Description:
CD420 and SR833S are monomers that demonstrate excellent yellowing
resistance and gloss retention during laboratory accelerated
weathering tests. These studies have been performed without
the aid of hindered amine light stabilizers (HALS) or UV light
absorbers. CD420 and SR833S exhibit excellent weathering performance
compared to CN9001, an aliphatic urethane oligomer with proven
exterior durability. The viscosities of these monomers are quite
low, and they can be used as reactive diluents for high molecular
weight oligomers without adversely impacting weathering performance.
SR833S, owing to its excellent cured film properties, can also
be used as a standalone product.
Product features and
typical physical properties are shown in Tables 1 and 2.
Blends of CD420 and
SR833S were compared with neat CN9001 for weathering performance
and gloss resistance based on the formulations and application
conditions shown in Tables 3 and 4.
Figure 1 shows the
results of accelerated weathering tests using a xenon testing
chamber. CN9001, an aliphatic urethane oligomer with excellent
weathering properties, provides a baseline for the evaluation
of the CD420 and SR833S blends. Yellowness indices for all three
products drop to very low levels and maintain these impressive
levels without the use of HALS or UV absorbers. These results
indicate that weathering resistance is similar for the neat
monomers and CN9001.
Figure 2 illustrates
that a constant level of gloss is maintained over the duration
of the accelerated weathering tests. CD420 and SR833S again
demonstrate performance comparable to CN9001.
