Optimization of cure kinetics parameter estimation for structural reaction injection molding/resin transfer molding

Abstract

A numerical method is proposed for polymer kinetic parameter estimation of either Structural Reaction Injection Molding (SRIM) or Resin Transfer Molding (RTM). The method simulates either radial flow or axial flow of reactive resins through a fiber preform inside a mold cavity. This method considers a non‐isothermal environment with different inlet boundary conditions. Based on the molding conditions, this method can find the best values of chemical kinetic parameters by comparing the simulated temperature history and the experimental temperature history. Since the kinetic parameters are estimated with the real molding conditions, the simulations using these parameter values can have better agreement with molding data than those parameters which are obtained from idealized conditions such as Differential Scanning Calorimeter (DSC). The optimization approach was verified by estimating kinetics parameters for RTM data available in the literature. Temperatures predicted by the optimized kinetics parameters are compared with experimental data for two different molding conditions: injection of a thermally activated resin into a radial mold under constant pressure flow, and injection of a mix activated resin into a radial mold under constant volume. In both cases, the optimized kinetics parameters fit the temperature data well.

A Numerical Study of Nonisothermal Reactive Flow in a Dual-Scale Porous Medium Under Partial Saturation

“…(19), (22), and (23), and are responsible for calculating velocities V,, and V, in the outer and inner regions, respectively. A staggered grid approach similar to the SIMPLE of Patankar [29] is adopted in which the pressures P,, is solved at the center of outer CVs, and the velocities K, and Vj are solved at the faces of control volumes.…”

“…The source term can be expressed as SI, -V^R^Er^ [22]. where J^a is the volume of the resin within the CV, R^ is the rate of curing reaction for the resin, and £« is the heat of reaction \m unit volume.…”

“…In the conventional single-scale cure transport model [16,22], the highest cure is expected to be near the macrofront during this 1-D mold-filling simulation, since the older, more cured resin is continually pushed forward by the newer. less cured resin.…”

“…= 8816.7 J/mole, «] = 2.59, and «2 = 1-17. These parameters are borrowed from earlier publications[22] and[23].…”

Research on Curing Processes in RTM by FEM

“…for example, high demand for RTM resin or strict preparation requirements for the mold and the fiber preform.Fiber preform requires high permeability. The material structure and product performance changes during the curing process is not clear and so on [1][2][3][4][5][6][7].…”