Thermoplastic resins containing PBT units, having reduced organic carbon emissions

A method for reducing outgassing of tetrahydrofuran (THF) in copolyether ester elastomers having polybutylene terephthalate (PBT) repeat units and polymerized in the presence of a titanium catalyst,

• the method comprising the step of:
• adding to the copolyether ester elastomer after polymerisation a titanium catalyst deactivating compound,
• wherein the titanium catalyst deactivating compound is selected from the group consisting of a compound of Formula IV, salts of Formula IV, a compound of Formula IV′, and salts of these,
• wherein R1, R2 and R3 are independently selected from H, OH, OM (wherein M is a positively charged counterion), optionally substituted C1-20 alkyl, optionally substituted C2-20 alkylene, optionally substituted C6-20aryl, optionally substituted C1-20 alkyloxy, polyoxy(C2-4)alkylene, and optionally substituted C6-20 aryloxy, and wherein the optional substituents are independently 1 to 2 in number on any of R1, R2 and R3, and are independently selected from OH, halogen, COOH, COOR4 (wherein R4 is C1-4 alkyl) and NH2;
• two or more of R1, R2 and R3 can be optionally linked together by a bridge;
• with the provisos that for Formula (IV) R1, R2 and R3 are not simultaneously OH, and R1, R2 and R3 are not simultaneously H;
• and
• for Formula (IV′), R1 and R2 are not simultaneously OH.