Investigation on mechanical properties and thermal expansibility of epoxy resin copolymerization modified cyanate ester under medium‐low temperature curing process

Abstract In this paper, the mechanical properties and thermal expansibility of cyanate resin (CE) copolymerization modified by epoxy resin (EP) under medium‐low temperature curing process were studied. The curing temperature of the modified resin was analyzed, and the results showed that the initial curing temperature of the copolymerization resin was reduced by 87°C compared with the blend resin and further reduced when dibutyltin‐dilaurate was used. The results of mechanical properties test showed that the tensile and bending strength of the modified resin were the highest, which were 55.5 and 97.3 MPa, respectively. The results of scanning electron microscopy showed that the modified resin with 80 wt% cyanate content had the coarsest tensile and bending sections, the largest number of fracture stripes and rich layers, so it had relatively better toughness. The linear thermal expansion coefficient (CTE) of modified resin was determined and the results showed that when the loading of cyanate was 80 wt%, the CTE of the modified resin reached the lowest, only 6.36 × 10 −5 °C −1 .