The Treatment of Wool with Aqueous Dispersions of Self-Crosslinking Polyacrylates

Self Cite

Several polyethylenes have been applied to wool from aqueous emulsions and from xylene solution. Resistance to felting shrinkage was found only when the polymer was cross-linked, even though the uncross-linked polymers were not necessarily removed on washing. Cross-linking was achieved either from reactive groups in the polymer chains or by the addition of a free-radical cross-linking agent such as benzoyl peroxide. Polyvinyl acetate behaved similarly to polyethylene, but polypropylene could not be cross-linked and did not shrinkproof.

Section: Discussionmentioning

confidence: 99%

Section: Polyethylene From Xylene Solutionmentioning

confidence: 99%

Treatment of Wool With Polyolefins

Feldtman

McPhee

Pratt

1967

Self Cite

“…However, it is well known that exhaust application is usually less efficient in conferring shrink resistance, attributed to the resin coverage of the fibers being less continuous. In first trying to apply the latex formulated above to woven bleached cloth by exhaustion, we were disappointed to find that none of the literature methods [7,8,[11][12][13][14] was applicable, nor was exhaustion in the presence of cetyltrimethylammonium bromide together with sodium sulfite [9]. Exhaustion occurred only in a bath at pH 1.6-2.4 using a strong acid at 80-85°C.…”

Section: Exhaust Applicationmentioning

confidence: 99%

“…In the current study, we describe an aqueous treatment in which the FWA is dissolved in the particles of a low temperature curing acrylic copolymer latex. Commercially available acrylic latexes are known to reduce shrinkage when applied to woven fabric by padding, followed by curing at 130° in the presence of an acid catalyst [5,[10][11][12]. Curing is usually due to crosslinking of N-hydroxymethyl groups.…”

mentioning

confidence: 99%

Surface Whitened, Shrink Resistant Wool Cloth of Improved Lightfastness

Levene

Kohanowski

Avichai

1991

An aqueous treatment has been developed for fully bleached woven wool cloth that combines surface whitening with resistance to shrinkage during washing. It is based on the surface application of a low temperature curing acrylic latex containing a fluorescent whitening agent. The copolymer of the latex contains groups capable of cross-. linking or of reacting with the wool protein. Surface whitening is achieved when the latex is applied by either padding or an exhaust process, but the latex is more effective in conferring shrink resistance when applied by padding.Though wool has unparalleled properties, it suffers from several disadvantages. One of these is its propensity to shrink and felt during washing. Two others are the poor lightfastness oj wool cloth, especially when wet or bleached, and the only moderate level of whiteness to which it can be bleached [8]. Together, these limit the range of pale shades the cloth can be dyed. Improved whiteness can be achieved by treating white or pale-shaded cloth with a fluorescent whitening agent (FWA) [15], but the FWA acts as a photosensitizer, accelerating the rate of photoyellowing, especially when the cloth is wet.While processes for machine washable wool garments, resistant to felt shrinkage, are well established [2, 6, 19], photoyellowing remains a problem. Since it is the UV component of sunlight that causes photoyellowing, its rate can be reduced by UV screening agents applied by exhaustion [6] or dissolved in a resin coating [10]. These cannot be applied together with fluorescent whiteners, however, because of fluorescent quenching. The acceleration of photoyellowing occurring in the presence of FWA can be prevented by physically removing it from close proximity to the wool protein by applying it in a resin coating (surface whitening) [20]. It is logical to try to combine surface whitening with a shrink resist process, since resin treatments for wool cloth are mostly for the latter purpose.In Part I of this series, we described surface whitening using an acrylic resin combined with a silicone-based resin used commercially for conferring shrink resistance, both applied in an organic solvent [16]. In the current study, we describe an aqueous treatment in which the FWA is dissolved in the particles of a low temperature curing acrylic copolymer latex. Commercially available acrylic latexes are known to reduce shrinkage when applied to woven fabric by padding, followed by curing at 130° in the presence of an acid catalyst [5,[10][11][12]. Curing is usually due to crosslinking of N-hydroxymethyl groups. Exhaust processes have been developed [5,13,14]. Water soluble acrylic copolymers containing reactive groups also confer shrink resistance [4]. An acrylic copolymer latex containing epoxy groups can be applied by padding or exhaustion, and crosslinking is with polyethylenimine at 150° [7]. High temperature curing causes yellowing and is not suitable for our purpose, but more recently Mehta [21 ] described the use of a low temperature curing cationic acrylic latex, appl...

“…These were done with 12-in. lengths of sliver in an agitator-type domestic washing machine [4] ' using a sodium borate solution (0.1 1 7c, ) -at 25 ° C. All samples were gilled three times prior to the felting test. The shrinkage figures given in the tables are the means of four separate determinations.°…”

Section: Introductionmentioning

confidence: 99%

The Variability of Wool Tops in Treatments with .Oxidative Shrink-Resist Reagents

Anderson

McPhee

1967

Self Cite

A wide variation in absolute shrinkage characteristics of wool tops is found after treatment with oxidative shrink-resist reagents under given sets of conditions. This is not related to the quality of the wool, and the response of any one batch of tops to shrink-resist treatment is unpredictable.At least two factors can cause these variations, one being the felting property of the original top and the other being the quantity of contaminant on the surface of the wool fibers. If the surface contamination is always reduced to 0.2% to 0.3% by prescouring the tops, then the same degree of shrink resistance, relative to the corresponding untreated top, is usually obtained for the given shrink-resist conditions. However, the absolute shrinkages, although often considerably better than those obtained on unscoured tops, can still vary over wide limits. '