NOTICE: Due to a lapse in annual appropriations, most of this website is not being updated. Learn more.

Form submissions will still be accepted but will not receive responses at this time. Sections of this site for programs using non-appropriated funds (such as NVLAP) or those that are excepted from the shutdown (such as CHIPS and NVD) will continue to be updated.

U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

PUBLICATIONS

Effect of Heterogeneity in Nano-TiO2 Filled Acrylic Urethane Coatings on Surface Degradation under Accelerated UV Exposure

Published

Author(s)

Yongyan Pang, Stephanie S. Watson, Li Piin Sung

Abstract

The objective of this study was to investigate how the heterogeneity due to nanoparticle dispersion of polymeric coatings affects surface morphological changes during ultraviolet (UV) exposure under different weathering conditions. Three types of nano-titanium dioxide (nano-TiO2) were chosen to mix into a solvent-borne acrylic urethane (AU) coating to generate different nanoparticle dispersion states. Two accelerated weathering conditions: wet (30 °C and 75 % relative humidity (RH)) and dry (30 °C and 0 % RH), were selected to investigate the effect of humidity on morphological changes in polymeric coatings. Attenuated Total Reflectance-Fourier Transform Infrared spectroscopy (ATR FTIR) was used to monitor surface chemical degradation. Laser scanning confocal microscopy (LSCM) was used to characterize nanoparticle dispersion and monitor the surface morphological changes in the AU coatings during the UV exposure. Surface degradation patterns were different in these three coatings, and severe degradation was observed near large nanoparticle clusters. The degradation rate was estimated using chemical and physical changes as a function of UV exposure time. The surface degradation patterns were similar among the coatings containing the same type of nanoparticles in the wet and dry conditions, but the degradation rate was faster in wet conditions. Physical changes in surface roughness values present a better correlation to the surface degradation than chemical changes.
Citation
Polymer Degradation and Stability
Pub Type
Journals

Keywords

Accelerated weathering, infrared spectroscopy, laser scanning confocal microscopy, nanocomposites, nanoparticle dispersion, photoreactivity, surface morphology, UV degradation
Polymers, Nanomaterials, Materials, Building materials and Biomaterials

Citation

Pang, Y. , Watson, S. and Sung, L. (2014), Effect of Heterogeneity in Nano-TiO2 Filled Acrylic Urethane Coatings on Surface Degradation under Accelerated UV Exposure, Polymer Degradation and Stability (Accessed October 10, 2025)

Issues

If you have any questions about this publication or are having problems accessing it, please contact [email protected].

Created October 29, 2014, Updated October 12, 2021
Was this page helpful?