The density * of the foams was obtained by dividing their measured weight by their volume. Their compression behavior was investigated at room temperature using a Universal Testing Machine (UTS Test System, Germany) equipped with a 1000-N load cell. The measurements were made at a crosshead speed of 0.5mm/ min on cylindrical specimens with a height of 10mm and a diameter of 20mm machined from the foams with their axis parallel to that of the autoclave molds. The compression modulus E L was evaluated from the initial linear region of the stress–strain curves. Three to five specimens were tested for each material and each set of processing conditions.