A novel high performance bismaleimide/diallyl bisphenol A (BMI/DBA)–epoxy interpenetrating network resin for rigid riser application
Abstract
A new class of interpenetrating network (IPN) resin system was developed by mixing tetrafunctional epoxy resin (TGDDM) with diallyl bisphenol A (DBA) modified bismaleimide (BMI) for rigid riser applications at high temperatures of more than 280 °C. The curing kinetics of the resins were assessed by differential scanning calorimetry (DSC). Epoxy resin with DBA modified BMI (BMI/DBA–epoxy IPN) showed low activation energy which is due to the autocatalytic effect of DBA modified BMI in the curing process. The thermal stability of the cured resins as evaluated using thermogravimetric analysis (TGA) showed that they were stable up to 325 °C. Dynamic mechanical analysis (DMA) showed that the BMI/DBA–epoxy IPN resin had a glass transition temperature (Tg) equal to that of neat epoxy of around 280 °C. The incorporation of DBA modified BMI into the epoxy resin enhanced the mechanical properties such as tensile, flexural and impact strength by 25%, 30% and 45%, respectively compared to neat epoxy resin. Furthermore, the viscosity of the IPN was 0.3–1 Pa s which is within the filament winding range required for rigid risers. Prototype rigid risers were made using the BMI/DBA–epoxy IPN resin as matrix and carbon fiber as the reinforcement using the filament winding technique. The approach presented here represents a good approach to developing high performance high thermal stability resins for rigid risers in oil field applications.