Molecular weight and crystallinity are two factors in PTFE that determine many of it's performance qualities. Both of these properties are highly dependant on the sintering operation of the PTFE production. If the material is cooked (sintered) too long or at too high a temperature it can degrade the polymer. Molecular weight is a measure of the polymer chain length and it affects flex life, tensile strength and elongation. As molecular weight increases so do these properties and paying attention to gel temperatures and dwell times during sintering is extra critical.