Silicone adhesive is conspicuous by its bonding properties, rubbery behavior, and high surface tensile strength, but it is capable of being damaged by exposure to harsh environments. Moisture and temperature were considered as imperative environmental factors in natural aging. Thus, accelerated hydrolytic aging was conducted in the laboratory to investigate the mechanism of degradation of Polydimethylsiloxane (PDMS)-based adhesive. Desalinated water and salinated water as prevailing aqueous environments were chosen for the experiments. Deterioration was evaluated by weight changes, mechanical behaviors, visual inspections, FT-IR (Fourier-Transform Infrared) Spectroscopy, DMA (Dynamic Mechanical Analysis), and SEM (Scanning Electron Microscopy) tests. Increasing water uptake is proportional to decreasing tensile strength and escalation of elongation at break after desalinated water immersion. This phenomenon is indicated as a continued expansion of plasticization, which mainly reflects the reduction of Tg. In the case of salinated water, water uptakes of specimens were impeded by sea salt. This research is designated to cope with the application of silicone sealant in harsh environments.
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