Silicone-Impregnated Materials
Silicone-Impregnated Fabric
NightHawkInLight. 2022. Recycled Bedsheets Make The Best Waterproof Tarps. Video. Retrieved from youtube.com/watch?v=z_R0gEDZhAI
In this video, a method of creating strong, water-proof tarpaulins using fabric and a silicone–naphtha solution is presented.
Specifically, a volumetric ratio of 1 part dry 'compressed' fabric to 0.75 parts naphtha to 0.15 parts 100% silicone sealant was used. The silicone-naphtha solution is prepared in advance, with the mixture being lightly agitated in a tough plastic bag until it achieves the consistency of a light maple syrup; the fabric to be treated is then placed in the bag too, let to sit until it absorbs as much of the solution as it can, and then kneaded to try and achieve an even distribution. (Any spots that weren't suitably impregnated can be placed, face-to-face, with a well-treated area and wrung together afterwards.) Finally, the impregnated fabric is hung to dry / cure for approx. 24 hours.
As an aside, it is also mentioned that, when waterproofing backpacks, etc., using this technique, a 1:1 mix of silicone and naphtha should be used and applied to the item using a brush instead.