Cellulose textile crosslinking

Soil Release. The modification of the physical properties of cellulosic textile products, particularly by crosslinking or treatment with polymeric... 

The reactant-type crosslinking agents have hardly any influence on the handle of cellulosic textiles, the only exceptions being FIXAPRET CPU and BU. On blends containing more than 50% of polyester fibres, FIXAPRET PEC and CPN produce the softest handle. 

FIXAPRET PCL can be applied to cellulosic textiles by all processes and for all finishes in which latent or potent acids are used as catalyst, e.g. classical finishing, moist cross-linking and wet crosslinking. It is the most versatile of all FIXAPRET types. FIXAPRET PCL is one of the less reactive cross-linking agents and must, therefore, be cured under energetic conditions. 

Figure 1 shows the repeating glucose units of cellulose with the carbons labeled, including those with the reactive 2, 3, and 6 hydroxyls. Ihe most important reactions of cotton cellulose commercially are esterification and etherification, with the products of etherification ranking first. It is generally agreed today among textile scientists that durable press cellulosic textiles ow their smooth-drying and resilient properties to the reactivity of formaldehyde and its amide derivatives with cellulose to produce crosslinks between adjacent cellulose chains (Figure 2). Hovever, the theory that crosslinking was responsible for increased resiliency developed only after the treatmaits were in wide use.

Crosslinking of cellulose, in heterogeneous systems, with formaldehyde or formaldehyde adducts of urea, melamine, or carbamates impart dimensional stability to cellulosic textile and paper products (Nicholson and Meritt 1985). A range of polymers, to obtain a better balance of properties for the commercial application of... 

The preparation of cellulose copolymers with vinyl monomers, which have functional groups that are hydrophilic in nature, has given textile products with improved soil release properties. For example, as shown in Figure 5, crosslinked cellulose-poly (methacrylic acid) copolymer fabrics exhibited both increased oily and aqueous soil release during washing compared with the crosslinked control fabrics. However, for oily soil, when softeners were added to the wash water, this improvement in soil release decreased. Crosslinked cellulose-poly (hydroxyethyl methacrylate) copolymer fabrics exhibited no improvement in oily soil release and only slight improvement in aqueous soil release compared... 

Reactive Derivatives. As with the polymeric carbohydrates, one method that might lead to future utilization of carbohydrates as adhesives involves the formation of reactive derivatives attached at the hydroxyls. This would give a component capable of crosslinking to form adhesive polymers. Here again,the adhesives chemist will have to borrow from and extend the work that has been and is now being done on the formation of modified starches, cellulosics, and textiles. 

Belmadur A process for strengthening wood by chemically crosslinking the cellulose fibers. This process enables relatively soft woods to be used in place of tropical hardwoods. The crosslinking agent is a complex polyol, similar to agents used for making textiles crease-resistant, hence the... 

Chemical finishing of textiles Table 5.1 Positive effects of cellulosic crosslinking finishes and corresponding... 

CNC FLEX 492 is a self-crosslinking acrylic emulsion whose air dried films are clear, hard and water resistant. CNC FLEX 492 is of particular interest in textile applications because of the very firm hand it imparts to cellulosic or synthetic fabrics. 

Uses Alkyd resins paints dynamite ester gums perfumery lubricants softener bacteriostat penetrant emollient antifreeze prod, of antibiotics plasticizer for regenerated cellulose film, sodium silicate foundry resins solvent (printing inks) humectant (tobacco, starch adhesives, textile sizes) solvent, humectant, plasticizer, bodying agent for foods, food pkg., cosmetics plasticizer, solvent, solubilizer, preservative for pharmaceuticals PU crosslinker heat costabilizer (PVC) sweetener preservative plasticizer in food-contact coatings Use Level 0.2-65.7% (topicals), 1-50% (liq. orals), 50% (parenterals), 7-10% (dentifrices), 0.5-3.0% (ophthalmics)... 

Textile fibers, in which a crystalline fibrillae are axially distributed in an amorphous crossiinked matrix are studied in Japan and the USSR. Fine long semicrystalline axially oriented PVC fibrils are contained in a crosslinked matrix of pol3Tvinylalcohol in the Cordelan fiber and fibrils of PAN are similarly distributed in a matrix of a wet spun natural protein in the Chinon fiber. In the USSR Rogowin is studying similar composite fiber systems on the basis of cellulose and its derivatives, together with vinylic and acrylic polymers. 

The intermolecular crosslinking of cellulose molecules in fibers that have been formed into paper and textile products has been of interest primarily in maintaining dimensional stabilities of the products. Crosslinking reactions of cellulose are conducted almost exclusively in heterogeneous systems. Crosslinking reactions include heat treatments, particularly for paper, and esterification and etherification reactions of bi- and tri-functional reagents, usually soluble in water, with cellulose. 

Uses Dispersant, dye leveling agent/retarder, emulsifier in textiles solvent for cellulose gelling inhibitor in polyester resins intermediate agric. chem. phase transfer catalyst accelerator in food-contact crosslinked polyesters Regulatory FDA 21CFR 177,2420 Canada DSL... 

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