Reinstating Structural Stability of Castor Oil based Flexible Polyurethane Foam using Glycerol

Abstract

Use of castor oil as a renewable polyol in the polyurethane foams has been creating an attractive research interest for many researchers since last 5 decades. In this article, we examine the structural stability of flexible polyurethane foam produced using castor oil-glycerol blend by complete replacement of synthetic polyol. Addition of castor oil in the foaming blend as a complete substitute of synthetic polyol results in instability of foam. However, addition of glycerol as a crosslinking agent in the blend helps in overcoming this instability. Cellular morphology, segmented phase morphology and bulk properties of foams were investigated using scanning electron microscope, Fourier transform infrared spectroscopy respectively. Castor oil-glycerol blend significantly improves the foaming process at low concentrations (till 15 wt % glycerol) whereas, at higher concentrations volumetric expanding liquid undergoes faster cross-linking leading to retarded foam growth (above 20 wt % glycerol). Strut thickness shows a sharp decline at 25 wt % glycerol. Polymer phase morphology shows absence of H-bonded urea resulting in discrete hard segmented morphology whereas urea domains undergo agglomeration without glycerol. Foams were also characterized for thermal and bulk mechanical properties.

Review on disposal, recycling and management of waste polyurethane foams: A way ahead

“…Also, it has been demonstrated (Evtimova et al, 2003;Ghaderian et al, 2015) that PET bottles can be recycled to produce polyester polyols which can be used to produce rigid PUFs.The ever-growing problem of environmental pollution has caused the need for a low energy-consuming and high technology processing system for the synthesis of PUs from bio-based sources (to produce polyols) have caused a paradigm shift to renewable and biodegradable resources from traditional ones derived from oil and natural gas. Vegetable oil sources, for example soybean (Mizera and Ryszkowska, 2016;Spontón et al, 2013), castor (Bernardini et al, 2015;Huang and Wang, 2017;Ng et al, 2017;Oprea et al, 2016;Shaik et al, 2020Shaik et al, , 2021Sharma et al, 2014Sharma et al, , 2016, palm (Ng et al, 2017), sunflower (Das et al, 2013) and jatropha are now being explored assayed and studied as a potential to produce polyols and subsequently PU. Also, PU can be tested by blending with suitable compounds that will enhance both its mechanical and thermal properties; and make its disposal easier, like polylactic acid (Jaso et al, 2015), phosphorylcholine (Fang et al, 2014).…”

Foam stability and thermo-mechanical properties of micro/nano filler loaded castor oil based flexible polyurethane foam

“…In recent times, research is focused towards investigating the incorporation of environment friendly (i.e., vegetable derived) constituents for the synthesis of polyurethane foam [3,4]. Various vegetable oils and plant derived polyols such as soy oil [5][6][7][8][9][10], rapeseed oil [11,12], palm oil [13][14][15][16], castor oil [17][18][19][20][21][22][23][24][25][26][27], olive oil [28], and lignocellulose [29,30] are used in the synthesis of flexible polyurethane foams as an alternate polyol which is blended with synthetic polyol. Most of the vegetable oils and plant derived polyol requires modification by chemical reaction for introducing hydroxyl group in their parent chain [31].…”

High Yield Synthesis of Green Pyrolytic Oil via Thermal Cracking of Ricinoleic Acid Methyl Ester

“…[1,2] Biomass has the potential to be a renewable source of energy, high-value chemicals and fuels, which is progressively increasing. [3][4][5] In addition, vegetable oils, edible and non-edible oils, and their derivatives are clean forms of renewable energy, readily available natural resources alternative to fossil fuels. [6][7][8] Oils mentioned above hold significant importance, particularly in sustainable chemical production and in promoting the green chemistry principle.…”

“…Lignocellulosic biomass consisting of cellulose, hemicellulose and lignin is a rich resource of bio‐oils, biofuels, and biochemicals [1,2] . Biomass has the potential to be a renewable source of energy, high‐value chemicals and fuels, which is progressively increasing [3–5] . In addition, vegetable oils, edible and non‐edible oils, and their derivatives are clean forms of renewable energy, readily available natural resources alternative to fossil fuels [6–8] .…”