Acrylic Rigid Vinyl Polycarbonate
Index of Refraction 1.49 1.54 1.586
Tensile Modulus (103 PSI) 325-470 350-600 345
Flexural Modulus (103 PSI) 390-470 300-500 340
Hardness M80-M100 (Rockwell) D65-85 (Shore) M70-M72 (Rockwell)
Thermal expansion (10-6/°C) 76 76 68
Service Temp., °C 80 70 120
Specific gravity 1.19 1.45 1.20
Effect of sunlight none yellows yellows slowly
Physical properties of some materials available from Fresnel Technologies, Inc.