A hydrophilic blend material is a material that can take up an important quantity of water, which makes it useful in various applications such as tissue engineering, contact lenses, and drug delivery. In this study, the polymeric blend material polyhydroxyethyl methacrylate/polyethylene glycol (pHEMA/PEG) was prepared through a UV photo-polymerization reaction; hexanediol diacrylate (HDDA) and Darocur 1,173 were used, respectively, as a cross-linking agent and a photoinitiator. The main objective of this investigation was to evaluate the impact of the PEG content on the thermal and mechanical properties of the crosslinked pHEMA/HDDA. Many analytical techniques, including Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), and dynamic mechanical analysis (DMA), were used, to analyze the bonding vibrations, the glass transition temperature (Tg), and the elastic and loss moduli, respectively. The complex viscosity was analyzed by a rheometer. The swelling and deswelling behavior of the crosslinked pHEMA/PEG in distilled water were studied over time. It was found that the PEG increased the polymerization rate of the HEMA monomer, and a significant decrease in the glass transition temperature was observed with increasing PEG quantity in the blend material, confirming its plasticizing effect. The mechanical, swelling kinetics, and rheology results showed a threshold effect at 1 wt.% for PEG. The docking analysis showed that there was more hydrogen bonding between the pure pHEMA’s chains, but the integration of PEG decreased the number of hydrogen bonds, which gave flexibility to the blend material, hence; this theoretical conclusion well agreed with the experimental results.