Producing an open-cell crosslinked polyolefin foam comprises cooling a closed-cell crosslinked polyolefin foam below the embrittlement temperature of the polyolefin and mechanically stressing the foam

摘要

Producing an open-cell crosslinked polyolefin foam comprises cooling a closed-cell crosslinked polyolefin foam below the embrittlement temperature (Te) of the polyolefin and mechanically stressing the foam to open the cells. Independent claims are also included for: (1) apparatus for opening the cells of a closed-cell crosslinked polyolefin foam, comprising a housing in which a liquid coolant is kept at a constant level, a device for feeding a foam web into the housing above the liquid level, a device for guiding the web within the coolant, an outlet opening above the liquid level for withdrawing the web from the housing, and a pair of rolls for mechanically stressing the web; (2) open-cell crosslinked polyolefin foam produced as above with a largely undamages skin on both sides.