Nowadays increasing interest is observed for using of bio derived products replacing petroleum based materials. This may reduce the fuel consumption and result in producing of materials with lower envi ronmental impact. One of such substances is vegetable oil, which possesses unique chemical structure and consists of unsaturation sites, epoxies, hydroxyls, esters and other functional groups along with inherent flu idity characteristics. Such outstanding features enable them to undergo various chemical transformations producing low molecular weight polymeric materials with versatile applications. Our review discusses the synthesis of polyurethane from castor oil and provides an insight of its prominent applications of castor oil based polyurethane as hybrid materials, interpenetrating polymer networks, foams, adhesives, coatings.

In this study, we have reported the synthesis of modified polyol from tung oil. The synthesis involves three steps: first, conversion of tung oil to hydroxylated tung oil by hydroxylation; second, alcoholysis with triethanolamine; and finally, the esterification of polyester polyol when reacted with phthalic anhydride (PA) or maleic anhydride (MA). Boric acid is also introduced into the polyol by chemical modification, which enhances the thermal properties of polyurethane foam (PUF). PUF is formulated by the reaction between polyol and isocyanate. A systematic comparison of flame retardancy and mechanical and thermal properties of modified PUF has been examined. The structural properties of modified polyol were characterized by Fourier transform infrared spectroscopy, proton NMR spectroscopy, and gel permeation chromatography, while the thermal and mechanical properties of the formulated PUF were studied by scanning electron microscopy, limiting oxygen index, differential scanning calorimetry, Izod impact, and flexural and compression strength. Thus PUF prepared from modified polyol with a proper distribution of soft and hard segments possesses better mechanical and thermal properties. The PA-modified foams show better properties compared to unmodified and MA-modified foams due to the aromaticity and crosslinking behavior of PA.

Use of polyester‐type polyurethane foam (PUF) is an effective adsorbent for the removal of hazardous dye: crystal violet (CV) from an aqueous solution. In this adsorption study, the formation of hydrophobic ion pair (opposite charge attraction) between the charged species, i.e., cationic (basic) dye CV and anionic surfactant sodium dodecylsulfate (SDS) sorbed onto PUF. Chemical calculations were performed using quantum simulation to understand ion‐pair formation for CV–SDS at the semiempirical PM6 level. Adsorption studies were performed using 200 mg cylindrical PUF with an overhead stirrer in solutions containing varying compositions of the dye–surfactant mixture. The equilibrium thermodynamics and kinetics of the adsorption process were studies by measuring CV dye removal as a function of time and temperature. Results show that the formation of the dye–surfactant ion pair is necessary for effective adsorption onto PUF. Various adsorption isotherms, viz., Langmuir, Freundlich, Temkin, Dubinin–Radushkevich (DRK), Harkin‐Jura, and several kinetic models, viz., pseudo‐first order, pseudo‐second order, Elovich, and Intraparticle diffusion were used to fit the spectrophotometric result. The equilibrium adsorption data fit to the Langmuir isotherm gives the maximum adsorption of PUF as 33.39 mg g−1 from 200 mL 5.0 × 10−5 mol L−1 CV solution at 298.15 K. The kinetics study showed that the overall adsorption process follows pseudo‐second‐order kinetics. The Morris–Weber model suggests that an intraparticle diffusion process is active in controlling the adsorption rate. The Freundlich, Temkin, DRK adsorption isotherms showed that solute dye transfers from solution to the PUF adsorbent surface through physical adsorption. The Langmuir and Harkin‐Jura adsorption isotherms suggest that the adsorbent surface is homogeneous in nature. The thermodynamic data showed that the adsorption process is spontaneous and endothermic with a positive enthalpy change and a negative change in Gibb's energy.

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This study illustrates the modification of the Poly-Urethane Foam (PUF) prepared from the Tung Oil (TO) and later impregnating it with varying ratio (~ 1 to 5 w/w%) of Activated Carbon (AC) which enable this modified entity to act as an effective adsorbent for the solvent and oil removal from the water. After its modification, it was found that the PUF impregnated with 5 w/w% AC displayed an enhanced solvent and oil adsorption capacity. The reusability of the adsorbent was observed to decrease with increasing number of cycles. Furthermore, the adsorption conduct was calculated in a batch-type process and validated using equilibrium and kinetics study. Here, the surface-modified PUF sorbent was characterized employing Scanning Electron Microscopy (SEM) and Contact Angle (CA) wettability study. Our findings inferred that with increasing AC ratio in the foam, its pore size and CA increases thereby enhancing the adsorption capacity making this proposed study to be more expedient for sustainable environment safety.