Understanding the acceleration factors during durability testing

• Main Author: Leo, Jonathan Wen Rong
• Other Authors: Aravind Dasari
• Format: Final Year Project
• Language: English
• Published: Nanyang Technological University 2021
• Subjects: Engineering::Materials
• Online Access: https://hdl.handle.net/10356/147907
• Institution: Nanyang Technological University

Accelerated weathering tests that are able to simulate ultra-violet (UV) irradiation, temperature and moisture from the natural environment have long been used to test the durability of materials. However, in an accelerated weathering test, the material is tested on its durability in a simulated and controlled environment which could lead to failure when exposed to the varying factors involved in the end use environment. Therefore, a correlation between natural weathering and accelerated weathering is needed. Despite numerous studies done on establishing a correlation, an understanding of the different factors involved in weathering is not as well researched on. In an attempt to understand the factors involved in weathering, an acrylic based intumescent coating is being exposed to natural weathering tests and accelerated weathering tests before conducting an ATR-FTIR to identify the chemical bonds and analyse changes that occurred, a thermogravimetric analysis to observe changes to thermal stability and residual weight percentage as well as a furnace tests simulating the ISO 834 fire curve to determine its fire protection performance. It is well known that UV irradiation causes chemical changes such as chain scissoring and depolymerisation to the polymer resin, with the thermogravimetric analysis revealing the possibility of UV irradiation improving the curing of the acrylic based resin and raising its thermal stability. Results conclude that UV irradiation is most likely the primary factor in the degradation of the acrylic based intumescent coating and that the accelerated weathering tests can be correlated to the natural weathering tests to a certain degree. The addition of TiO2 as a UV absorbers has also shown its positive effect of mitigating the effects caused by UV irradiation.