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The effect of the glass transition temperature and the number of anionic groups of Dralon, Courtelle and Euroacril on the dyeing rate constants, Arrhenius activation energy and time-temperature cycle of isoreactive dyeing systems was studied. The dyeing rate constants depend more on the glass transition temperature than on the number of anionic groups, although these also have some effect. The Arrhenius law is followed in the glass transition range for the acrylic fibers; however, the experimental activation energy is not a suitable parameter for assessing the dyeing rate as it depends on the opening of the fiber. The isoreactivity equation was used to obtain time-temperature conditions leading to linear exhaustion during the dyeing process. Optimal conditions for a level dyeing of fibers may be determined through temperature control. [ABSTRACT FROM AUTHOR]

This paper has reviewed several studies, particularly those performed on the phosphate polymers, in which ionic forces were important in determining the properties or behavior of the material. Only very few properties were investigated; among these were 1) the glass transitions as a function of the molecular weight, the nature of the terminal group, and the nature of the counterion, 2) the viscoelastic properties as a function of the counterion and 3) the viscoelastic relaxation mechanism, with specific emphasis on the separation of the α and x mechanisms. In this treatment, a deliberate attempt was made to present pertinent theories, insofar as they exist, but it seems evident that here as much work remains to be done as on the experimental level, if not more. A host of other properties remain to be investigated quantitatively, although a beginning has certainly been made. These include the effect of various types of ionic interactions on organic materials (Sect. I-B) including both crystalline and amorphous polymers. Only bulk properties have been discussed here, but although the literature on polyelectrolyte solutions is voluminous, the transition region between these two areas, i.e., that of the plasticized ionic polymers, again has not received its due attention, perhaps due to the difficulties encountered in both the theoretical and experimental approaches. [ABSTRACT FROM AUTHOR]

Polyurethane chains consist of alternating flexible and rigid segments. The properties of the resultant coating depend upon the chemical nature and distribution of these segments. The chemistry of various ure thanes is described in relation to the properties and utility of the coatings derived from them. [ABSTRACT FROM PUBLISHER]

The section of "The Production and Properties of Nonwoven Fabrics" focuses on adhesive-bonded fabrics. In such fabrics, fibre webs are strengthened by fibre-to-fibre adhesion. The tensile strength of such fabrics depends upon the binder cohesion whether the adhesion between the fibre and the binder is adequate. The range of binders that are available to the manufacturer of adhesive-bonded fabrics has increased. It is stated that higher the value of the glass transition temperature (Tg), the stronger will be the resultant nonwoven fabric. The adhesive is required to possess some properties including requisite flow properties, no fire hazard, no toxic fume hazard, and possess cohesive strength.

The article presents information on technical literature related to the textile chemical industry. A 16-page brochure has been published by Foxboro on its Fox 1 process management and control systems. B.F. Goodrich Chemical has released three new publications on the properties of latex, methods of avoiding foam formation and importance of glass transition temperature in latexes. An 8-page brochure has been published by Nopco Chemical on its line of textile defoamers for wet processing. A dictionary has been published by Fairchild Books which covers the decorative home furnishings industries. Written by Emanual Hoffman, the dictionary includes sections on furniture and bedding, accessories, curtains and draperies, fabrics and fibers, and soft and resilient floor coverings.

Glass transition measurements on monodispersed polystyrenes of different molecular weight and their binary mixtures result in the following conclusions: (a) the effect of molecular weight on the glass transitions of monodispersed samples satisfies the Fox and Flory equation written as T g = T g ∞ - A / M n , with constant A = 0.84 × 10 -5 ; (b) polymers of the same number average molecular weight with a broad distribution show lower glass transitions than the monodispersed; (c) the binary mixtures follow the Gordon-Taylor equation derived for copolymers, with constant k (experimental) 0.5.

Heat capacities of two high density linear polyethylene samples were measured from 2 to 360 K. By incorporating the results from the previous work of this series, thermodynamic properties of completely crystalline linear polyethylene may be estimated. C p , H - H 0 , S and - (G - H 0 ) at 298.15 K for crystalline linear polyethylene are estimated to be 22.60 J K -1 mol -1 , 3544 J mol -1 , 23.02 J K -1 mol -1 and 3319 J mol -1 , respectively. Spontaneous adiabatic temperature drifts were observed in both samples near 240 K. These drifts may be attributed to the enthalpy relaxation phenomena occurring in the glass transformation region.