GB/T 13477.15-2017Test method for building sealants -- Part 15: Determination of adhesion/cohesion properties after exposure to heat and artificial light through glass and to water (English PDF)

6.1 Glass substrate: A glass plate that complies with the provisions of 4.2 in GB/T

13477.1-2002, with a thickness of 6 mm, and is used to prepare specimens. Each

specimen consists of two glass plates, and the cross-sectional dimensions are shown in

Figure 1. Test substrates of other sizes can also be used, but the bonding area of the

sealing material shall be the same as shown in Figure 1.

6.2 Spacer block: The surface shall be anti-adhesive and used to prepare a sealing

material specimen with a cross-section size of 12 mm×12 mm (see Figure 1).

6.3 Bond breaker: Anti-adhesive film or anti-adhesive paper, such as polyethylene (PE)

film, is used to prepare specimens. It should be selected according to the

recommendations of the sealing material manufacturer.

6.4 Blast drying oven: The temperature can be adjusted to (70±2) °C, used for

processing specimens according to method B (see 8.3).

6.5 Container: It is filled with deionized water or distilled water, and used for soaking

the specimen during processing according to method B (see 8.3).

6.6 Test chamber with artificial light source: It can expose the specimen to a light source

under dry conditions at the specified temperature (that is, the temperature measured by

the black standard thermometer). The test chamber shall be fully ventilated, and the

light can be directly irradiated on one surface of the glass substrate. (see Figure 1).

If fully automated equipment is used, the water exposure test can be carried out in the

same test chamber. It can be either immersed in water or sprayed, but deionized water

shall be used. For cyclic exposure test equipment with a spray system, see GB/T

16422.2-2014.

nm~400 nm, the average irradiance on the surface of the specimen is (60±2) W/m2; or

when the wavelength is 340 nm, the irradiance is 0.51 W/(m2 · nm).

6.8 Black standard thermometer: It shall comply with the provisions of 4.4 in GB/T

16422.2-2014. Black panel thermometers may also be used, which under given

operating conditions will indicate a lower temperature than a black standard

thermometer. The temperature difference between the two measurements may be as

much as 10 °C.

Readings can only be taken after sufficient time has elapsed for the temperature to

become more stable. Temperature can also be controlled, for example by adjusting the

air velocity.

6.9 Tensile testing machine: It is equipped with a recording device and capable of

stretching the specimen at a speed of (5.5±0.7) mm/min.

6.10 Positioning block: It is used to control the width of the stretched specimen,

allowing the specimen to maintain an elongation rate of 60%, 100% of the initial width,

or the width agreed upon by all parties.

6.11 Measuring tool: The graduation value is 0.5 mm.

9.2.2 Automatic cycling

The standard conditions of the test are as follows: a total exposure time of 500 h, 250

cycles, and each cycle is 120 min; each cycle includes:

a) Drying period (102 min): During this period, the specimen is exposed to light

and heated. Starting from the drying period, increase the temperature until it

reaches the stable black standard temperature of (65±3) °C;

b) Wet period (18 min): Spraying or soaking in water can be used, and the water

temperature is (25±3) °C. The light source can be turned off during the wet

period.

9.2.3 Manual cycling

Manually transfer the specimen between the dry test chamber and the wet test chamber.

At this time, water immersion shall be used during the wet period. Mark any surface of

the specimen to ensure that the same surface is always exposed.

The specified test conditions are as follows: 168 hours per cycle, and a total exposure

time of 3 cycles of 504 hours; each cycle includes:

a) Drying and wet exposure period (5 d): immersion in water of (25±3) °C for 5

h and then exposure to light for 19 h at the black standard temperature of

(65±3) °C every day;

b) Drying exposure period (2 d): exposure to light for 48 h at a black standard

temperature of (65±3) °C.

9.3 Tensile test

After the artificial climate cyclic exposure test, the specimen is stored under standard

test conditions for 24 hours.

Place the specimen into the tensile testing machine and stretch the specimen at a speed

of (5.5±0.7) mm/min. The tensile elongation rate is 60% or 100% of the initial width

(stretched to 19.2 mm or 24 mm respectively), or the width agreed upon by all parties;

use the positioning block (6.10) to fix the stretched specimen and keep it at (23±2) °C

for 24 h.

Remove the positioning block, check the adhesion/cohesive failure of the specimen,

and use a measuring tool with a graduation value of 0.5 mm to measure the depth (mm)

of adhesion/cohesive failure.

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