former des polyacryliques qui ont de multiples usages.
Anhydride maléique
Groupe oxyéthylène
Latex
Polymérisation en émulsion
SurfactantsIndex. décimale : 667.9 Revêtements et enduits Résumé : Three maleic reactive surfactants with different oxyethylene (EO) units (5, 9 and 15) were synthesized and used to prepare the soap-free acrylate latices with methyl methacrylate, butyl acrylate, and hydroxypropyl acrylate as monomers through the polymerization of pre-emulsifying seed emulsion and semi-continuous dropping process. Effects of EO chain lengths on the properties of the latices and their films were investigated. The results showed the polymerization using maleic reactive surfactant with 9 EO units could achieve the highest monomer conversion and the copolymers with highest M w were obtained. The viscosity of latices decreased and their chemical stabilities and particle sizes increased with the increase of EO chain lengths. The EO chain lengths slightly influenced the pencil hardness and adhesion of the latex films, but the shorter the EO chain lengths were, the better were these properties. The amount of maleic reactive surfactants had effects on the properties of the acrylate latices as well. In addition, the results from TEM showed that the latex particles were irregular and there were some “caves” in the particles. It was considered that the particles were formed due to the coil and entanglement of the growing polymer chains in the aqueous phase. Note de contenu : - EXPERIMENTAL : Materials - Preparation of maleic reactive surfactants - Synthesis of soap-free acrylate latex - Characterization
- RESULTS AND DISCUSSION : Preparation of maleic reactive surfactants - Effects of maleic reactive surfactants on emulsion polymerization - H NMR analysis - GPC analysis - Effects of surfactants on particle sizes and their distribution - Stability against electrolyte - Viscosity - Effects of reactive surfactants on mechanical propertiesDOI : 10.1007/s11998-015-9696-x En ligne : https://link.springer.com/content/pdf/10.1007%2Fs11998-015-9696-x.pdf Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=24956
in JOURNAL OF COATINGS TECHNOLOGY AND RESEARCH > Vol. 12, N° 6 (11/2015) . - p. 1041-1052[article]Réservation
Réserver ce document
Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité 17585 - Périodique Bibliothèque principale Documentaires Disponible Preparation in presence of urushiol and properties of acrylate latex with interparticle bridges / Jianhong Yang in JOURNAL OF COATINGS TECHNOLOGY AND RESEARCH, Vol. 15, N° 4 (07/2018)
[article]
Titre : Preparation in presence of urushiol and properties of acrylate latex with interparticle bridges Type de document : texte imprimé Auteurs : Jianhong Yang, Auteur ; Qin Shen, Auteur ; Fengqin Shen, Auteur ; Jun Cai, Auteur ; Wanghui Liu, Auteur ; Ming Zhou, Auteur Année de publication : 2018 Article en page(s) : p. 819-830 Note générale : Bibliogr. Langues : Américain (ame) Catégories : Angle de contact
Caractérisation
Humidité -- Absorption:Eau -- Absorption
Latex
Polyacrylates
Polymérisation en émulsion
Potentiel zeta
Résonance magnétique nucléaire
Revêtements -- Propriétés mécaniques
Revêtements -- Propriétés thermiques
Spectrométrie infrarouge
UrushiolL’urushiol est une toxine organique que l'on trouve dans les plantes de la famille des Anacardiaceae, spécialement dans le genre Toxicodendron (par exemple le sumac grimpant en Amérique du Nord). Il provoque des allergies de la peau ou dermatites, pouvant être importantes, au contact de ces plantes. Le nom vient du mot japonais urushi (漆?), qui désigne une laque produite dans l'Asie orientale à partir du suc des arbres kiurushi (arbre à laque). L'oxydation et la polymérisation de l'urushiol dans le suc de l'arbre en présence d'humidité permet de former une laque dure utilisée traditionnellement pour produire des objets d'art laqués en Chine et au Japon.Index. décimale : 667.9 Revêtements et enduits Résumé : Acrylate latices were prepared by seeded emulsion polymerization of methyl methacrylate (MMA) and butyl acrylate (BA) in presence of urushiol with multifunctional groups (0–6 wt%). The emulsion polymerization was strongly influenced by the urushiol content. With increasing urushiol content, the conversion rate of the monomers first increased then decreased, the stability of emulsion polymerization gradually declined, the average particle size of the latex increased from 115.9 to 175.3 nm, and a change from mono- to bimodal particle size distribution occurred. Interestingly, transmission electron microscopy (TEM) showed that some particles were connected by linear bridges in presence of urushiol. Based on results of 1H nuclear magnetic resonance (NMR) analysis, such formation of interparticle bridges is due to participation of urushiol in the emulsion polymerization of the acrylate monomers. The content of urushiol also affected the properties of latex films. With increasing urushiol content from 0 to 3 wt%, the adhesion, pencil hardness, and contact angle were markedly improved from grade 6 to grade 2, from B to 3H, and from 22° to 61°, respectively, due to formation of interparticle bridges. When the content of urushiol exceeded 3 wt%, the adhesion and pencil hardness remained unchanged, but the water contact angle markedly declined because of higher surface roughness of the latex film. Furthermore, addition of urushiol enhanced the thermal stability of the latex films. Note de contenu : - EXPERIMENTAL : Materials - Preparation of acrylate latex - Preparation of acrylate latex films - Characterization
- RESULTS AND DISCUSSION : IR spectra - H NMR analysis - Average size and zeta potential of latex particles - Conversion and coagulation rate - Contact angle and water absorption - Thermal properties - Mechanical propertiesDOI : 10.1007/s11998-017-0023-6 En ligne : https://link.springer.com/content/pdf/10.1007%2Fs11998-017-0023-6.pdf Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=30859
in JOURNAL OF COATINGS TECHNOLOGY AND RESEARCH > Vol. 15, N° 4 (07/2018) . - p. 819-830[article]Réservation
Réserver ce document
Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité 20078 - Périodique Bibliothèque principale Documentaires Disponible