Accueil
Catégories
> Glutaraldéhyde
GlutaraldéhydeVoir aussi
|
Ajouter le résultat dans votre panier Affiner la recherche
Etendre la recherche sur niveau(x) vers le bas
Synthesis and characterization of chitosan & amino acid superabsorbent hydrogels / Didem Omay in INTERNATIONAL POLYMER PROCESSING, Vol. XXIX, N° 2 (05/2014)
[article]
Titre : Synthesis and characterization of chitosan & amino acid superabsorbent hydrogels Type de document : texte imprimé Auteurs : Didem Omay, Auteur Année de publication : 2014 Article en page(s) : p. 287-294 Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Absorbants et adsorbants
Acides aminésLes acides aminés (ou aminoacides) sont une classe de composés chimiques possédant deux groupes fonctionnels : à la fois un groupe carboxyle –COOH et un groupe amine –NH2. Parmi ceux-ci, les acides α-aminés se définissent par le fait que leur groupe amine est lié à l'atome de carbone adjacent au groupe acide carboxylique (le carbone α), ce qui leur confère la structure générique H2N–CHR–COOH, où R représente la chaîne latérale, qui identifie l'acide α-aminé.
Les acides α-aminés jouent un rôle fondamental en biochimie comme constituants élémentaires des protéines : ils polymérisent en formant des liaisons peptidiques qui aboutissent à de longues chaînes macromoléculaires appelées peptides.
Analyse thermique
Biopolymères -- Synthèse
Caractérisation
ChitosaneLe chitosane ou chitosan est un polyoside composé de la distribution aléatoire de D-glucosamine liée en ß-(1-4) (unité désacétylée) et de N-acétyl-D-glucosamine (unité acétylée). Il est produit par désacétylation chimique (en milieu alcalin) ou enzymatique de la chitine, le composant de l'exosquelette des arthropodes (crustacés) ou de l'endosquelette des céphalopodes (calmars...) ou encore de la paroi des champignons. Cette matière première est déminéralisée par traitement à l'acide chlorhydrique, puis déprotéinée en présence de soude ou de potasse et enfin décolorée grâce à un agent oxydant. Le degré d'acétylation (DA) est le pourcentage d'unités acétylées par rapport au nombre d'unités totales, il peut être déterminé par spectroscopie infrarouge à transformée de Fourier (IR-TF) ou par un titrage par une base forte. La frontière entre chitosane et chitine correspond à un DA de 50 % : en deçà le composé est nommé chitosane, au-delà , chitine. Le chitosane est soluble en milieu acide contrairement à la chitine qui est insoluble. Il est important de faire la distinction entre le degré d'acétylation (DA) et le degré de déacétylation (DD). L'un étant l'inverse de l'autre c'est-à -dire que du chitosane ayant un DD de 85 %, possède 15 % de groupements acétyles et 85 % de groupements amines sur ses chaînes.
Le chitosane est biodégradable et biocompatible (notamment hémocompatible). Il est également bactériostatique et fongistatique.
Le chitosane est également utilisé pour le traitement des eaux usées par filtration ainsi que dans divers domaines comme la cosmétique, la diététique et la médecine.
Glutaraldéhyde
hydrocolloïdes
Morphologie (matériaux)
Réticulation (polymérisation)
Stabilité thermiqueIndex. décimale : 668.9 Polymères Résumé : Chitosan & L-alanine and chitosan & L-leucine superabsorbent hydrogels were prepared by crosslinking chitosan with glutaraldehyde. L-alanine and L-leucine were used as amino acid structures in different loading degrees and the optimum amount of amino acid was determined for both types of hydrogel. The swelling behaviors of neat chitosan, chitosan & L-alanine and chitosan & L-leucine hydrogels were investigated by gravimetric measurements with different pH values and at different intervals of time. The neat chitosan, chitosan & L-alanine and chitosan & L-leucine hydrogels were characterized by Fourier transform infrared spectroscopy (FT-IR). Thermogravimetric Analysis (TGA) and Differential Scanning Calorimetry (DSC) were used to find the thermal stability of the hydrogels. Also, surface morphological studies of all the hydrogels were carried out by using a Scanning Electron Microscope (SEM). In addition, XRD analysis demonstrated significant changes in the characteristic and morphological structures of the hydrogels. Note de contenu : - Materials
- Effect of amount of amino acid in swelling behavior of hydrogels
- Effect of pH in swelling behavior of hydrogels
- Structural and morphological characterization of hydrogelsDOI : 10.3139/217.2869 En ligne : https://drive.google.com/file/d/1sV8MUUAfA7KabjNwWgEARD8ufe3ZJS35/view?usp=drive [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=21324
in INTERNATIONAL POLYMER PROCESSING > Vol. XXIX, N° 2 (05/2014) . - p. 287-294[article]Réservation
Réserver ce document
Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité 16222 - Périodique Bibliothèque principale Documentaires Disponible Synthesis of eco-friendly polymeric resins and their rote in making leather with improved retanning properties and wastewater pollution / Muhammad Naveed Ashraf in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC), Vol. 104, N° 6 (11-12/2020)
[article]
Titre : Synthesis of eco-friendly polymeric resins and their rote in making leather with improved retanning properties and wastewater pollution Type de document : texte imprimé Auteurs : Muhammad Naveed Ashraf, Auteur ; Shahzad Maqsood Khan, Auteur ; Shahid Munir, Auteur Année de publication : 2020 Article en page(s) : p. 288-299 Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Biopolymères
Biopolymères -- Synthèse
Cuir -- Teneur en formaldéhyde
Cuirs et peaux -- Propriétés mécaniques
Cuirs et peaux -- Propriétés organoleptiques
Eaux usées -- Analyse
Fourier, Spectroscopie infrarouge à transformée de
Glutaraldéhyde
MélamineLa mélamine, de nom chimique 1,3,5-triazine-2,4,6-triamine, est parfois dénommée cyanuramide ou cyanurotriamine. Sa formule brute est C3H6N6.
Les "résines mélamine-formaldéhyde" ou "mélamine-formol" (sigle MF) sont appelées "mélamine" dans le langage courant. Elles font partie de la famille des aminoplastes qui regroupe des résines thermodurcissables aminées, issues d'un comonomère tel l'urée ou la mélamine, parfois le thiocarbamide, le cyanamide hydrogène ou le dicyandiamide ; le second comonomère étant le formaldéhyde.
Morphologie (matériaux)
Poids moléculaires
Polymères -- Synthèse
Retannage
Rhéologie
Sulfanilique, Acide
ThermogravimétrieIndex. décimale : 675.2 Préparation du cuir naturel. Tannage Résumé : In this work a novel and eco-friendly retanning agent was developed to eliminate the potential risk of formaldehyde occurrence in leather along with improving the characteristics of leather. A series of sulfanilic acid modified melamine-glutaraldehyde resins were produced at varied mole ratios of melamine, glutaraldehyde and sulfanilic acid. The glutaraldehyde to melamine mole ratio (GL/M) was varied from 2 to 6 whereas the sulfanilic acid to melamine mole ratio (SNA/M) was varied from 0.5 to 3. The viscosity trend of resins in the series was studied.
Synthesised resins were used in retanning leather in comparison with a melamine-formaldehyde resin as a control. Retanned pieces of leather were evaluated for their mechanical properties and organoleptic properties. Samples of leather retanned with the optimal resin were also analysed for comparative free formaldehyde determination. Scanning electron microscopy was performed to study the morphology of grain surface and fibre structure of resulting leather. Effluent received from retanning process was analysed for pollution load estimation. The optimum resin was subjected to determination of its molecular weight, to thermo gravimetric analysis and FTIR. It was obvious from the results of this study that the optimal resin produced a leather with improved mechanical and organoleptic properties in comparison with the control.
Estimation of formaldehyde content in leather proved the complete elimination of free formaldehyde in leather whereas the level in control leather was 152mg/kg. Results from the pollution load study of waste water confirmed an improvement in efficiency of COD, TDS, TSS and formaldehyde by 13.40%, 9.71%, 8.82% and 100% respectively. SEM monographs of grain surface and collagen fibres showed better filling, distribution and reactivity of the optimal resin. Thermo gravimetric analysis proved the increase in thermal stability of developed resin by 16.3% as compared to control. The eco-friendly condensation polymer produced in this work was considered suitable for making formaldehyde-free leather with improved retanning properties, thermal stability and pollution load.Note de contenu : - EXPERIMENTAL PROCEDURE : Chemicals and apparatus - Preparation of sulfanilic acid modified melamine-glutaraldehyde resins (MGLSNA)
- RESULTS AND DISCUSSION : Schematic route of synthesis - Viscosity trend in MGLSNA series - Leather application of MGLSNA resins - Mechanical properties of retanned leather - Organoleptic properties of leather - Comparative SEM analysis of leather - Quantitative estimation of fre formaldehyde content in leather - Molecular weight determination of optimal MGLSNA resin - Thermo gravimetric analysis - Structural elucidation through FTIR - Effluent analysis
- Table 1 : Mole ratios and physical characteristics of prepared MGSLNA resins - Experimental data
- Table 2 : Leather processing materials, conditions and recipe
- Table 3 : Mechanical characteristics of leather retanned with resins MGLSNA
- Table 4 : Dependence of flow time, relative viscosity, specific viscosity, Δ, ηsp - inηr and Δ/c2 different concentrations of MGLSNA resin #08
- Table 5 : Comparative pollution load reduction efficiency of optimum MGLSNA resin
- Scheme 1 : Formation of hydroxy derivatives of melamine
- Scheme 2 : Preparation of sodium salt of sulfanilic acid
- Scheme 3 : Sulfonation of hydroxy derivatives of melamine
- Scheme 4 : Condensation of monomers to produce resin MGLSNA
- Fig. 1 : Comparative study of organoloeptic properties of MGLSNA resins
- Fig. 2 : Scanning electron micrographs of cross section of grain surface (X50) and collagen fibre (X500)
- Fig. 3 : Dependence of Δ/c2 on the concentration of optimal resin MGLSNA#08
- Fig. 4 : TGA of optimal resin MGLSNA#08 and commercial melamine resin
- Fig. 5 : FTIR of MGLSNA#08 resinsEn ligne : https://drive.google.com/file/d/1ebHKU_sNQN0nAZXxMvUEazp3CWa7RHtj/view?usp=drive [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=34910
in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC) > Vol. 104, N° 6 (11-12/2020) . - p. 288-299[article]Réservation
Réserver ce document
Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité 22440 - Périodique Bibliothèque principale Documentaires Disponible The further investigation of tanning mechanisms of typical tannages by ultraviolet-visible and near infrared diffused reflectance spectrophotometry / Junling Guo in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. CVI, N° 7 (07/2011)
[article]
Titre : The further investigation of tanning mechanisms of typical tannages by ultraviolet-visible and near infrared diffused reflectance spectrophotometry Type de document : texte imprimé Auteurs : Junling Guo, Auteur ; Xin Huang, Auteur ; Chao Wu, Auteur ; Xuepin Liao, Auteur ; Bi Shi, Auteur Année de publication : 2011 Article en page(s) : p. 226-231 Note générale : Bibliogr. Langues : Américain (ame) Catégories : Alun
Glutaraldéhyde
Groupement carboxyle
Spectrométrie infrarouge
Spectrophotométrie UV-Visible
Spectroscopie de réflectance
Sulfate d'aluminium
Sulfate de chrome
Sulfate de fer
Sulfate de titane
Sulfate de zirconium
Tannage
Tannage végétalIndex. décimale : 675.2 Préparation du cuir naturel. Tannage Résumé : The ultraviolet-visible and near-infrared diffuse reflection (UV-Vis-NIR DR) spectroscopy was employed for further understanding the mechanisms of three kinds of classical tannages, including aldehyde tanning, vegetable tanning and mineral tanning. The NIR DR spectra of glutaraldehyde tanned leather exhibited a decreased peak intensity of amino group at 1475 nm, suggesting that the main reaction groups of collagen in aldehyde tanning are amino groups. Comparing the NIR DR spectra of pickled pelt and vegetable tanned leather, it was proved that the vegetable tanning is based on the mechanism of multiple hydrogen bonding interaction, where the amino groups, carboxyl groups and peptide chains are involved. As for mineral tannages, the tanning mechanisms of chromium sulfate, zirconium sulfate, ferrum sulfate, titanium sulfate and aluminum sulfate were investigated. Based on UV-Vis-NIR DR analysis in the wavelength range of 200 to 2070 nm, it was confirmed that the main reactions involved in mineral tanning are the chelating interactions of metal ions with both the carboxyl groups and the amino groups of collagen, although the reactivity of metal salts toward carboxyl groups is higher than toward amino groups. The reactivity of metal salts toward carboxyl groups of collagen follows the sequence of chromium salt > zirconium salt > ferrum salt > titanium salt > aluminum salt. However, the reactivity of metal salts to amino groups of collagen is in the sequence of zirconium salt > chromium salt > ferrum salt > titanium salt > aluminum salt. Meanwhile, the peptide chain of collagen was also found to play an important role in fixation of metal ions during tanning process. Note de contenu : EXPERIMENTAL : Preparation of leather samples - UV-Vis-NIR DR determinations.
RESULTS AND DISCUSSION : Comparison and analysis of DR spectra of CF, GA-CF and BT-CF - Comparison and analysis of DR spectra of metal salts tanned leathers.En ligne : https://drive.google.com/file/d/1XMCv5rwTd7b_YqA_uIwFpuqj1DFNGr8M/view?usp=drive [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=12032
in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA) > Vol. CVI, N° 7 (07/2011) . - p. 226-231[article]Réservation
Réserver ce document
Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité 013127 - Périodique Bibliothèque principale Documentaires Disponible The influence of solvents on hydrothermal stability and microstructure of combination tannage / Wang Yajuan in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC), Vol. 96, N° 2 (03-04/2012)
[article]
Titre : The influence of solvents on hydrothermal stability and microstructure of combination tannage Type de document : texte imprimé Auteurs : Wang Yajuan, Auteur ; Shan Zhihua, Auteur ; Jiang Lan, Auteur ; Wu Ningkun, Auteur ; Shao Shuangxi, Auteur Année de publication : 2012 Article en page(s) : p. 48-55 Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Alun
Cuirs et peaux
Glutaraldéhyde
Microscopie électronique à balayage
Microstructures
Mimosa et constituants
Oxazolidine
Stabilité hydrothermale
TannageIndex. décimale : 675.2 Préparation du cuir naturel. Tannage Résumé : The influence of solvents on combination tanned leather was established with observation of thermal stability, and the microstructure of the leather sample before and after shrinkage. Thermal stability of leather tanned with MI (mimosa), GA (glutaraldehyde, OZ (oxazolidine) and Al (aluminium sulphate) were reported using the shrinkage temperature for helix and random coil transition after soaking in O.5, 1.0 and 2.0 mo/L urea solution had a very obvious effect on GA-MI and MI-OZ-tanned leather, whose Ts reduced to 84,2°C and 84,6°C from 94,8°C and 100,9°C respectively. The influence of acidity and basicity of the solution also cannot be ignored, and OZ-MI leather was the most susceptible one whose Ts reduced to 85,3°C from 97,7°C the thermal stability of leather involving MI and Al can be affected remarkably by glycerin. All of the leather samples showed a more obvious Ts decrease when it was soaked from the dry state than in moist state.
Scanning electron microscope (SEM) studies revealed that the microstructure of collagen is destroyed when it shrinks and that the degree of destruction depends on the cross-linking agents.Note de contenu : - EXPERIMENTAL PROCEDURE : Materials - Preparation of leather samples - Solvent treatment - Micro-morphology of sample
- RESULTS AND DISCUSSION : Hydrothermal stability of MI and GA leather - Micro-morphology of MI and GA leather - Hydrothermal stability of MI and OZ leather - Micro-morphology of MI and OZ leather - Hydrothermal stability of MI and Al leather - Micro-morphology of MI and Al leatherEn ligne : https://drive.google.com/file/d/1h6CrbyREtmKMIjmL08MwCsp86RaHhf_0/view?usp=drive [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=14567
in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC) > Vol. 96, N° 2 (03-04/2012) . - p. 48-55[article]Réservation
Réserver ce document
Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité 13844 - Périodique Bibliothèque principale Documentaires Disponible Utilization of chromium-tanned leather solid wastes in microencapsulation / Bugra Ocak in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. CVI, N° 7 (07/2011)
[article]
Titre : Utilization of chromium-tanned leather solid wastes in microencapsulation Type de document : texte imprimé Auteurs : Bugra Ocak, Auteur ; Ahmet Aslan, Auteur ; Gürbüz Gülümser, Auteur Année de publication : 2011 Article en page(s) : p. 232-238 Note générale : Bibliogr. Langues : Américain (ame) Catégories : Collagène
Cuir -- Déchets
Encapsulation
Fourier, Spectroscopie infrarouge à transformée de
Glutaraldéhyde
Huile essentielle de lavande
Hydrolysats de protéines
Microscopie électronique à balayage
Récupération (Déchets, etc.)
Recyclage (déchets, etc.)
Tannage au chromeIndex. décimale : 675 Technologie du cuir et de la fourrure Résumé : In this research, solid collagen-based protein hydrolysate was isolated from chromium-tanned leather wastes and its chemical properties were determined. After that, the use of collagen hydrolysate (CH) was investigated as a polymeric wall material in the microencapsulation process. The effects of variations in concentrations of CH, lavender oil (LO) and glutaraldehyde (GA), which were used during the microencapsulation process, on the oil load of microcapsules, oil content, encapsulation efficiency and release rate of oil were determined. The morphological structure of the microcapsules was investigated using optical and scanning electron microscopes (SEM). It was determined by FTIR studies that there was no evidence for any significant interaction between CH and LO. Note de contenu : MATERIALS AND METHODS : Preparation of collagen hydrolysate - Phase separation behaviour of collagen hydrolysate - Preparation of microcapsules - Determination of some chemical characteristics of collagen hydrolysate - Calibration curve of lavender oil - Determination of the oil load, oil content and encpsulation efficiency - Oil release studies - Optical and scanning electron microscopy studies - FTIR study.
RESULTS AND DISCUSSION : Some chemical characteristics of collagen hydrolysate - The effect on microcapsules of variations in oil concentration - Effects of variation of hydrolysate concentration - The effect of variation in glutaraldehyde concentration - Optical and scanning electron microscopic studies - Fourier Transform Infrared (FTIR) study.En ligne : https://drive.google.com/file/d/1vpL-zU-enBe_sD-OaV0OOevqpaXvpKVM/view?usp=drive [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=12033
in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA) > Vol. CVI, N° 7 (07/2011) . - p. 232-238[article]Réservation
Réserver ce document
Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité 013127 - Périodique Bibliothèque principale Documentaires Disponible Visualization of penetration and reaction of aldehyde tanning agent in leather using fluorescence technique / Ying Song in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. CXV, N° 7 (07/2020)
PermalinkWashability of glutaraldehyde-chrome tanned garment and glove leathers / S. J. Viola in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. LXI (Année 1966)
PermalinkWater sorption capacity of tanned collagen fibres / K. J. Bienkiewicz in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC), Vol. 61 et 62 (Années 1977 et 1978)
PermalinkYield of chrome tanned side leather / Samir Das Gupta in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC), Vol. 66 (Année 1982)
Permalink