Also called Colloidal or Fumed Silicas and/or Cabosil.
Aerosil 200 is a hydrophilic fumed silica used to alter properties of paints, coatings, unsaturated polyester resins, laminating resins, gel coats, HTV- and RTV-2K- silicone rubber, adhesives, sealants, printing inks, cable compounds, cable gels, and plant protection.
Used for altering the properties of resin to change thixotropy, add viscosity, or increase bond strength. Use to prevent draining from glue joints or on vertical surfaces. Use in combination with other fillers to improve working properties and minimize draining with polyester and epoxy resins.
When mixed with resin they form a very hard surface that is hard to sand but very heavy, durable and tough.
Microballons and Qcell have the same effect and when mixed with resin forms a filler that is lightweight, easy to sand and shape but not nearly as hard and durable as Cabosil. Can be mixed with Cabosil to create a hybrid putty.
Best Use: When using any of the putty mixtures above it is best to catalyze the resin and then add the filler to ensure the best mixing.