2. Physical requirements:

a. Water absorption: Materials shall not have more than 0.5 percent retained water by weight when tested in accordance with the requirements of ASTM D570, Procedure A.

 

B. Softening point: Materials shall have a softening point of at least 194 degrees F as determined in accordance with the requirements of ASTM E28.

 

C. Specific gravity: The specific gravity of the thermoplastic compound at 77 degrees F shall be from 1.7 to 2.2.

 

D. Impact resistance: Impact resistance shall be at least 10 inchpounds at 77 degrees F after material has been heated for 4 hours at 400 degrees F and cast into bars of 1 inch cross-sectional area, 3 inches long and placed with 1 inch extending above the vise in a cantilever beam, Izod-type tester, conforming to the requirements of ASTM D256, using the 25 inchpound scale.

 

E. Drying time: Material shall set to bear traffic in not more than 2 minutes when the road temperature is 50 degrees F or above.

 

F. Durability and wear resistance: Material shall be designed to provide a life expectancy of at least 5 years under an average daily traffic count per lane of approximately 9,000 vehicles.

 

G. Glass beads: Glass beads shall conform to the requirements of Section 234.

 

H. Flashpoint: The material flashpoint shall be no less than 500 degrees F when tested in accordance with the requirements of ASTM D92.

 

Storage life: the anterial shall meet the requirements of this specification for a period of one year.