Pore Structuring
High-pressure physical characterization techniques measure the volume and throat size distribution of accessible voids within porous materials. By forcing non-wetting liquid mercury into pore networks under controlled pressure increments, mercury intrusion porosimetry quantifies pore diameters ranging from macro-scale inter-fibre gaps down to micro-scale intra-fibre voids in technical nonwovens and filter media. This technique maps overall pore volume and pore throat diameters across dense woven and nonwoven matrices, but cannot measure closed, non-interconnected internal pores.
Intrusion Mechanism
Non-wetting liquids require external hydraulic pressure to enter solid pore apertures due to high contact angles. The Washburn equation relates applied pressure inversely to pore throat radius, meaning low pressures fill large channels while extreme pressures force mercury into sub-micron voids. Continuous recording of intruded mercury volume at corresponding pressure stages generates cumulative pore volume distributions and differential pore size frequency curves for textile substrates.
Structural Insight
Pore size distribution curves distinguish effective flow channels from dead-end pore spaces in industrial filter fabrics. Accurate pore architecture data governs liquid filtration efficiency and pressure drop predictions.
Operational Limitation
Sample distortion can occur under extreme hydraulic pressures applied during testing of delicate nonwoven webs. Laboratory reports must state whether structural compliance corrections were applied to raw intrusion data.
