Ammonia → Acrylamide-acrylic acid resin

Participants

Reaction Conditions

Reaction Steps

148 g of acrylic acid, 372 g of acrylamide solution (40%), 0.6 g of methylenebisacrylamide, and 1.2 g of triallylamine were initially dissolved in 260 g of water in a polymerization vessel. Thereafter, the monomer solution was neutralized with 126 g of ammonia (25%) to a neutralization level of 90%. The monomer solution then was cooled to 10° C. and purged with nitrogen. Following addition of the initiator solutions (0.8 g of ABAH, 1.0 g of sodium peroxodisulfate, 0.2 g of hydrogen peroxide, and 0.05 g of ascorbic acid, each in 5 ml of water), the polymerization was initiated. The maximum temperature of 100° C. was reached within 10 minutes. After completed polymerization, the polymer was heated at 140° C. for 1.5 hours and milled to the desired grain fraction. A crosslinked acrylic acid/acrylamide copolymer as ammonium salt had been formed. The absorptive capacity for a 0.1% fertilizer solution was 132 ml/g, and the residual monomer content was 10 ppm of acrylamide and 25 ppm of acrylic acid.

Provenance & Evidence