초록 ▼

A process for preparing a cellular polymer containing perforated cell windows in the presence of a perforating agent being a substance that has a critical surface free energy of less than about 23 mj/m2 is disclosed. The cellular polymers obtained according to this invention have a fine cell structu

A process for preparing a cellular polymer containing perforated cell windows in the presence of a perforating agent being a substance that has a critical surface free energy of less than about 23 mj/m2 is disclosed. The cellular polymers obtained according to this invention have a fine cell structure and show enhanced dimensional and thermal insulation stability. The invention also relates to rigid polyurethane foam prepared in the presence of, for example, particulate poly(tetrafluoroethylene) or a liquid polyfluoro- or perfluorocarbon, with a boiling point of at least 130°C., as perforating agent.

대표청구항 ▼

A process for preparing a cellular thermoset polyurethane polymer containing perforated cell windows by reacting an organic polyisocyanate with a substance containing one or more isocyanate-reactive hydrogen atoms/molecule in the presence of a perforating agent and a blowing agent wherein: the perfo

A process for preparing a cellular thermoset polyurethane polymer containing perforated cell windows by reacting an organic polyisocyanate with a substance containing one or more isocyanate-reactive hydrogen atoms/molecule in the presence of a perforating agent and a blowing agent wherein: the perforating agent, present in from about 0.01 to about 1.0 percent based on total weight of polymer, is a solid substance that has a critical surface free energy of less than about 23 mJ/m2 and an average particle size of about 20 microns or less; the blowing agent comprises water; and the isocyanate-reactive substance is a polyether polyol, polyester polyol, amine-terminated polyether, or mixtures thereof.