Bildu: Recopilar y Unificar Recursos Digitales de Aprendizaje para Motivar su Uso

A solid crystalline organic polymer is made into a filament, rod, or film by ultra-drawing it at a temperature within 70 DEG C. of but below its melting point at the operating pressure while subjecting the polymer during and immediately after drawing to a hydrostatic pressure of at least about 500 atmospheres applied by a fluid medium inert to the polymer. High-density polyethylene and isotactic propylene are preferred polymers. A draw ratio of at least 20:1, and as high as 60:1, may be used. Pressure may be up to 2500 atmospheres or more. The rate of drawing for polyethylene is above 500 percent per minute. The ultra-drawn products are transparent, essentially free of internal voids, and exhibit very high tensile moduli of elasticity, up to 65 to 70 Giga-Pascals in the case of polyethylene.