Sodium silicate, also known as waterglass is available as a high viscocity and density 140Tw (~54% concentration) and low viscocity and density 75Tw (~36% concentration).
Buy Sodium Silicate
140Tw (High viscocity)
75Tw (Low viscocity)
Sodium Silicate, also called waterglass, has a very wide range of applicaitons, including an adhesive or binder, especially in high temperature environemnts, it is a major component of most exhaust repair puttys. Sodium silicate (waterglas) solutions are used to preserve fresh eggs by sealing the pores in the shell, keeping bacteria out and water in. Sodium silicate can be used with calcium chloride to treat cardboard mortars using the method in this link.
Viscocity (Similar to)
SAE 10 Motor Oil
Irritating to the skin. Risk of serious damage to eyes. Keep out of reach of children. In case of contact with eyes rinse immediately with plenty of water and seek medical advice. Wear suitable gloves. Wear eye and face protection.