Termotropik sivi kiristalin polimerlerin yüksek denyeli filamanlarinin yapilmasi

Mevcut bulusta, bir termaotropik sivi kristalin polimerin yüksek denyeli bükümlenmis ve isiya islem görmüs filamanlarinin olusturulmasi için yeni bir islem açiklanmakta ve talep edilmektedir. Tercih edilen uygulamalar arasinda, birkaç tamamen aromatik polyesterin ve polyesteramidin bükümlenmis ve isyla islem görmüs monofilamanlarinin olusturulmasi için bir islem vardir. Islem, a) bir termotropik sivi kiristalin polimerin, erime geçis sicakliginin üstüne isitilmasi; b) söz konusu erimis polimerin, en boy orani yaklasik 1'den fazla ve yaklasik 15'ten az olan bir presleme kilcalina sahip bir presleme bölmesinde bir filaman yapmak amaciyla geçirilmesini ve c) filamanin en az yaklasik 4 asagi çekme oraninda sarilmasini içerir. The present invention discloses and claims a novel process for the formation of high denier as-spun and heat-treated filaments of a thermotropic liquid crystalline polymer. Preferred embodiments include process for the formation of as-spun and heat treated monofilaments of a few wholly aromatic polyesters and polyesteramides. The process involves (a) heating of a thermotropic liquid crystalline polymer to above its melting transition temperature; (b) passing said molten polymer through an extrusion chamber equipped with an extrusion capillary of an aspect ratio of greater than about 1 and less than about 15 to form a filament; and (c) winding the filament at a draw-down ratio of at least about 4. The filaments so formed are of at least 50 denier per filament (dpf) and feature essentially uniform molecular orientation across the cross-section. In a final optional step, the filaments are heat treated in stages to form filaments exhibiting excellent tensile properties. Both as-spun and heat-treated filaments feature remarkably good tensile properties retaining at least 80 to 90 percent of the properties expected of conventional low denier (5 to 10 dpf) filaments.