QUV test

Test procedure Oil soot, QUV test. Sulfuric acid. Cleaning agent. 

Test procedure Oil soot, QUV test. Sulfuric acid, 72 h RT 1000 h 10% 72 h RT Test result No change No change No change of 

Figure 11.6. QUV-A weatherometer testing (75-p.m sample thickness) relationship of days to failure (50% elongation) to carbon black type and loading.

Figure 1. QUV (UVB 313 Light Source) Test Data. Pigmented, Filled Plasticized PVC Sheets Containing DIDP, 71 IP or Blends of the Two.

Figure 19 (A) QUV/cw, cool white photostability tester (B) a cross sectional view of the test chamber before modification for pharmaceutical testing and (C) their tablet sample holder tor the unit. Source. Courtesy of Q-Lab Corporation.

It is also possible to test the resistance to humidity by submitting bonded samples to an accelerated weathering tester such as the QUV spray tester, which combines water spray and condensation plus UV light to simulate sun rays. We will study this in the Weathering section hereunder. 

Q-Lab (formerly Q-Panel) (34) offers a fluorescent lamp photostability-testing unit, their QUV/cw unit, pictured in Figure 19. This unit, originally designed 

Figure 22.6. Accelerated weather testing, (a) Xenon arc Fade-Ometer. (Courtesy of Atlas Electric Devices Company.) (b) Fluorescent lamp QUV accelerated weathering tester. (Courtesy of Q-Panel Company.) (c) Xenon arc Weather-Ometer. (Courtesy of Atlas Electric Devices Company.)

Paint grade cerium sulfide pigments exhibit very good durability in both the xenon test and outdoor exposure. In QUV-A testing, however, the humidity conditions of the experiment are too severe to be representative of outdoor exposure. 

Figure 2. Light stability of a high-solids, one-coat silver metallic paint based on a two component polyurethane. Test criterion gloss retention QUV irradiation. (HALS) Bis-(2,2,6,6-tetramethyl-piperidinyl-4)sebacate (UVA) 2-(2 -hydroxy-3, 5 -di-tert-amylphenyl) benzotriazole.

The fluorescent ultraviolet lamp and condensation (fluorescent UV) test utilized UVA-340 lamps as defined in ASTM G154 [14]. The cycle was 12 h of light at 0.89 W/m at 50 °C, followed by 12 h of condensation at 60 °C. The devices used were the QUV with Solar Eye irradiance control. 

It was concluded that the technique used was a powerful iheologi-cal technique because it provided quantitative evidence that, as indicated by the xenon and QUV tests, there are significant differences between urethanes (A), (B), and (C) sealants. Also, at least one silieone sealant was much stiffer below -35°C (-31°F) than the polyurethanes studied. One ofthe four multicomponent urethane sealants showed similar performance to silicone sealants under severe test condition. Finally, the authors eoncluded that the current test incorporated in ASTM C 920 Speeifieation for Elastomeric Joint Sealants does not identify the critical performance differences between sealants and must be updated to accomplish this critical task. 

To solve this issue, a new Halar ECTFE with special UV scavenger fillers have been recently developed. To demonstrate the effectiveness of this film to protect UV-sensitive materials, the Halar ECTFE film with UV scavengers was laminated on PET and then placed in a QUV test chamber equipped with UV-B lamp centered at 313 nm. Figure 17.4 shows the effect of UV light on PET, that becomes yellowish, while the Halar film with UV scavengers has been able to effectively protect the PET film underneath and appears almost as transparent and uncolored as the sample before UV test. 

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