Titre : |
Relationship of leather break to grain and flesh layers stress - Strain properties |
Type de document : |
texte imprimé |
Auteurs : |
Jorge A. Vergara, Auteur ; Alberto Sofia, Auteur ; José Hidalgo van Dick, Auteur ; Victor D. Vera, Auteur |
Année de publication : |
1979 |
Article en page(s) : |
p. 25-27 |
Note générale : |
Bibliogr. |
Langues : |
Anglais (eng) |
Catégories : |
Emulsions Homopolymères Matériaux -- Imprégnation Polyacrylate d'éthyle Polyacrylate de butyle Polyacrylate de méthyle Polymérisation en émulsion Polyméthacrylate de méthyleLe 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. Rigidité (mécanique) Rupture (mécanique)
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Index. décimale : |
675 Technologie du cuir et de la fourrure |
Résumé : |
Four impregnating resins (homopolymers) were produced from methyl acrylate, ethyl acrylate, butyl acrylate and methyl methacrylate monomers respectively. The emulsion polymerisation method and other chemical agents were maintained constant. Upper leathers were impregnated with these resins following a statistical design which included non-impregnated leathers as controls. Leather break and stiffness were assessed before and after the impregnating process. The elasticity modulus at 2% extension was measured for ail leathers and also in their respective grain and flesh layers after splitting. From the results obtained several concrete facts emerged. First, the leather break and stiffness increased in the following resins order: butyl acrylate < ethyl acrylate= methyl methacrylate < methyl acrylate. Relationships of the grain layer elasticity modulus to the flesh layer one for the impregnated leathers (Mi grain/Mi flesh) and for the control leathers (Mc grain/Mc flesh) were calculated. It was found that an increase in the difference between these two relationships correlated very well with the increase found in the leather break. On the other hand, when the leathers were impregnated with film forming polymers, their elasticity modulus increased proportionally to the polymer hardness increase. |
Note de contenu : |
- EXPERIMENTAL : Impregnating emulsions - Leather ande application of the impregnating resin
- RESULTS : Leather break - Stiffness - Elasticity modulus
- Table 1 : Emulsion composition
- Table 2 : Break (0 = poor ; 10 = escellent) control leather score = 5.0
- Table 3 : Stiffness (0 = soft ; 5 = extremely rigid) (control leather score = 2.0
- Table 4 : Impregnated leather elasticity modulus measured at 2% of strain (g/mm2) (control leather elasticity modulus = 1.444 g/mm2)
- Table 5 : Relative variation of elasticity modulus (ΔMR) of grain and corium layers of impregnated leather referred to the control and break increase obtained with each resin emulsion |
En ligne : |
https://drive.google.com/file/d/1NNJQVVSKaupq3f55T1L04_U_ORQefQ0e/view?usp=drive [...] |
Format de la ressource électronique : |
Pdf |
Permalink : |
https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=34137 |
in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC) > Vol. 63, N° 2 (03-04/1979) . - p. 25-27