Oxygen transmission rate (OTR) refers to the measure of the amount of oxygen that passes through a material over a specific period. It is commonly used to characterize the barrier properties of packaging materials, such as films, laminates, or containers, in terms of their ability to prevent oxygen from permeating into or out of the contained product.
The OTR is typically expressed in units of volume, such as cubic centimeters per square meter per day (cc/m²/day) or cubic centimeters per square meter per 24 hours (cc/m²/24h). It quantifies the permeability of a material to oxygen and is affected by factors such as the material's thickness, moisture content, temperature, and composition.
The measurement of OTR plays a vital role in several industries, especially in the food and pharmaceutical sectors. Packaging materials with low OTR are desired for oxygen-sensitive products to prevent spoilage, oxidation, or deterioration, thereby extending the shelf life and maintaining the quality of the packaged goods.
OTR testing involves placing a sample of the material in a controlled environment with a known oxygen concentration differential on either side. The rate at which oxygen diffuses through the material is then determined using various techniques, such as gas chromatography or oxygen sensors.
Accurate assessment of OTR helps manufacturers and researchers select appropriate barrier materials, optimize packaging design, and ensure product stability and preservation.
