Abstract: The present invention relates to an extruded fluoropolymer-acrylic composite and a method of producing same. The extruded product of the present invention comprises a layer of at least one first polymeric substance comprising a mixture of: (1) from about 1 to about 70 percent by weight of at least one acrylic material, (2) at least one fluoropolymer, and (3) at least one inorganic pigment in sufficient amount to render the first polymeric substance reflective to infrared light and opaque to both ultraviolet light and light and light having a wavelength of about 350 to about 2500 nanometers; in contact with a layer of at least one second polymeric substance being of a chemical character so as to be amenable to adhesion to the at least one first polymeric substance in the extrusion product. The preferred embodiment of the invention method is conducted under vacuum.

Abstract: Two environmental test zones at different temperatures are separated by an insulated wall. A portion of the wall is rotatable and is designed to hold a test specimen thereon. By rotating this portion of the insulated wall, the specimen is exposed to different temperature zones in recurrent cycles. The two temperature zones are readily separable for ease in removing and installing test specimens.