Preparation And Properties Of Amphoteric Of Fatliquor Based On FTE

In the leather industry,in order to promote the development of chromless/chrome free tanning,it is necessary to develop amphoteric wet finishing materials for matching with organic tannage,so that the bonding force can be enhance between the following meterials and onganic tanning leather.In this study,a noval amphoteric fatliquor was prepared based on fatty triethanolamine ester?FTE?.Several of FTE were synthesized with fatty acid and triethanolamine in different molar ratio.The esterification rates of fatty acid were determined by acid value and saponification value.Fatty triethanolamine monoester?FTME?,fatty triethanolamine diester?FTDE?and fatty triethanolamine triester?FTTE?were separated through column chromatography and the structures were identified by FTIR and ¹H NMR.The results show that the esterification rates are from 94.3%to 97.4%in the condition of 180?for 6 hours under the nitrogen protection,using phosphinic acid as catalyzer?0.5%of mass of fatty acid?.Fatty acid triethanolamine monoester sulfosuccinate?FTMS?and fatty acid triethanolamine diester sulfosuccinate?FTDS?,based on FTME and FTDE respectively,were synthesized by esterification with maleic anhydride and sulfonation with sodium sulfite?The samples of FTMS are named as FTMS-1,FTMS-2,FTMS-3 and FTMS-4,which are obtained basing on lauric acid,palmic acid,stearic acid and oleic acid respectively;the samples of FTDS are named as FTDS-1,FTDS-2,FTDS-3 and FTDS-4,which are obtained basing on lauric acid,palmic acid,stearic acid and oleic acid respectively?.The structures of FTME and FTDE were identified by FTIR.The amphoteric structures were tested by methylene blue test and bromophenol blue test.The effect of chain length and unsaturation were explored on surface tension,Krafft point,particle size and emulsifying capacity.The results show that FTMS and FTDS both are amphoteric.As for FTMS,Krafft point and Z-average increases with the increase of the chain length of alkyl,however,the unsaturation of alkyl is conducive to decrease Krafft point and Z-average.FTDS have similar rules,however,the hydrophilia of FTDS are reduced comparing with FTMS,the influence of chain length and unsaturation on particle size is reduce.Especially,FTMS-1 and FTDS-1 have the great surfactivity;critical micelle concentration?CMC?are 52.97 mg/L and 93.95 mg/L and the?_CMC are 36.1 mN/m and 30.3 mN/m,respectively.The emulsifying capacity of FTMS-1?separation time:148.8 s?is similar to AEO-9?separation time:139.0 s?.Moreover,the emulsifying capacity of FTMS-1 is better than sodium dodecyl sulfate?separation time:113.8 s?.The emulsifying capacity of FTDS-1?separation time:159.2 s?is better than AEO-9 and sodium dodecyl sulfate.Fatty acid triethanolamine amphoteric fatliquors?FATF?were prepared,based on FTE,by esterification with maleic anhydride and sulfonation with sodium sulfite.The residue of sulfite in FATF,the emulsifying capacity and the isoelectric point of FTAF were measured.FTAF were used in fatliquoring experiment and study in the change of chain length and molar ratio effect on the fatliquoring performances.The performance differences of FATF were compared by K/S value,water vapor permeability,softness and physical and mechanical properities of curst leather,and the dye-uptake and the degree of dye penetration in the fatliquoring.The results show that the sulfite content?counted by SO₂?in FTAF is less than 5 mg/g.The isoelectric point of FTAF are 2.5⁴.3.In addition,FATF have excellent levelling property.FTAF based on palmitic acid and stearic acid,which the molar ratio of fatty acid and triethanolamine is 1.0 to 1.0,have the great dyeing accelerating property,comparing with sulfonated castor oil and semi synthetic oil,that K/S value have increased by 1.312 and 5.025,respectively,and show up the excellent emulsifying capacity.The softness,tensile strength and the tear strength of crust leathers are little different from common anionic fatliquor.FTAF has not much effect on water vapor permeability and dry rubbing color retention,but wet rubbing color retention has been improved obviously.