MELCROSS-03
has advantages
as economical, fast catalyzed
cure, solvent-free, excellent
stability,
Wide compatibility
and solubility with various
kinds of resins, excellent hardness-film
flexibility.
Introduction
MELCROSS-03
crosslinking agent is a commercial
grade of Hexamethoxymethylmelamine(HMMM)
which supplied in liquid form. It is
a versatile crosslinking agent
for a wide range of polymeric
materials, both organo-soluble
and water-borne. MELCROSS-03
is soluble in most commonly
used organic solvent but solubility
in water is limited-when blended
with most other water-reduciable
resins, tolerates dilution in
water. The polymeric
materials should contain either
hydroxyl or amide groups.
The reaction of MELCROSS-03
with hydroxyl, carboxyl and
amide functionalities on other
polymers is typically catalyzed
with strong acid because of
its high extent of alkylation. The polymeric
materials would include alkyds,
polyesters, acrylic, epoxy,
urethane, and cellulosics.
MELCROSS-03 is a very
effective crosslinking agent
because of its high functionality
and low tendency to self condensation. In particular,
it can provide films with high
flexibility
when used with polyesters.
Typical
properties
Appearance |
|
Clear,
viscous liquid |
Non-volatile |
Wt.% |
98.0
min. |
Color,
Gardner
1963 |
|
1
max. |
Viscosity,
Cone/Plate |
cps |
1400
- 5000 |
Specific
gravity |
25¡ÆC |
1.2 |
Refractive
index |
|
1.515
? 1.520 |
Flash
point |
¡ÆF |
>200 |
Free
formaldehyde |
Wt% |
0.25max. |
Application
High solid
or water-borne finishes,
Automotive
or general metals finishes,
Coil or
container, PCM coatings, Inks.
¡Ø Suggested
formulation
of
Flexible white
metal decorating enamel
Rutile
titanium dioxide
|
32.00 |
Tiona
RH472, Laporte
Industries Ltd. |
Oil
free polyester |
33.50 |
NV=60,
AV=10, VIS=8000cts,
G#COLOR=6 |
MELCROSS-03 |
4.90 |
P&ID
Co.,Ltd. |
Solvesso
150 |
14.12 |
Esso
Chemicals Ltd. |
Cellosolve
acetate |
14.12
|
Union
Carbide Ltd. |
Butyl
cellosolve |
0.60 |
Union
Carbide Ltd. |
Modaflow,
flow agent |
0.21 |
Monsanto
Ltd. |
20%
PTSA |
0.55 |
|
Total |
100.00 |
|
Viscosity
at 25¡ÆC, 2500sec-1
150cps Pigment
: binder ratio
1.3 : 1 Vehicle
solids
37% Paint
solids
57%
Stoving
schedule : 10 to15
minutes at 150¡ÆC or to
peak metal temp. of 240¡ÆC.
Special
Properties of HMMM.
There
is one member of the melamine-formaldehyde
coating resin
family that deserves special
consideration.
This is hexamethoxymethylmelamine(HMMM).
This is
a methylated rather than a butylated
or isobutylated product.
HMMM, as opposed to
melamine-formaldehyde resins
of the usual type, does not
self-condense to any great degree.
The reaction is primarily
with the sites on the backbone
of the principal film former,
the alkyd resin. This means
that embrittlement with aging,
such as imparted when the conventional
melamine resin self-condenses,
is not present.
It means
also that the distribution of
molecular structure is more
linear,
imparting better flexibility.
If one-half
the amount of a butylated melamine-formaldehyde
resin is replaced by HMMM in
a given formulation, and the
difference made up with alkyd
resin, the formulation will
have equal hardness, better
gloss, better chemical resistance,
and better stability. Because
of the inherent stability of
the HMMM molecule, acid catalyst
are necessary to initiate a
reaction with the hydroxyl groups
on the alkyd resin; however,
such catalyzed mixtures are
package stable, contrary to
experience with other melamine
?formaldehyde coating types.
HMMM will
react with thermosettable acrylic
polymers, either through hydroxyl
or carboxyl groups, with the
same improvement in properties
as described for alkyd types.
HMMM is
compatible with epoxy resins
and may be used in the same
manner as urea-formaldehyde
resins are used to cross-link
these polymers.
Less is required,
and improvements in initial
color, gloss, and chemical resistance
may be expected.
SAFETY
General
Attention
must be paid to the normal precautions
for handling chemicals and to
the measures prescript in the
local health regulations.
The work place must
be well ventilated, skin care
measures should be adapted and
safety goggle should be worn.
Safety
data sheet
P&ID Co.,LTD shall
provide MSDS
associated with MELCROSS-03
as your request. MSDS of
MELCROSS-03
Storage
If MELCROSS-03 is
kept in tightly closed drums
or in storage tanks in the cool
place, its shelf life is 12
months.
Remark
This
information is given without
any warranty or representation.
We do not assume any legal responsibility
for same, nor do we give permission,
inducement, or recommendation
to practice any patented invention
without a license.
It is offered solely
for our consideration, investigation
and verification.
Before using any product,
read its label.
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