Succinic Acid: A Bio-based Building Block in Performance Driven Polyurethane Dispersions for Coatings

摘要

This paper provides an overview of the performance of bio-based succinate polyester polyols (PEPs) in polyurethane dispersions and coatings. The synthesis, characterization and performance of the bio-based succinic acid PEPs (SA-PEP) is compared to analogous adipic acid based PEPs (AA-PEP) made with common glycols such as hexanediol (HDO), butane diol (BDO), propane diol (PDO) and neopentyl glycol (NPG). In many instances the properties of the coatings follow well-established trends when polyester succinates are compared to analogous adipates in PU coatings. That is, the succinates tend to provide increased modulus and strength of the polyols without significantly changing ultimate elongation. Likewise, it was observed that the SA-PEP based PU films generally exhibit improved solvent and abrasion resistance compared to adipates. However, the systems studied here show that the branched glycols and the odd-numbered carbon glycols reduce the modulus properties of the PU compare to the more linear systems made with even-numbered glycols. Thus, these data demonstrate that with the judicial choice of the glycols it is conceivable to make PU films and coatings with bio-based succinate polyester polyols with improved sustainability with a wide range of mechanical properties ranging from rigid, tough materials to more flexible urethanes suitable for fabric and textile coatings.