Non-aldehyde resins based on resorcinol and natural alkylresorcinols modified with styrene

Abstract

Abstract The use of natural alkylresorcinols produced in Estonia (5-methylresorcinol, HONEYOL80 fraction) instead of the expensive resorcinol reduces the cost of the synthesized resins while maintaining their high technological characteristics. Resins based on resorcinol (R), 5-methylresorcinol (5-MR), HONEYOL80, dicyclopentadiene (DCPD), and styrene (S) were synthesized in the presence of an acid catalyst. Their physical and chemical characteristics have also been studied. It was shown that depending on the mole ratio of the components of the formulation, resins with different softening temperatures (66 to 97 °C), ash content of 0.04 to 0.39 wt%, and a low content of volatile components at 105 °C, including moisture, were obtained. The best conditions for the synthesis of resins with a softening point of 94 °C–97 °C are molar ratio of R (5-MR): DCPD: S = 1: 0.5: 0.3 at temperature 135 °C–170 °C, synthesis time 5 h 30 min. The synthesized resins did not require additional processing under a vacuum. The presence of unreacted resorcinol and 5-methylresorcinol (quantitatively and qualitatively) in the final product, the homogeneity, and molecular weight characteristics of the resin composition (qualitatively) were determined by TLC and GPC.