Maximum Temperature of UHMWPE for Analytical Testing

摘要

The molecular weight of a polymer is critical to its performance properties. Ultra High Molecular Weight Polyethylene (UHMWPE) has been used more for the high tenacity fibers that can be gel extruded. These fibers are used in many bullet resistant applications. The analysis of UHMWPE is made difficult because the melting point is so high, about 135 C. One must determine the maximum temperature for complete melting UHMWPE crystals, but not so high that the polymer begins to undergo random chain scission. Random chain scission can be determined by measuring the average molecular weight. This paper will review all the methods for measuring molecular weight with their advantages and disadvantages. Most of these methods require the polymer to be soluble in a solvent. UHMWPE is difficult to dissolve and its melting point is close to the temperature where random chain scission begins to degrade the polymer and lower its molecular weight. Results will be shown using several thermal analysis techniques.