Effect of Microstructure of Fluorinated Acrylic Coatings on UV Degradation Testing.
Effect of Microstructure of Fluorinated Acrylic Coatings
on UV Degradation Testing.
(400 K)
Sung, L. P.; Vicini, S.; Ho, D. L.; Hedhli, L.;
Olmstead, C.; Wood, K. A.
Polymer, Vol. 45, No. 19, 6639-6646, 2004.
Keywords:
coatings; acrylics; degradation; fluorocarbons; material
properties; exposure
Abstract:
This paper presents research results on the
relationships between the microstructure and the
performance/weatherability of fluoropolymer/acrylic
coatings. We studied fluoropolymer/acrylic blends of
identical composition, prepared as films using three
different methods: 2-stage emulsion polymerization
followed by latex film formation; cold-blending
(physically mixing) acrylic and fluoropolymer latex
dispersions followed by latex film formation; and
solution casting using an organic solvent. We
investigated the effects of the mixing method, and the
level of acrylic in the blend on the
microstructure/morphology and on the durability-related
physical properties of the fluoropolymer/acrylic films.
Small angle neutron scattering was performed to
determine the microstructure/morphology of
fluoropolymer-rich micro-domains in the coatings
prepared using these three methods. The physical
properties tested included the glass transition
temperature, the crystallinity fraction, and the tensile
strength. The mass loss rates observed during UV
exposure testing correlate with the final
microstructures of the films.