Greener rigid polyurethane nanocomposite foams: investigation of physico-mechanical properties formulated with eco-friendly blowing agents

In the current investigation, two different grades of bio-based polyols have been used to formulate rigid polyurethane foams (RPUFs). Environment-friendly blowing agents having low ozone-depleting potential like cyclopentane (CP) and methyl formate (MF) were employed to produce greener RPUFs. The prepared foams were evaluated for their chemical structure, cellular structure, free rising density, compressive strength and thermal properties. The formation of characteristic urethane linkage in the foams has been confirmed by Fourier transform infrared (FT-IR) studies. Scanning electron microscopy (SEM) results showed uniform cellular morphology of the RPUF blown with CP. The improved compressive strength of RPUF could be achieved with CP as a blowing agent along with low thermal conductivity. To further enhance the dimensional stability, functionalized multiwall carbon nanotubes (f-MWCNT) have also been introduced into CP-based RPUF and physico-mechanical properties have been investigated.