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Increasingly
stringent environmental regulations mandate lower and lower
VOC levels in coatings. Traditionally, cosolvents are added
to waterborne coatings to assist film formation and improve
performance properties. Approximately half the total latexes
produced are utilized in paper, paperboard, and architectural
coatings. VOMM-based latexes have been formulated into coatings
that do not require cosolvents to achieve efficient film formation.
Paper coatings formulated with VOMM-based latexes perform competitively
in lab evaluations against commercially available latexes. Research
efforts are underway to improve performance and increase VOMM
content in latexes for commercial paper coatings.
Coatings
for exterior applications such as Navy Haze Gray are applied
to the topside of ships and form an integral component of the
ship's permanent counter-measures. Apart from protecting topside
mechanical equipment and structures from the weather, the coatings
also provide visual camouflage by blending the ship into the
open ocean background. Current Navy Haze Gray coatings are formulated
from solvent-based silicone modified alkyds that contain substantial
levels of VOCs. In contrast, TRRG is investigating a linseed
oil-based latex. These extremely environmentally responsible,
waterborne coatings release minimal odor and possess less than
1g/L VOCs. The experimental latex polymers produce coatings
that meet military specifications and offer the advantages of
easy cleanup, reduced fire hazards, and low toxicity to Navy
personnel.
VOMM-based
latexes have been formulated into waterborne nail polishes.
Commercial nail polishes typically contain more than 60 weight
percent solvents and are highly odoriferous. Increasing concerns
over sensitivities to certain nail polish ingredients was the
impetus for this work. For instance, toluene sulfonamide resin
is a source of formaldehyde and is considered to be the main
ingredient responsible for allergic reactions to nail polishes.
The presence of phthalates is also a concern due to health risks,
for example, birth defects. The solvents used in nail polishes
can cause headaches in some people. TRRG has completed screening
studies with a VOMM-based waterborne polymer nail polish possessing
minimal odor and low-to-zero VOCs while maintaining the desired
gloss, flow and leveling, and drying properties. Currently,
our focus is to achieve early high hardness values.
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