Nylons fibres with thermal

Lightweight holiow fibre thermally insulating fabrics for winter clothing have been produced by Unitika. A composition containing 98 parts nylon 6 and two parts sodium stearate treated-a-AljOj particles (AKP-30) was melt-spun to form fibres with degree of hollowness 30%, drawn and made into woven fabric exhibiting heat transmission 1.6 x 10 " W/cm°C. 

Examples of the use of blocked diisocyanates for rubber-fabric adhesion are as follows vulcanized polychloroprene and SBR can be adhered strongly to nylon and polyester fibre fabric by means of aqueous adhesive systems (Table 8.4). This combination is spread or roller coated on to the fabric which is then allowed to dry. Bonds to sheet rubber stock can be made immediately after the treated fabric is dried or at any time thereafter. When the sheet rubber is applied it should be held under moderate pressure to provide intimate contact with the treated fabric and to prevent lifting if any gases are emitted during cure. Press cures of 20-40 min at 140°C are sufficient to cure the adhesive and most elastomer compositions being adhered. If a latex film is applied to the treated fabric, the assembly can be cured in a hot-air oven at 120"C. A chemical bond results between fabric and the diphenylmethane-/7,/ -diisocyanate generated on the thermal cleavage of the blocked diisocyanate. 

Thermal welding is confined to fabrics that have high thermoplastic synthetic fibre content such as nylon, polyester, polypropylene, acrylic, and certain fibre blends. As a general mle, the textiles to be welded must be made of the same thermoplastic or be physically and chemically compatible with one another. Fabrics that have a thermoplastic coating (e.g., polyvinyl chloride, PU, and polypropylene) are also amenable to thermal-welding processes, since in these cases the coating acts as the adhesive. Weldability will vary with the type of material, its thickness, and its form (coating, film, fibre). 

In another patent, production of thermally insulative fabrics from fibres comprising 98 parts nylon 6 and two parts Na stearate-treated a-type AI2O3 (AKP-30) particles with average particle diameter 0.4 pm has been disclosed. The mixture was melt spun at 250 °C, drawn, heat-treated at 165 °C, and made into a woven fabric with heat conductivity 2.4 x 10 " W/cm°C. 

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