The influence of ultraviolet radiation on the optical properties of glass fibre reinforcements for polyurethane matrix composites

Abstract

Polyurethanes represent one of the most frequently used polymeric matrixes in composites. Although there have been many studies focused on the weather resistance of polyurethanes, this important property is unheeded during the reinforcing phase. In this article, the effects of ultraviolet (UV) radiation on the changes in optical properties of commercially available glass fibre reinforcements containing various polymeric binders used as compatibilising agents for the polymeric matrix in the final composite products were studied. The standardised experiments were performed using accelerated ageing equipment, q‐lab ultraviolet tester, in dry mode. Chemical modification of the binder in the form of polyesters or silanes by UV irradiation was studied using Fourier Transform–infrared spectroscopy. Changes in the optical properties caused by the degradation processes of polymeric components due to UV irradiation were evaluated based on colour changes in the examined samples using the yellowness index; statistical evaluation of the data obtained was conducted with an Anderson–Darling test of normality and an ANOVA test. It was demonstrated that both the amount of the binder and the glass fibre reinforcement's construction play a more important role than the chemical structure of the binder.

Optically Active Polyurethane/Silica Aerogel Coated Cotton Fabrics for Thermal Protection

“…OPU has a better thermal stability than polyurethane due to its evident blocking and refracting effects to Infrared and visible lights (Sedlacik et al, 2019)., as a result OPU/SiO 2 aerogel composites are supposed to exhibit better thermal stability than widely used PU/SiO 2 aerogel. Figure 3C shows the TG curves of both OPU/SiO 2 aerogel (1:15 ratio) and PU/SiO 2 aerogel.…”

“…As an example, optically active polyurethane (OPU) has been synthesized to enhance the thermal stability especially the thermal radiative protection of polyurethane. OPU has evident blocking and refracting effects to Infrared and visible lights, resulting in thermal radiative protection performance to the coated materials (Sedlacik et al, 2019). OPU has the potential to be an ideal adhesive film on textiles to serve different purposes.…”

Polymer Processing and Surfaces

“…While developing the next generation of polymeric and composite materials, the material’s resources, the utility properties of the product, its economy aspects, as well as environmental issues can be optimized. The surface of the filler or final product is of particular interest with respect to the interaction with its surroundings; hence, its modification can positively affect the stimuli-responsive character, adhesion, absorption, tribological properties or biomedical application, among others [ 1 , 2 , 3 , 4 , 5 ].…”