In this paper we tried to use nano particles to improve the mechanical properties of Polymethacrylimide (PMI) foam. PMI is closed cell foam used as insulation with superior mechanical properties. The monomers used in this research were Acrylonitrile (AN), Methacrylic acid (MAA), Methacrylonitrile (MAN), Acrylamide(AA). Azobisisobutyronitrile (AIBN) as the thermal-sensitive initiator, 2-Propanol (2-p) as the foaming agent and Nanowire D4C as nanoparticle were used. The materials were mixed and dissolved together with 3 different formulations and then copolymerized via the mode of bulk casting in the water bath. Expandable copolymer boards were foamed by chemical foaming in hot oven. Mixture 1 was mixed of AN, MAA, MAN, AIBN and 2-p. Mixture 2 was mixed like 1 but with AN instead of MAN. In mixture 3 nanowire added to mixture 2. The tests were used to examine thermal properties were DSC and TGA. These tests showed enhanced thermal properties of foam by nano particle addition. Furthermore different chemical structure was predicted because, exothermic pick at 190 °c changed to endothermic peak at 260 °c. Mechanical properties investigated by compressive strength test and DMA which both showed increased properties by nano addition to PMI foam.