Effects of Chain Extender to the Structure of Castor Oil-Based Polyurethane Foam

Abstract

Polyurethane foam is cellular polymer that synthesized by chemical reaction between polyol and isocyanate. In this work we studied the effects of chain extender to the polyurethane foam structure that produced from polyol mixture consist of polypropylene glycol and castor oil (CO). This polyol would reacted with toluene diisocyanate (TDI) to produce urethane linkage meanwhile water and methylene chloride was added as chemical and pyshical blowing agent. A portion of chain extender ethylene glycol (EG) was added into the process as variabel proposed. One shoot process was chosen, thus ingredients was entered into stainless steel reactor consecutively followed by continuous mixing with three blade impeller. After foaming happened, liquid was pouring into wood-mold and curing at least for 48 hours. Characterization would determined such as bulk density, determination of diameter and cell density by Scanning Electron Microscopy (SEM). Functional group was analyzed by spectrum of Fourier Transform Infrared (FTIR). Result from FTIR analysis shows that adding chain extender ethylene glycol in making polyurethane based CO could improve foam structure by adding hard segment. In EG variation, minimum diameter was attained at 0,4 pphp. Furthermore cell density increased while upon 0,4 pphp it decreased and bulk density increased during adding of EG.