Joint influence of γ-irradiation and high temperature shear grinding on the IR spectra and surface-energy properties of polyethylene

The optical and surface-energy properties of polyethylene (PE) subjected to gamma-irradiation and post-radiation, high temperature, shear grinding are presented. Comparison of the IR spectra of the initial and gamma-irradiated PE shows that oxygen-containing groups and unsaturated bonds in the polymer macromolecules are formed and accumulate during their radiolysis in air, increasing with gamma-irradiation dose. A redistribution of the products of radiation-chemical conversion on the surface of the polymer granules throughout the entire volume of the powder occurs after high-temperature shear milling to a powder as observed in the IR spectrum. Polar functional groups due to oxidation reactions are observed on the surface layer of the sample after post-radiation grinding. The initial polymer surface is weakly basic with an acidity parameter of -0.34. The value of the acidity parameter of the sample made of ground irradiated PE has an acidic surface with an acidity parameter of 0.65. gamma irradiation of the secondary processing of PE waste with high-temperature shear grinding is a promising approach to obtain a secondary PE powder with specified parameters and different degrees of functionalization.

Automated summary

The study investigates the optical and surface-energy properties of polyethylene under different treatment conditions, including gamma-irradiation, high temperature, and shear grinding. It is found that oxygen-containing groups and unsaturated bonds are formed and accumulated during the treatment process, leading to the generation of polar functional groups on the sample surface.