Synthesis and copolymerization of thermosetting resins obtained from vegetable oils and biodiesel-derived crude glycerol

• Crude glycerol was used in the synthesis of vegetable oil based thermosetting resins.
• Resins were copolymerized with styrene, affording rigid materials.
• Properties of castor oil thermosets were in the range of commercial UP.
• Materials obtained from both resins were stable below 200 °C.
• Radical homopolymerization of both resins afforded viscous liquids.

Alkaline crude glycerol from biodiesel production was used in the synthesis of soybean oil and castor oil-based polyols through glycerolysis reaction. These polyols were further converted into highly active unsaturated resins through maleinization reactions. The resins were copolymerized with styrene (10–50 wt%) using cobalt octoate and methyl ethyl ketone peroxide (MEKP) at 40 °C, affording rigid materials. Materials were characterized by FTIR spectroscopy, Soxhlet extraction, TGA, DMTA, and mechanical tests. Tg values of 72–152 °C and elastic modulus of 465–2945 MPa were obtained, depending on the type of resin and styrene concentration.The materials presented flexural modulus and flexural strengths in the range of 246–1716 MPa and 24–89 MPa respectively. Tg values and elastic modulus at 25 °C were higher for materials obtained from castor oil glycerides. Materials obtained from both resins were stable under 200 °C. Higher thermal stabilities were obtained for castor oil based materials. These properties were related to a higher crosslinking density obtained for polymers derived from castor oil. In addition, radical homopolymerization of both resins at 100 °C during 24 h afforded viscous liquids with Mn values between 1358 and 3775.

Figure optionsDownload as PowerPoint slide