Fiber Cohesiveness

Three forms of set may be conferred to wool fibers. (/) Cohesive set is imparted when the fibers are dried under strain or set in steam and is lost when the fibers are relaxed in water at room temperature. (2) Temporary set is imparted at higher temperatures and is lost when the fibers are wet out in hot (70°C) water. (2) Permanent set is imparted in boiling water and in high pressure steam, and is stable to release in hot water. 

BANDAGE ELAS 4"X5YDS STER NONWVN W/ELAS FIBERS COHESIVE MATL 18S 6510013549509 PG 51,31 ... 

Interfiber friction is important in the development of staple fiber yarn strength, in the amount of energy needed during the opening process, in ensuring that there is sufficient fiber cohesion to hold together the web at the card, in all the drafting processes, whether... 

ASTM D 2612-93a provides a method for measuring the fiber cohesion force required to cause initial separation of fibers in a bundle of fibers. This observed cohesive force is converted to cohesive tenacity based on the linear density of the fiber specimen. The method is not advi,sed for trade purposes but as an in-house quality check, since the coefficient of variation of the test using man-made fibers is in the region of 21%. or 15% with a single operator. The ASTM method advises the conditioning of the test sample to equilibrium with the standard atmosphere from the dry side of the hysteresis curve by-first preconditioning the test sample. Clearly, if the test siimple were to be conditioned from the wet side, the results would be totally uncomparable with tests conducted on preconditioned specimens,... 

ASTM D 26I2 -91- Fiber cohesion in. sliver and top in static tests. 

ASTM D 4120 93 Test method for fiber cohesion in roving, sliver, and lop in dynamic tests... 

Yarn Assembly of staple fibers or filaments produced by spinning establishes fiber cohesion by... 

There are several primary properties necessary for a polymeric material to make an adequate fiber (1) fiber length to width ratio, (2) fiber uniformity, (3) fiber strength and flexibility, (4) fiber extensibility and elasticity, and (5) fiber cohesiveness. 

Fiber Cohesiveness Fibers must be capable of adhering to one another when spun into a yam. The cohesiveness of the fiber may be due to the shape and contour of the individual fibers or the nature of the surface of the fibers. In addition, long-filament fibers by virtue of their length can be twisted together to give stabil ity without true cohesion between fibers. Often the term "spinning qual ity" is used to state the overall attractiveness of fibers for one another. 

Before the filament or staple is used in yam spinning, spin finishes are added to give lubricity and antistatic characteristics to the fibers and to provide a greater degree of fiber cohesiveness. Such finishes are usually mixtures including such materials as fatty acid esters, mineral oils, synthetic esters, silicones, cationic amines, phosphate esters, emulsifiers, and/or nonionic surfactants. Spin finishes are formulated to be oxidation resistant, to be easily removed by scouring, to give a controlled viscosity, to be stable to corrosion, to resist odor and color formation, and to be non-volatile and readily emulsifiable. 

Features Improves fiber cohesion reduces fiber friction... 

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