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Negative effects of haloversatile bacteria in salt on skins and their control with direct electric current in the leather industry / Haider Sabah Abdulhusein in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC), Vol. 107, N° 6 (11-12/2023)  

[article]  inJOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC) > Vol. 107, N° 6 (11-12/2023) . - p. 207-214 Titre : Negative effects of haloversatile bacteria in salt on skins and their control with direct electric current in the leather industry Type de document : texte imprimé Auteurs : Haider Sabah Abdulhusein, Auteur ; Pinar Caglayan, Auteur ; Meral Birbir, Auteur ; Yasar Birbir, Auteur Année de publication : 2023 Article en page(s) : p. 207-214 Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Bactéries haloversatiles Courants continus Cuirs et peaux -- Conservation Cuirs et peaux de chèvres Cuirs et peaux de moutons Microbiologie Sels de sodium Index. décimale : 675 Technologie du cuir et de la fourrure Résumé : The salt preservation method has been used for a long time in the leather industries with salt applied to raw skins and hides in order to control bacterial activity and to remove the moisture found in the skin structure. It is known that the salt used in curing process contains many halophilic bacterial species. During the salting process, skins and hides might be contaminated with these micro-organisms. The goal of this research was to determine factors including the pH of salt samples, total count of haloversatile bacteria, proteolytic haloversatile bacteria, and lipolytic haloversatile bacteria found in these samples and to isolate, and identify haloversatile bacteria from the salt samples, to test their ability to use various amino acid and sugar sources, to characterise their enzymatic properties, to investigate their adverse effects on sheepskinand goatskin samples using a scanning electron microscopy. In addition, 2.5A direct electric current was applied against mixed culture of enzyme-producing haloversatile bacteria in 15% NaCl solution to search for an alternative environmentally friendly preservation method for skin/hide curing. The pH values of salt samples were found to be between 7.60 and 8.04. The total counts of haloversatile bacteria, proteolytic haloversatile bacteria and lipolytic haloversatile bacteria were found to be 6 × 103CFU/g to 1.3 × 105CFU/g; 1×103-7×103CFU/g and 1.4 × 103-3.1 × 104CFU/g, respectively. 35 haloversatile bacteria belonging to ten different genera (Staphylococcus, Corynebacterium, Peribacillus, Lysinibacillus, Kocuria, Paenibacillus, Bhargavaea, Bacillus, Pseudomonas and Micrococcus) were isolated and identified from the salt samples. The ability of haloversatile bacteria to use sugars and amino acids varied from one genus to another genus. While catalase, esterase, urease, protease, caseinase, lipase, xylanase, cellulase, amylase, DNase and oxidase enzymes were produced among the isolates, pullulanase enzyme was not produced. The scanning electron microscope micrographs showed that enzyme-producing haloversatile bacteria had significant effects on goatskin and sheepskin. The total number of the mixed culture was reduced from 3.6 × 106CFU/mL to 4×101CFU/mL within 17 minutes, and all cells were completely killed within 21 minutes. The scanning electron micrographs showed that the structure and the organoleptic characterictics of bacteria treated sheepskin and goatskin samples were negatively changed at the end of 40-days storage. Note de contenu : - Salt sample collection and measuring pH value of salt samples - Determination of the total numbers of haloversatile bacteria in the salt samples - Determination of the total numbers of proteolytic and lipolytic haloversatile bacteria in salt samples - Isolation of haloversatile bacteria - Identification of haloversatile isolates according to 16S rRNA gene sequence analyses - Nucleotide accession number - Effects of different NaCl concentrations, pH values and temperature on haloversatile bacterial growth - Investigation of enzymatic properties of haloversatile bacteria - Utilisation of different amino acids and different carbon sources by haloversatile bacteria - Investigation the effects of the mixed culture of enzyme producing haloversatile isolates on sheepskin and goatskin - Extermination of haloversatile bacteria by direct electric current - Investigation of the bacterial cells before and after the treatment with direct electric current by scanning electron microscopy - Table 1 : The pH values, total counts of haloversatile bacteria, proteolytic haloversatile bacteria and lipolytic haloversatile bacteria in the salt samples - Table 2 : The effects of pH, NaCl contents and temperature values on bacterial growth - Table 3 : Enzymatic properties of haloversatile bacterial isolates - Table 4 : Utilization of different amino acids by haloversatile isolates - Table 5 : Utilisation of different sugars by haloversatile isolates - Table 6 : The pH values, temperature and the total counts (CFU/mL) of enzyme producing haloversatile bacteria in the direct electric current treatment En ligne : https://drive.google.com/file/d/1qRfWv_CwzI3WQkn8QhrK0n0Rq2zPAjwb/view?usp=drive [...] Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=40239 [article]

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Synthesis and application of a polymer auxiliary with silicone / Lu Tao in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC), Vol. 107, N° 6 (11-12/2023)  

[article]  inJOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC) > Vol. 107, N° 6 (11-12/2023) . - p. 215-220 Titre : Synthesis and application of a polymer auxiliary with silicone Type de document : texte imprimé Auteurs : Lu Tao, Auteur ; Luo Jianxun, Auteur ; Feng Yanjuan, Auteur Année de publication : 2023 Article en page(s) : p. 215-220 Note générale : Bibliogr. Langues : Anglais (eng) Catégories : acrylique, Acide L'acide acrylique ou acide acroléïque ou acide prop-2-énoïque est un composé organique de formule brute C3H4O2 et de formule semi-développée CH2=CHCOOH. C'est un acide carboxylique et un alcène vinylique, et se présente comme un liquide incolore à l'odeur âcre. L'acide acrylique et ses esters, les acrylates, sont utilisés dans la fabrication de matières plastiques, dans les peintures acryliques et dans divers autres polyacryliques qui ont de multiples usages. Cuirs et peaux de moutons Douceur (toucher) Epaississement Formulation (Génie chimique) Méthacrylique, Acide L'histoire de l'acide méthacrylique commence en 1865, année où il est synthétisé pour la première fois à partir du méthacrylate d'éthyle. L'acide méthacrylique est très réactif avec les groupes carboxyles, vinyles et esters. Polyvinylsiloxane Retannage Tannage synthétique Index. décimale : 675 Technologie du cuir et de la fourrure Résumé : In order to reduce the apparent density of the finished leather and the amount of fatliquor used during leathermaking, a polymer auxiliary with silicone has been synthesised by radical co-polymerisation of acrylic acid, methacrylic acid and polyvinyl silicone oil etc. The polymers were applied in the re-tanning process of sheepskin. Comparing the viscosity and applied properties of the polymer auxiliary with silicone, the mol ratio of acrylic acid, methacrylic acid used was confirmed to be 0.5:0.2, the consumption of polyvinyl silicone oil, ammonium persulfate, the reactive temperature and time were 5%, 1.5%, 80-85°C, 120-180 minutes, respectively. Infrared spectroscopy shows that the structure of the polymer auxiliary contains -Si-O- bond. The thickening increase and softness of the treated leather are 23.1%, 6.0 and the consumption of fatliquoring agent after re-tanning can be reduced to 4~8% when the optimum consumption of the polymer auxiliary is 8~10%, the retreated leather is fine grained, soft, hydrophobic and the apparent density is 0.457g/cm3. Note de contenu : - EXPERIMENTAL PROCEDURES : Materials - Preparation of the polymer auxiliary with silicon - Application of series of the copolymers and the selection of the synthetic recipe - Molecular weight of the polymer auxiliary with silicone and its structure determination - Application and determination of the optimum amount of the polymer auxiliary with silicone on shaved sheepskin wet-blue - Application of the polymer auxiliary with silicone matched with other fatliquors on shaved sheepskin wet-blue - RESULTS AND DISCUSSION : Analysis of the optimised formulation of the copolymer - Analysis of the molecular weight and the structure of the optimised formulation of the copolymer and its characteristics - Results of application shaved sheepskin wet-blue of the polymer auxiliary with silicone - Results of application of the polymer auxiliary with silicone matched with other fatliquors on shaved sheepskin wet-blue - Table 1 : Parameters of orthogonal experiment - Table 2 : Formulation of copolymer reaction with acrylic acid, methylacrylic acid, polyvinyl silicone oil - Table 3 : The process of re-tanning and fatliquoring of the shaved sheepskin wet-blue based on the polymer auxiliary with silicone - Table 4 : Results of L9(34) copolymer reaction and application - Table 5 : Relationship between the bands and the relevant groups of the polymer auxiliary with silicone - Table 6 : Relation between the softness, apparent density of treated leather and the consumption of polymer auxiliary with silicone En ligne : https://drive.google.com/file/d/1pNkVE1xleX3xY_Zl9GsZAUCHpILajT4q/view?usp=drive [...] Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=40240 [article]

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Use of solid leather wastes to producte value-added material / M. A. Habib in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC), Vol. 107, N° 6 (11-12/2023)  

[article]  inJOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC) > Vol. 107, N° 6 (11-12/2023) . - p. 221-225 Titre : Use of solid leather wastes to producte value-added material : Mn3O4 nanoclusters by co-precipitation method using chrome shavings as a primary surface Type de document : texte imprimé Auteurs : M. A. Habib, Auteur ; N. H. El-Sayed, Auteur Année de publication : 2023 Article en page(s) : p. 221-225 Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Analyse morphologique Analyse thermique Chrome -- Recyclage Cuir -- Déchets Cuirs et peaux -- Déchets -- Recyclage Nanoparticules Oxyde de manganèse Précipitation (chimie) Valeur ajoutée Index. décimale : 675 Technologie du cuir et de la fourrure Résumé : Leather by-product wastes are significant ecosystem pollutants. Consuming these wastes to prepare valuable products is a noble target. In this work, a trial to consume chrome shavings to prepare fine- grade manganese oxide nanoclusters via a low-cost co-precipitation method was achieved. The co-precipitation was enhanced by developing the nanomaterial over chrome shaving leather waste. Manganese acetate purified powder was used as a starting material. The synthesised nanoclusters of manganese oxide were characterised by means of X-ray diffraction. The fine-grade prepared sample has been investigated by Scanning Electron Microscope (SEM) and Differential Thermal analysis. The crystalline size of the synthesised manganese oxide nanoparticle was obtained from X-ray diffraction, the sizes of particles ranged from 100 to 300nm. Therefore, the study establishes a scientific basis for the use of chrome shavings as a primary surface in the co-perception process for obtaining metal oxide nanoparticles. Note de contenu : - EXPERIMENTAL PROCEDURES : Materials - Synthesis of the samples - RESULTS AND DISCUSSION : Morphological analysis - Thermal analysis En ligne : https://drive.google.com/file/d/1ph3Hp8bsk23_oDV6OWEEzFuLnMUVYyVS/view?usp=drive [...] Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=40241 [article]

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Physical and fastness properties of leather dyed with a natural dye extracted from beetroot peels using a biomordant / Louret A. Andalo in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC), Vol. 107, N° 6 (11-12/2023)  

[article]  inJOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC) > Vol. 107, N° 6 (11-12/2023) . - p. 226-231 Titre : Physical and fastness properties of leather dyed with a natural dye extracted from beetroot peels using a biomordant Type de document : texte imprimé Auteurs : Louret A. Andalo, Auteur ; Paul K. M. Sang, Auteur ; Rose Tanui, Auteur Année de publication : 2023 Article en page(s) : p. 226-231 Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Acacia et constituants Colorants végétaux Cuirs et peaux -- Propriétés mécaniques Cuirs et peaux -- Propriétés physiques Cuirs et peaux -- Teinture Cuirs et peaux de chèvres Mordants (chimie) Post-tannage Tannage au chrome Index. décimale : 675 Technologie du cuir et de la fourrure Résumé : Leather dyeing is an essential process in the leather industry, where synthetic dyes are predominantly used. However, the environmental concerns associated with synthetic dyes have led to rising interest in natural dyes as sustainable alternatives. The use of biomordants is however, gaining attention due to their eco-friendly nature and potential to enhance dye fixation and colour fastness. This study aimed at determining the physical and fastness properties of leather dyed using natural dye extract from beetroot peels with the assistance of a biomordant derived from Acacia nilotica barks and banana pseudo stem sap. The dyeing process involved the use of the biomordant in both a pre and post-mordanting technique. Various fastness properties of dyed leather were investigated to assess the quality and durability of the dyeing process including water spotting fastness according to ISO 15700, mild washing fastness according to ISO 15703, and rub fastness (dry and wet rub fastness) according to ISO 11640. To determine the effect of the biomordant on the strength properties of the leather, the physical properties of the dyed leather were also evaluated. The tensile and tear strength of the dyed leather were measured on an Instron using IUP 6. The dye bath exhaustion was measured using spectrophotometric analysis. The dyed leatherʼs fastness properties were discovered to be good to excellent on a grey scale of 5. All of the samples exceeded the minimum recommended values (UNIDO 1996) for tensile strength (>20N/mm2), percentage elongation at break (>40%), and tear strength (>30N/mm). The samples dyed with Acacia nilotica bark as a biomordant had the highest dye bath exhaustion, followed by banana pseudo stem sap, and leather dyed without any mordant had the lowest dye bath exhaustion. According to the results obtained in this study, the use of biomordant in the dyeing of leather with natural dye from beetroot peels improved the fastness properties of the dyed leather as well as the strength of the resulting leather. Furthermore, the biomordant promoted dye uptake. Note de contenu : - MATERIALS AND METHODS : Materials - Methods - Physical properties of the dyed leather - RESULTS AND DISCUSSION : Analysis of the physical properties of the dyed leather - - Table 1 : Process for pre tanning goatskin - Table 2 : Process for chrome tanning of goat wet-blue - Table 3 : Post tanning process - Table 4 : Tensile strength and percentage elongation of the dyed leather - Table 5 : Tear strength of the dyed leather - Table 6 : Fastness properties of the dyed leather both the mordanted and the umordanted samples on a grey scale of 5 En ligne : https://drive.google.com/file/d/1G2w2KoZPKkzUblyRJeLJYFRmat4LDXbz/view?usp=drive [...] Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=40242 [article]

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