Studies On Sulfomethylation Of Biphenol A And Its Condensated Product

This paper reveaIs a new synthetic tanning agent for leather making.The product is obtained by condens ing, sulfomethylat ing and neutral izi nga mixture of bipheno1 A, formaldehyde and sodium metabisu1fite.The mechani sm of sulfomethy1ation is analyzed by UV----spectra,IR----spectra and viscosity, solubi 1i ty etc., the results show that thesulfomethylation of biphenol A can be divided into two parts, which isdifferent from the previous reports. Using orthogona1 experiment, theoptimal sulfomethy1ation recipe is determined by viscosity, solubi l ity,stabil ity in acid, surface tensi le and conductance, it is found out thatwhen the su1fomethylation was carried out at 80--85C, with 25% sodiummetabi sul fi te, l0% catalyzer, hi gher rat io of biphenol A to forma1 dehyde,the desirab1e product can be obtained. The compos it ion, molecu1ar weightof the su1fomethy1ated product is determined by GPC, e1ement ana1ysisetc. - The condensates are characteri zed by UV------spectra, IR------spectra and"C----NMR. The results show that the mo1ecular weight vary from 724 to 1500,the ratio of e1ement C:H:N:S:0 equa1s to 35:40:2:2: l1, then we get themo1ecular formula of the main components of the sulfomethy1ated product.The application experiment shows that it is a useful agent for 1eatherllmaking, with excellent lightfastness, which is suitable for producing light leather, good filling ability, nice grain. The resultant leather is very plump and soft. The product has strong affinity with chromium. The product can be applied for combination tannage with Fe2*, and decide the light color leather technology with Fe2* and the sulfomethylated products.