4339results about How to "High modulus" patented technology

Methods of manufacturing polymeric intraluminal prostheses include annealing the polymeric material to selectively modify the crystallinity thereof. Annealing may be utilized to selectively modify various properties of the polymeric material of an intraluminal prosthesis, including: selectively increasing the modulus of the polymeric material; selectively increasing the hoop strength of the intraluminal prosthesis; selectively modifying the elution rate (increase or decrease) of a pharmacological agent subsequently disposed on or within the annealed polymeric material; selectively increasing / decreasing stress in the intraluminal prosthesis; and selectively modifying the polymeric material such that it erodes at a different rate.

Unique thermoplastic monofilament fibers and yarns that exhibit heretofore unattained physical properties are provided. Such fibers are basically manufactured through the extrusion of thermoplastic resins that include a certain class of nucleating agent therein, and are able to be drawn at high ratios with such nucleating agents present that the tenacity and modulus strength are much higher than any other previously produced thermoplastic fibers, particularly those that also simultaneously exhibit extremely low shrinkage rates. Thus, such fibers require the presence of certain compounds that quickly and effectively provide rigidity to the target thermoplastic (for example, polypropylene), particularly after heat-setting. Generally, these compounds include any structure that nucleates polymer crystals within the target thermoplastic after exposure to sufficient heat to melt the initial pelletized polymer and allowing such an oriented polymer to cool. The compounds must nucleate polymer crystals at a higher temperature than the target thermoplastic without the nucleating agent during cooling. In such a manner, the "rigidifying" nucleator compounds provide nucleation sites for thermoplastic crystal growth. The preferred "rigidifying" compounds include dibenzylidene sorbitol based compounds, as well as less preferred compounds, such as [2.2.1]heptane-bicyclodicarboxylic acid, otherwise known as HPN-68, sodium benzoate, certain sodium and lithium phosphate salts [such as sodium 2,2'-methylene-bis-(4,6-di-tert-butylphenyl)phosphate, otherwise known as NA-11]. Specific methods of manufacture of such inventive thermoplastic fibers, as well as fabric articles made therefrom, are also encompassed within this invention.