Meaning
Equilibrium partition coefficients express the linear relationship between partial pressure and dissolved gas concentration within a solid polymer phase. A henrys law constant measures the solubility limit of volatile migrants or atmospheric gases inside amorphous packaging resins under low pressure conditions. The relationship governs gas absorption during storage and initial degassing steps in solid-state recycling operations.
High gas concentrations break this proportionality, requiring dual-mode sorption models that account for matrix swelling.
Linearity Boundary
Dissolved gas concentration scales linearly with partial pressure at low vapor activities. Matrix plasticization invalidates linear constants when penetrants swell the polymer structure.
Sorption Equilibrium
Penetrant sorption into amorphous polymer domains depends on available free volume and specific polymer-gas interaction energies. Determining the henrys law constant allows engineers to calculate maximum gas uptake during high-pressure beverage carbonation or modified atmosphere packaging exposure. Polymer density variations alter constant values, as dense crystalline zones exclude gas molecules and concentrate sorption within flexible amorphous regions.
Regrind contamination creates non-uniform sorption zones, causing local concentration spikes during storage.
Permeation Effect
Temperature increases suppress gas solubility while accelerating molecular diffusion rates. Lowering the henrys law constant reduces total gas storage capacity within container walls, affecting carbonated beverage shelf life.
