Impact of sintering temperature and compression load on the crystallinity and structural ordering of polytetrafluoroethylene

and C-C bands, signifying enhanced chain alignment. In contrast, elevating the load from 1.2 kN to 2.4 kN at 320 °C trimmed bulk porosity from 33% to 25% without a statistically significant crystallinity change (63.0% → 64.8%). SEM cross-sections established that additional load mainly closes residual inter-particle voids rather than promoting crystal growth. Taken together, the data demonstrates that temperature is the primary driver of phase-IV hexagonal ordering, whereas load chiefly controls densification and has only a minor effect on ordering. This work, therefore, establishes a practical, low-pressure processing window 330 to 340 °C under ∼1.8 kN, which yields highly-ordered (≈72% crystalline), low-porosity (≈25%) PTFE films, providing a cost-effective route for manufacturing PTFE films and components.