Formulators
UOP is the world's largest supplier of activated molecular sieve powders
for formulating and compounding applications. Our MOLSIV 3A and 5A
adsorbents, as well as our T (4A based) and L (3A based) activated
powders, have been formulated to provide moisture removal to extremely
low levels with high adsorption capacity. Unlike chemical drying agents,
these adsorbents function by a physical process only, so no reaction
by-products are formed that can adversely affect product properties.
These powders are typically used at levels ranging from 1 to 5 percent by weight,
with specific requirements defined by moisture content analysis of the pigments
and fillers used. Typically, the adsorbent is combined with these components
prior to addition to the formulation.
UOP also offers its L and T adsorbent products as 50% pastes in a castor oil
base, for convenience in formulating solvent-free polyurethane systems. Homogeneous
dispersal of the powder in castor oil allows for quick and convenient addition
into the polyol component. Dispersal of the adsorbent in hydrophobic castor
oil also dramatically reduces the rate of atmospheric moisture pickup during
formulation.
Many coating, sealant, adhesive or elastomeric products are extremely susceptible
to moisture contamination during production and storage. Moisture can be introduced
into these systems from pigments and fillers, as well as from exposure to ambient
moisture during their production.
Moisture will react with isocyanates in polyurethane-based closed cell foams
and in coating, sealant, adhesive or elastomeric products. This may cause product
curing problems, such as CO2 off-gassing, blistering, and degradation of other
physical properties.
In vinyl based foams, pinholes and blemishes on the vinyl surface can occur
when water vaporizes during high-temperature curing. To yield a uniform foam
cell structure, look to UOP VG-100 adsorbent powder for rapid dehydration with
no impact on chemical blowing agents. VG-100 adsorbent is a superior, low alkaline
alternative to quicklime.
In zinc or aluminum-rich paints used for anti-corrosion primers and marine
applications, moisture will react with the metals, generating hydrogen gas
that can overpressure product containers during transport and storage, with
potentially catastrophic results. In addition, if these paints are based on
chlorinated rubber compounds, moisture will also cause hydrolysis, resulting
in gellation and shortened shelf life.
To learn more about how UOP adsorbents can help you optimize your formulation,
contact us directly using our information request form or
by calling one of our worldwide sales offices.
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