ISSN:
0021-8995
Schlagwort(e):
Chemistry
;
Polymer and Materials Science
Quelle:
Wiley InterScience Backfile Collection 1832-2000
Thema:
Chemie und Pharmazie
,
Maschinenbau
,
Physik
Notizen:
Blends of nylon 6 with poly(acrylic acid) polyacrylamide, poly(ethylene-co-acrylic acid), poly(ethylene-co-vinyl alcohol), poly(acrylamide-co-acrylic acid), and polypropylene were prepared by melt blending. Annealing treatments included treatments in Vacuum, in water, and in 20% formic acid at various temperatures. WAXS (wide-angle X-ray scattering) patterns of melt chips and of undrawn, drawn and textured yarns were obtained. The melt chips of 100% nylon 6 crystallize in the α form while the chips of all the blends exhibit a single diffracton ring. All the blends behave similarly during different annealing treatments. When annealed in 20% formic acid at 102°C, the α structure results. The as-spun fibers of nylon 6 and of the blends with poly(acrylamide-co-acrylic acid) and poly(ethylene-co-vinyl alcohol) exhibit a broad diffraction maximum in the region 2θ = 19-25°. The α content and its purity increase with increasing severity of the annealing treatment. The as-spun fibers of the blend with poly(acrylic acid), on the other hand, exhibit a highly oriented γ structure which is highly resistant to conversion to the α from during the annealing treatments. Only when treated in 20% formic acid at 102° does the pure α form result. The drawn textured yarns of nylon 6 exhibit both the α and the γ forms. However, the γ content of the textured yarns from the blends varies with the type and concentration of the additives. The textured yarns from the blends with low levels (0.125%) of poly(acrylic acid) have a very high α content. It is very unusual that the as-spun fibers with almost pure γ structure, when drawn, produce a structure with a high α content.
Zusätzliches Material:
14 Ill.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1002/app.1983.070280711
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