The Conversion Of Functional Groups Of Water-soluble Polymers

As the two kinds of extremely important water-soluble polymers, both maleic anhydride (PMA) and polyacrylamide (PAM) play a very impotant role in many industries for its special molecular structure. Because of the anhydride structure,PMA could be used to get low-DP surfactant by reacting with fatty alcohol, to get PMAO by reacting with octadecanol,and to get Protons-To-Body by reaction with [6-4-(octyloxy phenoxy)]-1-hexanol; Beacause of the amide groups in the molecular chain, PAM could be used to get hydrolysis polyacrylic acid,to get hydroxyl methylation polyacrylamide, to get sulfomethylated polyacrylamide,to get dimethylamino-N-Methylacrylamide by Mannish reaction, to get poly-(acrylamide-Co-vinylamine) by Hoffmann reaction,and so on.In this paper,we chose maleic anhydride as raw material.Firstly,we got the amidation product by inputing ammonia gas, making sure the amidation degrees is 49.4% by kieldahl method. Using formaldehyde as hydroxyl methylated reagent for the next reaction, and tow peaks are found out,respectively in the pH 9-10and 7-8.When pH is 9-10, the best condition is:the reactant ratio of formaldehyde and PMA is 1.5:1, reaction temperature is 50℃, reaction time is three hours, and the hydroxyl methylated degree is 130.8%;When pH is 7-8,that is 100.5%.The reason why hydroxyl methylated degree more than 100% is the hydroxyl methylated reaction not only at amide base but also at the macromolecular chain.The reaction of PAM with formaldehyde was researched in this paper. The effects of temperature, pH, time and reactant ratio were studied and the structure of product was characterized by FT-IR and 1H NMR. Using the method of sodium sulfite to measure the degree of methylation, and in the best condition,about 88.3% hydroxyl methylation degrees can be reached. If continue to improve the reactant ratio of formaldehyde, product hydroxyl methylation degrees can increase to 90%.The hydrolysis reaction of PAM was also studied in this paper,and the optimum reaction conditions was found out:the solution concentration of reactant solution(PAM) is lmol/L, the reactant ratio of PAM and NaOH is 1:1, the reaction temperature is 80℃, and the reaction time is three hours.In such condition,the hydrolysis degree of product is 45.4%.