Cellulose acetate nonwovens

Thus, two alternative methods were further applied for cotton/cellulose acetate nonwovens [25]. Water dip-nip treatment was further used instead of acetone solvent pre-treatment to make the process more enviromnent friendly. Comparing the effect of water dip-nip treatment with acetone solvent treatment, it can be found that there is no significant difference between water dip-nip treatment and 20% acetone solvent treatment and peak load of cotton/cellulose acetate thermally bonded webs are enhanced by both the treatments. Based on these data, water can be used as an external plasticizer instead of 20% acetone solvent without compromising web strength and the process is environment friendly. 

Suh, H., Duckett, K.E. and Bhat, G.S., Biodegradable and Tensile Properties of Cotton/Cellulose Acetate Nonwovens , Textile Research Journal, 66 (4), 230-237... 

Duckett, K.E., Bhat, G.S., Giao, X. and Haoming, R., Characterization of Cotton/ Cellulose Acetate Nonwovens of Untreated and Aqueous Pretreated Webs prior to Thermal Bonding , Proceedings of the INTC 2000. 

The white cell adsorption filter layer is typically of a nonwoven fiber design. The biomaterials of the fiber media are surface modified to obtain an optimal avidity and selectivity for the different blood cells. Materials used include polyesters, eg, poly(ethylene terephthalate) and poly(butylene terephthalate), cellulose acetate, methacrylate, polyamides, and polyacrylonitrile. Filter materials are not cell specific and do not provide for specific filtration of lymphocytes out of the blood product rather than all leukocytes. 

Other large volume applications for cellulose acetate fibers are filament yarns for ribbons for decorative packaging and tows for ink dispensers for felt tip pens. Cellulose acetate is used in nonwovens and in paper processes as staple and short-cut [87,88]. 

Cellulose acetate nanofibers reinforced with chopped polyaniline, PANI, nanoparticles were produced. PANI acts as a nucleating agent and increases the formation of crystallites. The overall degree of ciystalhzation is increased, leading to the increased number of dipoles in the nanofibrous nonwoven membranes. ... 

Natural fibers, such as cotton, kenaf, coir, jute, flax, sisal, hemp, and wood, etc., become the first choice due to their biodegradabihty. Some synthetic biodegradable fibers have also been used for nonwoven apphcations, including cellulose esters such as cellulose acetate, rayon, lyoceU, etc., polyesters such as poly(lactic acid) (PLA), poly(caprolactone) (PCL), poly(hydroxybutyrate) (PHB), poly(hydroxybutyrate-co-valerate) (PHBV), Biomax, Biopol, polytetramethylene adipate-co-terephthalate (PTAT), etc., and water solubles such as poly(vinyl alcohol) (PVA), etc. 

The desired calendering temperature of PCA bonded nonwovens is still much higher for achieving good tensile properties. So, a newly introduced biodegradable copolyester unicomponent (Eastar) fiber, which has a relatively low softening temperature ( 80°C), was further selected as a binder fiber instead of cellulose acetate fiber. It has been reported that this binder fiber... 

Superabsorbent polymer sheets have also been developed. If a particulate superabsorbent polymer is crosslinked between particles by a cationic polymer, for example, an amine-epichlorohydrin adduct, a superabsorbent polymer sheet can be prepared [23]. A particulate superabsorbent polymer, cellulose acetate and a plasticizer are dispersed in an appropriate solvent followed by casting onto a nonwoven cloth substrate. Upon irradiation by ultrasound, a superabsorbent sheet can also be prepared [24]. However, such material has poor compatibility with blood and lacks capillary channels. Thus, further improvement is necessary. Accordingly, various new superabsorbent polymers have been developed. Unfortunately, these polymers show insufficient property improvement or are too costly to be commercially available. 

Ex. 4. American Cyanamid supplies 10 Cyanabond textile adhesives which are described as nontoxic, water-based, 30 or 40% solids, prereacted, polyurethane emulsions that provide highly durable bonds when applied to woven, knitted, or nonwoven fabrics. They have an acetic acid-type odor. They may be used on a wide variety of cellulosic and synthetic textile substrates. When applied by established processing techniques they form bonds of cloth-to-cloth and foam-to-fabric that... 

Chitosan is the N-deacetylated form of chitin. The chemical formula of both is similar to that of cellulose and starch (see Figure 2). But unlike cellulose and chitin, chitosan is easily absorbed into the body and can be processed into many forms fibers, paper, nonwovens, and films. A film was cast for use in this project. In general, the chitosan powder was dissolved in acetic acid, and the mixture diluted with distilled water. The gel that developed was filtered and cast on a polycarbonate plate with a doctor s knife. After setting and drying at room temperature for 48 hours, the films were removed, neutralized in a methanol and sodium hydroxide solution, and then washed in distilled water. 

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