초록 ▼

Disclosed is an extruded, open-cell microcellular alkenyl aromatic polymer foam useful in insulating applications. The foam has an open cell content of about 70 percent or more. The foam has an average cell size of about 70 micrometers or less. The foam is particularly useful in evacuated or vacuum

Disclosed is an extruded, open-cell microcellular alkenyl aromatic polymer foam useful in insulating applications. The foam has an open cell content of about 70 percent or more. The foam has an average cell size of about 70 micrometers or less. The foam is particularly useful in evacuated or vacuum insulation panels. Further disclosed is a process for making the open-cell foam.

대표청구항 ▼

A process for making an extruded, open-cell microcellular alkenyl aromatic polymer foam having an open cell content of about 70 percent or more and having an average cell size of about 70 micrometers or less and a density of about 16 to about 100 kilograms per cubic meter, comprising: a) heating an

A process for making an extruded, open-cell microcellular alkenyl aromatic polymer foam having an open cell content of about 70 percent or more and having an average cell size of about 70 micrometers or less and a density of about 16 to about 100 kilograms per cubic meter, comprising: a) heating an alkenyl aromatic polymer material comprising more than 50 percent by weight alkenyl aromatic monomeric units to form a melt polymer material; b) incorporating into the melt polymer material an amount of a nucleating agent additive at from about 0.01 to about 5 parts by weight based upon the weight of the polymer material; c) incorporating into the melt polymer material at an elevated pressure to form a foamable gel a blowing agent of which about 50 mole percent or more is selected from the group consisting of 1,1-difluoroethane, 1,1,1-trifluoroethane, 1,1,1,2-tetrafluoro-ethane, chlorodifluoromethane, carbon dioxide, and mixtures of any of the foregoing based upon the total number of moles of blowing agent, the blowing agent being incorporated at about 0.06 to about 0.17 gram-moles per kilogram of polymer material; d) adjusting the foamable gel to a foaming temperature sufficient to form a foam having 70 percent or more open cell content; and e) extruding the foamable gel through a die into a region of lower pressure to form the foam.