Hydrolysis of Poly(acrylamide) ‐ Starch Graft Copolymer

Abstract

Poly(acrylamide)‐starch graft copolymer was treated independently with sodium hydroxide and different acid solutions. The different acids include phosphoric, hydrochloric and sulphuric acid. The treatment was carried out under a variety of conditions including sodium hydroxide concentration, time and duration of hydrolysis as well as type of acid used. The extent of hydrolysis was assessed by estimating amide and carboxyl content as well as the acrylate and starch content before and after treatment. It was found that the increment in carboxyl content is equal to the decrement in amide on using sodium hydroxide concentration up to 1n, while using higher concentrations than 1n lead to differences in formed carboxyl and decreased amide groups. The magnitude of this difference depends on sodium hydroxide concentration as well as temperature and duration of hydrolysis. The maximum value of carboxyl content obtained was 593 m‐eq/100g sample. The acidic treatment of the starch copolymer does not affect the conversion of amide groups to carboxyl groups and the lonely effect was hydrolysis of starch component of the copolymer. Evaluation of the alkali teated copolymer as cation exchanger was carried out. The absorption efficiency % of different cations depends on the associated anions and follow the order: Cu2+ > Zn2+ > Co2+ Mg2+.

Synthesis of cotton-bearing DEAE, carbamoyethyl, carboxyethyl, and poly(acrylamide) graft for utilization in dye removal

“…Polymerization was allowed to proceed at 80°C for 60 min. At the end of reaction the sample was removed, thoroughly washed several times with cold and boiled water, and dried at 105°C for 180 min 11…”

Enhanced Removal of Methylene Blue and Methyl Violet Dyes from Aqueous Solution Using a Nanocomposite of Hydrolyzed Polyacrylamide Grafted Xanthan Gum and Incorporated Nanosilica

“…Khalil et al pointed out that the desired conversion of amide to carboxylic groups increases with NaOH concentration up to 0.1 (M) NaOH. 41 For higher concentrations, the side reactions compete significantly. 38 As expected, the NE values of partially hydrolyzed XG were found to depend on the NaOH concentration along with the time and temperature of the reaction.…”

Synthesis and characterization of starch‐graft‐polyacrylamide copolymers and their application as filtration control agents in drilling fluid

“…It is generally accepted that for the S‐g‐PAM macromolecule, hydroxyl groups and ether linkages of the polysaccharide portion, as well as amide groups of the PAM grafted chain, play the main role in the adsorption with clay particles, accompanied by a certain amount of hydration [20]. Also, the amide groups can be partly hydrolyzed in the alkaline drilling mud at certain temperatures and further converted into carboxyl groups with outstanding hydratability [21]. In addition, hydroxyl and amide groups due to their nonionic characteristic can endow the S‐g‐PAM with improved salinity tolerance [4].…”