摘要 |
The present invention is a method to manufacture shaped foam article. Specifically, the present invention is a method of extruding a styrenic polymer with a blowing agent to form a foam polymer plank having a density gradient and shaping the surface of the foam plank having the lowest density by passing the foam plank through one or more sets of rolls. Preferably, the foam has a vertical compressive balance (Rv) equal to or greater than 0.4 and more preferably, the foam has a cell gas pressure less than 1 atmosphere and/or an open cell content of equal to or less than 20 percent.
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