ISSN:
0021-8995
Schlagwort(e):
Chemistry
;
Polymer and Materials Science
Quelle:
Wiley InterScience Backfile Collection 1832-2000
Thema:
Chemie und Pharmazie
,
Maschinenbau
,
Physik
Notizen:
With a sodium thiosulfate-potassium persulfate redox system, in situ polymerization of acrylonitrile was studied in cellulosic materials. Traces of copper are found to accelerate the rate of polymerization, giving higher yields on the treated materials. Other variables studied were (a) material/liquor ratios, (b) monomer concentrations, and (c) initiator concentrations. It is found that high material/liquor ratios and higher initiator concentrations cause increased polymer yields on cotton fabrics. Fabrics containing polyacrylonitrile (PAN) are resistant to microbial degradation. Acrylonitrile was polymerized in secondary cellulose acetate, mercerized cotton, and cellophane. Studies of the insolubility behavior of the treated cellulose acetate samples in acetone and dimethylformamide, and of mercerized cotton and cellophane in cuprammonium hydroxide, were carried out for the purpose of examining the presence of cellulose-PAN grafts. In the latter case, a constant ratio of cellulose to PAN was obtained in the cuprammonium hydroxide-insoluble fraction over a wide range of polymer add-ons. Alkaline saponification of the nitrile groups in the treated cotton fabrics, followed by a treatment with formaldehyde at pH 9-9.5 and subsequent curing in the presence of an acid catalyst, yield highly crosslinked fabrics which exhibit a considerable improvement in the wet crease recovery with slight loss in tensile and tear strengths. It is believed that these changes are brought about by the formation of a —CO · NH · CH2. O—cellulose type of crosslink. These results strongly support the presence of a cellulose-PAN graft.
Zusätzliches Material:
7 Ill.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1002/app.1963.070070502
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