The production of a high-functionality RBD palm kernel-based polyester polyol

In the previous article, a diol-based RBD palm kernel polyol was prepared. It has been found that the polyurethane foam produced is only giving a good compressive strength property at 45 kg/m(3) molded density. The combinatio n of sorbitol into the polyol system resulted in a better dimensional stabi lity and improved thermal conductivity as well as enhanced the compressive strength. These were obtained by increasing the functionality of the polyol (functionality of 4.5) through introduction of high molecular weight and b ranching polyhidric compound. Direct polycondensation and transesterificati on methods were used for the syntheses. The hydroxyl value, TLC, and the FT IR were determined to study the completion of the reaction. A comparative s tudy of the mechanical properties and morphological behavior was carried ou t with the diol-based polyol. From the water-blown molded foam (zero ozone depletion potential ODP) with density of about 44.2 kg/m(3) and closed-cell content of 93%, it resulted in a compressive strength of 222 kPa, dimensio nal stability of 0.09, 0.10, and 0.12% at the length, width, and thickness of the foam, respectively, conditioning at - 15 degreesC for 24 h. The ther mal conductivity improved to an initial value of 0.00198 W/mK, tested at 10 degreesC. (C) 2001 John Wiley & Sons, Inc.