Hydrogels in industrial applications have received increased attention due to potential in drug eluting contact lenses and in the pharmaceutical field because of the anticipated biocompatibility of this class of materials. As one of most common commercial hydrogels, Polyethylene glycol (PEG)-based polyacrylate gels are widely used in tissue engineering and coating applications. In many cases photopolymerization is the preferred route to preparing these crosslinked networks. Hence, a thorough understanding of these photo-cured PEG-based polyacrylate network is of great interest in the further understanding of industrial applications of these materials. In this work, we probed the detailed polymer dynamics inside these photo-cured networks by using a series of analytical tools, like Nuclear Magnetic Resonances (NMR) techniques, while these bulky characters (mechanic properties, thermal properties, etc.) were also measured correspondingly. By correlating these data, several effects caused by microscopic attributes (e.g. topological properties of the network, hydrogen bonding induced clustering, etc.) of these hydrogels on their macroscopic properties (elasticity, O2 permeability, etc.) will be discussed in this thesis. The goal of this thesis, is to better understand the connection between structural/dynamic properties of hydrogel materials and their mechanic/thermal behavior, which could be used to further design the new generation of hydrogel materials.