HYDROPHOBICITY WITH RENEWABLE TECHNOLOGY
Cardolite offers a line of renewable, cashew nutshell liquid (CNSL) based polyols that have unique qualities compared to widely known polyester and polyether polyols, and other natural oil based polyols. CNSL polyols and diols are very hydrophobic because of the long aliphatic chain of cardanol, and fewer ether oxygen atoms compared to typical polyether polyols (less hydrophilic). This hydrophobicity provides excellent water resistance and less moisture sensitivity during cure with isocyanate for increased durability of the final polyurethane system.
The experiment shown on this page is an attempt to quantify the relative water resistance in PU systems of different polyols and diols. When NCO reacts with water, it releases CO2. Other than in moisture cured systems, the reaction of NCO with water is undesirable, and the goal is to react the NCO only with the polyol. In this test, a mixture of polyol/NCO (Index 100) is poured over the same amount of water and the amount of CO2 released is measured. The results indicate CNSL diols and CNSL polyols are more hydrophobic than PPG diols and castor-based polyols, respectively. NX-9201 is very close to PolyBD in performance, but at lower price.