Properties and performance of Biosuccinium sustainable succinic acid in microcellular polyurethane elastomers

摘要

Biosuccinium sustainable succinic acid has been evaluated as alternative for adipic acid in the production of polyester polyols used in microcellular polyurethane (m-PU). It is a unique 100% bio-based product from Reverdia, the use of which increases the renewable content and reduces the environmental footprint of polyurethane formulations, while maintaining the performance required in many applications. During this research, various 2,000 g/mol polyester polyols, all based on ethylene glycol and diethylene glycol mixtures, were synthesised using adipic acid, succinic acid or a succinic/sebacic acid blend. In addition, a commercially available adipate reference (Daltorez P716) was obtained from Huntsman. Synthesis of these polyester polyols was completed without any problems and the resulting properties were within expected ranges. The main difference observed was that the succinate polyol showed some degree of crystallinity, causing a melt temperature (T_m) of approximately 50 °C; in comparison, the other polyols were amorphous and showed no transitions other than T_g. Compared to adipate systems a higher viscosity of the EDS polyol was observed as well for the polyol based on succinic/sebacic acid blend. Microcellular PU elastomers were prepared based using an MDI prepolymer with an NCO content of 19%. The ethylene glycol - diethylene glycol - succinate polyol required minor adjustments for higher processing temperature. Reactivity for all formulations was similar. For performance evaluations, moulded slabs were produced with densities in the range of 0.47-0.60 g/cm~3). The succinate elastomer showed a higher hardness compared to the adipate (48 Shore A vs. 37 Shore A). Physical properties like tear strength and elongation at break as well as abrasion resistance were quite similar for all elastomers. Results from this evaluation indicate that Biosuccinium based polyester polyols can be successfully formulated into microcellular polyurethane systems, without the need for extensive revision of formulations to produce materials with very similar mechanical performance to non-bio-based systems.