3M K25

Glass Bubbles K25 glass bubbles have a density of 0.25 g/cc and an isostatic crush strength of 750 psi. These general purpose spheres have a good strength-to-density ratio and are designed for use in a variety of intermediate depth (e.g up to 5,000 feet of sea water) buoyancy applications, such as drill riser buoyancy modules.

What are Glass Bubbles?

The general purpose K Series glass bubbles are the most versatile and economical Glass Bubbles. Our Glass Bubbles K25 are engineered hollow glass spheres made from water-resistant and chemically-stable soda-lime borosilicate glass. Like all glass bubbles, our K25 glass bubbles are water and oil resistant, providing better utility in underwater applications and creating more stable emulsion explosives. Additionally, they are non-combustible and non-porous, so they do not absorb resin; and their low alkalinity makes this product compatible with most resins while providing a stable viscosity and a long shelf life.

Glass bubbles are a superior alternative to many conventional fillers and additives such as silicas, calcium carbonate, talc, clay and other materials used in demanding applications. Our low-density spheres are used in a wide range of industries to reduce part weight, may lower costs and enhance product properties – making them more reliable and affordable than many alternatives such as cenospheres and perlite.

Strength-to-Weight Ratio

The benefits don’t end there; although these hollow spheres have thin walls, they have an isostatic crush strength of 750 psi, making them suitable for a number of buoyancy applications, including additives in buoys and shallow water buoyancy applications (e.g. up to 5,000 feet of sea water). K25 bubbles have a fractional survival rate of 80% or more, at 750 psi for consistent performance in highly filled resin systems.