ASTM International Standard Classification System for Poly(Methyl Methacrylate) (PMMA) Molding and Extrusion Compounds ASTM D788-16

The purpose of this classification system is to provide a method of adequately identifying poly(methyl methacrylate) (PMMA) molding and extrusion compounds. These compounds are polymers based on methyl methacrylate, and at least 70 % of the polymer shall be polymerized from methyl methacrylate. Poly(methyl methacrylate) molding and extrusion compounds are classified into groups in accordance with their composition. These groups are subdivided into classes and grades: class 1, 2, 3, and 4; grade 1 - materials used where special ultraviolet transmission, filtering, or stabilization characteristics are not required, grade 2 - materials used for those specialized applications in which the greatest amount of transmission of UV light is required, and grade 3 - materials (transparent UV stabilized or transparent UV absorbing) used when either special resistance to slight color change over long exposure times or high-intensity UV radiation is required, or when the material is required to filter out ultraviolet light. The plastics composition shall be uniform and shall conform to the requirements specified.