Unsaturated polyester resins for thermoset applications using renewable isosorbide as a component for property improvement

Unsaturated polyester (UPE) resins are used in a variety of thermosetting applications due to the reduced cost when compared to epoxy resins; however, UPE resins also have reduced thermomechanical performance. Investigating avenues to improve the performance of UPEs has led to the use of bio-based starting materials as structural components of the synthesized prepolymers as a result of their advantageous structural features. Isosorbide, a compound derived from renewable feedstocks, has been utilized to provide additional stiffness from the diol component for novel unsaturated polyesters resins. These resins have been shown to possess T-g's (32-72 degrees C) and storage moduli (540-2200 MPa) that are in the desired range for composite materials with viscosities (1.2-25 Pa s) amenable to a variety of liquid molding techniques. (c) 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42315.