ISSN:
0021-8995
Keywords:
Chemistry
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
,
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
,
Physics
Notes:
Acrylic acid (AA), acrylonitrile (AN), and acrylamide (AM) were grafted onto polyformaldehyde (PF) fibers employing γ-ray irradiation as well as benzoyl peroxide initiation. The nature of the graft copolymer obtained from a given monomer was dependent on the type of method used for the grafting reactions. This was reflected in the various characteristics of the grafted PF fibers such as moisture regain and dyeability to disperse, direct, basic, and acid dyes. The extent of grafting was dependent on time, concentration of the initiator, concentration of monomer, and irradiation dose. The grafting reaction with all the three monomers and both methods of grafting studied followed first-order kinetics. The rate constant values for grafting with AA, AN, and AM were 0.493, 0.576, and 0.420 hr-1, respectively for the irradiation method and 0.385, 0.385, and 0.346 hr-1, respectively, for the benzoyl peroxide initiation technique. The increase in the moisture regain was directly proportional to the amount of graft in the fiber. Acrylic acid grafted PF fibers were rendered hydrophilic to the highest extent (7.9% M.R. for 42% graft), while AM-grafted fibers were rendered so to the lowest extent (7.23% M.R. for 76.5% graft). Considerable improvement in dyeability of PF fibers was observed as a result of grafting. In general, dyeability was proportional to the amount of graft introduced in the fibers. The AA-grafted PF fibers gave a six-to sevenfold increase in disperse dye content when the irradiation method was followed and a four-to fivefold improvement when the chemical method was used during the grafting reaction. The AA-grafted and AM-grafted PF fibers show considerable affinity toward direct cotton dyes. The two substrates could also be dyed with fiber-reactive dyes in deep fast shades, the AM-grafted PF fibers giving deeper shades as a result of higher reactivity imparted to the substrate by the NH2 group of the graft copolymer. The AA- and AN-grafted PF fibers could be dyed in intense deep shades with cationic dyes. Similarly, AM-grafted substrates gave bright deep shades with acid dyes. Infrared studies, used to analyze the grafted PF fibers, indicated the presence of —COOH, —CN, and —NH2 groups introduced in the fiber structure as a result of grafting with AA, AN, and AM.
Additional Material:
14 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/app.1978.070220512
Permalink
