| A new approach to adsorb and separate the protein of Natural Rubber Latex was investigated by using the reaction between the surface epoxy modified SiO2 and the amino-group of protein in this paper. It is known that the epoxy group could react with amino-group under basic condition, so a surface epoxy modified SiO2 was prepared and was used to treat NRL. After the reaction between the epoxy group and the amino-group, the protein of NRL was attached to the surface of SiO2. While the NRL was centrifuged to produce concentrated NRL, the SiO2 and the protein attached to the surface of SiO2 were separated from NRL.The results showed that, using toluene as a solvent,while the mass fraction of KH560 was in 51%,modification temperature was 110℃,the reaction time was about 8 hours, the lipophilic degree of modified SiO2 particle was 73.2%. FTIR spectrum indicated that KH560 was combined to the surface of SiO2 particle by chemical bond,and the epoxy group kept no change.The modified SiO2 particle could effectly adsorb and separate the proteide of natual rubber latex.The result showed that the nitrogen contents in natural rubber latex had come down from 0.4387% to 0.2293%, about 48% reducation,when the amount of modified SiO2 particle was 1%,treatment time was 6 hours,ammonia content was 0.3%, PH value was 8～9. At the same time, the FTIR spectrum of modified SiO2 particle after treating natural rubber latex appeared new characteristic absorption peak in 1577cm-1 and 1350cm-1,indicated the protein in natural rubber latex attached to the surface of modified SiO2 particle through chemical bond.The colloidal properties,the storage properties of treated concentration natural rubber latex and the mechanical properties of vulcanized films showed that the colloidal properties,the mechanical stability,the thermostability and viscosity had little difference comparing with contrasting NRL, but the modulus and aging property of vulcanized films were a little lower than the ontrasting NRL. |
PDF Full Text Request