The synthesis of novel polyol was carried out by the reaction of epoxidized soy-bean oil (ESBO) throught ring opening reaction with vinyl phosphonic acid (VPA) bearing two functional groups, vinyl and phosphonic acid. The synthesized polyol (PolP) and 4,4´-methylenebis(phenyl isocyanate) (MDI) were reacted to prepare biobased and inherently flame retardant polyurethane foam (PPPU). FTIR, 1 H, 13 C and 31 P NMR spectroscopy confirmed that the epoxy ring of ESBO was opened by phosphonic acid group of VPA, and vinyl group was not involved in the ring opening. The prepared polyurethane was characterized using fourier transformed infrared spectroscopy ( FTIR) and thermal properties were measured using differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). XRD was used for crystallografic structure and SEM image of polyurethane showed smooth surface. When compared to phosphorous-free polyurethanes derived from soybean oil based polyols, PPUP exibited better flame retardant property with a limiting oxygen value index of 26.4.

Silylation of epoxidized soybean oil (ESBO) was carried out by epoxy ring opening reaction of methoxy and ethoxy silane compounds. 1 H NMR and FTIR spectra confirmed that two novel bio-based polyols, PSiTh and PSiAm, were obtained through the ring opening of epoxy by the mercapto and amino moieties of MPTMS and APTES, respectively. Polyurethanes of these polyols were prepared using 4,4´-methylene-bis(phenyl isocyanate) (MDI) to incorporate silanol groups into polymer network and were labeled as PUSiTh and PUSiAm, respectively. To see the impact of silanol and phosphorous groups on flame retardant properties, the chain extended polyurethanes, PUSiThCE and PUSiAmCE were also prepared with bisphenol-A bis (hydroxy phenyl phosphonate) (BABHPP). Polyurethanes bearing thio-ether bonds besides alkoxy silane groups were characterized using FTIR spectroscopy. Prepared foams exhibited significant thermal stability and flame retardant properties with a limiting oxygen index (LOI) of 22-24%. Chain extended polyurethanes had 11-13 % higher LOI value than the corresponding non-chain extended polyurethanes.