WEATHERING | TESTING
Taking on the weather
Accelerated weathering testing can provide vital data in the development of plastics for outdoor applications, but the need for validation remains. Mark Holmes reports
The outdoor performance of plastics has improved significantly over many decades through develop- ments in stabiliser and pigment technologies in ever more stable and durable compounds. Understanding the performance boundaries of these compounds is essential to matching the materials to the outdoor application. Accelerated weathering testing is now a well-established technique in determining these parameters, although the need to correlate these findings to real-time outdoor exposure remains vital. Accelerated weathering testing for plastic compounds has been vital for the industry for many years and the fundamental and most basic require- ment is to provide the most reliable results in the quickest amount of time. “These have been the main market requirements for some time,” says Matt McGreer, Senior Product Manager/Global Stand- ards Manager, Atlas Material Testing Technology. “Beyond that, the next level of requirement involves a more complete understanding of what is really happening at the sample level in terms of the radiation received, surface temperature and moisture application, for example, beyond just the basic test method parameters and set points.” However, improvements in accelerated testing techniques are also closely aligned to the develop- ment of standards. “Users of accelerated testing instruments are always driven by the requirements in test methods and industry standards,” says McGreer.
www.compoundingworld.com
“If those requirements do not include new develop- ments or improvements, then the market success of that new feature can be limited. As standards development can be very competitive, if not all weathering instrument manufacturers provide instruments that have that new feature, it is difficult to get agreement for its inclusion because it puts that company at a distinct competitive disadvantage.” McGreer says it is important that during the
standards development process, enough technical data justifying the benefit of a new technology to the plastics industry be made available. A sufficiently strong technical argument can compel the adoption of state-of-the-art features that will ultimately enable more sophisticated materials’ development. One essential requirement in achieving true service life prediction is an understanding of what is really going on at the sample level. “Existing instruments in the field that may be perfectly capable of running that basic test method may not be equipped with a new development that gives the user this critical knowledge,” he says. “There have been many recent papers and presentations at industry and standards symposia that have high- lighted the need for this information, as well as ways in which this data can be collected. Atlas has two relatively new developments that assist in providing more information about what is really happening to a sample during exposure. These include the Specific Specimen Surface Temperature (S3
T) December 2019 | COMPOUNDING WORLD 45
Main image: Simulating the effect of
sunlight and outdoor exposure is a big challenge for compound developers but accelerated methods and understanding is improving
IMAGE: SHUTTERSTOCK
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60 |
Page 61 |
Page 62 |
Page 63 |
Page 64 |
Page 65 |
Page 66 |
Page 67 |
Page 68 |
Page 69 |
Page 70 |
Page 71 |
Page 72 |
Page 73 |
Page 74 |
Page 75 |
Page 76
