Preparation and Characterization of Sustainable Polyurethane Foams from Soybean Oils

Abstract

Polyol derived from soybean oil was made from crude soybean oil by epoxidization and hydroxylation. Soy‐based polyurethane (PU) foams were prepared by the in‐situ reaction of methylene diphenyl diisocyanate (MDI) polyurea prepolymer and soy‐based polyol. A free‐rise method was developed to prepare the sustainable PU foams for use in automotive and bedding cushions. In this study, three petroleum‐based PU foams were compared with two soy‐based PU foams in terms of their foam characterizations and properties. Soy‐based PU foams were made with soy‐based polyols with different hydroxyl values. Soy‐based PU foams had higher Tg (glass transition temperature) and worse cryogenic properties than petroleum‐based PU foams. Bio‐foams had lower thermal degradation temperatures in the urethane degradation due to natural molecular chains with lower thermal stability than petroleum skeletons. However, these foams had good thermal degradation at a high temperature stage because of MDI polyurea prepolymer, which had superior thermal stability than toluene diisocyanate adducts in petroleum‐based PU foams. In addition, soy‐based polyol, with high hydroxyl value, contributed PU foam with superior tensile and higher elongation, but lower compressive strength and modulus. Nonetheless, bio‐foam made with high hydroxyl valued soy‐based polyol had smaller and better distributed cell size than that using low hydroxyl soy‐based polyol. Soy‐based polyol with high hydroxyl value also contributed the bio‐foam with thinner cell walls compared to that with low hydroxyl value, whereas, petroleum‐based PU foams had no variations in cell thickness and cell distributions.

Thermal Stability Analysis of Polyurethane Foams Made from Microwave Liquefaction Bio-Polyols with and Without Solid Residue

“…The bands at 1507 cm -1 and 1596 cm -1 were derived from aromatics of pMDI (Li et al 2013). The peaks at 2915 cm -1 and 1410 cm -1 were attributed to methylene and the aromatic rings, respectively (Gu et al 2012;Zhao et al 2012). An excessive amount of pMDI at 2275 cm -1 was used deliberately to ensure that hydroxyl components could completely react with NCO groups.…”

Equilibrium and kinetic mechanisms of woody biochar on aqueous glyphosate removal

“…This peak have shifted to 3422 cm À1 after adsorption suggesting that chemical interactions occurred between glyphosate molecule and phenolic groups in dendro biochar. The peaks at 1799 and 1089 cm À1 in bare biochar were assigned to CeOeC stretching vibrations (Gu et al, 2012). Amides (eNH 2 ) in biochar surface can be distinguished by the peak present at 1429 cm À1 (Devi and Saroha, 2013).…”

Recent Advancement in Plant Oil Derived Polyol‐Based Polyurethane Foam for Future Perspective: A Review

“…investigated the effect of ethylene glycol on the properties of soya polyol based PUFs. Gu et al . synthesized PUF by crude soybean oil based polyol by epoxidation followed by ring‐opening reaction.…”