In this paper we report the employment of Ti(acac)(2)(O-iPr)(2) (titanium bisacetylacetonate diisopropylate) as a novel catalyst for the synthesis of poly(butylene terephthalate) (PBT). Large scale synthesis of several polymers with the new catalytic system and with the standard catalyst Ti(O-nBu)(4) (titanium tetra-n-butylate) have been performed in a 20 L pilot plant. In the optimized reaction conditions, Ti(acac)(2)(O-iPr)(2) has shown significantly higher activity than standard catalyst, Ti(O-nBu)4. Furthermore, a stabilized PBT has been synthesized in the presence of Ti(O-nBu)(4) as catalyst with the addition of the stabilizer U626. Then, the stability of the synthesized polymers toward thermo-oxidation has been tested in a forced circulating air oven. The polymers obtained in the presence of Ti(acac)(2)(O-iPr)(2) system showed higher stability towards thermo-oxiclation than stabilized and not stabilized PBT, synthesized in the presence of Ti(O-nBu)(4). (c) 2007 Wiley Periodicals, Inc.