Flory-Huggins Based Approach to Describe Phase Separation in Reactive Ternary Mixtures of Polyether Polyol Blends and Hexamethylene Diisocyanate

摘要

Compatibility between raw materials in the field of polyurethanes is of major importance for the characteristics of the final product. Regarding elastomers incompatibility is often purposely introduced to improve for example mechanical properties by phase separation of hard and soft segments. Literature mainly focused on this hard-/soft segment segregation. Quite recent bi-soft segment urethanes, without hard segment blocks, were introduced as a promising membrane material. This study focuses on the onset of liquid/liquid phase separation in reactive isocyanate/bi-soft segment mixtures. Scope of this work is to discuss this in the context of solubility parameter based Flory Huggins theory and hydrogen-bonding at the carbonyl moieties.