U.S. patent application number 09/953426 was filed with the patent office on 2002-03-14 for method and composition for waterproofing.
This patent application is currently assigned to Protective Coatings Technology, Inc.. Invention is credited to Gaveske, John H..
Application Number | 20020032263 09/953426 |
Document ID | / |
Family ID | 23176175 |
Filed Date | 2002-03-14 |
United States Patent
Application |
20020032263 |
Kind Code |
A1 |
Gaveske, John H. |
March 14, 2002 |
Method and composition for waterproofing
Abstract
A method and composition for waterproofing a substrate herein is
described which includes applying a coating composition to a
surface of the structural unit. The coating composition includes a)
an organic solvent, b) a hydrocarbon resin and c) a styrene
polymer, having a styrene content of about 60 wt % or greater,
selected from the group consisting of a copolymer having styrene
and diene monomer units, a copolymer having styrene and olefin
monomer units, a polymer having styrene monomer units and mixtures
thereof.
Inventors: |
Gaveske, John H.; (Blaine,
MN) |
Correspondence
Address: |
MERCHANT & GOULD PC
P.O. BOX 2903
MINNEAPOLIS
MN
55402-0903
US
|
Assignee: |
Protective Coatings Technology,
Inc.
Minneapolis
MN
|
Family ID: |
23176175 |
Appl. No.: |
09/953426 |
Filed: |
September 14, 2001 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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09953426 |
Sep 14, 2001 |
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09628709 |
Jul 31, 2000 |
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09628709 |
Jul 31, 2000 |
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09304354 |
May 4, 1999 |
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Current U.S.
Class: |
524/425 ;
524/445; 524/492; 525/210 |
Current CPC
Class: |
C04B 41/4865 20130101;
C04B 41/463 20130101; C04B 41/4876 20130101; C04B 41/4876 20130101;
C04B 2111/27 20130101 |
Class at
Publication: |
524/425 ;
524/445; 524/492; 525/210 |
International
Class: |
C08K 003/26; C08K
003/34; C08L 045/00 |
Claims
I claim:
1. A waterproofing composition, comprising: about 33 phr to about
250 phr of an organic solvent; about 10 phr to about 50 phr of a
polyindene; and about 50 phr to about 90 phr of a styrene polymer,
having a styrene content of about 60 wt % or greater, selected from
the group consisting of a copolymer having styrene and diene
monomer units, a styrene homopolymer and mixtures thereof.
2. The waterproofing composition of claim 1, wherein the diene
monomer units include butadiene, isoprene and mixtures thereof.
3. The waterproofing composition of claim 1, wherein the styrene
polymer has a styrene content of 85 wt. % or greater.
4. A waterproofing composition, comprising: about 50 to about 150
phr of an organic solvent; about 30 phr to about 50 phr of a
polyindene; about 50 phr to about 70 phr of a styrene polymer,
having a styrene content of about 60 wt % or greater, selected from
the group consisting of a copolymer having styrene and diene
monomer units, a styrene homopolymer and mixtures thereof.
5. The waterproofing composition of claim 4, wherein the diene
monomer units include butadiene, isoprene and mixtures thereof.
6. The waterproofing composition of claim 4, wherein the styrene
polymer has a styrene content of 85 wt. % or greater.
7. The waterproofing composition of claim 4, further comprising
about 20 phr to about 600 phr of a filler
Description
RELATED APPLICATIONS
[0001] This is a continuation of U.S. Ser. No. 09/628,709, filed
Oct. 3, 2001, which is a divisional of U.S. Ser. No. 09/304,354,
filed May 4, 1999, which applications are expressly incorporated
herein.
FIELD OF THE INVENTION
[0002] The present invention relates to a method and a polymeric
composition for waterproofing. More particularly, the present
invention relates to a method and composition using an organic
solvent, a hydrocarbon resin and a polymer having at least one
styrene-containing polymer to form a waterproof film.
BACKGROUND OF THE INVENTION
[0003] Structures used in construction, such as foundations and
walls, include materials, such as masonry, cement, wood, plaster,
stone, clay or brick that may be porous. Such porous materials are
susceptible to cracking and can be degraded by water and/or loss of
water from the porous materials. Below grade structures are often
subjected to hydrostatic pressure from ground water. Above grade
structures are subject to precipitation and water from other
sources. A variety of methods and products for waterproofing and/or
sealing these structures against outside water have been
developed.
[0004] One type of waterproofing and/or sealing system includes
polyvinyl or polyethylene sheeting adhered or fastened to the
surface of the structure. If an adhesive is used to adhere the
sheeting to the structure, the adhesive may not stick well due to
dust (e.g., cement or stone dust) produced during construction and
other activities and lose its adhesion over time. On the other
hand, if fasteners, such as nails or staples, are used to attach
the sheeting to the structure, the fasteners typically puncture the
sheeting and the structure beneath, providing a channel through
which water can flow. Moreover, there are seams between the sheets
that require the use of a fastener or adhesive to close. The
adhesive may be attacked by microorganisms and/or oxidation and
degraded or may dissolve in water over time, allowing water to flow
through the seam. Fasteners puncture the sheeting and allow water
through the resulting holes. In addition, the waterproofing sheets
are often difficult to form around non-uniform structures and
adverse weather conditions may hinder the placement of the sheets
on the structure. For example, wind may cause wrinkles in the sheet
as it is positioned on the structure and, on very cold days, the
sheets may tear or even shatter during installation.
[0005] Another type of waterproofing and/or sealing system includes
the application of a coating composition on the structure. One
common type of coating composition for waterproofing and sealing is
tar- or asphalt-based. Although these compositions are relatively
inexpensive and can be applied year-round, the materials in the
composition often leach away from the wall. This often contaminates
the soil and reduces the amount of protection afforded by the
coating. Moreover, these compositions typically contain a large
amount of organic material which may be attacked by soil- or
water-borne microorganisms, thereby reducing the effectiveness of
the coating.
[0006] Other types of coating compositions have been developed.
Many of these coating compositions, however, do not produce a
durable film over porous substrates (e.g., cement, masonry blocks,
wood, etc.). Often, the film that is formed using these coating
compositions is easily punctured and/or includes components that
are degradable or leach away from the film thus losing its adhesion
to substrates. These coating compositions need to be applied with a
significant amount of volatile organic compounds as solvents. These
emitted volatile organic compounds (VOCs) are limited by current
environmental regulations. Moreover, a number of the coating
compositions are difficult to apply and/or relatively
expensive.
[0007] There is a need for alternative waterproofing and/or sealing
compositions which emit less volatile organic compounds upon
application, are durable, possess a long life span, and stable in
below grade and above grade applications. In addition, new
compositions and sealing structures are needed which are useful
year round, even in northern latitudes. Such compositions may also
be useful for coating other substrates, as well.
SUMMARY OF THE INVENTION
[0008] The present invention relates to methods and compositions
for waterproofing and sealing a surface of a substrate. One
embodiment is a method of waterproofing a surface of a substrate.
The method includes applying a coating composition to the surface
of the substrate. The coating composition includes a) an organic
solvent, b) a hydrocarbon resin and c) a styrene polymer, having a
styrene content of about 60 wt % or greater, selected from the
group consisting of a copolymer having styrene and diene monomer
units, a copolymer having styrene and olefin monomer units, a
polymer having styrene monomer units and mixtures thereof.
[0009] A further embodiment is a method of waterproofing a surface
of a substrate. This method includes applying a coating composition
to the surface of the substrate. The coating composition includes:
a) an organic solvent, b) about 1 to about 85 phr of a
coumarone-indene polymer; and c) about 15 to about 99 phr of a
styrene polymer, having a styrene content of about 60 wt % or
greater, selected from the group consisting of a copolymer having
styrene and diene monomer units, a styrene homopolymer and mixtures
thereof.
[0010] Another embodiment is a method of applying a waterproofing
coating to a structural unit. A coating composition is applied to a
surface of the structural unit. The coating composition includes;
a) about 20 to 400 phr of an organic solvent, b) about 1 to 65 phr
of a coumarone-indene polymer, c) about 35 to 99 phr of a styrene
polymer, having a styrene content of about 60 wt % or greater,
selected from the group consisting of a copolymer having styrene
and diene monomer units, a styrene homopolymer and mixtures
thereof, and d) about 20 to 600 phr of a filler. The coating
composition is then dried to form a film.
[0011] A further embodiment of the invention is a waterproofing
composition. The waterproofing composition includes; a) about 33
phr to about 250 phr of an organic solvent, b) about 10 to 50 phr
of a coumarone-indene polymer; c) about 50 to 90 phr of a styrene
polymer, having a styrene content of about 60 wt % or greater,
selected from the group consisting of a copolymer having styrene
and diene monomer units, a styrene homopolymer and mixtures
thereof.
[0012] Yet another embodiment of the invention is a waterproofing
composition. The waterproofing composition includes; a) about 50 to
about 150 phr of an organic solvent, b) about 30 to 50 phr of a
coumarone-indene polymer, c) about 50 to 70 phr of a styrene
polymer, having a styrene content of about 60 wt % or greater,
selected from the group consisting of a copolymer having styrene
and diene monomer units, a styrene homopolymer and mixtures
thereof.
[0013] The above summary of the present invention is not intended
to describe each disclosed embodiment or every implementation of
the present invention. The detailed description which follows more
particularly exemplify these embodiments, but do not limit the
scope of the invention, as defined by the claims.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0014] The present invention is believed to be applicable to
methods and coating compositions for waterproofing and/or sealing a
surface of a substrate. In particular, the present invention is
directed to methods and coating compositions using a combination of
a) a hydrocarbon resin and b) one or more styrene polymers, having
a styrene content of about 60 wt % or greater, and having styrene
monomer units and usually, but not necessarily, diene monomer units
or olefin monomer units or mixtures of these polymers. While the
present invention may not be so limited, an appreciation of various
aspects of the invention will be gained through a discussion of the
examples provided below.
[0015] The term "polymer" includes homopolymers and copolymers,
unless otherwise indicated.
[0016] The term "hydrocarbon resin" is a term that is used to
describe a low molecular weight thermoplastic polymer synthesized
via the thermal or catalytic polymerization of coal-tar fractions,
cracked petroleum distillates, terpenes, or pure olefinic
monomers.
[0017] The term "monomer unit" indicates a unit of a polymer which
is derived from or has the same chemical structure as a unit
derived from a particular monomer.
[0018] The term "phr", as used herein, is a unit of measurement
which indicates the number of parts by weight of a particular
component in a coating composition having 100 parts by weight of a
polymeric binder resin.
[0019] The term "substrate" includes any surface that is capable of
being coated with the composition of the invention.
[0020] A preferred substrate is a "structural unit." The term
"structural units" includes, by way of example, foundations,
basement walls, retaining walls, cement posts, other building
walls, dry wall, pool enclosures, tub and shower enclosures,
highway structures (e.g., posts and walls), wooden or metal fence
posts, sheet rock, plywood, wafer board, wall sheeting, pressed
board, containment basins and walls, fabricated walls, floor
panels, roofs, plaza decks, decks, floors, concrete, pre-stressed
concrete other substrates that are buried or are exposed to water
or weathering conditions, and the like. These structural units are
typically made from masonry, cement, wood, plaster, stone, gypsum,
clay, brick, tile, terra cotta, cardboard, paper, and the like.
[0021] A coating composition for waterproofing or sealing a
structural unit or any other substrate has a polymeric binder resin
in an organic solvent. In addition, the coating composition may
optionally have a filler, a pigment or dye, and/or a plasticizer.
Other optional components of the coating composition include, for
example, an antioxidant, a UV (ultraviolet) absorber or blocker, an
ozone blocker, a foaming agent, a tackifier, a perfume, and/or a
deodorizer. Typically, the coating composition includes 100 parts
by weight of a polymeric binder resin, about 20 to 400 phr of an
organic solvent, 0 to about 600 phr of a filler, 0 to about 10 phr
of a pigment or dye, and 0 to about 50 phr of a plasticizer. Other
optional components of the coating composition are typically
available in amounts ranging from 0 to about 10 phr.
[0022] The polymeric binder resin is a combination of (a) a
hydrocarbon resin and (b) one or more styrene polymers, having a
styrene content of about 60 wt % or greater, and having styrene
monomer units and usually, but not necessarily, diene monomer units
or olefin monomer units or mixtures of these polymers. The
components of the binder resin are chosen based on the desired
properties of the composition and resulting film.
[0023] The use of a hydrocarbon resin component in the polymeric
binder resin is cost efficient by reducing the required amount of
more costly polymeric components in the polymeric binder
composition. The use of the hydrocarbon resin also reduces the
amount of volatile organic components (VOCs) needed in the
composition. This reduction of solvent directly lowers VOC
emissions during all stages of the production, storage and
application process of the coating composition. The hydrocarbon
resin further improves the processability of the polymeric binder
resin by lowering the overall molecular weight and viscosity of the
resin. The lower viscosity aids in the application of the resin to
the substrate. The use of a hydrocarbon resin also improves the
flexoral modulus, and gives lower gas and vapor permeation rates to
the resulting film. The hydrocarbon resin enhances the adhesive and
elongation properties of the composition and resulting film. The
resulting film is a non-tacky, flexible, and tough coating. The
hydrocarbon resin also promotes compatibility of the components in
the composition. Any amount of hydrocarbon resin in the polymeric
binder resin provides the above mentioned advantages.
[0024] The styrene component of the polymeric binder resin provides
hardness and durability to a film formed from the coating
composition. The diene component increases the flexibility and the
impact resistance of the resulting film. The olefin component gives
the film increased elasticity and resistance to oxidation and
degradation due to, for example, ultraviolet light, ozone, and
other chemical agents in the atmosphere or soil.
[0025] Hydrocarbon Resin
[0026] Hydrocarbon resins used in accordance with the invention are
low molecular weight polymers (oligomers) produced from by-product
hydrocarbon, petroleum or coal tar streams. Polymerization is
carried out using any one of a number of acid catalysts or as a
free radical reaction using heat and pressure. The hydrocarbon
resins include both natural and synthetic types; aliphatic and
aromatic. Preferred hydrocarbon resins include coumarone-indene
resins. Molecular weights of the hydrocarbon resins range from
about 200 up to about 2000, and preferably range from about 350 to
about 1000.
[0027] Coumarone-indene resins (polymers) suitable for use in the
blends of this invention generally can include those resins
obtained through catalytic polymerization of coal-tar naphthas.
Although named after two particular components of these resins,
coumarone (I) and indene (II), these resins are actually produced
by the cationic polymerization of predominantly aromatic
feedstocks. These feedstocks, such as, coal-tar naphthas contain
resin-forming materials, for example, styrene, coumarone, indene,
methyl coumarones, methyl indenes, dimethylcoumarones,
dicyclopentadiene, methyl cyclopentadienes, cyclohexadienes,
naphthalene, and anthracene derivatives. 1
[0028] Polymerization of these resin-forming materials is effected
by the catalytic action of a Bronsted acid, such as sulfuric acid
or a derivative thereof, or of a Lewis acid, such as stannic
chloride, antimony pentachloride, aluminum chloride, titanium
tetrachloride, or boron trifluoride, on the coal tar naphthas. The
polymers, generally, are not homopolymers, but are derived from
mixtures of several resin-forming materials. The polymers may also
be condensed with phenol and derivatives thereof, or with lower
aliphatic aldehydes such as formaldehyde, or may be hydrogenated to
remove residual unsaturation. Such hydrocarbon resins are
commercially available and include, for example, polyindenes,
polycoumarones, coumarone-indene polymers, phenol-modified
coumarone-indene polymers, coumarone-indene-styrene polymers,
styrene-cyclopentadiene polymers, styrene-indene polymers,
dicyclopentadiene resins, terpene resins, naphthalenic resins,
anthracenic resins, lignin and the like.
[0029] Any amount of hydrocarbon resin added to the polymeric
binder resin improves the polymeric binder resin properties as
stated above. Typically the hydrocarbon resin may be present in the
polymeric binder resin in an amount up to about 85 phr and
preferably up to about 65 phr. Further useful ranges of hydrocarbon
resin present in the polymeric binder resin include about 10 to 50
phr and more preferably 30 to 50 phr.
[0030] The most preferred hydrocarbon resins are commercially
available modified coumarone-indene polymers including, for
example, Nevex.RTM. 100 and Cumar.RTM. from Neville Chemical
Company. Vantack.RTM. 85, 95 and 105 series resins from Vanderbilt
Chemical Co., may also be used.
[0031] Polymers
[0032] The polymer typically includes a combination of up to three
types of polymers. These three types include a) styrene-diene
copolymers having a styrene content of 60 wt. % or greater and
typically from about 85 to 99 wt. % and, preferably, from about 90
to 99 wt. %, b) a copolymer having styrene and olefin monomer units
with a styrene content of 60 wt. % or greater, and c) polymers
having styrene monomer units with a styrene content of 60 wt. % or
greater and typically from about 85 to 99 wt. % and preferably,
from about 90 to 99 wt. %. The combination of polymers are
typically chosen to produce a durable film with elastomeric
properties.
[0033] The amounts of each type of polymer in the polymeric binder
resin may be representative of a single polymer or copolymer or a
combination of polymers and/or copolymers. The polymers used in the
polymeric binder resin may be virgin polymers, reground polymers,
recycled polymers, or mixtures thereof.
[0034] Typical diene monomer units include butadiene and isoprene.
Butadiene is the preferred diene monomer unit. Typical olefin
monomer units include ethylene, propylene, butylene (i.e., 1-butene
and isomers), and isobutylene (i.e., isobutene). Preferred olefin
monomer units include ethylene, butylene, and isobutylene.
[0035] The polymeric binder resin includes a polymer having a
relatively high styrene-content (styrene content greater than 60
wt. %.) The high-styrene content polymer may increase the hardness
and durability of a film formed from the coating composition. This
high styrene-content polymer may be a styrene homopolymer or a
copolymer of styrene with, for example, one or more diene, olefin,
acrylonitrile, and/or acrylate monomer units. Suitable high
styrene-content polymers include, for example, polystyrene
homopolymer, high impact polystyrene (HIPS), and medium impact
polystyrene (MIPS). Both HIPS and MIPS are often copolymers of
styrene and a diene, such as butadiene. HIPS and MIPS typically
have a styrene content that ranges from 60 wt. % to 99 wt. %.
Typically HIPS has a styrene content of least about 85 wt. % and
preferably at least about 90 wt. %. Typically MIPS has a styrene
content of least about 85 wt. % and preferably at least about 95
wt. %.
[0036] The impact resistance of films formed using coating
compositions having high styrene-content polymers typically
increases as the overall diene content increases. The diene content
of the coating composition may be modified, for example, by using a
polymer with higher diene-content or decreasing the amount of the
high styrene-content polymer in the polymeric binder resin. The
impact resistance of the film may also be modified by the addition
of a plasticizer. On the other hand, the hardness of films formed
using these polymers typically decreases as the diene content
increases. Thus, the desired properties of the film may be tailored
by varying the polymeric binder resin composition.
[0037] Polymers with styrene a content of less than 60 wt % may be
optionally added to the polymeric binder resin. These polymers
include styrene-diene copolymers and styrene-olefin copolymers. One
example of a suitable styrene-diene copolymer is a
styrene-diene-styrene triblock copolymer which has two endblocks of
polymerized styrene monomer units separated by a central block of
polymerized diene monomer units. Suitable triblock polymers
include, for example, styrene-butadiene-styrene (S-B-S) polymers
and styrene-isoprene-styrene (S-I-S) polymers. Commercial S-B-S and
S-I-S polymers include, for example, many of the Kraton.RTM. D 1100
Series polymers from Shell Chemical Company (Houston, Tex.) and
Stereon.RTM. Block Copolymers from Firestone Synthetic Rubber &
Latex Co. (Akron, Ohio). For example, Kraton.RTM. D 1101 and D 1102
are S-B-S polymers and Kraton.RTM. D 1107 is an S-I-S polymer.
These copolymers typically have a styrene-content of about 5 to 60
wt % and usually about 10 to 35 wt %.
[0038] Another example of a suitable styrene-diene copolymer is a
styrene-diene diblock polymer, such as a styrene-butadiene (S-B)
copolymer or a styrene-isoprene (S-I) copolymer. Commercially
available triblock polymers often include at least some diblock
polymer.
[0039] The styrene-diene copolymer portion of the polymeric binder
resin may include at least one block copolymer. Random copolymers
may also be used, particularly in combination with a block
copolymer or copolymers.
[0040] The polymeric binder resin may include at least one
styrene-olefin copolymer with a typical styrene-content less than
60 wt. % and preferably ranging from about 10 to 60 wt. %, and more
preferably, about 20 to 50 wt. %. Such copolymers combine the
hardness of the styrene monomer units with the elastomeric
properties of the olefin monomer units. The styrene-olefin
copolymer portion of the polymeric binder resin typically includes
at least one block copolymer, however, random copolymers may also
be used, particularly in combination with block copolymers.
Examples of styrene-olefin copolymers include
styrene-ethylene-butylene-styrene (S-EB-S) block copolymers,
styrene-ethylene-propylene-styrene (S-EP-S) block copolymers,
styrene-ethylene-butylene (S-EB) block copolymers, and
styrene-ethylene-propylene (S-EP) block copolymers. Examples of
these copolymers include Kraton.RTM. G 1600 and 1700 series
polymers and Kraton.RTM. FG 1900 series polymers. A preferred
polymer of this type is the styrene-ethylene-butylene-styrene
polymer, such as, for example, many of the Kraton.RTM. G 1600
Series polymers, including Kraton.RTM. G 1650 and 1652
polymers.
[0041] The polymeric binder resin may additionally include at least
one polyolefin. Suitable examples of polyolefins include
polyethylene, polypropylene, and polybutene. Preferred polyolefin
include polyethylene, polybutene, polyisobutylene, and polymers
having a combination of butylene and isobutylene monomer units
(e.g., a polymer having about 25 to 30 wt. % isobutylene monomer
units and about 70 to 75 wt. % butylene monomer units) .
Polyolefins may be obtained from a variety of manufacturers and
distributors.
[0042] In one embodiment of the invention, the polymeric binder
resin includes: a) about 1 to 85 phr hydrocarbon resin: b) about 15
to 99 phr of a styrene polymer, having a styrene content of about
60 wt % or greater, selected from the group consisting of a
copolymer having styrene and diene monomer units, a styrene
homopolymer and mixtures thereof.
[0043] In another embodiment of the invention, the polymeric binder
resin includes: a) about 1 to 65 phr, preferably about 10 to 50 phr
coumarone-indene polymer; b) about 35 to 99 phr, preferably about
50 to 90 phr of a styrene polymer, having a styrene content of
about 60 wt % or greater, selected from the group consisting of a
copolymer having styrene and diene monomer units, a styrene
homopolymer and mixtures thereof.
[0044] In another embodiment of the invention, the polymeric binder
resin includes: a) about 30 to 50 phr coumarone-indene polymer; b)
about 50 to 70 phr of a styrene polymer, having a styrene content
of about 60 wt % or greater, selected from the group consisting of
a copolymer having styrene and diene monomer units, a styrene
homopolymer and mixtures thereof.
[0045] Solvent
[0046] The polymers and hydrocarbon resins that form the polymeric
binder resin are dissolved and/or dispersed in an organic solvent
to form a coating composition. The amount of solvent used
determines the drying time, and appropriate method of application
for the coating composition. A variety of solvents may be used.
Suitable solvents which are commonly used include, for example,
aromatic hydrocarbons, cycloaliphatic hydrocarbons, terpenes,
unsaturated hydrocarbons, organic carbonates, and halogenated
aliphatic and aromatic hydrocarbons. Suitable solvents include
toluene, xylene, benzene, halogenated benzene derivatives, ethyl
benzene, mineral spirits, naphtha, cyclohexane, methylene chloride,
ethylene chloride, trichlorethane, chlorobenzene, propylene,
ethylene carbonate, nitropropane, acetone, ethyl acetate, propyl
acetate, butyl acetate, and isobutyl isobutyrate. Preferred
solvents are aromatic hydrocarbons, such as toluene, xylene,
benzene, and halogenated benzene derivatives, as well as mineral
spirits.
[0047] For environmental reasons, it is desirable to use as little
solvent as possible in the coating composition. The lower limit on
the amount of solvent may be determined by the amount of solvent
needed to solvate and/or disperse the components of the coating
composition. If too little solvent is used, then the coating
composition may be too viscous for the particular application. On
the other hand, if too much solvent is used, the coating
composition may not have the necessary viscosity to ensure that a
proper coating is deposited on the structural unit and an excessive
amount of VOCs are emitted into the environment. This can result in
a film that may be thin, easily punctured, and/or have an
unacceptable amount of pinholing. In addition to the use of a
solvent, the viscosity of a coating composition may often be
reduced by warming the coating composition. Surprisingly, the
addition of hydrocarbon resins to the composition reduces the
amount of solvent needed to solvate and/or disperse the components
of the coating composition.
[0048] The use of the hydrocarbon resin reduces the amount of
solvent or volatile organic components (VOCs) needed in the
composition for a specified final film thickness. Coating a set
area with a specified film thickness emits less VOCs with the
hydrocarbon resin included in the coating composition than without
the hydrocarbon resin in the coating composition. This reduction of
solvent directly lowers VOC emissions during application of the
coating composition to a substrate. Lower solvent emissions during
application of the coating composition is a surprising benefit
gained by using a hydrocarbon resin in the coating composition.
[0049] The desired viscosity of the coating composition often
depends on the method of application of the coating composition.
Coating compositions that are formulated for application using a
brush or roller can often be more viscous than those formulated for
spraying. The desired viscosity may also depend on whether the
surface to be coated is a vertical surface, where a less viscous
coating composition may run, or a horizontal surface.
[0050] The amount of solvent in the coating composition typically
ranges from about 20 to 400 phr, preferably from about 33 to 250
phr, and more preferably from about 50 to 150 phr, based on 100
part by weight of the polymeric binder resin. However, larger or
smaller amounts of solvent may be used depending on the desired
composition and viscosity of the coating composition.
[0051] Optional Components
[0052] The coating composition typically includes a filler. The
filler may increase the strength of the coating composition and/or
replace costly materials of the polymeric binder resin. The filler
may also modify the physical properties of the coating composition
and films formed using the coating composition, including, for
example, the color, opacity, affinity for other coatings, density,
rheology, stiffness, and modulus of the coating composition and/or
film. Any particular filler may have one or more of these, or
other, functions in the coating composition.
[0053] In addition, a coating composition with a filler may more
easily and reliably cover holes, depressions, recesses, cracks, and
crevices in a substrate, for example, in masonry blocks, concrete,
wood, and other porous or rough substrates. The presence of a
filler may reduce the size and number of pinholes in a film formed
from the coating composition. These pinholes arise, at least in
some cases, because of gravity and/or capillary action that draws
the coating composition into the hole, depression, recess, crack,
or crevice in the substrate, creating a break or pinhole in the
resulting film. The filler often includes particles that, because
of their larger size, provide structural support that, in
combination with the polymeric binder resin, forms a film across
the hole, depression, recess, crack, or crevice. This reduces the
tendency to form pinholes.
[0054] Surprisingly, the use of a hydrocarbon resin also increases
the amount of filler that can be added to the coating
composition.
[0055] Suitable fillers include, for example, carbonates, clays,
talcs, silicas including fumed silica and amorphous silica,
silico-aluminates, aluminum hydrate, metal oxides (e.g., oxides of
aluminum, iron, zinc, magnesium, and titanium), silicates (e.g.,
mica), sand, Portland cement, carbon filaments, glass, fiberglass,
cellulose, graphite, mortar powder, calcium carbonate, sulfates
(such as magnesium or calcium sulfates), and the like. Additional
suitable fillers include, for example, polymeric materials such as
vinyl and other rubbers, nylon, rayon, polyesters, and the like, as
well as combinations thereof, particularly combinations of rubber
and the other components. These polymeric materials may be virgin,
reground or recycled and may include pellets, milled or cut fibers,
and other forms of the polymers. These polymeric materials do not
participate in the polymeric binder resin. Preferred fillers
include titanium dioxide, oxides, clay, mica, talc, vinyl rubber,
nylon, rayon, polyesters, graphite, and mixtures thereof.
[0056] The amount of filler in the coating composition typically
depends on the desired properties of the composition. These
properties may include the strength, flexibility, ultraviolet
radiation resistance, chemical resistance, permeability, and cost
of the coating composition. Often more than one type of filler is
used. A combination of fillers may provide desired advantages for
the coating composition and/or overcome disadvantages arising from
other components in the film. Typically, the amount of filler
ranges from 0 to about 600 phr, preferably about 10 to 150 phr,
more preferably, about 20 to 100 phr, and most preferably about 25
to 80 phr, based on 100 parts by weight of the polymeric binder
resin. Larger amounts of filler may also be used. However, if the
amount of filler is too large then the polymeric binder resin may
not be sufficient to hold together the film formed from the coating
composition.
[0057] In some embodiments, the coating composition contains about
5 to 60 phr, and preferably about 20 to 50 phr, of a polymeric
filler material, such as vinyl rubber, nylon, polyester, rayon, or
combinations thereof. These polymeric filler materials often
enhance the sprayability and wearability of the resulting coating
compositions and films.
[0058] In some embodiments, the coating composition contains about
0.1 to 20 phr, and preferably about 5 to 15 phr, of a metallic
oxide. The preferred metallic oxide is titanium dioxide.
[0059] In addition, some embodiments contain about 1 to 35 phr, and
preferably about 5 to 25 phr, of a silicate, such as mica. Mica has
been found to be particularly useful in reducing the size and
number of pinholes.
[0060] The coating composition may optionally include a pigment or
dye. The pigment or dye may impart a desired color to the coating
composition and may be added for aesthetic purposes. The pigment or
dye may also be included in the coating composition to, for
example, aid the user in determining which portion of a surface has
been covered by the coating composition. The pigment or dye may
also absorb light which can harm the film. For example, the pigment
or dye may absorb one or more wavelengths of ultraviolet (UV)
light.
[0061] Pigments and dyes may be powders, lakes, metal flakes,
organic or organometallic molecules, and the like. Examples of
suitable pigments and dyes include iron lakes, iron oxide, such a
red, yellow, and black iron oxides, other metal oxides, and carbon
black. Typically, 0 to about 10 phr, and preferably about 0.1 to 3
phr, of pigment or dye is used. However, larger amounts may be
used. In addition to compounds used primarily as pigments or dyes,
the coating composition may also include other components, such as
the filler material, that also act as a pigment or dye. For
example, titanium dioxide which may also be a filler, is a pigment.
In such cases, the amount of the filler/pigment (e.g., titanium
dioxide) in the coating composition may be representative of that
described above for the filler material.
[0062] Another optional additive is an antioxidant. Polymers with
styrene and diene monomer units are unsaturated and are susceptible
to attack by oxygen. An antioxidant may be added to the coating
composition to prevent the oxidation of the polymers in the
polymeric binder resin. In some commercial polymers, an antioxidant
is already provided with the polymer and additional antioxidant may
not be needed. For example, commercial styrene-containing and
diene-containing polymers, including the Kraton.RTM. Series D 1100
and G 1600 polymers, already have an amount of antioxidant added to
the polymer to facilitate manufacturing, shipping, and storage.
However, additional antioxidant may be added as desired or
needed.
[0063] A variety of antioxidants are known and may be included in
the coating composition. One suitable type of antioxidant includes
a substituted phenolic compound. Commercial antioxidants of this
type include Irganox.RTM. 1010 and 565 (Ciba-Geigy Co., Ardsley,
N.Y.), Ethanox.RTM. 330 (Ethyl Corp., Baton Rouge, La.), and BHT
(butylated hydroxytoluene, available from a variety of sources).
Other types of antioxidants may also be used.
[0064] The amount of antioxidant in the coating composition ranges
from 0 to about 10 phr. If an antioxidant is used in the coating
composition, the amount of antioxidant preferably range from about
0.01 to 5 phr, and more preferably from about 0.05 to 2 phr.
[0065] The coating composition may also include an ultraviolet (UV)
absorber or blocker. This may be particularly useful in coating
compositions that are exposed to sunlight or other sources of
ultraviolet light. Examples of suitable UV absorbers or blockers
include substituted benzotriazoles, hindered amines, benzophenones,
and monobenzoates. Commercial UV absorbers or blockers include
Tinuvin.RTM. P/300 Series and Tinuvin.RTM. 770 from Ciba-Geigy Co.
(Ardsley, N.Y.), Cyasorb.RTM. UV 531 from American Cyanamid (Wayne,
N.J.), and Eastman.RTM. RMB from Eastman Chemical Co. (Kingsport,
Tenn.). Other types of UV absorbers or blockers may also be
used.
[0066] The amount of UV absorber or blocker in the coating
composition ranges from 0 to about 10 phr. If an UV absorber or
blocker is used in the coating composition, the amount of UV
absorber or blocker preferably range from about 0.01 to 5 phr, and
more preferably from about 0.05 to 2 phr.
[0067] Ozone blockers may also be used, particularly for coating
substrates that will be exposed to air or to ozone-forming devices.
Examples of ozone blockers include dibutyl thiourea, nickel
dibutyl-dithiocarbomate (DuPont, Wilmington, Del.), Ozone Protector
80 (Reichhold Chemicals, Durham, N.C.) and the like. The amount of
ozone blocker in the coating composition ranges from 0 to about 10
phr. If an ozone blocker is used in the coating composition, the
amount of ozone blocker preferably range from about 0.01 to 5 phr,
and more preferably from about 0.05 to 2 phr.
[0068] The coating composition may also include a plasticizer. The
plasticizer may increase the toughness and flexibility of the film
resulting from the coating composition. In many cases, a
plasticizer is not needed as the combination of the polymers in the
polymeric binder resin plasticize each other. However, when desired
or needed an additional plasticizer may be added. Examples of
useful plasticizers include butyl stearate, dibutyl maleate,
dibutyl phthalate, dibutyl sebecate, diethyl malonate, dimethyl
phthalate, dioctyl adipate, dioctyl phthalate, butyl benzyl
phthalate, benzyl phthalate, octyl benzyl phthalate, ethyl
cinnamate, methyl oleate, tricresyl phosphate, trimethyl phosphate,
tributyl phosphate, trioctyl adipate phthalate esters and the like.
Other plasticizers are known.
[0069] Typically, the coating composition includes 0 to about 50
phr of plasticizer. For those embodiments that use a plasticizer,
the preferred amount ranges from about 5 to 40 phr, more preferred
from about 7 to 30 phr, and most preferred from about 10 to 20 phr.
The amount of plasticizer used in the coating composition depends,
at least in part, on the desired properties and the composition of
the polymeric binder resin. Typically, the more plasticizer, the
more elastic the film, however, if the amount of plasticizer is too
great than the cohesiveness of the film resulting from the coating
composition may decrease. A plasticizer may be particularly useful
in combination with high styrene-content polymers.
[0070] Other components may be used in the coating composition. For
example, it has been found that the addition of a small amount
(less than 0.1 phr) of colloidal silica (e.g., Cab-O-Sil.RTM. M-5
or TS-610, Cabot Corp., Tuscola, Ill.), particularly in combination
with about 1 to 10 phr of mineral spirits, causes the volume of the
coating composition and the resulting film to increase. Examples of
other optional components of the coating composition includes for
example, perfumes, deodorants, foaming agents and tackifiers (e.g.,
Wingtack.RTM. series tackifiers from Goodyear Tire & Rubber
Co., Akron, Ohio).
[0071] Preparation Methods
[0072] The coating composition is prepared by combining the organic
solvent with the other components, including the polymers, the
hydrocarbon resin, and the optional filler, pigment, antioxidant,
plasticizer, and any of the other optional components. This
combination is then mixed to dissolve and/or disperse the
components within the solvent and form the coating composition. The
mixing continues for about 30 minutes to 2 hours or until the
coating composition appears creamy and the particles in the coating
composition appear uniform as viewed through a falling film of the
coating composition.
[0073] Various modifications can be made to this procedure. In some
embodiments, the polyolefin polymer is not added until after the
mixing of the solvent and the other components begins, particularly
if the polyolefin polymer is a polybutene polymer (e.g.,
polybutylene or polyisobutylene). Polyolefin polymers, particularly
polybutylene and polyisobutylene, often do not disperse well in the
solvent unless the polyolefin polymer has been previously liquefied
by dissolving or dispersing in a solvent, such as mineral spirits,
and/or by heating. The polyolefin polymer may be added into the
solvent mixture over a period of time, for example, over a period
of 10 minutes or less. Preferably, the polyolefin polymer is heated
to a temperature ranging from about 90 to 125.degree. C. and mixed
with mineral spirits prior to being poured into the solvent
mixture, as this typically enhances dispersion of the polyolefin in
the solvent.
[0074] Furthermore, for those embodiments which have vinyl rubber
as a filler component, it may be desirable to allow the vinyl
rubber to sit in a portion of the organic solvent for fifteen
minutes to 12 hours until the vinyl rubber and the organic solvent
form a paste. This paste is typically added to the mixture with the
rest of the components before or shortly after adding the solvent.
The formation of a paste facilitates the dispersal of the vinyl
rubber filler throughout the coating composition.
[0075] Application
[0076] The coating composition can be applied by a variety of
techniques, including, for example, rolling, brushing, spraying,
squeeging, backrolling, pouring, troweling, or otherwise coating
the surface of the substrate. A preferred application technique is
spraying the coating on the substrate. Combinations of these
techniques may also be used including spraying the coating
composition on the structural unit and then rolling or brushing the
sprayed coating composition to obtain a more uniform coating. The
coating composition may be used on both interior and exterior
surfaces of structures, as well as on other surfaces that need to
be waterproofed.
[0077] Spraying the coating composition on the substrate requires a
flowable coating composition. Many physical properties affect
flowability, such as, for example, viscosity, temperature, and the
like. Usually, as the viscosity is lowered, the easier it is to
spray the coating composition. Normally as the temperature of the
material rises, the easier it is to spray the coating composition.
Coating compositions applied year round in northern latitudes
typically require special attention to maintain the flowability of
the composition.
[0078] The thickness of the coating will often depend on the
particular surface and material of the structural unit, as well as
the projected exposure to moisture. Rougher surfaces and surfaces
in areas with more moisture may require a thicker coating. In
addition, thicker coatings may be used in situations where the
coating may be subject to puncturing. For example, a coating on the
exterior of a below-grade masonry unit, such as a foundation,
should be thick enough to withstand bridging cracks that develop in
the substrate and the backfilling process. Typical dry coating
thickness range from about 5 to 100 mil (about 125 to 2500 .mu.m),
and preferably from about 40 to 60 mil (about 1000 to 1525 .mu.m).
Thicker and thinner coatings may also be used depending, in part,
on the desired use of the structural unit.
[0079] Upon drying, the coating composition becomes a film. Typical
drying times range from 4 to 24 hours. Longer or shorter drying
times may be used depending on the thickness of the applied coating
composition, the air temperature and humidity and the desired
amount of solvent that should be removed.
[0080] The coating composition of the present invention may be
applied by itself or in conjunction with another waterproofing
system. For example, the coating composition of the present
invention may be coated on a structural unit, followed by the
application of waterproofing sheeting. In addition, the coating
composition of the present invention may be used with another
coating to provide enhanced protection. A preferred coating for use
with the coating of the present invention is a
flexible-film-forming composition, such as, for example, the
compositions described in Patent application Ser. No. 09/274,180
that was filed on Mar. 23, 1999. In one embodiment, the
flexible-film-forming composition comprising an organic solvent and
a polymeric binder resin, the polymeric binder resin having a
styrene content less than 60 wt. %. Such polymers include
copolymers having styrene and diene monomer units with a styrene
content of less than 60%. wt, polymers having olefin monomer units,
copolymers having styrene and olefin monomer units with a styrene
content of less than 60%. wt and mixtures thereof. The preferred
combination of the two coating compositions includes applying the
coating composition of the present invention between the substrate
and the flexible-film-forming coating.
EXAMPLES
[0081] The following examples further illustrate the invention.
These examples are merely illustrative of the invention and do not
limit the scope of the invention.
[0082] Between one quart and several gallons of the coating
composition (Tables 1 and 2 labeled A-C) were prepared using the
following materials and amounts:
1TABLE 1 Materials and Amounts for the Coating Compositions A (kg)
Xylene 1.89 Nevex .RTM. 100 0.43 (Coumarone-indene resin) MIPS 312
0.58 (Medium Impact Polystyrene) Palitinol 79 0.13 (Plasticizer)
Opti White 0.21 (Filler) Wollastonite 0.68 (Filler) Talc 0.52
Titanium Dioxide 0.09
[0083] The polymers, hydrocarbon resin and titanium dioxide, were
combined in a vessel. The solvent (xylene and optionally mineral
spirits) was then added. The solvent and other components were
mixed for 20 to 45 minutes. The mixing continued until the mixture
appeared creamy and the particles in the mixture appeared uniform
when viewed through a falling film of the mixture. Each coating was
sprayed or brushed onto the substrate. Each coating composition was
allowed to dry on a substrate, such as a masonry block. The
resulting films were solid with a minimum of pinholing and had
elastomeric qualities.
2TABLE 2 Materials and Amounts for Coating Compositions B C (kg)
(kg) Xylene 1.89 1.89 Nevex .RTM. 100 0.43 0.00 (Coumarone-indene
resin) MIPS 312 0.58 0.58 Palitinol 79 0.13 0.13 Opti White 0.21
0.21 Wollastonite 0.68 0.68 Talc 0.52 0.52 Titanium Dioxide 0.09
0.09
[0084] Formula B shown in Table 2 illustrates another example of
the invention composition and is used in the viscosity tests that
follow (Table 3). Formula C shown in Table 2 illustrates a coating
composition without hydrocarbon resin used in the viscosity tests
that follow (Table 4). "EEEE" in Table 4 indicates a value too high
for the instrument to read.
[0085] Many of the components used in the Examples were available
from a variety of manufacturers and distributors. For example, the
Nevex 100.RTM. hydrocarbon resins were available from Neville
Chemical Company (Pittsburgh, Pa.). MIPS 312 was available from
Nova Chemicals. Palitinal 79 was available from BASF (New Jersey).
Wollastonite was available from NYCO Minerals, Inc., (Willsboro,
N.Y.). Opti White was available from Burgess Pigment Company
(Sandersville, Ga.). Talc, titanium dioxide, xylene, methylene
chloride, and mineral spirits were available from a variety of
manufacturers.
3TABLE 3 Brookfield Viscosity Results Formula B Shear Shear Speed
Torque Viscosity Stress Rate Temp Time Item # RPM % mPas N/m.sup.2
1/s .degree. C. MM:SS 1 2.5 20.6 20600 17.5 0.85 14.8 04:03 2 5.0
26.1 13050 22.2 1.70 14.8 02:00 3 10 34.2 8550 29.1 3.40 14.8 01:00
4 20 48.3 6037 41.1 6.80 14.7 00:30 5 10 34.1 8525 29.0 3.40 14.8
01:00 6 5.0 26.0 13000 22.1 1.70 14.8 02:00 7 2.5 21.1 21100 17.9
0.85 14.8 04:00
[0086]
4TABLE 4 Brookfield Viscosity Results Formula C Shear Shear Speed
Torque Viscosity Stress Rate Temp Time Item # RPM % mPas N/m.sup.2
1/s .degree. C. MM:SS 1 2.5 96.9 96900 82.4 0.85 14.8 04:01 2 5.0
EEEE EEEE EEEE 1.70 14.8 01:59 3 10 EEEE EEEE EEEE 3.40 14.8 01:00
4 20 EEEE EEEE EEEE 6.80 14.8 00:30 5 10 EEEE EEEE EEEE 3.40 14.8
01:00 6 5.0 100 50350 85.5 1.70 14.7 02:00 7 2.5 91.6 91600 77.9
0.85 14.8 04:00
[0087] The present invention should not be considered limited to
the particular examples described above, but rather should be
understood to cover all aspects of the invention as fairly set out
in the attached claims. Various modifications, equivalent
processes, as well as numerous structures to which the present
invention may be applicable will be readily apparent to those of
skill in the art to which the present invention is directed upon
review of the instant specification.
* * * * *