Industry Terms General PSI Pounds per square inch. Weatherability The ability of a polymer to withstand the delete rious effects of UV radiation and other atmospheric conditions. Environmental Stress Cracking The formation of cracks or crazing caused by exposure of articles to certain chemicals or stresses. (ASTM D-1693) Melt Index (MI) The amount of a thermoplastic resin, measured in grams, which can be forced through a 0.0825" orifice in ten minutes at a specified temperature and with specified force. Specific conditions have been established for various resins. (ASTM D-1238) Specific Gravity (SpG) Specific Gravity is the ratio of a given volume of material at 73.4ºF to that of an equal volume of water at the same temperature, i.e., if the specific gravity is more than 1.0, it sinks, if less than 1.0, it floats. (ASTM D-792) Density Weight per unit volume, usually expressed in grams per cubic centimeter or in pounds per cubic foot. Water has a density of 62.5 pounds per cubic foot. Bulk density is a term for apparent density of a material in a powered state. Conversion
A. English to Metric Conversions Symbol When You Know Multiply By To Find Symbol In Inches 2.54 Centimeters Cm Ft Feet 30 Centimeters Cm Yd Yards 0.9 Meters M Mi Miles 1.6 Kilometers Km Oz Ounces 28 Grams G Lb Pounds 0.45 Kilograms Kg
B. Metric to English Conversions Symbol When You Know Multiply By To Find Symbol Mm Millimeters 0.04 Inches In Cm Centimeters 0.4 Inches In M Meters 3.3 Feet Ft M Meters 1.1 Yards Yd Km Kilometers 0.6 Miles Mi G Grams 0.035 Ounces Oz Kg Kilograms 2.2 Pounds Lb