Thermal and mechanical properties of cast polyurethane resin based on soybean oil

Abstract

The soy polyols were prepared from epoxidation of soybean oil followed by ring opening of oxirane obtained by using methanol as the ring opener. Polyols of hydroxyl (OH) numbers ranging from 128 to 174 mg of KOH/g were obtained by the variation of epoxidation time of soybean oil. A novel cast polyurethane resin has been synthesized by these polyols and 2,4-toluene diisocyanate. Swelling of networks in toluene showed that the sol fraction varies from 1.13 to 72.06%. The thermal and mechanical properties of cast resins were characterized by differential scanning calorimetry and thermogravimetric analysis. The results showed that the glass transition temperature increases with the increase of OH number and that the thermal stability of the resins was slightly decreased with the increasing OH number. The tensile strength at break increases with the increase of OH number. Polyols with OH number of 174 mg of KOH/g gave glassy polymers, whereas those below this value gave rubbers.

Synthesis and characterization of novel polyurethane acrylates based on soy polyols

“…The PUs were synthesized from three polyols with IPDI using the method reported previously 25, 26. The PUs derived from Polyol‐173, Polyol‐205, and Polyol‐248 are designated as PU173, PU205, and PU248, respectively.…”

“…Herein, three polyols based on epoxidized soybean oil (ESO) were prepared by oxirane ring opening with methanol, glycol, and 1,2‐propanediol. PUs were obtained from these soy polyols with isophorone diisocyanate (IPDI) 25–27. Furthermore, the prepolymers from polyols with IPDI were end capped by hydroxyethylacrylate (HEA) to form PUAs through a thermal polymerization process.…”

Castor oil‐based polyurethane/silica nanocomposites: Morphology, thermal and mechanical properties

“…The neat PU was prepared from the castor oil with IPDI using previously reported methods . The bio‐based PU nanocomposites with 6 and 12 wt% different nano‐silica were prepared as follows: three nano‐silicas (SiO 2 , KH560‐SiO 2 and KH570‐SiO 2 ) were dispersed in dry acetone by ultrasonication (60 min, 250 W).…”

Thermal, mechanical, and morphological properties of functionalized graphene‐reinforced bio‐based polyurethane nanocomposites

“…Polyol‐based epoxidized soybean oil containing 6.3% oxygen was prepared by oxirane ring opening with phosphoric acid and the hydroxyl number of the polyol was 207 mg KOH/g. The neat PU was prepared by mixing the polyol with IPDI using an isocyanate index of 110 according to previously reported methods . The mixture was stirred for 2 min and poured into a polytetrafluoroethylene mold, which was left under vacuum to evacuate bubbles and then thermally treated respectively at 90°C for 2 h, 110°C for 24 h to complete the reaction.…”