The Effect of Temperature on the Optical and Analytical Properties of PET Polymer Used in Drinking Water Bottles

Abstract

Polyethylene Terephthalate (PET) polymer has been utilized in many applications including, optoelectronics, radiology and food packaging due to its resistance to weak acid, organic solvents, and oils, in addition to low density and low cost. However, physical, mechanical and optical properties of PET are highly dependent on some ambient conditions like temperature since its thermal deformation temperature is 76º C. In this work, the effect of increasing the ambient temperature on the PET material used in the fabrication of plastic water bottles was studied optically and analytically. The optical attenuation coefficient was considered at different room temperature ranging from 25 °C to 45 °C emulating hot-sun-days ambient conditions in the laboratory. The elemental composition of the selected polymers was achieved using laser induced plasma spectroscopy (LIPS) technique showing Al emission line at 257.5 nm and CN emission line at 386.1nm in the sample-generated plasma. The optical attenuation coefficient has showed a dramatic increase with the temperature which may lead to leaching of some toxic elements existed in PET polymer into the bottle’s water content during hot weather and cause health problems.