Outdoor Exposure Conditions

The exposure test was carried out at three sites in Japan. The exposure condi­tions and a summary of the weather indicators at the exposure sites are given in Tables 2 and 3, respectively. The test specimens were exposed to both static and dynamic conditions, i. e., the static condition was without any movement and the dynamic condition exposed the specimen to extension and compression cycles that were periodically reversed once every month. The evaluation of sur­face degradation on the specimen was determined at four locations on the sealant surface, i. e., for the statically exposed specimens at ±0 % movement amplitude, and for the dynamically exposed specimens at ±1.5 %, ±15 %, and ±25 % movement amplitude. The center of the dynamically exposed specimen was undergoing a movement of ±1.5 % due to the offset between the rotary pin and the edge of the specimen.

TABLE 2—Exposure conditions.

Location of Exposure

Term of Exposure

Direction/

Angle

Interval of

Extension/Compression

Exchange

Position of Evaluation

North

None (Static)

±0 %

Oct. 1, 2002

±1.5 %

Central

South/45°

Twice/week

± 15 %

Sept. 31, 2006

(Dynamic)

South

± 25 %

TABLE 3—Summary of weather indicators.11

North

Central

South

Temperature

Max.

33.6

28.8

33.1

(°C)

Min.

-25.5

-2.1

13.5

Ave.

6.6

14.2

23.7

Accumulated total solar

radiation

(0° – M/Jm2)

16,962

20,345

22,694

Accumulated precipitation (mm)

3,994

7,156

8,392

aTerm: Oct. 1, 2002 to Sept. 31, 2006.