Green and controlled synthesis of short diol oligomers from polyhydroxyalkanoate to develop fully biobased thermoplastics

Polyhydroxyalkanoates (PHAs) are a biodegradable and biobased family of bacterial polyesters with different architectures. Among them, the poly-3-hydroxybutyrate (PHB) is one most conventional easily obtained by biotechnologies from bioresources. However, this thermoplastic polyester known since more than 50 years presents until now only very limited applications due to certain number drawbacks such as poor mechanical properties, high degree crystallinity, low thermal stability. One major way valorize could be develop controlled building blocks for synthesis new generation polymers. In way, short linear PHB diols oligomers (oligoPHB-diol) molar masses have been successfully synthetic pathway using reactive solvents in green way. Different transesterification reaction parameters were investigated control mass decrease, catalyst solvent contents, temperature type. Obtained then analyzed detail further incorporated into fully thermoplastics. work, polyurethanes (TPU) elaborated an example second-generation To obtain TPUs content, dimer fatty acid-based diisocyanate, dimeryl another diol, isosorbide, used. Two series prepared (i) varying isosorbide/oligoPHB-diol ratio, (ii) oligoPHB-diol mass. Materials evaluated their structural, well crystalline behavior. A large range properties these innovative thermoplastics which open sustainable approach.