Isosorbide and Tricyclodecanedimethanol for the Synthesis of Amorphous and High Tg Partially Biobased Copolyesters

The synthesis and properties of amorphous poly(tricyclodecanedimethylene-co-isosorbide terephthalate) (PTIT) with the isosorbide (IS) content ranging from 0 to 68 mol % relative to the total diol amount were investigated. Surprisingly, it was found that isosorbide enhanced the polycondensation kinetics and acted as a temporary chain linker. Polymerization kinetics improvement maximum was observed when the isosorbide content was around 9 mol %. It was also found that higher molar masses were achieved when the isosorbide molar content was increased (number-average molar mass, M-n, around 16,000 g mol(-1)). The glass transition temperature linearly increased of 0.7 degrees C per mol% of isosorbide for each molar percent of isosorbide included in the polyester. The T-g values of the polyesters could be adjusted between 115 and 163 degrees C, depending on the isosorbide content. Their mechanical properties were investigated, and ductile properties were achieved up to 57 mol % of isosorbide. These properties are coupled with a very high heat deflection temperature (HDT).