Numerical Selection of the Parameters in Producing Microcellular Polymethyl Methacrylate with Supercritical CO ₂

A systematized calculation of foaming parameters in producing microcellular polymethyl methacrylate (PMMA) with supercritical carbon dioxide (SCCO ₂ ) was proposed. The calculated optimal results were saturation temperature = 313 K, pressure = 25 MPa and time = 15 h, which were achieved by the Chow model, classical nucleation theory and Fick diffusion law, respectively. Additionally, the Center-Composite Design (CCD) statistical approach in Response Surface Method (RSM) was employed to evaluate the validity of the calculated parameters. The error between the optimal parameters predicted by CCD statistical approach and the calculated ones was acceptable, demonstrating the accuracy of the calculated parameters.