| 摘要 |
<p>Composite articles are prepared by resin transfer molding and an applied gas pressure during heating. A mass of reinforcement is placed into a mold (22), and the mold (22) is evacuated. A resin source (36) is connected to the mold (22), and thermosetting resin is introduced into the mold (22) from the source (36). A gas pressure source (44) is connected to the mold (22), and an external column (40) of resin is maintained in the gas pressure line (46). The mold (22) is heated to set and cure the resin within the mold (22), but the resin in the external column (40) is maintained in an unset condition. After the resin is introduced into the mold (22) and simultaneously with the heating of the resin, a gas pressure is applied to the column (40) of liquid resin, preferably at a pressure greater than the vapor pressure of water at the temperature to which the resin is heated, to prevent gas evolution to form bubbles during setting and curing and to minimize the volume of any bubbles already present in the resin from other sources.</p> |
