Mechanical and thermal properties of acrylic fibers crosslinked with disulfonyl azides

Abstract

ABSTRACT:A novel method for the crosslinking of acrylic fibers was devised, which uses disulfonyl azides as crosslinking agents. This is a fiber-finishing process in which 1,6-hexanedisulfonyl azide, 1,3-benzenedisulfonyl azide, 4,4-biphenyldisulfonyl azide, 1,5-naphthalenedisulfonyl azide, and 2,6-naphthalenedisulfonyl azide were applied to an acrylic fiber (Courtelle) and thermally treated to bring about crosslinking. A study was made of the mechanical and thermal properties of the crosslinked fibers and of the abrasion and pilling performance of the associated fabrics. Crosslinking brought about significant improvements in the initial modulus, resistance to abrasion, pilling performance, and thermal stability of the fibers.

Thermomechanical and creep properties of poly(ethylene terephthalate) fibers crosslinked with disulfonyl azides

“…The traces for the samples treated with 1,6‐HDSA were, by contrast, only slightly different from those of the standard sample. This result is in line with the smaller changes noted in the mechanical properties of the 1,6‐HDSA‐treated samples, discussed in our previous publication 1. Again, this was interpreted to be due to a more uniform distribution of crosslinks rather than less reaction.…”

“…Figure 2 shows the relative effects of using the different azides at the same concentration: 2,6‐NDSA appeared to be slightly more effective than 1,3‐BDSA, whereas the 1,6‐HDSA‐treated sample was barely distinguishable from the standard. We argued earlier1 that the differences between the two aromatic azides might reflect the greater extent of diffusion of 2,6‐NDSA into the fiber.…”

“…Two different levels of loading were also applied; in one case, the total mass was 75 g, that is, approximately 12% of the breaking load of the standard sample at 20°C, within the Hookean region of the stress-strain curve of the standard sample. 1 The higher level of loading used was 150 g (24.5% of the breaking load and just outside the Hookean region of the standard sample). The machine was allowed to reach the starting temperature at which the sample was mounted; the machine was then allowed to run with the load applied after the data recording had begun.…”

“…We recently described studies of the crosslinking of acrylic fibers1 and poly(ethylene terephthalate) (PET) fibers2 with disulfonyl azides. Although the acrylic fibers could be crosslinked sufficiently to maintain their fiber form in dimethylformamide, the partially oriented Dacron yarn always disintegrated in o ‐chlorophenol.…”

Cross-linking and modification of saturated elastomers using functionalized azides

“…Generally, sulfonyl azides are preferred over azidoformates due to their higher decomposition temperature which allows for melt mixing with thermoplastics. [60][61][62][63][64][65][66][67][68][69][70] It has been shown that di-sulfonyl azides are able to effectively crosslink polyethylene as well as polypropylene. Moreover, no signs of formation of low molecular species after PP treatment suggest that free radical reactions are negligible.…”