Flocking

Beriberi, Thiamine Deficiency. The recognition of vitamins and their importance to the health of human beings came about when Eijkman, a Dutch pathologist, was sent to Java in an attempt to cure an epidemic of beriberi that had appeared in one of the hospitals. Eijkman kept a flock of chickens on the hospital grounds to assist in discovering the disease agent he assumed was involved in the etiology of beriberi. These chickens were fed the scraps from the plates of the hospital patients—primarily poHshed rice, the common food in that part of the world (11). 

The preparation of flocked fabric using acryflc adhesives is detailed in Reference 198. In flocking, cut fibers are bonded to an adhesive-coated fabric to achieve both a decorative and a functional effect. Acrylics can be tailored to provide the unique balance between softness and durability required for this... 

Steeping. Sheet, roU, or suitably milled flock pulp is metered into a pulper along with vigorously stirred 18% sodium hydroxide solution at 50°C. The resulting slurry, containing about 5% finely dispersed pulp, passes to a buffer tank from which it is metered to a slurry press that sieves out the swollen fiber and returns the pressings soda for concentration correction and reuse. The cellulose reacts with the soda as a complex alcohol to form the sodium salt or alk-ceU. 

Formic acid can also be used as an antisalmoneUa additive in animal feeds, for decontamination of feed raw materials, and prevention of flock infection in the poultry industry by treatment of the finished feed. 

Combinations of two or more of the above steps into consecutive processes, such as spin—draw or spin—draw—texture, reduces manufacturing costs. In addition to continuous-fHament yam, nylon is also offered in staple, tow, and flock forms. Staple is made by cutting crimped continuous-fHament yam into 3—20-cm lengths. In manufacturing, tow is made by combining many yam ends, either flat or crimped, to give a total tow size of 6—111 ktex. 

Flock is made by precision-cutting tow into 0.5—3-mm fiber lengths. 

Nylon is the preferred fiber for flocking because of its good chemical bonding to a wide range of adhesives, its toughness, and its ease of dyeabiHty and printabihty. Nevertheless, the tow must be manufactured with the proper ktex, cohesion, and spin finish to be readily converted to flock (133). 

Home furnishings, which is primarily dominated by cotton and polyester, includes drapes, curtains, bedding, table cloth, bathroom fabrics, and Upholstery. In the United States, nearly all of the nylon upholstery velours are flocked, printed fabrics. Nylon-flocked blankets are also made in the United States. 

Design with Flock in Mind, American Flock Association, Boston, Mass., 1992. 

Other Reinforcement Ma.teria.Is. Other materials that have been used in tire compounds for reinforcement are chopped wire (brass-coated), cotton and nylon flock, chopped nylon strands, polyethylene, zinc oxide, and chopped Kevlar. Most of these materials have very limited apphcation and some are obsolete. Others are used more extensively in soHd mbber industrial tires than in pneumatics. 

The 3-bromo-4-acetaminotoluene separates in crystalline flocks. It is filtered by suction and washed well with water and pressed dry. The wet crude material is dried until its weight does not exceed 500 g. before proceeding with the hydrolysis (Note 3). 

Self-curing butyl adhesives can be used for laminating polyethylene film and for flocking adhesives. One of the most important applications is the use of BR as curing, solvent-dispersed and contact-grade for roof manufacturing on industrial buildings. 

Applications for blocked urethane adhesives are small. However, they may be used as flocking adhesives or as crosslinkers for solvent-borne adhesives. Blocked urethane adhesives are also used as splicing adhesives for belts. Blocked isocyanates based on TDI, IPDI, and derivatives of hexamethylene diisocyanate are most commonly commercially available. 

Alum Astringent crystalline double sulfate of an alkali. K2SO4AL2 (S04)j 24H2O. Used in the processing of pickles and as a flocking agent. Excess aluminum in the environment can be hazardous. 

For Sm, Eu, and Yb, on the other hand, nanocapsules containing carbides were not found in the cathode deposit by either TEM or XRD. To see where these elements went, the soot particles deposited on the walls of the reaction chamber was investigated for Sm. XRD of the soot produced from Sm203/C composite anodes showed the presence of oxide (Sm203) and a small amount of carbide (SmC2). TEM, on the other hand, revealed that Sm oxides were naked, while Sm carbides were embedded in flocks of amorphous carbon[12J. The size of these compound particles was in a range from 10 to 50 nm. However, no polyhedral nanocapsules encaging Sm carbides were found so far. 

The values given in tlie first column are tliose of Flock (1955) and in die second colunm diose of die HSE (1965 HSW). Tlie values quoted from Flock are for initial pressure (atmospheric) and inidal temperature (room temperature) and in most cases dry gas and generally are selected from several values listed. 

Some higher values are also listed by Flock. 

M. Becke-Goehring and E. Flock, Chap. 3 in C. B. Colburn (ed.), Developments in Inorganic Nitrogen Chemistry, Vol. 1, pp. 150-240, Elsevier, Amsterdam, 1966. 

F. Hiibenett, F. H. Flock, and H. Hofmann, Angew. Chem. Intern. Ed. Engl. 

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