CONTINUOUS POLYMER REACTOR DESIGN FOR PREPREG EPOXY MATRIX PREPOLYMERS

摘要

A twin screw extruder was used to synthesize the commercial Narmco 5208 prepolymer for usernon a prepreg line. Narmco 5208 is widely used in the aerospace industry and consists of threerncomponents: 4, 4’-diaminodiphenylsulfone (44DDS), N, N, N’, N’-tetraglycidyl-4, 4’-rndiaminodiphenylmethane (TGDDM), and 4-[2-(4-hydroxyphenyl) propan-2-yl] phenol (SU-8).rnThe reaction was first examined in a batch reactor to analyze cure kinetics and to obtain a targetrnglass transition temperature (T_g) at which the epoxy prepolymer could be successfully processedrninto prepreg. Reactive extrusion was then performed at varying processing conditions to obtainrnthe target T_g. A design of experiments was also used to study the effect of processing conditionsrnon epoxy prepolymer properties. Processing conditions include barrel temperature, screw speed,rnand throughput. Differential scanning calorimetery, dynamic mechanical analysis, near-infraredrnreflectance spectroscopy, and mechanical testing were performed to characterize prepolymerrnproperties for batch and continuous reactor conditions. A comparison of the batch andrncontinuous reactor processes was used to assess the viability of using the continuous reactorrnprocess in epoxy prepolymer for the prepreg line.