THE PREPARATION OF CELLULOSE ACRYLIC-ACETIC MIXED ACID ESTERS

Abstract

Various methods for the preparation of cellulose acrylic-acetic mixed acid esters were investigated.(1) Celluloses pretreated with 40% aqueous solution of CH3COOK or CH2=CHCOOK were treated with a mixture of CH3COOH, (CH3CO)2O, CH2=CHCOOH and a diluent at 120°C. Three to fourteen weight % of acrylic acid ester groups were introduced together with the acetic acid groups.(2) Celluloses were treated with a mixture of CH3COOH, (CH3CO)2O, CH2=CHCOOH, a diluent and H2SO4 as catalyst. No acrylic acid ester groups were found in the reaction product.(3) Cellulose di-or tri-acetates were hydrolyzed in 90-95% aqueous solution of CH2=CHCOOH with 0.1-0.5% HCl as catalyst. A small amount (ca. 2.6%) of acrylic acid ester groups were introduced.(4) Celluloses impregnated with 40% CH3COOK aqueous solution were treated with (CH2=CHCO)2O in a diluent. A large amount of acrylic acid ester groups (ca. 30%) were introduced.(5) Celluloses were treated with a mixture of (CH3CO)2O, CH3COOH, (CH2=CHCO)2O and CH2=CHCOOH with H2SO4 as catalyst. The mixed cellulose esters containing 10-20% of acrylic ester groups and 30-35% of acetic acid ester groups which are soluble in organic solvents were obtained.The IR spectra of pure cellulose acrylate were compared with those of cellulose acetate. The absorption bands of 1635, 1410, 1300, 1195, 980 and 807 cm-1 were observed in cellulose acrylate, while they were absent in the cellulose acetate. The absorption at 807 cm-1 was used as a qualitative characteristic measure for the presence of cellulose acrylate.