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Weatherable rigid PVC: The effect of light and thermal stabilizers
Author(s) -
Capocci Gerald
Publication year - 1989
Publication title -
journal of vinyl technology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.295
H-Index - 35
eISSN - 1548-0585
pISSN - 0193-7197
DOI - 10.1002/vnl.730110411
Subject(s) - stabilizer (aeronautics) , tin , thermal stability , carboxylate , titanium dioxide , thermal , materials science , chemical engineering , chemistry , composite material , physics , thermodynamics , organic chemistry , mechanical engineering , engineering , metallurgy
Rigid PVC compositions used in outdoor applications such as siding, profiles, windows, and soffit predominantly contain a tin mercaptide thermal stabilizer. It is well known that tin mercaptides impart outstanding thermal stability to vinyl compounds, however, it is also well known that they provide only marginal light stability. Mercaptides can be used in these applications primarily because they are combined with high levels of titanium dioxide. They are not well suited for dark colored PVC and compositions without titanium dioxide. These require a more weatherable thermal stabilizer, such as a tin carboxylate. In this paper, principles for formulating rigid weatherable vinyl will be discussed. The influence of thermal stabilizers and the interdependence of light stabilizers and thermal stabilizers on PVC photostability will be emphasized. Data will be presented showing how one can formulate weatherable dark brown and pastel PVC through the use of tin carboxylate thermal stabilizers, the appropriate light stabilizers, and pigments. Traditional approaches to achieving weatherability will be compared to what can be attained by capitalizing on the latest advances in stabilization technology. Finally, methods for reducing TiO 2 concentration will be shown.