Fatliquoring Agent Research Articles

Fatliquor for fungus resistant leather-a sustainable ecofriendly approach

Surface-active softening agents, such as Fatliquors, have a significant impact on the leather industry as they enhance the physicochemical properties of leather. This study focuses on analyzing the synthesis, properties, characterization, and sulfonation of Swietenia mahagoni seed oil to determine its potential as a fatliquoring agent for leather. An investigation was conducted to verify the alteration of Swietenia mahagoni oil through the analysis of its properties before and after the sulfonation process. A scientific analysis was carried on the oil using GC-FID, revealing the presence of various unsaturated fatty acids such as linoleic, linolenic, oleic, palmitic, and arachidic acids. This demonstrates the sulfonating capability of this sky fruit seed oil. A fatliquor was created by sulfonating the oil, and the sulfonation was verified through Fourier Transform Infrared Spectroscopy (FTIR) and 1H Nuclear Magnetic Resonance (NMR) spectra. The prominent peak observed at 1209 cm-1 in the FTIR spectra indicated the stretching of S=O in both sulfate and sulfonate groups. The newly formed protons (H–C–S or H–C–O) showed signals between δ 4.09 and 4.29 ppm in the 1H NMR spectra, confirming the sulfonation of the fatliquor that was prepared. Moreover, the change in the melting point of sulfonated Mahogany oil from 40.8 °C to 48.1 °C suggests increased saturation levels. The fatliquor's emulsion stability was found to be at a satisfactory level. After conducting tests on the treated leather, the physical strength and morphological structure was analyzed using Field Emission Scanning Electron Microscopy (FE-SEM), the fatliquor improved the lubrication and strengthened the fibrous network structure of the leather, composed of thin and tight collagen fibers. The BOD5/COD ratio of the effluent from the experimental trial was determined to be 0.52, suggesting that the fatliquor developed is a biodegradable product. Finally, the antifungal capabilities of the fatliquor-treated leather were tested against four different fungus species: Aspergillus niger, Aspergillus flavus, Penicillium notatum, and Candida albicans, and the treated leather sample shown favorable antifungal activity.

Toward low-misting leathers from environmentally friendly ricinoleic acid-based fatliquoring agents

In this work, an amidated hydroxylated ricinoleic acid (MRH) was developed from natural ricinoleic acid and commercially available thioglycerol and monoethanolamine by simple and efficient thiol-ene click and amidation reactions. The resulting MRH was subsequently used as an environmentally friendly, low-misting fatliquor for premium automotive interior leathers. In addition, theoretical speculations using molecular dynamics simulations and routine experimental methods for determining the misting resistance and the percentage of free oil in the MRH-treated leather were systematically investigated. The hydroxyl groups and the amide group within MRH are able to form firm chemical bonds with collagen fibers of the leather, as evidenced by higher Ebinding (122.84 kcal/mol) and lower diffusion coefficient (0.000095 Å2/ps) obtained from molecular dynamics simulations, the lower free oil content (11.42%), and the lower misting value (4.82 mg) of MRH-treated leather. Therefore, the MRH fatliquoring agent did not migrate out of the collagen fibers. Overall, bio-derived ricinoleic acid can be modified to enable the design of sustainable fatliquors for low-misting-value automotive upholstery leather. Furthermore, the fatliquoring effluent was also biodegradable, all of which contributed to a cleaner production of leather fatliquor.

Interaction between Amphoteric Polymer and Silicic Acid Tanned Leather

Silicic acid-based tanning system is an effective and promising chrome-free tanning technology, and it is urgent to develop compatible post-tanning processes. Fatliquoring is one of the key procedures to determine the quality of resulted leather and fatliquoring agents mainly play the role of an effective softer/ plasticizer in leather production. However, there is a mismatch between most commercial fatliquoring agents (mainly compatible with chrome tanned leather) and silicic acid tanned leather (named SATL). Herein, an amphoteric polymer emulsion (APE) was prepared by free radical polymerization using methacryloxyethyl trimethyl ammonium chloride (DMC), 2-acrylamido-2-methylpropanesulfonate (AMPS), lauryl methacrylate (LMA), dimethylaminoethyl methacrylate (DMAEMA) as monomers. And in order to improve the lubricating property, APE was further compounded with castor oil to obtain an amphoteric fatliquoring agent (named COAPE). Comprehensive characterization showed that the amphoteric (pI=8.22) and amphiphilic APE could reduce the surface tension of water to 38.6 mN/m. The fatliquoring process was controlled by ingenious regulation of pH based on isoelectric points (pIs) of APE and SATL. In the initial stage, the pH of the bath was adjusted to be lower than the pIs of APE and SATL, amphoteric polymer molecules could easily penetrate into SATL leather as they are all positively charged. While during the fixing stage, the pH of the bath was adjusted between the pIs of APE and SATL, so the electrostatic interaction between amphoteric polymer molecules and SATL leather, as well as the aggregation of amphoteric polymers can promote their combination synergistically. As a fatliquoring agent, the application of COAPE demonstrated that its absorpotion rate (90.5%) was much higher than anionic commercial fatliquoring agent (63.2%), thus imparting SATL leather better softness (6.5 mm), elongation at break (95.5%) and tensile strength (11.6 N/mm2). These findings therefore provided scientific basis and technical support for the application of amphoteric materials to silicic acid-modified collagen matrix and would promote the practical application of silicic acid-based chrome-free tanning technology

Fatliquor Development from Hemp Oil to Produce High Quality Natural Finished Leather

Fatliquors are very important in the manufacture of leather. Leather treated with fatliquor become more flexible and softer by the separation of leather fibers in the wet state so that they do not stick too much during drying, also the physical properties, such as tensile strength, softness, tear strength and stability of the leather become influenced simultaneously. The step of fatliquoring is carried out during leather processing operation after tanning. Variety of fatliquors is synthesized so far from various vegetable oils. In this study, for the first time, fat-liquor, named as, “Hempfat” is synthesized from oil extracted from hemp seeds. As hemp oil consists of high amount of omega-6, omega-3 fatty acids possessing antioxidant activities, so accepted as beneficial to health for public, also possess high kinetic stability and increased protective effect during increase or decrease of temperature. On high temperatures, trans-fatty acids are not formed. So the developed fatliquor, “Hempfat” and the leather developed from it were evaluated on physical and chemical grounds, both found to possess the excellent properties of a fatliquor as leather fatliquoring agent in making good quality finished natural leather.

Leather Fatliquoring Agent from Camel Hump Fat

Leather Fatliquoring Agent from Camel Hump Fat

Effect of using fresh palm oil and used palm oil as a fatliquoring agent to the physical quality of tilapia fish skin in vegetable tannery

Fish skin is one of the alternative materials to replace the common animal skin that used in the leather tannery. This research was carried out by vegetable tanning to the tilapia fish skin using selected concentration of fresh palm oil and used palm oil. The study aims to find out the physical quality of leather through the using of fresh and used palm oil as fatliquoring agent in the vegetable tannery process. The same concentration of fresh palm oil (5%) and used palm oil (5%) were used in this study. The parameter of tensile strength, elongation, and shrinkage temperature as physical quality was observed in triplicates. Based on the results, tensile strength and leather elongation were significantly increased, while the shrinkage temperature was not significantly affected. In conclusion, the addition of palm oil caused the increasing tilapia fish skin quality that can be used for commercial products, and it became the alternative material that could be use in vegetable tannery processing.

Improvement of hydrothermal stability and chrome uptake of leather: Amino-terminated hyper-branched polymer as high exhausted tanning auxiliary

Carboxyl-terminated hyper-branched polyester is extensively used as high exhaustion chrome tanning auxiliary owing to its strong coordination ability with trivalent chrome. Owing to lower electronegativity of N than O, the coordination ability with trivalent chrome for hyper-branched polyamide is stronger than polyester. Herein, in this paper, an amino-terminated hyper-branched polyamide (HBPN) is synthesized and used as high exhaustion chrome in tanning of pickling pigskin (HBPN–Cr). The effects of utilization of HBPN in denaturation temperature, shrinkage temperature, chrome uptake, and microstructure structure of wet-blue leather are studied. Moreover, the anti-oxidation stability of wet-blue leather is preliminary studied by heat treatment. The results show that incorporation of 1% HBPN in pickling process can significantly improve chrome uptake to 83.32%. The hydrothermal stability of wet-blue leather is improved due to the formation of higher crosslinking degree of collagen fibers. In addition, for the wet-blue leather without unsaturated fatliquoring agent, through heat treatment, hexavalent chrome does not appear after 24 ​h heat treatment. On the contrary, the chrome complex changes from hydroxyl copolymerization to more stable oxygen copolymerization or chrome oxide for C–Cr and HBPN-Cr tanned leather, respectively. These results will build a data support for the further study of hyper-branched polymer chrome tanning auxiliaries.

Preparation and application of dialdehyde nanocellulose reinforced jatropha oil based polymer emulsions as leather fatliquors

Bio-based acrylated epoxidized jatropha oil (AEJO) was developed using a solvent-free synthetic method, and the structure of the resulting product was confirmed by Fourier transform infrared spectroscopy and proton nuclear magnetic resonance (1H NMR) spectra. Subsequently, an amphiphilic polymer emulsion AEJO-AA was prepared by emulsion polymerization using acrylic acid (AA) and AEJO. Moreover, 2, 3-dialdehyde nanocellulose (DNC) was prepared and combined with AEJO-AA emulsion as a fatliquoring agent for goatskin upper leather. The fatliquored leather shows improved mechanical strength and thermal stability. When the DNC loading is 1.5 wt%, the fatliquored leather exhibits the highest tensile strength of 24.3 MPa, tear strength of 62.2 N/mm and thermal denaturation temperature (Td) of 95.4 °C. The fogging values of the fatliquored leather satisfy the requirements of automobile seat leather. The biochemical oxygen demand (BOD5) and chemical oxygen demand results indicate that the DNC/AEJO-AA emulsion is easily biodegradable. Overall, the developed DNC/AEJO-AA emulsion provides a new strategy in the production of bio-based and ecological polymer fatliquor of leather.

A novel eco-friendly imidazole ionic liquids based amphoteric polymers for high performance fatliquoring in chromium-free tanned leather production

The potential environmental pollution of chrome tanned leather results in the development of ecological chromium-free leather tanning production in leather industry. However, with weakly positive charge, chromium-free tanned leather cannot strongly bind to anionic dyes, thus causing low quality of finished leather. Herein, p(DM-co-[DDVIM]Br)PS was synthesized by free radical polymerization method. The structure and properties of the targeted products were synthetically characterized. The results indicated that the use of p(DM-co-[DDVIM]Br)PS fatliquoring agent can not only make leather fibers become loose, but also improve the binding affinity between leather and anionic dye during the fatliquoring process. The fatliquoring agent adsorption rates and the dye absorption rate of the leather were as high as 99.26% and 99.01%, respectively; the fatliquoring and dye solutions were clear, so they can be used as clean materials in the fatliquoring process of chromium-free tanned leather. Leather treated with p(DM-co-[DDVIM]Br)PS fatliquoring agent had higher K/S value (12.80) and is softer than those treated with commercial fatliquoring agent. Consequently, this study can not only help improve the absorption rate of anionic wet finishing materials, but also reduce the pollution caused by chrome tanning agents, thus providing a new way for the cleaner production in leather industry.

Synthesis of Fat Liquor Through Fish Waste Valorization, Characterization and Applications in Tannery Industry

This study explores the feasibility of fish waste as the potential source of fish oil, which could be used as fatliquoring agent in leather processing. The fish oil was extracted from fish waste with a yield of 39.8 g/1000 g of sample on wet basis and converted into fatliquor by a sulphation process using sulphuric acid. The average particle size and particle dispersion index (PDI) of the fish oil fatliquor were determined to be 82.4 nm and 0.508, respectively, which implied that the fish oil fatliquor could penetrate the leather easily. Fish oil fat liquor emulsions prepared with water in 1:9 dilutions showed good stability after 24 h. Scanning electron microscope (SEM) analysis revealed that leather processed with the fish oil fatliquor exhibited a soft grain without any fatty-spew, which demonstrated easy penetration into the inner fibers of leather. The physical and mechanical properties of the leather lubricated with the sulphated fish oil fat were better than those processed using the commercial fatliquoring agent. It was also observed that pollution load such as chemical and biochemical oxygen demand of effluent from the fatliqouring process reduced significantly. This implied that the sulphated fatliquor derived from fish waste would be an eco-friendly alternative to traditional fatliquors used in tanneries.

Dissymmetry Gemini Sulfosuccinate Surfactant from Vegetable Oil: A Kind of Environmentally Friendly Fatliquoring Agent in the Leather Industry

Compared with surfactants synthesized from petrochemicals, those synthesized from vegetable oil have outstanding environmental friendliness and superior surface activity. Dissymmetric gemini surfactants, a new class of gemini surfactant, have superior properties. Dissymmetry gemini sulfosuccinate surfactant (DGSS) was synthesized from vegetable oil. The structure of the product was confirmed by Fourier transform infrared (FT-IR) and nuclear magnetic resonance (NMR) analyses. The properties tests of DGSS showed that the DGSS can significantly reduce the surface tension and has good emulsification ability, good wetting ability, and poor foaming performance. DGSS was applied as a fatliquoring agent in leather for lubricating collagen fibers and improving physical and mechanical properties of leather. Compared with leather treated with 14 wt % commercial fatliquoring agent, leather treated with 8 wt % DGSS can reach the same fatliquor effect. The biochemical oxygen demand (BOD5) per chemical oxygen demand (CO...

Bioremediation of synthetic fatliquors under microaerobic condition.

Synthetic fatliquors are useful as a fatliquoring agent, flotation agent and emulsifying agent in a wide range of industrial applications such as leather, pharmacy and farm chemicals. These fatliquors remain recalcitrant to natural biota in existing treatment plants. In the present study, the isolated microaerophilic Serratia sp. HA1 strain CSMB3 is capable of utilizing structurally different fatliquors as the sole substrate for their growth under microaerobic conditions. Degradation of vegetable fatliquors was observed from 95 to 97% in terms of lipids, with the production of lipase at 72 h. Degradation of synthetic fatliquors was observed in terms of chemical oxygen demand from 85% to a minimum of 25%. It is in the order of sulfited/sulfated fatliquors > sulfochlorinated fatliquors > chlorinated fatliquors. A thin layer chromatography chromatogram confirmed the degradation of non polar fatliquor to polar compounds. Production of the red pigment prodigiosin in synthetic fatliquors enhanced the growth of the isolate. Fourier transform infrared spectroscopy (FTIR) confirmed the bioremediation of sulfochlorinated fatliquor into lipids and fatty acids and gas chromatography-mass spectrometry (GC-MS) results confirmed that alcohols and esters are the final end products. Thus the isolated strain CSMB3 may be used in the treatment of wastewaters containing vegetable and synthetic fatliquors.

Preparation and application of castor oil/nano-TiO2 composite fatliquoring agent via a Pickering emulsion method

Castor oil in water emulsions known as fatliquors is used for the lubrication of tanned leather fibers to get softness and also to improve the strength properties. Fatliquoring agents are usually obtained by chemical modification. In this research, fatliquoring agent based on castor oil was prepared using nano-TiO2 as emulsifying agent by mechanical mixing. So castor oil/nano-TiO2 composite fatliquoring agent (CTF) was obtained via Pickering emulsion method. The presence of nano-TiO2 resulted in a stable emulsion. The results of transmission electron microscope showed that the castor oil was surrounded by nano-TiO2. Finally, CTF was applied in the leather fatliquoring process of goatskin garment. Physical and mechanical properties of leather fatliquored by CTF were improved compared with those of leather fatliquored by sulfated castor oil. CTF was easily biodegradable as compared to modified castor oil fatliquoring agent. Composite fatliquoring agent leads to reduction of many chemicals utilized to get the lightfastness of leather for adding nano-TiO2.

The Application of Epichlorohydrin-Dimethylamine Polymer Flocculant for Tannery Wastewater Treatment

A cationic organic flocculant epichlorohydrin-dimethylamine(EPI-DMA) was employed for the treatment of simulated leather-making process wastewater. The study aims at investigating the flocculation performance of EPI-DMA for the leather dyeing wastewater which contains fat-liquoring agent wastewater and retanning agent wastewater. The results show that decoloration efficiency of EPI-DMA for dyeing wastewater can reach around 90% with proper dosage. For containing retanning agent wastewater, EPI-DMA also has good flocculation performance, but for containing fat-liquoring agent wastewater, flocculation performance of EPI-DMA was poor.

Influence of Flame Retardant on Leather Fatliquoring and Fire Resistance

Commercial nitrogen-phosphorus flame retardants (KZR-2, SC-968, FR-102), which are frequently used in textile industry, were imposed on the fatliquoring processes of leather. When 0%, 0.5%, 1.0%, 1.5%, 2.0%, 3%, 6%, 9%, 12﹪and 15﹪ amount of flame retardants was respectively added, their influence on the absorption rate of different fatliquoring agents (synthetic oil, fish oil, vegetable oil and lecithin) and on the flame retardant property were investigated. The absorption rate of fat-liquoring agents was measured by oven and dichloromethane methods. The fire resistance was studied by means of oxygen index, vertical combustion and smoke density. The results show that flame retardants (KZR-2, SC-968 and FR-102) can enhance the absorption rate of fat-liquoring agents in leather by more than 40%. Their ability for this enhancement can be listed as KZR-2>SC-968>FR-102. Among them, KZR-2 owns the best performance for the enhancing of absorption rate ( its influence on the oil is listed as synthetic oil>fish oil>lecithin>vegetable oil).

Production of Ethoxylated Fatty Acids Derived From Jatropha Non-Edible Oil As a Nonionic Fat-Liquoring Agent

Natural fatty derivatives (oleochemicals) have been used as intermediate materials in several industries replacing the harmful and expensive petrochemicals. Fatty ethoxylates are one of these natural fatty derivatives. In the present work Jatropha fatty acids were derived from the non edible Jatropha oil and used as the fat source precursor. The ethoxylation process was carried out on the derived fatty acids using a conventional cheap catalyst (K₂CO₃) in order to obtain economically and naturally valuable non-ionic surfactants. Ethoxylation reaction was proceeded using ethylene oxide gas in the presence of 1 or 2% K₂CO₃ catalyst at 120 and 145°C for 5, 8 and 12 hours. The prepared products were evaluated for their chemical and physical properties as well as its application as non- ionic fat-liquoring agents in leather industry. The obtained results showed that the number of ethylene oxide groups introduced in the fatty acids as well as their EO% increased as the temperature and time of the reaction increased. The highest ethoxylation number was obtained at 145°C for 8 hr. Also, the prepared ethoxylated products were found to be effective fat-liquors with high HLB values giving stable oil in water emulsions. The fat-liquored leather led to an improvement in its mechanical properties such as tensile strength and elongation at break. In addition, a significant enhancement in the texture of the treated leather by the prepared fat-liquors as indicated from the scanning electron microscope (SEM) images was observed.

Synthesis and properties of modified rapeseed oil/montmorillonite nanocomposite fatliquoring agent

Modified rapeseed oil/montmorillonite (MRO/MMT) nanocomposite was prepared by using rapeseed oil, ethylene diamine, acrylic acid, and MMT. In order to compare MRO/MMT with MRO and a market product XQ-F3, they were applied in leather fatliquoring process, respectively. Sensory evaluation, physical and mechanical properties, and flame-retardant property of leather treated with different fatliquoring agents were measured. X-ray diffraction (XRD) results showed that MRO could smoothly enter the interlayer of MMT. The emulsifying property of MRO/MMT was confirmed better than that of MRO. The application results also showed that MRO/MMT has good fatliquoring effect. Meanwhile, it can increase leather strength and improve leather flame-retardant performance.

Highly Stable Nonionic Fatliquors Based on Ethoxylated Overused Vegetable Oils

AbstractOverused vegetable oils, which are considered to be a waste and available in huge quantities after frying processes, were directly ethoxylated using a conventional cheap catalyst in order to obtain an economically valuable ethoxylated product to replace the imported intermediate derivatives and at the same time the environment will be rid of one of its pollutants. Therefore, this work was devoted to exploring its application as a fatliquoring agent in the leather industry. Overused sunflower and olein oils were directly ethoxylated using ethylene oxide gas in the presence of 3% KOH catalyst at 180 °C for 20 h. The prepared products were applied as nonionic fatliquors. The fatliquoring process is the operation in which a fatty matter is introduced into the leather fibers. The results obtained showed that the prepared ethoxylated overused oils were effective fatliquors with high HLB values giving stable oil in water emulsion as well as high stability against acid, alkali and different metallic salts. The fatliquored leather had improved mechanical properties such as tensile strength and elongation at break. In addition, a significant enhancement of the texture of the treated leather by the two prepared fatliquors as indicated from the scanning electron microscope images was observed. Also the results indicated that ethoxylated overused sunflower oil gave better results than those of ethoxylated overused olein oil.

Recent Research Progress on Leather Fatliquoring Agents

In this paper, the types of the fatliquoring agents, the fatliquoring mechanism and the properties of fatliquored leather were introduced. Also, the recent research progress on leather fatliquoring agents were reviewed, and the prospects of leather fatliquoring agents were discussed.

Fatliquoring agent and drying temperature effects on leather properties

Leather, a collagen structure material, usually requires the addition of fatliquoring agents that have been recently found to cause instability during heating in critical manufacturing processes. The effect of fatliquoring agent concentration and drying temperature on the leather properties was investigated. Leather shrinkage, leather absorption of water and water vapour, and water vapour permeability were measured under defined conditions. The samples of bovine leather obtained after commercial liming and chrome tanning processes were used. The samples were fatliquored with 3, 6, 9 and 12% solutions of anionic synthetic fatliquoring agent and dried at different temperatures. The results of the investigation are corroborated by scanning electron microscope (SEM) study. It was shown how the concentration of fatliquoring agent and drying temperatures influence the leather properties.