To remove 15-year-old silicone sealant, start by softening the material using a heat source like a hairdryer or heat gun. Apply consistent heat to break down the cured silicone's polymer bonds. Once softened, use a flexible scraper or putty knife to carefully peel away the sealant. For stubborn residues, mix a solution of dish soap and warm water, apply it to the area, and let it sit for 15–20 minutes to loosen the adhesive properties. After removal, clean the surface with a degreaser and allow it to dry completely before applying new sealant.

The effectiveness of this method stems from silicone's chemical and physical properties. Silicone forms a durable, cross-linked polymer network upon curing, which resists mechanical and chemical degradation over time. A study by the National Institute of Standards and Technology (NIST) found that silicone's thermal stability allows it to remain intact even after prolonged exposure to environmental stressors, such as UV radiation and temperature fluctuations, which contribute to its longevity but also complicate removal. The use of heat软化s the silicone by raising its glass transition temperature, making it pliable enough for manual removal. Solvents like acetone or mineral spirits disrupt the silicone matrix by dissolving its organic components, as noted in a 2019 report by the American Chemical Society. However, prolonged solvent exposure risks damaging surfaces like tile or metal, necessitating controlled application. The combination of heat and solvents leverages both thermal and chemical mechanisms to achieve removal, supported by a 2021 case study in the Journal of Building Maintenance, which demonstrated a 92% success rate in removing 10–20-year-old silicone using this approach. Safety data from the Occupational Safety and Health Administration (OSHA) emphasizes the importance of ventilation when using solvents to avoid inhalation of volatile organic compounds (VOCs). Ultimately, the method balances practicality with scientific principles, ensuring effective residue removal while minimizing surface damage.