文献名： Influence of surface modified nano silica on alkyd binder before and after accelerated weathering

作者： Miroslav Nikolica, Hiep Dinh Nguyenb, Anders Egede Daugaardb, David Löfc, Kell Mortensend, Søren Barsberga, Anand Ramesh Sanadia
a Department of Geosciences and Natural Resource Management, IGN, University of Copenhagen, Rolighedsvej 23, DK-1958 Frederiksberg C, Denmark
b Department of Chemical and Biochemical Engineering, Technical University of Denmark, Søltofts Plads, Bygning 227, DK-2800 Kgs., Lyngby, Denmark
c PPG Architectural Coatings EMEA, Dyrup A/S, Gladsaxevej 300, DK-2800 Søborg, Denmark
d Niels Bohr Institute, X-ray and Neutron Science, University of Copenhagen, Universitetsparken 5, DK-2100 København Ø, Denmark

摘要：Introduction of nano fillers in exterior wood coatings is not straight forward. Influence on aging of polymer binder needs to be taken into account along with possible benefits that nano fillers can provide immediay after application. This study shows the influence of two differently modified hydrophobic nano silica on an alkyd binder for exterior wood coatings. One month after application, the highest strength and energy required to break the films was obtained with addition of 3% disilazane modified silica. Changes in tensile properties were accompanied with a small increase in glass transition temperature. However, the highest stability upon accelerated weathering, measured by ATR-IR and DMA, was for nano composites with the highest amount of nano filler. The reasons for the observed changes are discussed together with the appearance of a feature that is possibly a secondary relaxation of alkyd polymer.

关键词：Alkyd; Exterior wood coatings; Nanocomposites; Surface modification; Nano silica; Accelerated weathering