Abstract: Thermoplastic polymers, rubbery polymeric components and reinforcing fillers are mixed and heated to a range of 380° F. to 440° F. The resulting mixture is then fed into a BANBURY mixer, with the resulting mixture fed into a diverter feeding two molds. The velocity of the piston of each mold being filled is controlled to thereby control the density of the molded product along its length (BANBURY is a registered trademark of Farrel Corporation). As each mold is filled, it is deposited in a cool water bath (50° F.–60° F.) while the next mold is being filled. The molds are sequentially transferred to an air cooling rack to complete the process. A texture, generally comprising indentations perpendicular to the longitudinal axis on the molded object, provides a frictional surface between the railway crosstie and the ballast beneath the crosstie.

Abstract: Polymeric composites are described that can be formed into articles of construction to replace similar articles formed of wood and concrete. The composites comprise a polymer component comprising polyolefins preferably obtained as waste or recycle; a rubbery polymeric component preferably obtained from disposed tires; and a reinforcing filler component comprising mica. The mica is preferably of the expanded variety to allow for a reduction in density over similar composites containing traditional mica. The evaporation of volatile compounds initially contained within the different components, primarily the rubbery polymeric component, allows for the production of articles of construction having a foamed inner core in which the foamed cell structure has not been achieved through the use of traditional CO.sub.2 generating foaming agents. Processes for forming the articles of construction are provided that include both extrusion and molding techniques.