PBT is thermoplastic used in electronic, electrical, medical, automotive, and sporting goods applicatons. It is mechanically strong, resistant to solvents, and heat resistance up to 150˚C. These properties give this polymer many different uses.
Butanediol is most commonly synthesized from formaldehyde, which is produced from methane. Methane is obtained from either natural gas or syngas. First, the methane is reacted with steam at moderate pressures and high temperatures to form methanol. Formaldehyde is produced from a catalytic oxidation with oxygen and methanol. The formaldehyde is reacted with acetylene which is produced by the cracking of hydrocarbons or by partially combusting methane. The formaldehyde and acetylene reaction produce butanediol.
Terephthalic acid is currently produced from the oxidation of p-xylene with oxygen. P-xylene is produced from crude oil using a process called alkylation.
Current PBT producers are DuPont, BASF, and GE plastics.
 "PBT" Omnexus, 2010 <http://www.omnexus.com/tc/pbt/index.aspx>
 "Crastin ® Polyester Resin" DuPont, 2010 <http://www2.dupont.com/Automotive/en_US/products_services/engineeringPlastics/crastinPBT.html>
 "A Guide to PBT" Polymer Technology and Science, LLC <http://www.ptsllc.com/pbt_intro.htm>