Development of aCatalyst System for Enhanced Propertiesof Coconut Diethanolamide-Based Rigid Poly(urethane-urea) Foam

Coconut diethanolamide (CDEA)-based rigid polyurethane (PU) foams are gaining prominence as a viable and promising substitute for their petroleum-based counterparts. However, the inherent autocatalytic effects from the reactive amine moieties in CDEA disrupt the conventional balance of the gelling and blowing kinetics, compromising the final PU properties. This necessitates the development of a tailored catalytic system for CDEA-based PU formulations. In this study, the influence of the different catalyst systems (single and combined) on the kinetics, chemical, physicomechanical, and thermal properties of CDEA-based poly(urethane-urea) rigid foam was systematically investigated. The variations of the catalyst system demonstrate a notable effect on the chemical and physical structure of the CDEA-based PU material. This correlates with the changes in foam’s physicomechanical properties, thus establishing a discernible catalyst-structure-properties relationship. The most favorable properties based on established standards for rigid insulation foams were attained using a catalyst system (DMCHA + DABCO-33LV), at a 0.35% w/w loading and 1:1 mass ratio, improving the compressive strength by 26.4%, compared to the single-catalyst system. This material has stable recoverability at 5% compression strain, a water contact angle of 133.3°, and a coefficient of thermal conductivity of 38.2 mW/m·K. The interplay of dual amine-based catalysis created a delicate balance of reaction rates in polymerization, producing an excellent foam structure, thus improving the foam’s physicomechanical properties. This catalytic system establishes a baseline for advancing the evolving CDEA-based polyurethane (PU) system, paving the way for a more environmentally friendly and sustainable polymer industry.