Kinetics of swelling of cotton fibers in aqueous ethylenediamine solutions using moisture regain data

✍ Scribed by H. T. Lokhande; A. D. Pawar; S. R. Shukla; P. K. Chidambareswaran; N. B. Patil

• Publisher: John Wiley and Sons
• Year: 1983
• Tongue: English
• Weight: 407 KB
• Volume: 28
• Category: Article
• ISSN: 0021-8995
• DOI: 10.1002/app.1983.070280710

✦ Synopsis

Kinetic studies of swelling of cotton cellulose with 75% (w/w) EDA solution have been carried out. Three rates of the reaction were observed in the temperature range 10-35OC: first, the very fast rate ( k l ) lasting for about 10 s; second, the extremely slow rate ( k z ) lasting for 30-50 s; and third, once again a fast rate (k3), k l being faster than k3. k l was attributed to the swelling action of EDA-monohydrate in amorphous regions of cellulose; kz was assigned to the penetration of swelling species into crystallites accompanied by breakage of H bonds in these regions; and k 3 was assigned to the opening up of the crystallites. Activation energy values confirmed this trend. At higher temperatures (35-55OC), the middle rate kz merged with k3, giving only two rates, kl and k2+3, as the higher temperatures brought about simultaneous diffusion of swelling agent into, and decrystallization of, the crystalline portions of cellulose. EDA solution of 65% (w/w) concentration gave only two rates: the initial fast rate assigned to the swelling of the amorphous portion, followed by a slow one, operating in mesomorphous regions of cellulose, without any appreciable decrystallization. This was attributed to the important fact, viz., the absence of EDA-monohydrates in the solution.