Thermal behavior, textile fibers

Researchers have examined the creep and creep recovery of textile fibers extensively (13-21). For example, Hunt and Darlington (16, 17) studied the effects of temperature, humidity, and previous thermal history on the creep properties of Nylon 6,6. They were able to explain the shift in creep curves with changes in temperature and humidity. Lead-erman (19) studied the time dependence of creep at different temperatures and humidities. Shifts in creep curves due to changes in temperature and humidity were explained with simple equations and convenient shift factors. Morton and Hearle (21) also examined the dependence of fiber creep on temperature and humidity. Meredith (20) studied many mechanical properties, including creep of several generic fiber types. Phenomenological theory of linear viscoelasticity of semicrystalline polymers has been tested with creep measurements performed on textile fibers (18). From these works one can readily appreciate that creep behavior is affected by many factors on both practical and theoretical levels. 

Flame-retardant textiles are textiles or textile-based materials that inhibit or resist the spread of fire. Factors affecting flammability and thermal behavior of textile include fiber type, fabric construction, thermal behavior of textile polymer and its composition as well as the presence or absence of flame additives. On the other hand, flame-retardant additives can be classified by their chemical composition or by mode of action, i.e., gas phase action or by the formation of protective barrier [49, 50]. Moreover, flame-retardant functional finishes of cellulose-based textiles can be accomplished by [i] using inorganic phosphates, (ii) with organophosphorous compounds, [iii) with sulfur-derivatives or (iv) by grafting flame retardants monomers [49,50]. 

When A = 1, this expression reduces to Langmuir s equation for monomolecular adsorption. If 0 < A < 1, there is a finite maximum hygroscopic moisture content. While many textile fibers approach such a moisture content asymptotically at high relative humidities, some man-made fibers such as nylon and viscose appear to have well-defined maximum hygroscopic moisture contents [9]. In many cases, the coefficient k is greater than 1. Jaafar and Michalowski [8] interpret this behavior as the thermal effect of adsorption being equal to the heat of condensation only after a multimolecular layer has been formed. 

In view of the restrictions in space, it is impractical to review the immense volume of literature that describes the application of thermal analysis methods to textile fibers, yams, and fabrics. The objective of this section is therefore to describe examples of thermal processes in textile materials that have been selected to illustrate the behavior observed in specific samples. Comparison with these examples may help to identify and interpret similar processes and understand the performance of other materials. 

From the preceding description of the structure of polymers in fibers, the mechanical and thermal stresses that are applied during manufacturing, texturing or textile fabric production, the additives that are deposited onto the surface during processing or with the purpose of introducing specific behavior in the final fiber, yam or textile, it is clear... 

Mineral fillers and mineral fibers also increase temperature resistance. Phenolic resin-bound textile non-wovens exhibit excellent properties regarding changing climatic conditions, aging behavior, and thermal resistance compared to other insulation materials (PUR, PS foams, crosslinked PE). 

Bernard Milter has been Associate Director of Research at Textile Research Institute, Princeton, NJ, since 1970. He received his Ph.D. degree in Chemistry from McGill University followed by a number of industrial and academic appointments. He was a Fiber Society National Lecturer, 1973-1974 and has served on the Executive Committees of the Information Council on Fabric Flammability and the North American Thermal Analysis Society. In 1977, he received the Harold DeWltt Smith Medal of the American Society for Testing and Materials for his work in fiber and textile measurements. His major fields of interest are the thermal and combustion behavior of polymers, fabric flammability and the surface properties of fibrous materials. 

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