Fibers, charging

In addition to abrasion, triboelectric charging is a serious problem in the production and processing of synthetic fibers. Charged fibers, because of interfiber repulsion, do not form a coherent yam, and it is difficult to wind such yams on bobbins to be transferred to other locations for further processing. To overcome these problems, combinations of oils, fats, and their derivatives are used extensively as... 

Idg xiose. A Silesian blasting powder made of woody fiber charged with nitro-glycerine. 

Lyytikainen K, Saukkonen E, Kajanto I, Kayhko J. The effect of hemicellulose extraction on fiber charge properties and retention behavior of kraft pulp fibers. BioResources 2011 6(1) 219-31. 

Cellulose fibers suspended in water have the natural tendency to aggregate and create structures called floes. Flocculation effect affects several technological operations during paper production (especially paper web forming process). There are many factors that determine the effect of flocculation including fibers concentration, level of turbulence and fibers charge. 

The protonated form of poly(vinyl amine) (PVAm—HCl) has two advantages over many cationic polymers high cationic charge densities are possible and the pendent primary amines have high reactivity. It has been appHed in water treatment, paper making, and textiles (qv). The protonated forms modified with low molecular weight aldehydes are usehil as fines and filler retention agents and are in use with recycled fibers. As with all new products, unexpected appHcations, such as in clear antiperspirants, have been found. It is usehil in many metal complexation appHcations (49). 

Electrical Behavior. The resistivity of acetate varies significantly with humidity with typical values ranging from 10 ohm-cm at 45% rh to 10 ohm-cm at 95% rh (16). Because of the high resistivity both acetate and triacetate yams readily develop static charges and an antistatic finish is usually apphed to aid in fiber processing. Both yams have also been used for electrical insulation after lubricants and other finishing agents are removed. 

Flame-Retardant Treatments For Wool. Although wool is regarded as a naturally flame-resistant fiber, for certain appHcations, such as use in aircraft, it is necessary to meet more stringent requirements. The Zirpro process, developed for this purpose (122,123), is based on the exhaustion of negatively charged zirconium and titanium complexes on wool fiber under acidic conditions. Specific agents used for this purpose are potassium hexafluoro zirconate [16923-95-8] [16923-95-8] K ZrF, and potassium hexafluoro titanate [16919-27-0], K TiF. Various modifications of this process have been... 

Aluminum resinate particles, ie, size precipitate, are attracted to the fiber surfaces because of a difference in charge and thus are retained (45,46,54). In general, the particles of size precipitate are small and are distributed fairly uniformly over the sheet. However, on drying, there is some sintering of the particles which helps to redistribute them on the fibers. 

The cationic acrylamide polymers may contain either tertiary amine or quaternary ammonium groups. Because of their positive charge, they are self-retaining on pulp fibers therefore, they can be used effectively in nonalum systems. 

Antistats such as polyoxyethylenes (151,152) and A/-alkyl polycarbonamide (153) are added to nylon to reduce static charge and improve moisture transport and soil release in fabrics. These additives also alter the luster of fiber spun from bright polymer. Static reduction in carpets is achieved primarily by the use of fibers modified with conductive carbon black (see Antistatic agents Carbon, carbon black). 

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