The Effects of UV Light on the Chemical and Mechanical Properties of a Transparent Epoxy-Diamine System in the Presence of an Organic UV Absorber

• Published in: Materials Vol. 10; no. 2; p. 180
• Main Authors: Nikafshar, Saeid, Zabihi, Omid, Ahmadi, Mojtaba, Mirmohseni, Abdolreza, Taseidifar, Mojtaba, Naebe, Minoo
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 14-02-2017; MDPI
• Subjects: Absorbers; Diamines; Epoxy resins; Fourier transforms; Glass transition temperature; Infrared analysis; Infrared spectroscopy; Low temperature; Low temperature resistance; Mechanical properties; Mechanical tests; Morphology; Physical properties; Tensile strength; Ultraviolet radiation; Volatile compounds; epoxy resin; Tinuvin 1130; photodegradation process; UV absorber
• ISSN: 1996-1944; 1996-1944
• DOI: 10.3390/ma10020180

Despite several excellent properties including low shrinkage, good chemical resistance, curable at low temperatures and the absence of byproducts or volatiles, epoxy resins are susceptible to ultra violet (UV) damage and their durability is reduced substantially when exposed to outdoor environments. To overcome this drawback, UV absorbers have been usually used to decrease the rate of UV degradation. In this present study, the effects of UV light on the chemical, mechanical and physical properties of cured epoxy structure, as well as the effect of an organic UV absorber, Tinuvin 1130, on the epoxy properties were investigated. Chemical changes in a cured epoxy system as a result of the presence and absence of Tinuvin 1130 were determined using Fourier transform infrared spectroscopy (FT-IR) analyses. The effect of Tinuvin 1130 on the surface morphology of the epoxy systems was also investigated by scanning electron microscopy (SEM) imaging. Additionally, the glass transition temperatures (
) before and during UV radiation were measured. After an 800 h UV radiation, mechanical test results revealed that the lack of the UV absorber can lead to a ~30% reduction in tensile strength. However, in the presence of Tinuvin 1130, the tensile strength was reduced only by ~11%. It was hypothesized that the use of Tinuvin 1130, as an organic UV absorber in the epoxy-amine system, could decrease the undesirable effects, arising from exposure to UV light.