Polibutilene

Polibutilene, also known as polybutylene, is a thermoplastic polymer belonging to the polyolefin family. It consists of repeating butylene units, derived from butene monomers such as but-1-ene or but-2-ene. The polymer's chain architecture can be tailored by the catalyst and polymerization method to yield linear, branched, and varying tacticities (atactic, isotactic, syndiotactic). These structural differences control crystallinity, density, and mechanical behavior.

Industrial production relies on coordination catalysts, notably Ziegler–Natta or metallocene systems, in gas-phase, slurry, or solution polymerization. Process conditions determine molecular weight, branching, and stereoregularity.

Polibutilene exhibits properties typical of polyolefins: it is thermoplastic and moldable, with moderate impact resistance, good ductility, and chemical resistance to many solvents and fuels. Crystallinity and melting behavior vary with tacticity and molecular weight, yielding grades from flexible films to tougher, opaque solids. Thermal stability is adequate for many consumer and industrial applications, but UV exposure can lead to aging if stabilizers are not used.

Common applications include piping and fittings (historically polybutylene piping systems), sealants and adhesives, coatings, and flexible packaging. Some grades are formulated for automotive components and consumer electronics housings.

Recycling of polibutilene follows standard polyolefin routes, including mechanical reprocessing and energy recovery. Safety, environmental impact, and compatibility depend on additives, fillers, and end-use conditions.