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A rapid method for the measurement of the critical surface tension γ c values of individual wool fibers is described. Using this method, a comprehensive study of the wettability of untreated wool fibers has been carried out, and subsequent changes in γ c after various chemical treatments have been monitored. It is shown that the value of γ c obtained depends on the liquid series used for the measurement; the use of aqueous alkanol solutions for such measurements is criticized. The value of γ c for Hcrcosset-57 has been measured, and the spreading coefficient S and work of adhesion WA for this polymer on wool have been re-evaluated.

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X-ray photoelectron spectroscopy (XPS) is used to investigate the chemical modification of wool fibers arising from gaseous fluorination. Oxidation of the disulphide bond occurs together with a concomitant decrease in felt shrinkage.Felting shrinkage of wool during laundering occurs primarily because the surface cuticular structure of the fiber causes a directional frictional effect [ 7,8 ] . The . . current commercial chlorine/Hercosett process, although highly successful, is now under pressure from environmental legislation, due to the formation of ad-sorbable organohalogens (AOX) during processing. This paper examines the nature of the gaseous fluorination of wool as an alternative shrinkproofing system.Fluorination has a number of important advantages over current chlorination processes: it is a dry process operating at commercially acceptable processing speeds, with organofluorides being undetected by cur. rent AOX testing and probably presenting fewer environmental problems.

In previous studies, we found that Young's moduli of quenched isotactic polypropylene/high-density polyethylene (iPP/HDPE) exceeded the upper bound, calculated from the Voigt model, with the moduli of the quenched homopolymers as those of the two components. We suggested that this might be due to crystallization, as the components crystallized at higher temperatures in the blend than on their own. We repeated the same set of measurements, this time on iPP/HDPE blends that were cooled slowly. We also examined crystallization at various rates of cooling with differential scanning calorimetry. At slow cooling rates, the HDPE and iPP components in the blends crystallize at lower temperatures than in the pure homopolymers, suggesting that the presence of one component inhibits rather than promotes the crystallization of the other. Electron microscopy of slowly cooled blends revealed very different interfacial morphologies depending on whether the HDPE or the iPP crystallizes first. Young's moduli of most of the blends lie on the upper bound; however, some blends with co-continuous morphologies fall well below the lower bound. The mechanical properties are discussed in terms of the interfacial morphology, the crystallization behavior, and the large-scale phase separation.

The application of uv curing and corona discharge technology to textiles is introduced and discussed, The influence of uv photoreactive monomer on the shrinkage and mechanical properties of corona and nonpretreated 100% wool gabardine fabric is detailed. Machine washability can be achieved at low add-on by incorporating a uv curable silicone into the formulation and a post-cure steam treatment.. Concern over environmental pollution is encouraging the development of low or zero effluent processes for wool. One area of particular concern is the production of machine washable or shrink-resistant wool.Current processes are based on applying preformed polymers from aqueous dispersions (although certain examples can be applied from solvents-silicone DC , 109 ) using an exhaust or pad method [ 13 t. At present, approximately 70% of all wool rendered machine washable is processed in the top form using the (;sIRol tws/Chlorine/Hercosett process [ 2 ] .Chlorination prepares the fabric for the application of the Hercosett polymer (encouraging exhaustion and adhesion ), but also has the additional advantage of partially shrink-proofing the wool [ 13 ] . Although chlorination is both cost effective and suited to this role, it does lead to the presence of adsorbable organohalogeñ ( Ac~x ) in the effluent. Because of the quantity of wool processed this way/the effluent does present a problem [2J.. This paper describes work to develop a dry process for producing shrink-resistant wool by applying a solventless uv -curable polymer system on corona pretreated and non-pretreated wool fabrics.

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