Synthesis and characterization of rigid polyurethane foams from algae oil using biobased chain extenders

Polyurethane rigid foams were synthesized using algae oil-based polyol (AOP). Algae oil derived from chlorella microalgae having iodine value 120 g I-2/100 g of oil was utilized to prepare biobased polyols. Biobased polyols were prepared from algae oil via oxidation using the environmentally friendly reagent hydrogen peroxide and acetic acid followed by epoxy ring opening using lactic acid (LA-AOP) or ethylene glycol (EG-AOP). The EG-AOP contains primary as well as secondary hydroxyl groups and LA-AOP contains secondary hydroxyl groups with demonstrated ability to rapidly build polyurethane crosslinked network. The synthesized biobased polyols were formulated with methylene diphenyl diisocynate at constant NCO/OH ratio (1.2:1) using cyclopentane as a blowing agent to yield polyurethane foams (PUF 1 and PUF 2). Thermal properties of the PU rigid foams were evaluated using thermogravimetric and differential scanning calorimetric analysis, which are comparable with petroleum-based polyurethane (PPG) foam. Thermal stability of PUF 1 and PUF 2 demonstrates suitability of LA-AOP and EG-AOP for the rigid polyurethane foam preparation.