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Synthesis, characterisation and application of environment friendly polymers for producing sustainable leather / Muhammad Naveed Ashraf in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC), Vol. 105, N° 1 (01-02/2021)
[article]
Titre : Synthesis, characterisation and application of environment friendly polymers for producing sustainable leather Type de document : texte imprimé Auteurs : Muhammad Naveed Ashraf, Auteur ; Shazad Maqsood Khan, Auteur ; Shahid Munir, Auteur ; Rashid Saleem, Auteur Année de publication : 2021 Article en page(s) : p. 19-30 Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Biopolymères -- Synthèse
Caractérisation
Cuirs et peaux -- Propriétés mécaniques
Cuirs et peaux -- Propriétés organoleptiques
Eaux usées -- Analyse
Formaldéhyde -- Suppression ou remplacement
Mélamine-Méthylglyoxal
Poids moléculaires
Retannage
Rhéologie
Stabilité thermique
ThermogravimétrieIndex. décimale : 675 Technologie du cuir et de la fourrure Résumé : A series of formaldehyde-free melamine-methylglyoxal resins has been produced at various mole ratios of reactants. The methylglyoxal to melamine mole ratio (MG/M) was varied from 3 to 6 and the sodium metabisulfite to melamine mole ratio (SMB/M) was varied from 0.05 to 0.2. Viscosity trend of resins within the series was examined. The prepared resins were used as retanning agents and their improved mechanical and organoleptic properties were noticed in comparison with a commercial melamine-formaldehyde resin. The morphology of grain surface and fibre structure of the leathers was investigated by scanning electron microscopy (SEM). Thermal stability of the optimal resin was assessed and observed to show an improvement over the commercial melamine-formaldehyde resin. Molecular weight and FTIR study of optimal resin was also pursued. Determination of free formaldehyde confirmed that the resulting leather was free from formaldehyde. A pollution load study of retanning effluent showed a significant reduction in chemical oxygen demand, total suspended solids and total dissolved solids for the optimal resin reflecting its improved exhaustion due to optimised molecular size and ability to undergo in situ polymerisation in collagen fibres. The results have shown that the melamine resins of this novel work are suitable for producing formaldehyde-free leather with improved retanning properties and reduced pollution load of the wastewater. Methylglyoxal has been proved as a successful alternate of formaldehyde in resin synthesis to control air emissions and carcinogenic effects while producing sustainable leather. Note de contenu : - EXPERIMENTAL PROCEDURE : Chemicals and apparatus - Synthesis of novel melamine resins using methylglyoxal as a condensing agent
- RESULTS AND DISCUSSION : Schematic route of synthesis - Rheology of resins - Evaluation of retanning performance of SMMG resins - Mechanical proerties of leather treated with SMMG resins - Organoleptic properties of the leather treated with novel SMMG resins - Quantitative estimation of free formaldehyde content in treated leather - Molecular weight determination of optimal SMMG resin - Structural elucidation of optimal SMMG resin - Comparative thermo gravimetric analysis of optimal SMMG resin - Analysis of effluent
- Table 1 : Mole ratio and physical characteristics of novel SMMG resins - Experimental data
- Table 2 : Leather processing materials, conditions and recipe
- Table 3 : Mechanical properties of leather treated with sulfonated melamine-methylglyoxal resins
- Table 4 : Dependence of flow time, relative viscosity, specific viscosity
- Table 5 : Comparative characteristics of effluent after retanning with novel SMMG#06 resin and control resin
- Scheme 1 : Reaction of melamine and methylglyoxal at different mole ratio
- Scheme 2 : Sulfonation of melamine-methylglyoxal derivative
- Scheme 3 : Condensation of sulfonated tetrahydroxy melamine to form polymer moleculeEn ligne : https://drive.google.com/file/d/14IGqeHhbQcRyM88CW02qqG0GNzcv3Cr6/view?usp=drive [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=35314
in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC) > Vol. 105, N° 1 (01-02/2021) . - p. 19-30[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 22599 - 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
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Code-barres Cote Support Localisation Section Disponibilité 22440 - Périodique Bibliothèque principale Documentaires Disponible Synthesis of vanillin-based UV curable polyurethane dispersions for wood coating applications / Darshan Mahajan in JOURNAL OF COATINGS TECHNOLOGY AND RESEARCH, Vol. 20, N° 5 (09/2023)
[article]
Titre : Synthesis of vanillin-based UV curable polyurethane dispersions for wood coating applications Type de document : texte imprimé Auteurs : Darshan Mahajan, Auteur ; Darbha Sai Srivats, Auteur ; Aarti More, Auteur Année de publication : 2023 Article en page(s) : p. 1773-1788 Note générale : Bibliogr. Langues : Américain (ame) Catégories : Biopolymères
Biopolymères -- Synthèse
Bois -- Revêtements
Caractérisation
Chimie analytique
Composés organiques -- Synthèse
Dispersions et suspensions
Enrobage (technologie)
Formulation (Génie chimique)
Polymères en émulsion
Polyuréthanes
Résistance aux taches
Résistance chimique
Revêtements -- Propriétés mécaniques
Revêtements en phase aqueuse
Revêtements organiquesIndex. décimale : 667.9 Revêtements et enduits Résumé : Partial incorporation of bio-based diol in the synthesis of UV-curable polyurethane dispersion (PUDs) has been studied. The bio-based diol was synthesized from vanillin. Divanillin (DV) was used as a partial replacement for polyethylene glycol an industrial diol. PUDs were synthesized by reacting vanillin and polyethylene glycol in different percentages (10:90, 30:70, and 50:50) with isophorone diisocyanate along with 2-dimethyl propionic acid. Hydroxyethyl methacrylate is attached to incorporate unsaturation, which helps in the UV curing process, and triethyl amine is used for acid group neutralization. The synthesis of DV and resin was confirmed by FTIR spectroscopy. Divanillin synthesis confirmation was carried out by NMR spectroscopy. The synthesized resin was dispersed in water and applied on a wooden panel. Mechanical testing, like scratch resistance, pencil hardness, and cross-hatch adhesion tests, was carried out on the cured coatings to determine their properties. The 30% incorporation of DV shows the highest pencil hardness (2H) and scratch hardness (0.90 kg) among all the DV formulations and the results were comparable to plain formulation. The 30% DV also exhibits good gloss at 60° angle with value of 76.7. Coatings exhibited excellent acid resistance and moderate resistance towards alkalis. TGA was performed on the plain PU and 30% DV and the onset temperatures were 190 °C and 185 °C, respectively. All the dispersions formed were tested to determine their particle size, and the particle size distributions were in the range of 3–55 µm. Gel content percentages for all the samples were in the range of 90–97%. Note de contenu : - EXPERIMENTAL : Materials - Synthesis of divanillin - Synthesis of polyurethane resin - Preparation of polyurethane dispersion and preparation of coating - Characterization
- RESULTS AND DISCUSSION : FTIR - NMR analysis - Contact angle - Mechanical properties - Chemical prperties - Thermogravimetric analysis (TGA) - Particle size analysis of polyurethane dispersion - Gel content
- Table 1 : Formulations of synthesized resin with different ratios of divanillin (DV) to PEG
- Table 2 : Results of mechanical properties
- Table 3 : Chemical resistance of the coating
- Table 4 : Stain resistance of coating
- Table 5 : Polyurethane dispersion particle diameter values after synthesis (D10, D50, and D90)
- Table 6 : Polyurethane dispersion particle diameter values after 6 months (D10, D50, and D90)DOI : https://doi.org/10.1007/s11998-023-00780-9 En ligne : https://link.springer.com/content/pdf/10.1007/s11998-023-00780-9.pdf?pdf=button% [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=39987
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Code-barres Cote Support Localisation Section Disponibilité 24242 - Périodique Bibliothèque principale Documentaires Disponible Utilization of agricultural by-products to partially replace gelatin in preparation of products for leather / Maryann M. Taylor in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. CX, N° 1 (01/2015)
[article]
Titre : Utilization of agricultural by-products to partially replace gelatin in preparation of products for leather Type de document : texte imprimé Auteurs : Maryann M. Taylor, Auteur ; Lorelei P. Bumanlag, Auteur ; J. Lee, Auteur ; Nicholas P. Latona, Auteur ; Eleanor M. Brown, Auteur ; Cheng-Kung Liu, Auteur Année de publication : 2015 Article en page(s) : p. 13-18 Note générale : Bibliogr. Langues : Américain (ame) Catégories : Biopolymères -- Synthèse
Gélatine -- Produits de remplacement
Glucides
Polyphénols
Ressources agricoles
Wet-white (tannage)Index. décimale : 675 Technologie du cuir et de la fourrure Résumé : When polyphenolic-modified gelatin-products were used as fillers, improvements were seen in the subjective properties of the leather. When the treated samples were compared to control samples, there were no significant changes in mechanical properties. At the present time, gelatin is in short supply, costs are increasing, and there is an urgent need to find a substitute that could be combined with the gelatin, thereby, partially replacing and reducing the amount of gelatin required, with the goal that the new products would retain the desired characteristics of gelatin products. We have evaluated the potential of producing biopolymers from the reaction of polyphenols with gelatin in combination with other proteins (e.g. whey) or with carbohydrates (e.g. chitosan and pectin). Several researchers have recently demonstrated the feasibility of these reactions. These combinations would take advantage of the distinctive properties of both species and at the same time create products with improved functional properties. Recently, the preparation of polyphenolic-modified gelatin/whey biopolymer products was investigated, and the results of product characterization using physicochemical analyses indicated optimal products that could be used as fillers. In this continuing study, these products were applied to wet white, that was then finished, and subjective and mechanical properties were evaluated. At the same time a method was developed to determine the rate of uptake of the product. Results of the studies will be presented. These findings could further add to the knowledge of using renewable resources in production of unique products that may have leather processing application. Note de contenu : - MATERIALS : Application of gelatin/WPC/tara product to wet white stock (area samples)
- ANALYSES : Physical properties, mechanical properties and molecular weight distribution - Subjective evaluation RCF leather - Optical microscopy (with epi-fluorescent attachment) - Scanning Electron Microscopy (SEM) - Protein concentration determination
- TREATMENT OF WET WHITE AND BCA ANALYSIS
- SEM AND EPI-FLUORESCENT IMAGERYEn ligne : https://drive.google.com/file/d/1osGv9Qvyx2UsJkmJJiM0aPJ5INeYQq8_/view?usp=drive [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=22792
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Code-barres Cote Support Localisation Section Disponibilité 16774 - Périodique Bibliothèque principale Documentaires Disponible