In unsaturated polyester resin (UPR) applications such as SMC, BMC, lay-up, spray-up, casting and injection molding, TBS is an excellent diluent because of its low vapor pressure, high flash point, low shrinkage on polymerization and reduced exotherm. Higher operating temperatures are possible resulting in formulations with reduced viscosity, faster polymerization and cycle times, and the elimination of mold scum. TBS/UPR resins result in products with improved heat distortion and improved corrosion resistance.
TBS monomer can be polymerized by any of the conventional ways of initiation and in the presence of inert materials such as fillers, dyes, solvents, resins, rubbers and plasticizers. Unlike polystyrene, the homopolymer of TBS is soluble in hydrocarbons due to its aliphatic nature. TBS can be copolymerized with other monomers while requiring minor recipe adjustments when replacing styrene monomer on a mole-for-mole substitution.
TBS is the ideal monomer for use with alkyd and drying oil resins when greater aliphatic compatibility is desired. Also, the higher flash point of TBS permits higher operating temperatures resulting in shorter reaction times. In addition to improved aliphatic compatibility, TBS provides higher molar volume and improved thermal stability when used in manufacturing hydrocarbon resins.
Typical precautions in handling TBS monomer include wearing protective clothing, the use of impermeable gloves and use in a well ventilated area. Do not store in direct sunlight. Maintain storage temperature below 75oF if extended storage is required. TBS monomer contains the polymerization inhibitor tertiary butylcatechol (TBC) to reduce polymer formation during storage. For other product safety and toxicological information, please consult the Material Safety Data Sheets for TBS monomer.