Synthesis And Performance Of Modified Rapeseed Oil/montmorillonite Nano-composite Fatliquoring Agent

Fatliquoring agent is one of the important leather chemicals with widelyapplications in leather industry, and can endow the leather with goodperformances. However, it can migrate easily to the surface of leather to becomefuel due to the low fixation between fatliquoring agent and collagen fibers. Thusit improves the flammability. Therefore, flame retardance has become one of therequirements of leather used in decorating of high building, aircraft and car,manufacturing of office furniture, fire-prevention equipment in forest. Thetraditional flame retardant leather is obtained through adding halogen-containingflame retardants. But the halogen could release a lot of smoke and toxic,corrosive hydrogen halide when flaming which could cause serious harm tohumans and environment. Therefore, green flame retardant has attracted muchconcern. The energy crisis caused by the limitation of non-renewable petroleumresource and environmental pollution during using force people to replacepetroleum with natural oils to process in-depth as chemical raw materials. On theother hand, our country has become a global oil country. Natural oils become themain raw material to prepare fatliquoring agent. Rapeseed oil is one of rawmaterials to prepare vegetable oil-based fatliquoring agent which is earliest usedand still in used.In our research, modified rapeseed oil （MRO） was prepared by usingrapeseed oil, ethylene diamine, acrylic acid and sodium bisulfite as raw material.Then modified rapeseed oil/Na-montmorillonite was prepared by ultrasonicmethod. On the other hand, modified montmorillonite was prepared usingquaternary ammonium salt （fatty acid, tanning ion or silane coupling agents） asmodifiers. Modified montmorillonite was characterized by XRD, FT-IR andTGA. Then modified rapeseed oil/modified montmorillonite by quaternary ammonium salt （fatty acid, tanning ion or silane coupling agents） nanocompositefatliquoring agent were synthesized by in-situ method. The stabilities ofnanocomposite fatliquoring agent were investigated and nanocompositefatliquoring agents were characterized using XRD, FT-IR, TGA and SEM, andapplied in fatliquoring process of goatskin garment leather. Physical andmechanical properties, flexibility and flame retardant property of leather usingnanocomposite as fatliquoring agent and the waste liquid after fatliquoringprocess were discussed. SEM and EDS were used to characterize the leather afterfatliquoring. At last, composite fatliquoring agent was prepared through mixingmodified rapeseed oil, vegetable oil and mineral oil. The performances ofleathers fatliquored by our product and similar foreign products as fatliquoringagent were compared.Synthetic process of modified rapeseed oil was optimized throughorthogonal experiment and single factor experiment. The optimal preparationconditions were: dosage of rapeseed oil was1mol, dosage of ethylene diaminewas0.6mol, dosage of acrylic acid was2.6mol, dosage of aluminum oxide was0.12mol, and dosage of sodium hydrogen sulfite was2.88mol. The FT-IR andUV results show that the modified rapeseed oil fatliquoring agent was preparedsuccessfully. Then MRO was applied in leather fatliquoring process. Comparedwith commercial product, the application results show that MRO has goodabsorption effect and could endow leather with better flexibility, fullness,flexibility.The optimum preparation condition of modified rapeseedoil/montmorillonite （MRO/Na-MMT） was investigated through the single factorexperiment and the orthogonal experiment. The optimal conditions were:ultrasonic power was700W （50g）, total ultrasonic time was35min, ultrasonicinterval time was2s/1s, and dosage of montmorillonite was7%. FT-IR, TEM andXRD results show that the modified rapeseed oil could smoothly into theinterlayer of montmorillonite and intercalation nano-meter composite wasobtained. Interlamellar spacing of MMT in nanocomposite increased and thendecreased. The modified rapeseed oil, MRO/Na-MMT and commercial productfatliquoring separately applied in leather fatliquoring process. The applicationresults show that MRO/MMT could improve the flame retardancy effectively, tensile strength and tear strength of leather and reduce plastic of crust leathercompared with MRO. Tensile strength, tear strength, flexibility, softness andfullness of leather fatliquoried by MRO/Na-MMT were better than that of leatherfatliquored with commercial product.Modified montmorillonite using quaternary ammonium salt with differentchain length as modifiers were prepared. FT-IR, XRD, TGA results show thatquaternary ammonium salt could enter into the interlayer of montmorillonite andmodify montmorillonite successfully. The modified montmorillonite byquaternary ammonium was introduced into the modified rapeseed oil by in-situmethod. FT-IR and XRD results show that MRO/quaternary ammoniumsalt-MMT nanocomposite fatliquoring agent was prepared successfully andlayers of MMT were existed in the form of stripping. Application results indicatethat softness, physical mechanical properties and flame retardant performance ofleather fatliquored by MRO/quaternary ammonium salt-MMT were improvedcomparing with that of leather fatliquored by MRO. The flame retardancy ofnanocomposite fatliquoring agent containing modified MMT by single-chain andthree-chain quaternary ammoniums were both better than that of nanocompositefatliquoring agent containing modified MMT by double-chain quaternaryammonium when the length of alkyl chains were equal. As the substitutionnumber of alkyl were equal, the flame retardancy was better with increasing thelength of alkyl in quaternary ammonium salt. Among them, the comprehensiveperformance of leather farliquored by MRO/trioctylphosphine methylammonium chloride-MMT nanocomposite fatliquoring agent was optimal.Modified MMT by a variety of fatty acid were prepared. FT-IR, XRD, TGAresults show that a serious of fatty acid could enter the interlayer of MMT andMMT was modified successfully. The nanocomposite fatliquoring agent wasobtained through introducing the modified MMT by a serious of fatty acid intomodified rapeseed oil by in-situ method. Stable nanocomposite fatliquoringagent containing stearic acid-MMT, cetylic acid-MMT or lauric acid-MMT couldnot be obtained. Application results show that softness, physical and mechanicalproperties of leather fatliquored by MRO/fatty acid-MMT were improvedcomparing with that of leather fatliquored by MRO. And flame retardancy ofleather was increased with increasing amount of MMT. Among them, the comprehensive performance of leather farliquored by MRO/oleic acid-MMTnanocomposite fatliquoring agent was optimal.Modified MMT by tanning ions was characterized by FT-IR, XRD andTGA. The result indicates that the best pH for reaction between Cr³⁺、Al³⁺、Fe³⁺、Zr⁴⁺and Na-montmorillonite were3.5,4.5,7.0,2.0, respectively. The interlayerspacing of various ions-MMT was1.55nm,1.54nm,1.53nm,1.43nm,respectively. The modified MMT by tanning ions were introduced into modifiedrapeseed oil by in-situ method. The results of FT-IR, XRD and TGA show thatMRO/tanning ions-MMT nanocomposite fatliquoring agent were preparedsuccessfully. Layers of MMT were existed in the form of stripping whendifferent amount of Al ion were utilized to prepare nanocomposite fatliquoringagent and the thermal stability of MRO/Al-MMT nanocomposite fatliquoringagent was the highest. Softness, physical and mechanical properties and flameretardant performance of leather fatliquored by MRO/tanning ions-MMT wereimproved compared with that of leather fatliquored by MRO.Different kinds of silane coupling agent were used to modify MMT. Theresults show that KH570，KH551，KH108and KH550could enter the interlayerof MMT. However, hexadecyltrimethoxysilane, dodecyltrimethoxysilane,KH560and A-151could not enter the interlayer of MMT. The silane couplingagent-MMT was introduced into the modified rapeseed oil by in-situ method.The results of FT-IR, XRD and TGA show that MRO/silane couplingagent-MMT nanocomposite fatliquoring agent was obtained successfully. Layersof MMT were existed in the form of stripping when the amount of silanecoupling agent-MMT was lower than2%. Application results show that softness,physical and mechanical properties and flame retardancty of leather fatliquoredby MRO/silane coupling agent-MMT were improved compared with that ofleather fatliquored by MRO. Among them, the comprehensive performance ofleather fatliquored by MRO/KH551-MMT nanocomposite fatliquoring agentwas optimal. The results of SEM and EDS show that the layers of MMT couldpenetrate effectively into or disperse uniformly into the collagen fiber withoutany changes on structure of fibers which make the loose of collagen fiberincreased.Composite fatliquoring agent was prepared through mixing MRO and vegetable oil, mineral oil. Application results show that softness and fullness offatliquored leather could be improved. Tensile strength, tear strength andelongation at break of leather were approximate to that of leather farliquored bysimilar commercial products. The MRO composite fatliquoring agent has alreadyput into industrial production through adjustment on process and raw materialand market effect is good.In this paper, functional leather fatliquoring agent was prepared usingmodified rapeseed oil as raw material, which could achieve the developmentneeds of the leather industry and improve the value in use of rapeseed oil inleather industry. The combination of traditional leather industry with theemerging nanotechnology and introduction of different modified montmorilloniteinto flame retardant modified rapeseed oil/MMT nanocomposite fatliquoringagent can not only satisfy the needs of people’s daily life, expand leatherapplication, but also has an important significance to development ofhalogen-free flame retardant leather chemical and sustainable development ofleather industry.