Coagent modified polypropylene prepared by reactive extrusion : a new look into the structure-property relations of injection molded parts / P. Tiwary in INTERNATIONAL POLYMER PROCESSING, Vol. XXXI, N° 4 (08/2016)  

[article]  inINTERNATIONAL POLYMER PROCESSING > Vol. XXXI, N° 4 (08/2016) . - p. 433-441 Titre : Coagent modified polypropylene prepared by reactive extrusion : a new look into the structure-property relations of injection molded parts Type de document : texte imprimé Auteurs : P. Tiwary, Auteur ; H. Gui, Auteur ; P. L. Ferreira, Auteur ; Marianna Kontopoulou, Auteur Année de publication : 2016 Article en page(s) : p. 433-441 Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Essais dynamiques Extrusion réactive Matières plastiques -- Moulage par injection Matières plastiques -- Propriétés mécaniques Matières plastiques -- Propriétés thermiques Polypropylène Rhéologie Trimésate de triallyle Triméthylolpropane Index. décimale : 668.4 Plastiques, vinyles Résumé : Peroxide-mediated reactive extrusion of linear isotactic polypropylene (L-PP) was conducted in the presence of trimethylolpropane trimethacrylate (TMPTMA) and triallyl trimesate (TAM) coagents, using a twin screw extruder. The resulting coagent-modified polypropylenes (CM-PP) had higher viscosities and elasticities, as well as increased crystallization temperature compared to PP reacted only with peroxide (DCP-PP). Additionally, deviations from terminal flow, and strain hardening were observed in PP modified with TAM, signifying the presence of long chain branching (LCB). The CM-PP formulations retained the modulus and tensile strength of the parent L-PP, in spite of their lower molar mass and viscosities, whereas their elongation at break and the impact strength were better. This was attributed to the finer spherulitic structure of these materials, and to the disappearance of the skin-core layer in the injection molded specimens. Note de contenu : - EXPERIMENTAL : Materials - Reactive extrusion - Gel content analysis and gel permeation chromatography (GPC) - Injection molding - Mechanical testing - Optical microscopy - Differential scanning calorimetry (DSC) - RESULTS AND DISCUSSION : Rheological characterization - Thermal properties and crystalline structure of the skin and core layers - Mechanical properties DOI : 10.3139/217.3209 En ligne : https://drive.google.com/file/d/1tmHvxYaYmC_e0sd04Cwff5dRoA6Ky-Cb/view?usp=drive [...] Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=26805 [article]

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Stretch-blow molding of PET copolymers - influence of molecular architecture / E. Déloye in INTERNATIONAL POLYMER PROCESSING, Vol. XXVII, N° 3 (07/2012)  

[article]  inINTERNATIONAL POLYMER PROCESSING > Vol. XXVII, N° 3 (07/2012) . - p. 358-369 Titre : Stretch-blow molding of PET copolymers - influence of molecular architecture Type de document : texte imprimé Auteurs : E. Déloye, Auteur ; Jean-Marc Haudin, Auteur ; N. Billon, Auteur Année de publication : 2012 Article en page(s) : p. 358-369 Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Acide isophthalique 'acide isophtalique ou l'acide benzène-1,3-dicarboxylique, est un acide dicarboxylique aromatique de formule C6H4(COOH)2. C’est un isomère de l’acide téréphtalique et de l’acide phtalique. Masse moléculaire : 166,1 g/mol. Diéthylène glycol Matières plastiques -- Moulage par soufflage Polyéthylène téréphtalate Structure moléculaire Triméthylolpropane Index. décimale : 668.4 Plastiques, vinyles Résumé : The purpose of the paper is to study the influence of molecular architecture of poly(ethylene terephthalate) (PET) on its ability to be processed by stretch-blow molding, which is not well documented in the literature. To evaluate this process ability, it proposes an original strategy combining laboratory analyses and experiments on a prototype machine. PET copolymers were prepared from three types of comonomers: diethylene glycol (DEG), isophthalic acid (IPA) and trimethylolpropane (TMP). It is first shown, through laboratory experiments, that the nature of the polymer in terms of chain constitution (copolymerization), chain length (intrinsic viscosity) and purity (catalytic residues) greatly affects many properties: melt crystallization, thermal properties, polymer rigidity and drawability. These different properties obviously induce very different behaviours at the different steps of the stretch-blow molding process: injection-molding of the preform (quenchability), heating (IR absorption), stretch-blow (rigidity and drawability). The stretch-blow step has been simulated on a prototype apparatus designed in our laboratory. It has been shown that free blowing can be used to characterize the process ability of the polymer. A statistical analysis has confirmed the great differences between the materials investigated and pointed out the complexity of the material response during blowing. DOI : 10.3139/217.2549 En ligne : https://drive.google.com/file/d/1Wnc9qot-nbTluYL9Wg2gFqk4-U1WD1FG/view?usp=drive [...] Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=15582 [article]

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Syntheses and characterizations of two-component polyurethane flame retardant coatings using 2,4-dichloro modified polyesters / Chang-Hwan Park in JOURNAL OF COATINGS TECHNOLOGY (JCT), Vol. 69, N° 875 (12/1997)

[article]  inJOURNAL OF COATINGS TECHNOLOGY (JCT) > Vol. 69, N° 875 (12/1997) . - p. 41-47 Titre : Syntheses and characterizations of two-component polyurethane flame retardant coatings using 2,4-dichloro modified polyesters Type de document : texte imprimé Auteurs : Chang-Hwan Park, Auteur ; Jong-Pyo Wu, Auteur ; Hong-Soo Park, Auteur ; Seong-Kil Kim, Auteur Année de publication : 1997 Article en page(s) : p. 41-47 Note générale : Bibliogr. Langues : Américain (ame) Catégories : Couches minces Dichlorobenzoïque, Acide Durée de vie en pot Esterification Ignifugeants Composé chimique utilisé pour réduire l'inflammabilité. Il peut être incorporé au produit durant sa fabrication ou appliqué ultérieurement à sa surface. Polycondensation Polyester chloré Polyesters Polyisocyanates Polyuréthanes Revêtement -- Séchage Revêtements bi-composant Triméthylolpropane Index. décimale : 667.9 Revêtements et enduits Résumé : Polyurethane flame retardant coatings are composed of polyols and polyisocyanates. Flame retardant groups are usually introduced to the polyol structure. In this research intermediates were obtained by esterification of 2,4-dichlorobenzoic acid and trimethylolpropane for the purpose of introducing a flame retardant group to the polyol structure. Then chlorine-containing modified polyesters were synthesized by polycondensation of trimethylolpropane, adipic acid, 1,4-butanediol, and the intermediate. The content of 2,4-dichlorobenzoic acid in the intermediate was varied with 10, 20, and 30 wt%. Two-component polyurethane flame retardant coatings were prepared by blending the products with polyisocyanate. Various physical properties of these new flame retardant coatings were comparable to non-flame retardant coatings. They showed drying times of four to seven hours and pot life times of 14-20 hr, which could belong to the flame retardant coatings with long pot life time. The coating with 30 wt% 2,4-dichlorobenzoic acid showed a self-extinguishing property in the vertical burning test. Note de contenu : - EXPERIMENTAL : Materials - Syntheses of 2,4-dichloro modified polyesters - Chlorine contents and kinematic viscosity - Instrumental analyses - Preparation of two-component polyurethane flame retardant coatings - Tests of General properties for flame retardant coatings - Flame retardancy tests - RESULTS AND DISCUSSION : Indentification of 2,4-dichloro modified polyesters - Effects of DCBA content on the kinematic viscosity of modified polyesters - Thermal properties of 2,4-dichloro modified polyesters - Physical properties of flame retardant coatings - Flame retardancy of coatings Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=18068 [article]

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Synthesis and application of highly branched polymers as filling-retanning agents / Chai Yuye in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC), Vol. 94, N° 5 (09-10/2010)  

[article]  inJOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC) > Vol. 94, N° 5 (09-10/2010) . - p. 200-204 Titre : Synthesis and application of highly branched polymers as filling-retanning agents Type de document : texte imprimé Auteurs : Chai Yuye, Auteur ; Wan Xiangxiang, Auteur ; Lan Yunjun, Auteur ; Zhang Shuffen, Auteur Année de publication : 2010 Article en page(s) : p. 200-204 Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Analyse thermique Cuirs et peaux Cuirs et peaux -- Propriétés mécaniques Cuirs et peaux -- Propriétés organoleptiques Cuirs et peaux de porcs Etanchéité Polyaddition Polymères ramifiés Polyméthacrylate de méthyle Le poly(méthacrylate de méthyle) (souvent abrégé en PMMA, de l'anglais Poly(methyl methacrylate)) est un polymère thermoplastique transparent obtenu par polyaddition dont le monomère est le méthacrylate de méthyle (MMA). Ce polymère est plus connu sous son premier nom commercial de Plexiglas (nom déposé), même si le leader global du PMMA est Altuglas International9 du groupe Arkema, sous le nom commercial Altuglas. Il est également vendu sous les noms commerciaux Lucite, Crystalite, Perspex ou Nudec. Retannage Transition vitreuse Triméthylolpropane Index. décimale : 675.2 Préparation du cuir naturel. Tannage Résumé : Highly branched polymers (HBPs) were prepared via free-radical polymerization of methacrylic acid (MAA) with polyfunctional allyl co-monomer (mono-trimethylolpropan trimaleate, PTPTM) at various n(MAA)/n(MTPTM) ratios. HBPs were employed in retanning wet-blue pigskins and the retanned leathers were evaluated by their physical properties such as tensile strength, tear strength, extension at break and organoleptic properties including softness, fullness, smoothness and tightness. The results showed that HBPs did well in filling and retanning leather and especially in the case of n(MAA)/n(MTPTM) = 12:1 (HBP-4). HBP-4 was characterized by HNMR, SEC, DSC and TGA, the results indcated that the polymer showed polydispersity (PDI = 1.456, Mw 27,024, Mn 15 566), its TG/DTG curves showed two-stage decomposition with two weight loss temperature maxima (206.38°C and 429.57°C), the single glass transition on the DSC curve and the Tg (209.98°C) which was lower than that of poly-methacrylic acid (227.85°C) implies that HBP-4 molecules have better flexibility than PMMA and there is no phase separation in the polymer. En ligne : https://drive.google.com/file/d/1yL2dJ49t1nelQb-UDh_jiL8nNWXRQk_r/view?usp=drive [...] Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=9999 [article]

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Synthesis of trimethylolpropane esters of tall oil fatty acids and properties of polyurethane coatings on their basis / Vladimir Yakushin in JOURNAL OF COATINGS TECHNOLOGY AND RESEARCH, Vol. 13, N° 2 (03/2016)  

[article]  inJOURNAL OF COATINGS TECHNOLOGY AND RESEARCH > Vol. 13, N° 2 (03/2016) . - p. 317-324 Titre : Synthesis of trimethylolpropane esters of tall oil fatty acids and properties of polyurethane coatings on their basis Type de document : texte imprimé Auteurs : Vladimir Yakushin, Auteur ; Maria Misane, Auteur ; Oskars Bikovens, Auteur ; Dzintra Vilsone, Auteur ; Irina Sevastyanova, Auteur Année de publication : 2016 Article en page(s) : p. 317-324 Note générale : Bibliogr. Langues : Américain (ame) Catégories : Acides gras Esters Polyols Polyuréthanes Revêtements -- Propriétés mécaniques:Peinture -- Propriétés mécaniques Revêtements:Peinture Triméthylolpropane Index. décimale : 667.9 Revêtements et enduits Résumé : Tall oil fatty acids (TOFA) were esterified with trimethylolpropane (TMP) without a catalyst at different molar ratios of TMP to TOFA. A molar ratio was defined, at which a polyol stable in long-term storage, with the maximum content of TMP monoesters, was synthesized. Fourier transform infrared spectroscopy and gas chromatography were used for the identification of the polyols’ chemical structure and composition. Based on the synthesized polyols, polyurethane coatings were prepared. The effect of the isocyanate index and concentration of traditional Sn-based and less toxic Bi-based catalysts on the gel time of the polyurethane composition, and the mechanical and thermal properties of the coatings was studied. It was found that the new coatings had high tensile strength and modulus of elasticity, comparable with the strength and modulus of the polyurethane based on diethanolamides of TOFA. The initial temperature of decomposition of these coatings was higher than that of the polyurethanes based on esters of TOFA and a number of uralkyds. The coatings based on TMP esters of TOFA were obtained without the use of solvents, and potentially, these esters can be used in spray-applied VOC-free polyurethane coatings’ formulation. Note de contenu : - EXPERIMENTAL : Materials - Synthesis of polyols - Polyol analysis - Preparation and characterization of polyurethane coatings - RESULTS AND DISCUSSION : Properties of polyols - Properties of polyurethanes DOI : 10.1007/s11998-015-9747-3 En ligne : https://link.springer.com/content/pdf/10.1007%2Fs11998-015-9747-3.pdf Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=26116 [article]

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Understanding the role of alkyd composition in anticorrosive coatings / Priyanka Dutta in PAINTINDIA, Vol. LXV, N° 6 (06/2015)  

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