U.S. patent application number 17/671700 was filed with the patent office on 2022-06-02 for low voc, high solid deck membranes.
The applicant listed for this patent is CONSTRUCTION RESEARCH & TECHNOLOGY GMBH. Invention is credited to Brian MULLEN, Roland PAVEK, Chia WANG.
Application Number | 20220169886 17/671700 |
Document ID | / |
Family ID | |
Filed Date | 2022-06-02 |
United States Patent
Application |
20220169886 |
Kind Code |
A1 |
WANG; Chia ; et al. |
June 2, 2022 |
LOW VOC, HIGH SOLID DECK MEMBRANES
Abstract
A basecoat coating composition includes an aromatic polyurethane
pre-polymer having isocyanate terminal end groups, a first solvent
and optionally a second VOC-exempt solvent, in which the total
composition formulation has a VOC content of less than 97 g/L. A
topcoat coating composition includes an aliphatic polyurethane
pre-polymer having isocyanate terminal end groups, a first solvent
and optionally a second VOC-exempt solvent, in which the total
composition formulation has a VOC content of less than or equal to
95 g/L. The total composition formulations of the basecoat and/or
topcoat may have a VOC content of less than 50 g/L. A membrane
system may include an optional primer coating, and the above
described basecoat and topcoat coating compositions.
Inventors: |
WANG; Chia; (Shakopee,
MN) ; MULLEN; Brian; (Shakopee, MN) ; PAVEK;
Roland; (Shakopee, MN) |
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Applicant: |
Name |
City |
State |
Country |
Type |
CONSTRUCTION RESEARCH & TECHNOLOGY GMBH |
Trostberg |
|
DE |
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Appl. No.: |
17/671700 |
Filed: |
February 15, 2022 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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16478779 |
Jul 17, 2019 |
11279845 |
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PCT/EP2017/053351 |
Feb 15, 2017 |
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17671700 |
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International
Class: |
C09D 175/04 20060101
C09D175/04; C09D 7/20 20060101 C09D007/20; C08G 18/12 20060101
C08G018/12; C08G 18/62 20060101 C08G018/62; C08G 18/76 20060101
C08G018/76 |
Claims
1. A basecoat coating formulation comprising an aromatic
polyurethane pre-polymer having isocyanate terminal end groups, a
first solvent and optionally a second VOC-exempt solvent, a
catalyst, and at least one filler, in which the total formulation
has a VOC content of less than 97 g/L, the pre-polymer having an
equivalent molecular weight of about 500-10000 g/mol mol and an
NCO/OH ratio of about 1.1 to about 5, and being the reaction
product of about 51 wt % to about 100 wt % aromatic polyisocyanate,
0 wt % to about 49 wt % aliphatic polyisocyanate, and a polyol
selected from the group consisting of polyoxyalkylene polyols,
polyester polyols, and polycarbonate polyols, wherein the weight
percent of polyol to polyisocyanate reacted to form the pre-polymer
is in the range of about 85 to about 95% by weight, based on the
weight of the pre-polymer, wherein the weight percent of the
pre-polymer based on the weight of the total basecoat coating
formulation is about 55.4% to about 95%, and the total weight
percent solids in the base coat formulation is greater than 84% to
about 99%, and, wherein the total formulation viscosity is less
than 80 poise at greater than 84% solids.
2. The formulation of claim 1, wherein the basecoat coating
reaction product has a % NCO in a range of about 1.5% to about
4%.
3. The formulation of claim 1, wherein the basecoat coating
reaction product has a tensile strength of greater than 400
psi.
4. The formulation of claim 1, wherein the basecoat coating
reaction product has a 100% modulus of greater than 175 psi.
5. The formulation of claim 1, wherein the basecoat coating
reaction product has an elongation of greater than 800%.
6. The formulation of claim 1, wherein the basecoat coating
reaction product has a hardness of less than 70 Shore A.
7. The formulation of claim 1, wherein the formulation comprises at
least one of organic fillers, inorganic fillers, a pigment or
colorant, a plasticizer or surfactant, chain extenders,
antioxidants, UV stabilizers, light stabilizers, thermal
stabilizers, fungicides, mildewcides, biocides, fire retardants,
surface additives, coloring agents, mineral oils, dispersing
agents, adhesion promoters, defoaming agents, storage stabilizers,
latent hardeners, cure retarders, drying agents, lubricants,
suspension aids, blocking agents, or mixtures thereof.
8. A membrane system comprising an optional primer coating, a
topcoat, and the basecoat of claim 1.
9. The membrane system defined in claim 8, wherein the membrane
system is a deck membrane.
10. A method of producing a coating membrane having a topcoat and
the basecoat of claim 1, comprising treating a substrate, applying
the basecoat coating formulation to the substrate, and after
drying, applying a moisture curable topcoat coating formulation to
the basecoat, optionally followed by broadcasting aggregate onto
the topcoat.
11. The method of claim 10, wherein said treating is selected from
roughening the substrate chemically or mechanically, or applying a
primer to the substrate.
Description
[0001] The present application is a continuation application of
U.S. Ser. No. 16/478,779, filed Jul. 17, 2019, which is a United
States national stage application of PCT/EP2017/053351, filed Feb.
15, 2017, both of which applications are incorporated herein by
reference in their entireties.
[0002] The present disclosure is directed to polyurethane
compositions for use in coatings and membranes for structures such
as parking decks or garages, plaza decks, balconies, stadiums,
commercial construction, building and restoration. The substrate
may be concrete, plywood or other similar type substrates or
surfaces.
[0003] Annually, parking garage owners spend hundreds of millions
of dollars repairing and protecting the structural slabs in their
parking structures from deicing salts. One integral part of this
process is the installation of traffic bearing membranes to keep
deicing salts from penetrating the structure.
[0004] Manufacturers of deck coatings have come under increasing
pressure to eliminate volatile organic compounds ("VOCs") from
formulations. VOC laws are becoming increasingly more stringent
throughout North America. The VOC content in current polyurethane
deck membrane products are varied from 150 g/L to 200 g/L or
higher. An alternate approach is to use VOC-exempt solvents such as
methyl formate and parachlorobenzotrifluoride (PCBTF) in the
formulation either as a component(s) of a solvent blend or as the
sole solvent in the formulation. Unfortunately, these solvents have
performance features that limit their use in high solids, high
performance polyurethane coatings. Another approach is to
sufficiently reduce the VOC content of the formulation by reducing
or removing the VOC-type solvent. However, it is often the case
that removal or a significant reduction of the VOC-type solvent
negatively effects the viscosity, cost, and surface properties of
the coating.
[0005] What is needed is a high solids, high performance
polyurethane coating or membrane that is formulated to use
VOC-exempt solvents while still meeting strict performance
criteria.
SUMMARY
[0006] Provided is a basecoat coating formulation comprising an
aromatic polyurethane pre-polymer having isocyanate terminal end
groups, a first solvent and optionally a second VOC-exempt solvent,
a catalyst, and at least one filler, in which the total formulation
has a VOC content of less than 97 g/L, [0007] the pre-polymer
having an equivalent molecular weight of about 500-10000 g/mol mol
and an NCO/OH ratio of about 1.1 to about 5, and being the reaction
product of about 51 wt % to about 100 wt % aromatic polyisocyanate,
0 wt % to about 49 wt % aliphatic polyisocyanate, and a polyol
selected from the group consisting of polyalkylene polyols,
polyester polyols, and polycarbonate polyols, wherein the weight
percent of polyol to polyisoisocyanate reacted to form the
pre-polymer is in the range of about 85 to about 95% by weight,
based on the weight of the pre-polymer, [0008] wherein the weight
percent of the pre-polymer based on the weight of the total
basecoat coating formulation is about 55.4% to about 95%, and the
total weight percent solids in the base coat formulation is greater
than 84% to about 99%, and, [0009] wherein the total formulation
viscosity is less than 80 poise at greater than 84% solids.
[0010] Also provided is a topcoat coating formulation comprising an
aliphatic polyurethane pre-polymer having isocyanate terminal end
groups, a first solvent and optionally a second VOC-exempt solvent,
a catalyst, and at least one filler, in which the total formulation
has a VOC content of less than or equal to 95 g/L, [0011] the
prepolymer having an equivalent molecular weight of about 500-10000
g/mol and an NCO/OH ratio of about 1.1 to 3.3, and being the
reaction product of about 51 wt % to about 100 wt % aliphatic
polyisocyanate, 0 wt % to about 49 wt % aromatic polyisocyanate,
and a polyol selected from the group consisting of polyalkylene
polyols, polyester polyols, and polycarbonate polyols, wherein the
weight percent of polyol to polyisocyanate reacted to form the
pre-polymer is in the range of between about 57 to about 87% by
weight, based on the weight of the pre-polymer, [0012] wherein the
weight percent of the pre-polymer based on the weight of the total
topcoat coating formulation is about 57.7% to about 95%, and the
total weight percent solids in the topcoat coating formulation is
greater than 82% to about 99%, and [0013] wherein the total
formulation viscosity is less than 80 poise at greater than 82%
solids.
[0014] Also provided is a membrane system comprising an optional
primer coating, a basecoat and a topcoat, wherein the basecoat is
formed from a basecoat coating formulation comprising an aromatic
polyurethane pre-polymer having isocyanate terminal end groups, a
first solvent and optionally a second VOC-exempt solvent, a
catalyst, and at least one filler, in which the total composition
formulation has a VOC content of less than 97 g/L, the basecoat
pre-polymer having an equivalent molecular weight of about
500-10000 g/mol mol and an NCO/OH ratio of about 1.1 to about 5,
and being the reaction product of about 51 wt % to about 100 wt %
aromatic polyisocyanate, 0 wt % to about 49 wt % aliphatic
polyisocyanate, and a polyol selected from the group consisting of
polyalkylene polyols, polyester polyols, and polycarbonate polyols,
wherein the weight percent of polyol to polyisoisocyanate reacted
to form the basecoat pre-polymer is in the range of about 85 to
about 95% by weight, based on the weight of the basecoat
pre-polymer, [0015] wherein the weight percent of the basecoat
pre-polymer based on the weight of the total basecoat coating
formulation is about 55.4% to about 95%, and the total weight
percent solids in the base coat formulation is greater than 84% to
about 99%, and [0016] wherein the total basecoat formulation
viscosity is less than 80 poise at greater than 84% solids; and
[0017] wherein the topcoat coating formulation comprising an
aliphatic polyurethane pre-polymer having isocyanate terminal end
groups, a first solvent and optionally a second VOC-exempt solvent,
a catalyst, and at least one filler, in which the total topcoat
coating formulation has a VOC content of less than or equal to 95
g/L, [0018] the topcoat prepolymer having an equivalent molecular
weight of about 500-10000 g/mol and an NCO/OH ratio of about 1.1 to
3.3, and being the reaction product of about 51 wt % to about 100
wt % aliphatic polyisocyanate, 0 wt % to about 49 wt % aromatic
polyisocyanate, and a polyol selected from the group consisting of
polyalkylene polyols, polyester polyols, and polycarbonate polyols,
wherein the weight percent of polyol to polyisocyanate reacted to
form the topcoat pre- polymer is in the range of between about 57
to about 87% by weight, based on the weight of the topcoat
pre-polymer, [0019] wherein the weight percent of the topcoat
pre-polymer based on the weight of the total topcoat coating
formulation is about 57.7% to about 95%, and the total weight
percent solids in the topcoat coating formulation is greater than
82% to about 99%, and [0020] wherein the total topcoat formulation
viscosity is less than 80 poise at greater than 82% solids.
[0021] Also provided is a method of producing a coating membrane
having a basecoat and a topcoat, comprising treating a substrate,
applying a moisture curable basecoat coating formulation to the
substrate, and after drying, applying a moisture curable topcoat
coating formulation to the basecoat, the basecoat and topcoat
coating formulations being as defined in claim 16, optionally
followed by broadcasting aggregate onto the topcoat.
BRIEF DESCRIPTION OF THE DRAWINGS
[0022] FIG. 1 is a cutaway perspective view of a polyurethane
membrane comprising an optional primer over the substrate, a
basecoat and a topcoat.
[0023] FIG. 2 is a cutaway perspective view of a polyurethane
membrane comprising an optional primer over the substrate, a
basecoat, a topcoat and an optional second topcoat.
DETAILED DESCRIPTION
[0024] Provided is a low-solvent and low-VOC basecoat and topcoat
coating or membrane system, comprising a combination of high-solids
polyurethane components, optionally one component polyurethanes,
and optionally VOC-exempt solvents. In the polyurethane basecoat
structure, the polymer NCO/OH ratio may be varied, while the final
% NCO may be greater than 1.5% in order to achieve a lower average
molecular weight, such as less than about 2600 g/mol, while the
total formulation viscosity is kept under 80 poise at greater than
84% solids to provide a high solids, flowable coating. In the
polyurethane topcoat structure, the polymer has a lower than
conventional NCO/OH ratio (NCO/OH<3.3) and the average molecular
weight may be increased to greater than 550 g/mol as compared to
conventional topcoat formulations, while the total formulation
viscosity is kept under 80 poise at greater than 82% solids to
provide a high solids, flowable coating.
[0025] Use of the presently claimed basecoat and topcoat is much
safer for the environment, and it is practical and convenient to
use the VOC-exempt solvents compared to conventional lower-solids
formulations with more highly volatile organic compounds. The
products may be manufactured in a conventional commercial
operation, and the products may be applied in the field. The VOC
contents of the subject products are less than 97 g/L for the
basecoat, and less than or equal to 95 g/L for the topcoat, and may
further be as low as about 50 g/L, while still meeting performance
criteria for deck coatings, and the like.
[0026] A solvent mixture comprising a combination of VOC solvents
and VOC-exempt solvents may be utilized to achieve a proper balance
of product formulation properties and cost.
[0027] In general, the subject topcoat coating formulations use a
lower amount of expensive cycloaliphatic isocyanate and a greater
weight percent of polyols than conventional topcoat formulations,
achieving a less costly formulation, while accomplishing good
performance characteristics by modification of the urethane
structure. However, existing raw materials and manufacturing
processes may be utilized to manufacture the coatings, such as deck
membranes, with low VOC characteristics.
[0028] The VOC content in current deck coating products may
generally vary from 150 g/L to 200 g/L, or higher. The subject
embodiments reduce VOC content of the formulations to less than 97
g/L for the basecoat, and less than or equal to 95 g/L for the
topcoat, utilizing high-solids components. The VOC content may be
further reduced to 50 g/L or less including the combination of
high-solids components and VOC-exempt solvents.
[0029] The polyurethane basecoat final product comprises the
reaction product of a reactant formulation comprising (a) a polyol;
(b) an aromatic isocyanate; and optionally (c) at least one
catalyst, (d) a pigment or colorant, and/or (e) a plasticizer and
further optional components. The molar ratio of isocyanate to
polyol (NCO/OH) in the basecoat is between about 1.1 to about 5 in
certain embodiments, and in other embodiments may be between about
1.7 to about 3. The % NCO of the basecoat reaction product may be
in a range between about 1.5% to about 4%, in some embodiments in
the range of 1.6% to about 3%. The polyurethane prepolymer of the
basecoat may optionally comprise some amount of aliphatic and/or
cycloaliphatic isocyanate. The percentage of aliphatic isocyanate
relative to aromatic isocyanate may be between 0 wt % and 49 wt
%.
[0030] The polyurethane topcoat final product comprises the
reaction product of a reactant formulation comprising (a) a polyol;
(b) an aliphatic and/or cycloaliphatic isocyanate; and optionally
(c) at least one catalyst, (d) a pigment or colorant, and/or (e) a
plasticizer and further optional components. The molar ratio of
isocyanate to polyol (NCO/OH) in the topcoat is between about 1.1
to about 3.3 in certain embodiments, and in other embodiments may
be between about 1.5 and about 3.25. The topcoat coating reaction
product may have a % NCO in a range of about 3.5% to about 6%. The
polyurethane prepolymer of the topcoat may optionally comprise some
amount of aromatic isocyanate. The percentage of aromatic
isocyanate relative to aliphatic isocyanate may be between 0 wt %
and 49 wt %. The aliphatic polyisocyanate of the topcoat
pre-polymer may comprise a cycloaliphatic polyisocyanate.
[0031] For illustration purposes but not by way of limitation, the
polyol may be selected from the group consisting of polyalkylene
polyols, polyester polyols, and polycarbonate polyols. The
polyoxyalkylene polyol may be selected from the group consisting of
polyethylene glycols, polypropylene glycols, polypropylene
glycol-polyethylene glycol copolymers, polytetramethylene glycols,
polycaprolactone diols and triols, and combinations thereof. Low
molecular weight diols and triols may also be useful polyols in the
subject formulations. Low molecular weight alcohols such as,
ethylene glycol, 1,3-butanediol, diethylene glycol, dipropylene
glycol, 1,2-propylene glycol, 1,3- propylene glycol, 1,4-butylene
glycol, 2,2-dimethyl-1,3-propane-diol, and mixtures of these
aliphatic polyols may be useful polyol components of the subject
formulations.
[0032] Polyoxyalkylene polyols include polyether polyols prepared
by the copolymerization of cyclic ethers selected from the group
consisting of ethylene oxide, propylene oxide, trimethylene oxide,
tetrahydrofuran, and mixtures of these cyclic ethers, with
aliphatic polyols selected from the group consisting of ethylene
glycol, 1,3-butanediol, diethylene glycol, dipropylene glycol,
1,2-propylene glycol, 1,3-propylene glycol, 1,4-butylene glycol,
2,2-dimethyl-1,3-propane-diol, and mixtures of these aliphatic
polyols. The polyether polyols are functionalized with OH moieties,
and optionally may comprise polyalkylene glycols capped with a
different alylene diol or triol, such as polypropylene glycol
capped with (poly)ethylene diols or triols.
[0033] Representative examples of suitable polyoxyalkylene polyols
include Pluracol CASE polyether polyols commercially available from
BASF Corporation (Wyandotte MI). The polyol may have a nominal
functionality of 2-6, preferably between 2-4, and more preferably 2
or 3.
[0034] In certain embodiments, the polyoxyalkylene polyol of the
polyurethane sealant may have a molecular weight in the range of
about 500 to about 20,000. In other embodiments, the polyol may
have a molecular weight in the range of about 1,000 to about
12,000. In some embodiments, the polyol may have a molecular weight
in the range of about 1,000 to about 6,000. In another embodiment,
the polyol may comprise a polypropylene glycol with a number
average molecular weight in the range of about 1,000 to about
6,000, and the polypropylene glycol may have a degree of
unsaturation of less than about 0.04 meq/g. The molecular weight is
either a calculated molecular weight, i.e. the sum of the atomic
weights of the atoms making up the material, or the molecular
weight is a number average molecular weight determined based on end
group analysis or measurement of colligative properties by
ebulliometry, cryoscopy, or membrane osmometry.
[0035] For purposes of illustration but not by way of limitation,
the isocyanate(s) may have an average functionality equal to about
2.
[0036] For purposes of illustration but not by way of limitation,
the isocyanates may comprise at least one of toluene diisocyanates,
methylene diphenyl diisocyanates, phenylene diisocyanate, xylylene
diisocyanate, diphenylmethane diisocyanate, polyphenylmethane
polyisocyanate (Polymeric MDI), naphthalene diisocyanate,
triphenylmethane triisocyanate, diphenyl sulfone diisocyanate,
cyclohexane diisocyanates, ethylene diisocyanate, propylene
diisocyanate, tetramethylene diisocyanate, hexamethylene
diisocyanates, isophorone diisocyanate, dimers and trimers of these
diisocyanates or mixtures thereof.
[0037] For purposes of illustration but not by way of limitation,
in certain embodiments, the isocyanate may comprise at least one of
toluene 2,4-diisocyanate, toluene 2,6-diisocyanate, naphthylene
1,5-diisocyanate, 4,4'-methylene diphenyl diisocyanate,
2,4'-methylene diphenyl diisocyanate,
1-methyl-2,4-diisocyanatocyclohexane,
1-methyl-2,6-diisocyanatocyclohexane, 4,4'-dicyclohexylmethane
diisocyanate, uretodione diisocyanate, isocyanurate trisocyanate,
hexamethylene-1,6-diisocyanate, tetramethylene-1,4-diisocyanate,
cyclohexane-1,4-diisocyanate, hexahydrotolylene diisocyanate (and
isomers), 1-methoxyphenyl-2,4-diisocyanate,
diphenylmethane-4,4'-diisocyanate, 4,4'-biphenylene diisocyanate,
3,3'-dimethoxy-4,4'-biphenyl diisocyanate,
3,3'-dimethyl-4,4'-biphenyl diisocyanate; and
3,3'-dimethyldiphenylmethane-4,4'-diisocyanate, dimers and trimers
of these isocyanates, or mixtures thereof.
[0038] For purposes of illustration but not by way of limitation,
in some embodiments the isocyanate may comprise at least one of
1-isocyanatomethyl-3-isocyanato-1,5,5-trimethyl diisocyanate
(isophorone diisocyanate, IPDI), toluene diisocyanate (TDI),
methylene diphenyl diisocyanate (MDI), 4,4'-dicyclohexylmethane
diisocyanate, or mixtures thereof.
[0039] For purposes of illustration but not by way of limitation,
in certain embodiments the isocyanate used in the basecoat may be a
toluene diisocyanate (TDI), commercially available as Lupranate.TM.
T80 marketed by BASF Corporation.
[0040] For purposes of illustration but not by way of limitation,
in certain embodiments, the isocyanate used in the topcoat may be a
monomeric cycloaliphatic diisocyanate commercially available as
Desmodur.TM. W (dicyclohexylmethane-4,4'-diisocyanate H.sub.32MDI)
marketed by Bayer Material Science.
[0041] The polyol is typically reacted with a molar excess of
polyisocyanate in a reaction formulation to produce a reaction
product containing an isocyanate-terminated polyurethane
pre-polymer. The amount of polyisocyanate used is sufficient to
provide a ratio of isocyanate equivalence to polyol equivalence
(NCO/OH ratio) in the basecoat of about 1.1 to about 5 in certain
embodiments, and in other embodiments about 1.7 to about 3. The
NCO/OH ratio in the topcoat is between about 1.1 to about 3.3 in
certain embodiments, and in other embodiments between about 1.5 and
about 3.25.
[0042] The weight percent of polyol to polyisocyanate reacted to
form the pre-polymer for the basecoat may be in the range of
between about 85 to about 95% by weight, in certain embodiments
about 86% to about 93% by weight, based on the weight of the
pre-polymer. The weight percent of polyol to polyisocyanate reacted
to form the pre-polymer for the topcoat may be in the range of
between about 57 to about 87% by weight, in certain embodiments
about 63 to about 80% by weight, based on the weight of the
pre-polymer.
[0043] For purposes of illustration but not by way of limitation,
the reactant formulation additionally may comprise additional
solvent, and optionally at least one catalyst, and/or plasticizer.
In certain embodiments, the reactant formulation may additionally
comprise at least one of organic fillers, inorganic fillers, a
pigment or colorant, a plasticizer or surfactant, chain extenders,
antioxidants, UV stabilizers, light stabilizers, thermal
stabilizers, fungicides, mildewcides, biocides, fire retardants,
surface additives, coloring agents, mineral oils, dispersing
agents, adhesion promoters, defoaming agents, storage stabilizers,
latent hardeners, cure retarders, drying agents, lubricants,
suspension aids, blocking agents, or mixtures thereof.
[0044] In one embodiment the total amount of such additives can be
about 10 to about 50 weight percent; and in some embodiments about
25 to about 40 weight percent, based on the total weight of the
reaction product.
TABLE-US-00001 TABLE 1 LIST OF EXEMPT COMPOUNDS (40CFR51.100(s),
revised as of Jul. 1, 2003) Volatile organic compounds (VOC) means
any compound of carbon excluding carbon monoxide, carbon dioxide,
carbonic acid, metallic carbides or carbonates, and ammonium
carbonate, which participates in atmospheric photochemical
reactions. This includes any such organic compounds other than the
following, which have been determined to have negligible
photochemical reactivity: methane ethane methylene chloride
(dichloromethane) 1,1,1-trichloroethane (methyl chloroform)
1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113)
trichlorofluoromethane (CFC-11) dichlorodifluoromethane (CFC-12)
chlorodifluoromethane (HCFC-22) trifluoromethane (HFC-23)
1,2-dichloro 1,1,2,2-tetrafluoroethane (CFC-114)
chloropentafluoroethane (CFC-115) 1,1,1-trifluoro
2,2-dichloroethane (HCFC-123) 1,1,1,2-tetrafluoroethane (HCFC-134a)
1,1-dichloro-1-fluoroethane (HCFC-141b) 1-chloro-1,1-difluoroethane
(HCFC-142b) 2-chloro-1,1,1,2-tetrafluoroethane (HCFC-124)
pentafluoroethane (HFC-125) 1,1,2,2-tetrafluoroethane (HFC-134)
1,1,1-trifluuoroethane (HFC-143a) 1,1-difluoroethane (HFC-152a)
parachlorobenzotrifluoride (PCBTF) cyclic, branched, or linear
completely methylated siloxanes acetone perchloroethylene
(tetrachloroethylene) 3,3-dichloro-1,1,1,2,2-pentafluoropropane
(HCFC-225ca) 1,3-dichloro-1,1,2,2,3-pentafluoropropane (HCFC-225cb)
1,1,1,2,3,4,4,5,5,5-decafluoropentane (HFC-43-10mee)
difluoromethane (HFC-32) ethylfluoride (HFC-161)
1,1,1,3,3,3-hexafluoropropane (HFC-236fa)
1,1,2,2,3-pentafluoropropane (HFC-245ca)
1,1,2,3,3-pentafluoropropane (HFC-245ea)
1,1,1,2,3-pentafluoropropane (HFC-245eb)
1,1,1,3,3-pentafluoropropane (HFC-245fa)
1,1,1,2,3,3-hexafluoropropane (HFC-236ea)
1,1,1,3,3-pentafluorobutane (HFC-365-mfc) chlorofluoromethane
(HCFC-31) 1-chloro-1-fluoroethane (HCFC-151a)
1,2-dichloro-1,1,2-trifluoroethane (HCFC-123a)
1,1,1,2,2,3,3,4,4-nonafluoro-4-methoxy-butane (C4F9OCH3)
2-(difluoromethoxymethyl)-1,1,1, 2,3,3,3-heptafluoropropane
((CF3)2CFCF2OCH3) 1-ethoxy-1,1,2,2,3,3,4,4,4-nonafluorobutane
(C4F9OC2H5)
2-(ethoxydifluoromethyl)-1,1,1,2,3,3,3-heptafluoropropane
((CF3)2CFCF2OC2H5) methyl acetate and perfluorocarbon compounds
which fall into these classes: (i.) Cyclic, branched, or linear,
completely fluorinated alkanes (ii.) Cyclic, branched, or linear,
completely fluorinated ethers with no unsaturations (iii.) Cyclic,
branched, or linear, completely fluorinated tertiary amines with no
unsaturations (iv.) Sulfur containing perfluorocarbons with no
unsaturations and with sulfur bonds only to carbunsaturations (iv.)
Sulfur containing perfluorocarbons with no unsaturations and with
sulfur bonds only to carbon and fluourine
[0045] Under U.S. EPA regulations, a chemical is VOC-exempt, if it:
has vapor pressure of less than 0.1 millimeters of mercury (at 20
degrees Celsius); or, if the vapor pressure is unknown: consists of
more than 12 carbon atoms; or has a melting point higher than 20
degrees C. and does not sublime (i.e., does not change directly
from a solid into a gas without melting).
[0046] For the basecoat and topcoat formulations, a first solvent
may be selected from mineral spirits, xylene, toluene, or Aromatic
100.TM. Aromatic 100 is a Light Aromatic Solvent, (Petroleum)
Naphtha, a mixture composed primarily of C.sub.9-10 dialkyl and
trialkylbenzenes. In certain embodiments, a second solvent may be
used that is a VOC exempt solvent as described above. The second
solvent may be p-chlorobenzotrifluoride (PCBTF), isomers of PCBTF,
methyl formate, and certain chlorinated solvents.
[0047] In certain embodiments the second solvent does not include a
solvent selected from acetone, methyl acetate, methylene chloride,
propylene carbonate, butyl acetate, siloxanes, or water.
[0048] The performance features of the polyurethane polymers of the
basecoat and topcoat compositions are improved with modification of
urethane structures, such as the NCO/OH ratios, final NCO %, amount
of polyols, and selection of the type of polyols, as disclosed and
exemplified herein, to obtain the desired properties for deck
coating applications and the like. Such features include viscosity,
cure time, elongation, strength, modulus, and hardness.
[0049] For the base coat composition, the final NCO% in the
pre-polymer may be about 0.1% to 10%, in certain embodiments about
0.5% to 9%, in some embodiments about 2%-6%, and in other
embodiments about 1.5 to about 4%. The equivalent molecular weight
of the basecoat pre-polymer is typically about 500-10000 g/mol, in
certain embodiments about 700-5000 g/mol, and in some embodiments
about 1500-4000 g/mol. The weight percent total solids in the base
coat formulation embodiments which have a VOC less than 97 g/L is
about 84 to about 99%, in certain embodiments about 84 to about
98%, and in some embodiments about 85 to about 95%. The weight
percent of the polymer based on the total basecoat formulation is
about 55.4 to about 95%, in certain embodiments about 60 to about
90%, and in some embodiments about 65 to 85%.
[0050] The base coat coating pre-polymer reaction product may have,
in various or in combined embodiments, a tensile strength of
greater than 400 psi, a 100% modulus of greater than 175 psi, an
elongation of greater than 800%, and/or a hardness of less than 70
Shore A.
[0051] For the top coat composition, the final NCO % in the
pre-polymer may be about 0.1% to 10%, in certain embodiments about
0.5% to 9%, in some embodiments about 2%-8%%, and in other
embodiments about 3.5 to about 6% . The equivalent molecular weight
of the topcoat pre-polymer is typically about 500-10000 g/mol; in
certain embodiments about 700-5000 g/mol, and in some embodiments
about 800-2000 g/mol. The weight percent total solids in the
topcoat formulation embodiments which have a VOC content less than
or equal to 95 g/L is about 82 to about 99% in certain embodiments
about 83 to about 98%, and in some embodiments about 85 to about
95%. The weight percent of the polymer based on the total topcoat
formulation is about 57.7 to about 95%, in certain embodiments
about 60 to about 90%, and in some embodiments about 65 to about
85%.
[0052] The topcoat coating pre-polymer reaction product may have,
in various or in combined embodiments, a tensile strength of
greater than 2400 psi, a 100% modulus of greater than 700 psi, an
elongation of greater than 525%, and/or a hardness of less than 90
Shore A.
[0053] The following specific examples are provided to illustrate,
but not limit, the preparation of the basecoat and topcoat
polyurethane formulations as discussed above.
EXAMPLES
TABLE-US-00002 [0054] TABLE 2 Basecoat Formulations Items Batch
Comparative A Example 1 Example 2 Example 3 -- COMPONENT WT % WT %
WT % WT % 10 Polyalkylene diol glycol MW4K 14.9 15.3 18.9 18.3 20
Polyalkylene triol glycol MW6K 24.8 25.6 28.6 28.6 30 Polyalkylene
diol glycol MW2K 8.4 8.7 13.7 10.4 40 Polyalkylene diol glycol MW1K
0 0 0 0 50 Suspension aid 0.1 0.1 0.1 0.1 60 Blocking agent 0.3 0.3
0.4 0.3 70 Catalyst 0.1 0.1 0.1 0.1 80 Phosphoric acid 85% <0.1
<0.1 <0.1 <0.1 90 Stabilizer 0.8 0.8 0.9 0.8 100
Pigmenting agent 1.1 1.1 1.1 1.1 110 Inorganic Filler 26.9 28.1
17.7 19.5 140 Hydrophilic fumed silica 0.1 0.1 0.1 0.1 150 Epoxy
functional silane 0.4 0.4 0.4 0.4 160 Latent Hardener(oxazolidine)
0.6 0.6 0.8 0.8 170 Mineral Spirit 15.1 5.8 8.5 3.8 180
p-chlorobenzotrifluoride (PCBTF) 0.0 6.4 0.0 7.5 190 Aromatic
diisocyanate (TDI) 6.4 6.6 8.6 8.2 200 Black pigment <0.1
<0.1 <0.1 <0.1 Total Weight 100 100 100 100
[0055] Procedure for Comparative Example A and Examples 1-3:
[0056] Step A: Items 10 to 50 were added to a mixer and mixed at
low shear for 10 minutes followed by mixing at low and high shear
for an additional 10 minutes.
[0057] Step B: Items 60 to 150 were then added to the mix and mixed
at low shear to wet out, vacuum mixed, heated to 140.degree. F.,
and mixed at low and high shear for 20 minutes.
[0058] Step C: Item 160 was then added to the mix and mixed at low
shear for 10 minutes, vacuum mixed, mixed at low and high shear,
and the percent of water in the mixture was tested.
[0059] Step D: The mixture was cooled to 110.degree. F., items 170
to 190 were then added to the mix and mixed at low shear for 10
minutes followed by mixing at low and high shear until final % NCO
was achieved.
[0060] Step E: Item 200 was then added to the mix and mixed
applying a vacuum.
TABLE-US-00003 TABLE 3 Basecoat Formulations Items Batch Example 4
Example 5 Example 6 Example 7 -- COMPONENT WT WT WT WT 10
Polyalkylene diol glycol MW4K 18.4 18.8 18.3 18.8 20 Polyalkylene
triol glycol MW6K 25.6 24.9 28.6 24.9 30 Polyalkylene diol glycol
MW2K 13.2 10.5 10.9 11.0 40 Polyalkylene diol glycol MW1K 0 5.6 0
5.6 50 Suspension aid 0.1 0.1 0.1 0.1 60 Blocking agent 0.3 0.3 0.3
0.3 70 Catalyst 0.1 0.1 0.1 0.1 80 Phosphoric acid 85% <0.1
<0.1 <0.1 <0.1 90 Stabilizer 0.8 0.8 0.8 0.8 100
Pigmenting agent 1.1 1.1 1.1 1.1 110 Inorganic Filler 19.8 16.2
19.5 16.2 140 Hydrophilic fumed silica 0.1 0.1 0.1 0.1 150 Epoxy
functional silane 0.4 0.4 0.4 0.4 160 Latent Hardener(oxazolidine)
0.7 0.7 0.8 0.7 170 Mineral Spirit 3.8 3.9 3.8 3.9 180
p-chlorobenzotrifluoride (PCBTF) 7.2 7.4 7.4 7.4 190 Aromatic
diisocyanate 8.4 9.0 7.7 8.5 200 Black pigment <0.1 <0.1
<0.1 <0.1 Total Weight 100 100 100 100
[0061] Procedure for Examples 4-7:
[0062] Step A: Items 10 to 50 were added to a mixer and mixed at
low shear for 10 minutes followed by mixing at low and high shear
for an additional 10 minutes.
[0063] Step B: Items 60 to 150 were then added to the mix and mixed
at low shear to wet out, vacuum mixed, heated to 140.degree. F.,
and mixed at low and high shear for 20 minutes.
[0064] Step C: Item 160 was then added to the mix and mixed at low
shear for 10 minutes, vacuum mixed, mixed at low and high shear,
and the percent of water in the mixture was tested.
[0065] Step D: The mixture was cooled to 110.degree. F., items 170
to 190 were then added to the mix and mixed at low shear for 10
minutes followed by mixing at low and high shear until final %NCO
was achieved.
[0066] Step E: Item 200 was then added to the mix and mixed
applying a vacuum.
TABLE-US-00004 TABLE 4 Basecoat Properties Batch Comparative A
Example 1 Example 2 Example 3 VOC, g/Liter 194 96.7 96.4 48.9
Viscosity, poise 46.7 58 43 34.7 Solvent 15.1% Mineral 5.8% Mineral
8.52% Mineral 3.8% Mineral Spirit Spirit 6.4% Spirit Spirit 7.46%
PCBTF PCBTF Solid, Wt. % 83.4 86.3 91.5 88.7 Solid, Vol % 75.4 83
87.7 87.6 Polymer, Wt. % 55.4 57.1 71.1 66.7 Polymer, Vol % 63.3
69.1 78.1 76.5 NCO/OH equiv. ratio 2.050 2.052 2.11 2.22 Final %
NCO 1.57 1.62 2.19 2.16 EW of Polymer 2675 2592 1917 1944 OH
equivalents 0.0357 0.0368 0.0469 0.0426 NCO equivalents 0.0732
0.0755 0.0991 0.0941 Polyols Polyalkylene Polyalkylene Polyalkylene
Polyalkylene diol/triol glycol diol/triol glycol diol/triol glycol
diol/triol glycol Isocyanate Aromatic Aromatic Aromatic Aromatic
Weight/Gallon, LBS 9.8 10.45 9.45 9.92 RT Cure, Days 14 14 14 14
Tensile Strength 361 psi 806 psi 1,090 psi 919 psi 100% Modulus 154
psi 289 psi 270 psi 295 psi Elongation 985% 852% 1043% 918%
Hardness, Shore A 43.6 56.3 56.4 55.8
TABLE-US-00005 TABLE 5 Basecoat Properties Batch Example 4 Example
5 Example 6 Example 7 VOC, g/Liter 48.8 48.9 49.1 49.1 Viscosity,
poise 44.1 44.8 57 66.6 Solvent 3.8% Mineral 3.9% Mineral 3.8%
Mineral 3.9% Mineral Spirit 7.2% Spirit 7.39% Spirit 7.44% Spirit
7.37% PCBTF PCBTF PCBTF PCBTF Solid, Wt. % 88.7 88.7 88.7 88.7
Solid, Vol % 87.6 87.8 87.6 87.8 Polymer, Wt. % 66.8 70 66.7 70
Polymer, Vol % 76.6 78.3 76.5 78.3 NCO/OH equiv. ratio 2.18 1.99
2.03 1.85 Final % NCO 2.2 2.15 1.88 1.88 EW of Polymer 1909 1953
2226 2231 OH equivalents 0.0443 0.0523 0.0435 0.0528 NCO
equivalents 0.0966 0.1033 0.0884 0.0976 Polyols Polyalkylene
Polyalkylene Polyalkylene Polyalkylene diol/triol glycol diol/triol
glycol diol/triol glycol diol/triol glycol Isocyanate Aromatic
Aromatic Aromatic Aromatic Weight/Gallon, LBS 9.93 9.7 9.9 9.68 RT
Cure, Days 26 13 14 21 Tensile Strength 888 psi 919 psi 726 psi 768
psi 100% Modulus 303 psi 241 psi 214 psi 188 psi Elongation 918%
1105% 852% 1081% Hardness, Shore A 57.4 53.7 53 53.2
TABLE-US-00006 TABLE 6 Topcoat Formulations Items Batch Comparative
B Example 8 Example 9 Example 10 Example 11 -- COMPONENT WT WT WT
WT WT 10 Polyalkylene diol glycol MW1K 16 17.6 20.4 20.4 19.1 20
Polyalkylene diol glycol MW4K 8.3 9 10.6 11.5 10 30 Polyalkylene
triol glycol MW6K 13.9 15.3 17.8 17.8 16.7 40 Suspension aid 0.05
0.05 0.05 0.05 0.05 50 Silicone 0.01 <0.02 <0.02 <0.02
<0.02 60 Blocking agent 0.3 0.3 0.3 0.3 0.3 70 Catalyst 0.4 0.4
0.3 0.3 0.3 80 UV stabilizer 2 2 2.1 2 2 110 Pigmenting agent 3.1
3.1 3.2 3.1 3.1 120 Inorganic Filler 17.7 14.7 12.5 13.8 13.2 140
Hydrophilic fumed silica 0.8 0.8 0.2 0.4 0.8 150 Mineral Spirit
18.4 7.4 8.5 8.5 3.7 160 p-chlorobenzotrifluoride 0.0 9.9 0.0 0.0
10.9 (PCBTF) 170 Cycloaliphatic Diisocyanate 18.8 18.9 23.6 21.4
19.3 180 Black Pigment 0.2 0.5 0.5 0.5 0.5 Total Weight 100 100 100
100 100 (rounding)
[0067] Procedure for Comparative Example B and Examples 8-11:
[0068] Step A: Items 10 to 70 were added to a mixer and mixed at
low shear for 10 minutes followed by mixing at low and high shear
for an additional 10 minutes.
[0069] Step B: Items 80 to 140 were then added to the mix and mixed
at low shear to wet out, vacuum mixed, heated to 140.degree. F.,
mixed at low and high shear for 20 minutes, and the percent of
water in the mixture was tested.
[0070] Step C: The mixture was cooled to 110.degree. F., items 150
to 170 were then added to the mix and mixed at low shear for 10
minutes followed by mixing at low and high shear until final %NCO
was achieved.
[0071] Step D: Item 180 was then added to the mix and mixed
applying a vacuum.
TABLE-US-00007 TABLE 7 Topcoat Formulations Items Batch Example 12
Example 13 Example 14 Example 15 Example 16 COMPONENT WT WT WT WT
WT 10 Polyalkylene diol glycol MW1K 17 17.2 19.1 20.5 17.1 20
Polyalkylene diol glycol MW4K 13.3 15.6 13 14 14.2 30 Polyalkylene
triol glycol MW6K 15.7 13.1 13.5 11.3 15.7 40 Suspension aid 0.05
0.05 0.05 0.05 0.05 50 Silicone <0.02 <0.02 <0.02 <0.02
<0.02 60 Blocking agent 0.3 0.3 0.3 0.3 0.3 70 Catalyst 0.3 0.3
0.3 0.3 0.3 80 UV stabilizer 2 2 2 2 2 110 Pigmenting agent 3 3 3 3
3 120 Inorganic Filler 13.2 13.2 13.2 13.2 13.2 140 Hydrophilic
fumed silica 0.8 0.8 0.8 0.7 0.8 150 Mineral Spirit 3.7 3.7 3.7 3.7
3.8 160 p-chlorobenzotrifluoride 11.4 11.6 11.5 12.1 11.5 (PCBTF)
170 Cycloaliphatic Diisocyanate 18.7 18.7 19 18.5 17.7 180 Black
Pigment 0.5 0.5 0.5 0.5 0.5 Total Weight 100 100 100 100 100
(rounding)
[0072] Procedure for Examples 12-16:
[0073] Step A: Items 10 to 70 were added to a mixer and mixed at
low shear for 10 minutes followed by mixing at low and high shear
for an additional 10 minutes.
[0074] Step B: Items 80 to 140 were then added to the mix and mixed
at low shear to wet out, vacuum mixed, heated to 140.degree. F.,
mixed at low and high shear for 20 minutes, and the percent of
water in the mixture was tested.
[0075] Step C: The mixture was cooled to 110.degree. F., items 150
to 170 were then added to the mix and mixed at low shear for 10
minutes followed by mixing at low and high shear until final %NCO
was achieved.
[0076] Step D: Item 180 was then added to the mix and mixed
applying a vacuum.
TABLE-US-00008 TABLE 8 Topcoat Properties Batch Comparative B
Example 8 Example 9 Example 10 Example 11 VOC, g/Liter 205 94.8
94.7 95 49.1 Viscosity, poise 25.3 46 34.4 40.3 43 Solvent 18.4%
Mineral 7.4% Mineral 8.45% Mineral 8.47% Mineral 3.7% Mineral
Spirit Spirit 9.9% Spirit Spirit Spirit 10.9% PCBTF PCBTF Solid,
Wt. % 81.5 82.3 91.5 91.5 85.4 Solid, Vol % 73.81 80.1 88 87.9 84.9
Polymer, Wt. % 57.7 61.5 73.1 71.7 65.8 Polymer, Vol % 62.4 69.1
78.8 78.1 74.5 NCO/OH equiv. 3.292 3.01 3.23 2.9 2.81 ratio Final %
NCO 4.16 4.0 5.19 4.46 3.95 EW of Polymer 1009 1050 808 940 1063 OH
equivalents 0.0432 0.0476 0.0554 0.0557 0.052 NCO equivalents
0.1423 0.1431 0.1791 0.1621 0.1462 Polyols Polyalkylene
Polyalkylene Polyalkylene Polyalkylene Polyalkylene diol/triol
glycol diol/triol glycol diol/triol glycol diol/triol glycol
diol/triol glycol Isocyanate Cycloaliphatic Cycloaliphatic
Cycloaliphatic Cycloaliphatic Cycloaliphatic Weight/Gallon, LBS 9.3
9.73 9.25 9.33 9.74 Tack-free Film Next Day Next Day Next Day Next
Day Next Day RT Cure, Days 14 14 15 14 21 Tensile Strength 2348 psi
3063 psi 3292 psi 3292 psi 3158 psi 100% Modulus 1009 psi 1054 psi
1141 psi 1051 psi 911 psi Elongation 521% 631% 578% 606% 646%
Hardness, Shore A 86.3 83.2 86.4 83.8 84.7
TABLE-US-00009 TABLE 9 Topcoat Properties Batch Example 12 Example
13 Example 14 Example 15 Example 16 VOC, g/Liter 49.2 48.9 49.1 49
49.1 Viscosity, poise 45.2 37.8 33.8 40.4 40.4 Solvent 3.7% Mineral
3.67% Mineral 3.69% Mineral 3.65% Mineral 3.7% Mineral Spirit 11.4%
Spirit 11.6% Spirit 11.47% Spirit 12.08% Spirit 11.5% PCBTF PCBTF
PCBTF PCBTF PCBTF Solid, Wt. % 84.8 84.7 84.8 84.2 84.7 Solid, Vol
% 84.5 84.3 84.4 84 84.4 Polymer, Wt % 65.3 65.1 65.3 64.7 65.1
Polymer, Vol % 73.7 73.6 73.7 73.2 73.7 NCO/OH equiv. 2.89 2.88
2.77 2.6 2.7 ratio Final % NCO 3.88 3.87 3.86 3.6 3.52 EW of
Polymer 1082 1085 1087 1165 1192 OH equivalents 0.0488 0.0491
0.0519 0.0539 0.0494 NCO equivalents 0.1413 0.1413 0.1446 0.1394
0.1333 Polyols Polyalkylene Polyalkylene Polyalkylene Polyalkylene
Polyalkylene diol/triol glycol diol/triol glycol diol/triol glycol
diol/triol glycol diol/triol glycol isocyanate Cycloaliphatic
Cycloaliphatic Cycloaliphatic Cycloaliphatic Cycloaliphatic
Weight/Gallon, LBS 9.75 9.76 9.75 9.76 9.75 Tack-free Firm Next Day
Next Day Next Day Next Day Next Day RT Cure, Days 14 27 14 15 14
Tensile Strength 3062 psi 3148 psi 3158 psi 3150 psi 3089 psi 100%
Modulus 886 psi 913 psi 872 psi 835 psi 787 psi Elongation 702%
766% 668% 758% 742% Hardness, Shore A 84.5 83.5 86.8 82.3 80.9
[0077] Referring to FIGS. 1 and 2, a coating 10, such as a deck
coating or deck membrane is prepared by applying a basecoat
composition described above to a substrate 11, such as concrete, to
form a basecoat 14. The substrate 11 may be precoated with an
optional primer 12, and/or may be pre-treated with a solvent or by
mechanical roughening. Typical primers may include a one-component,
solvent-based primer and sealer such as MasterSeal.TM. P 222, or a
two-component, waterborne, epoxy primer and sealer, such as
MasterSeal.TM. P 220, both available from BASF Corporation. After
drying, a topcoat composition as described above is applied to the
basecoat 14 to form a topcoat 15. An optional second topcoat 16 may
be formed by applying the same or a different topcoating
composition to the dried topcoat 15. The coating compositions may
be roller applied, or applied by other means known in the art, such
as with a brush or sprayed. An aggregate, such as sand, may
optionally be cast onto the surface of the outermost topcoat 15 or
16, optionally prior to full drying, in order to provide a
roughened texture.
[0078] Utilizing the subject coatings, fewer mils thickness of the
"wet" coatings may be applied, and achieving the same "dry" mils
thickness of coatings as those having high VOC components.
Additionally, a lower volume of deck membrane materials having a
low VOC according to the subject embodiments can provide the same
performance as the higher volume of those deck membrane materials
having high VOC. The products are thus more environmentally
friendly than conventional deck membranes.
[0079] It will be understood that the embodiment(s) described
herein is/are merely exemplary, and that one skilled in the art may
make variations and modifications without departing from the spirit
and scope of the invention. All such variations and modifications
are intended to be include within the scope of the invention as
described hereinabove. Further, all embodiments disclosed are not
necessarily in the alternative, as various embodiments of the
invention may be combined.
* * * * *