title: Bio-based alternative to the diglycidyl ether of bisphenol A with controlled materials properties.
abstract: A series of biobased epoxy monomers were prepared from diphenolic acid (DPA) by transforming the free acid into n-alkyl esters and the phenolic hydroxyl groups into diglycidyl ethers. NMR experiments confirmed that the diglycidyl ethers of diphenolates (DGEDP) with methyl and ethyl esters have 6 and 3 mol % of glycidyl ester. Increasing the chain length of DGEDP n-alkyl esters from methyl to n-pentyl resulted in large decreases in epoxy resin viscosity (700-to-11 Pa·s). Storage modulus of DPA epoxy resins, cured with isophorone diamine, also varied with n-alkyl ester chain length (e.g., 3300 and 2100 MPa for the methyl and n-pentyl esters). The alpha transition temperature of the cured materials showed a linear decrease from 158 to 86 °C as the ester length increases. The Young's modulus and tensile strengths were about 1150 and 40 MPa, respectively, for all the cured resins tested (including DGEBA) and varied little as a function of ester length. Degree of cure for the different epoxy resins, determined by FTIR and DSC, closely approached the theoretical maximum. The result of this work demonstrates that diglycidyl ethers of n-alkyl diphenolates represent a new family of biobased liquid epoxy resins that, when cured, have similar properties to those from DGEBA.
authors: New York State Center for Polymer Synthesis, Department of Chemistry and Chemical Biology, Rensselaer Polytechnic Institute , 110 Eighth Street, Troy, New York 12180, United States.
authors: Anthony
authors: A
authors: Maiorana
authors: Stephen
authors: S
authors: Spinella
authors: Richard A
authors: RA
authors: Gross
mesh_terms: D001559:Benzhydryl Compounds / Q000737:chemistry*; D055119:Elastic Modulus; D004853:Epoxy Resins / Q000737:chemistry*; D010636:Phenols / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared; D013718:Tensile Strength; D013818:Thermogravimetry; D044366:Transition Temperature; D014783:Viscosity; D000098826:Bisphenol A Compounds
chemical_list: D001559:Benzhydryl Compounds; D004853:Epoxy Resins; D010636:Phenols; C006780:bisphenol A; D000098826:Bisphenol A Compounds