The UV-induced cross-linked network structures of methacryl-oligosiloxane nanoclusters (MONCs) were analyzed with a hydrofluoric acid dissolution derived gel permeation chromatography technique (HF-GPC) to study their network structure-property relationships. With this method the oligosiloxane cores were dissolved in HF and the remaining organic tethers underwent GPC analysis to observe the tether species and characterize the original cross-linked network structures. It was found that the MONC nanocomposites have a highly cross-linked structure, resulting in oligosiloxane cores which are completely isolated by short methacryl chain segments (two-or three-armed methacryl tethers). This structural analysis was found to be consistent with the macroscale properties of MONC nanocomposites when characterized with thermal (TGA) and thermo-mechanical (DMA and TMA) analyses.