PLASTICS. PRIMARY MATERIALS FOR POLYURETHANES. POLYESTERS, POLYETHERS AND ISOCYANATES. VISUAL ASSESSMENT OF COLORATION IN GARDNER UNITS.

• 塑料。聚氨基甲酸酯塑料。聚酯。聚醚和异氰酸盐。加德纳单位颜色目视法测定。