Polybutene


Polybutene is an organic polymer made from a mixture of 1-butene, 2-butene, and isobutylene. Ethylene steam cracker C4s are also used as supplemental feed for polybutene. It is similar to polyisobutylene lower reactivity due to steric hindrance at the terminal carbon in, e.g., manufacture of polyisobutenyl succinic anhydride the molecular weight—viscosity relationships of the two materials may also be somewhat different.

Applications

Industrial product applications include, sealants, adhesives, extenders for putties used for sealing roofs and windows, coatings, polymer modification, tackified polyethylene films, personal care, polybutene emulsions. Hydrogenated polybutenes are used in a wide variety of cosmetic preparations, such as lipstick and lip gloss. It is used in adhesives owing to its. Polybutene finds a niche use in bird and squirrel repellents and is ubiquitous as the active agent in mouse and insect "sticky traps."
An important physical property is that higher molecular weight grades thermally degrade to lower-molecular weight polybutenes; those evaporate as well as degrade to butene monomers which can also evaporate. This depolymerization mechanism which allows clean and complete volatization is in contrast to mineral oils which leave gum and sludge or thermoplastics which melt and spread. The property is very valuable for a variety of applications. For smoke inhibition in two stroke engine fuels, the lubricant can degrade at temperatures below the combustion temperature. For electrical lubricants and carriers which might be subject to overheating or fires, polybutene does not result in increased insulation or conductive carbon deposits.