Infrared Optical Properties of Polar Ethylene Copolymer Films for Transparent Insulation and Greenhouse Applications

摘要

Polymer films are widely used for various solar energy applications, such as transparent insulation or greenhouses. The optical properties of the materials in the infrared range are of special importance for the heat transport. In this paper infrared optical properties of novel polar ethylene copolymer films are described and discussed. The properties were determined based on infrared transmittance and the assumption of a constant index of refraction from the visible. For the investigated polar ethylene copolymer films with thicknesses of about 100 μm hemispherical emittance values for a temperature of 20°C from 0.16 to 0.35 were obtained. The infrared emittance is mainly affected by the concentration of carbon-oxygen single bonds and thus by the comonomer content.