WO2022133786A1

WO2022133786A1 - A method of reducing the drying time of a coating composition and coating compositions having reduced drying time

Info

Publication number: WO2022133786A1
Application number: PCT/CN2020/138569
Authority: WO
Inventors: Jitao CHEN; Tong Sun; Tao Wang; Jian Li; Xiaohong Zhang; Yi Cheng
Original assignee: Dow Global Technologies Llc
Priority date: 2020-12-23
Filing date: 2020-12-23
Publication date: 2022-06-30
Also published as: CN116685647A

Abstract

The present disclosure relates to a method of reducing the drying time of a coating composition, comprising adding a multiple-functional composite to the coating composition, wherein the multiple-functional composite is spray-dried composite particles comprising by dry weight based on total dry weight of the spray-dried composite particles, from 60% to 90% of inorganic extenders, from 5% to 25% of inorganic pigments, and from 3% to 20% of water-insoluble polymer particles, wherein the coating composition comprises an aqueous emulsion of acrylic polymer. The present disclosure also relates to a use of multiple-functional composite in reducing the drying time of a coating composition and compositions having reduced drying time.

Description

A METHOD OF REDUCING THE DRYING TIME OF A COATING COMPOSITION AND COATING COMPOSITIONS HAVING REDUCED DRYING TIME

FIELD OF THE INVENTION

The present disclosure relates to a method of reducing the drying time of a coating composition, a use of multiple-functional composite in reducing the drying time of a coating composition and coating compositions having reduced drying time.

INTRODUCTION

One component (1K) polymeric waterproofing coatings are typically formulated with flexible latex polymers, pigments/extenders as well as additives such as dispersant, thickener, defoamers, and the like. They are mainly used for exterior building surfaces such as roofs and exterior walls as well as some interior building rooms such as bathrooms and kitchens. Among various kinds of 1K polymeric waterproofing coatings, elastomeric roof coatings (ERC) and elastomeric wall coatings (EWC) are liquid applied membranes formed in-situ on a roof or a wall. Elastomeric roof coatings (ERC) and elastomeric wall coatings (EWC) usually use low Tg acrylic latexes in the formulation together with TiO ₂, CaCO ₃, ZnO and BaSO ₄ as the key pigments/extenders to get balanced mechanical property as well as water resistance. However, the liquid applied wet coating films need longer time to cure (including surface dry and fully dry) , especially under high humidity conditions due to the slower rate of water evaporation for low Tg polymer emulsions. Sometimes, the coating applicators are also required to get fast dry polymeric coatings under normal working condition because accelerated drying could allow applicators to complete the required two or more coating layers in a shorter time to improve working efficiency and save labor cost. The relatively higher thickness of waterproofing coatings when applied at jobsite also makes the fast-dry requirement more challenging. It is important to develop a method of reducing the drying time of waterproofing coating compositions.

Commercially available fast-dry or quick-set approach is mainly related to post-adding additives to existing polymer emulsions. To address the need for more rapid set times with a single formulation, systems have been developed that utilize pH triggered chemistry to set up. The system remains stable when basic and then sets up when the pH drops. The pH drop is triggered after application of the system as volatile base evaporates from the system thereby lowering the pH of the system. See, for example, the systems of US5527853, US5861188, US6013721 and US2015/0259559 which disclose anionically stabilized polymer particles in combination with poly-functional amine polymers that are stabilized by volatile base. As the volatile base evaporates the system ceases to be stabilized and the polymer particles react with the amine functionalities to set up the system. For example, Primal ^TM EC-1791QS is the fast cure version for Primal ^TM EC1791 latex used in elastomeric roof coatings. A poly-functional amine polymer additive is post-added into Primal ^TM EC1791 with pH adjusted to higher than 10 by aqueous ammonia. Another commercial fast-cure approach is polyethylenimine (PEI) based additive which could be added into formulations if fast-cure function is desired. However, above fast-dry or quick-set approaches have drawbacks such as unpleasant aqueous ammonia odor, more complicated formulation expertise and potential formulation compatibility issue.

Therefore, there is a need in the art for a new method for reducing the drying time of a coating composition.

After persistent exploration, the inventors of the present disclosure have surprisingly found that the addition of a multiple-functional composite to a coating composition can reduce the drying time, especially full drying time, of the coating composition, preferably, at the same time, the mechanical properties including tensile strength and elongation at break are maintained at the same level or an acceptable level and the water absorption are kept at an acceptable level, and the viscosity of the coating composition is increased. Based on these findings, the inventors developed a method of reducing the drying time of a coating composition, a use of multiple-functional composite in reducing the drying time, especially full drying time, of a coating composition and several coating compositions including elastomeric roof coating compositions, elastomeric wall coating compositions, two component cementitious waterproofing coating compositions and a stucco coating compositions, which has reduced drying time while remaining a tensile strength and elongation at break and a water absorption at an acceptable level.

SUMMARY OF THE INVENTION

In a first aspect of the present disclosure, the present disclosure provides a method of reducing the drying time of a coating composition, comprising adding a multiple-functional composite to the coating composition,

wherein the multiple-functional composite is spray-dried composite particles comprising by dry weight based on total dry weight of the spray-dried composite particles, from 60%to 90%of inorganic extenders, from 5%to 25%of inorganic pigments, and from 3%to 20%of water-insoluble polymer particles; and

wherein the coating composition comprises an aqueous emulsion of acrylic polymer.

Preferably, said acrylic polymer has at least one structural unit of one or more ethylenically unsaturated monomers carrying at least one heterofunctional group.

Preferably, the coating composition is selected from the group consisting of an elastomeric roof coating composition, an elastomeric wall coating composition, a two-component cementitious waterproofing coating composition, and a stucco coating composition.

In a second aspect of the present disclosure, the present disclosure provides a use of a multiple-functional composite in reducing the drying time of a coating composition, wherein the multiple-functional composite is spray-dried composite particles comprising by dry weight based on total dry weight of the spray-dried composite particles, from 60%to 90%of inorganic extenders, from 5%to 25%of inorganic pigments, and from 3%to 20%of water-insoluble polymer particles;

wherein the coating composition comprises:

(a) an aqueous emulsion of acrylic polymer; and

(b) the multiple-functional composite.

In a third aspect of the present disclosure, the present disclosure provides an elastomeric roof coating composition or an elastomeric wall coating composition comprising:

i) an aqueous emulsion of acrylic polymer; and

ii) a multiple-functional composite;

wherein the multiple-functional composite is used in an amount of 11%or more by weight based on the total weight of the coating composition.

In a fourth aspect of the present disclosure, the present disclosure provides a two-component cementitious waterproofing coating composition comprising:

A) a liquid part comprising an aqueous emulsion of acrylic polymer;

B) a powder part comprising

B1) a cementitious material, and

B2) a multiple-functional composite;

wherein the multiple-functional composite is spray-dried composite particles comprising by dry weight based on total dry weight of the spray-dried composite particles, from 60%to 90%of inorganic extenders, from 5%to 25%of inorganic pigments, and from 3%to 20%of water-insoluble polymer particles.

In a fifth aspect of the present disclosure, the present disclosure provides a stucco coating composition comprising:

i) an aqueous emulsion of acrylic polymer;

ii) a multiple-functional composite; and

iii) a silica sand;

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 shows the surface morphology of Examples in Table 8.

DETAILED DESCRIPTION OF THE INVENTION

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the invention belongs. Also, all publications, patent applications, patents, and other references mentioned herein are incorporated by reference.

The numerical ranges disclosed herein include all values from, and including, the lower and upper value. For ranges containing explicit values (e.g., 1 or 2; or 3 to 5; or 6; or 7) , any subrange between any two explicit values is included (e.g., 1 to 2; 2 to 6; 5 to 7; 3 to 7; 5 to 6; etc. ) . Unless stated to the contrary, implicit from the context, or customary in the art, all parts and percentages are based on weight and all test methods are current as of the filing date of this disclosure.

As disclosed herein, the term "composition" , "formulation" or "mixture" refers to a physical blend of different components, which is obtained by mixing simply different components by a physical means. The sum of the percentages by weight of each component in a composition is 100 wt%, based on the total weight of the composition.

As used herein, the term “average particle size” refers to the median particle size or diameter of a distribution of particles as determined for example, by a Multisizer ^TM 3 Coulter Counter ^TM (Beckman Coulter, Inc., Fullerton, CA) according to the procedure recommended by the manufacturer. The median particle size is defined as the size wherein 50 wt%of the particles in the distribution are smaller than the median particle size and 50 wt%of the particles in the distribution are larger than the median particle size. It is a volume average particle size.

As disclosed herein, “and/or” means “and, or as an alternative” . All ranges include endpoints unless otherwise indicated.

An aqueous emulsion of acrylic polymer

The aqueous emulsion of acrylic polymer can be prepared through free radical emulsion or suspension polymerization or by dispersion of a pre-formed polymer under shear into an aqueous medium. Monomers suitable for the preparation of the acrylic polymer include, but are not limited to, (meth) acrylic acids and (meth) acrylates, such as alkyl (meth) acrylates. Examples of alkyl (meth) acrylates are, but not limited to, methyl acrylate, ethyl acrylate, butyl acrylate, glycidyl methacrylate, 2-ethylhexyl acrylate, methyl methacrylate, ethyl methacrylate, butyl methacrylate, and 2-ethylhexyl methacrylate, and combinations thereof. The acrylic polymer may comprise, based on the weight of the polymer, from 0.1%to 10%by weight, from 0.5%to 8%by weight, from 0.8%to 5%by weight, or from 1%to 3%by weight, of structural units of (meth) acrylic acids. The acrylic polymer may comprise, based on the weight of the polymer, from 10%to 100%by weight, from 15%to 99%by weight, from 20%to 95%by weight, from 30%to 80%by weight, or from 40%to 75%by weight, of structural units of alkyl (meth) acrylates.

The acrylic polymer in the present disclosure may comprise structural units of one or more ethylenically unsaturated monomers carrying at least one heterofunctional group. The heterofunctional group may be selected from the group consisting of ureido, nitrile, amide, hydroxyl, alkoxysilane (preferably hydrolyzable alkoxysilane) , or phosphorous group. Preferably, the heterofunctional group may be selected from the group consisting of ureido, nitrile and amide. Suitable ureido functional monomer includes, for example, ureido group containing (meth) acrylic acid alkyl esters. Examples of suitable ureido monomers are illustrated below:

or mixtures thereof. Representative functional monomer like Norsocryl 104 can be obtained from Arkema. Suitable alkoxysilane functional monomer includes, for example, vinyltrialkoxysilanes such as vinyltrimethoxysilane; alkylvinyldialkoxysilanes; (meth) acryloxyalkyltrialkoxysilanes such as (meth) acryloxyethyltrimethoxysilane and (meth) acryloxypropyltrimethoxysilane; derivatives thereof, and combinations thereof. Preferred alkoxysilane functional monomer is Silquest A-171 available from Momentive. Suitable nitrile functional monomer includes, for example, (alkyl) acrylonitrile, such as (meth) acrylonitrile. Suitable amide functional monomer includes, for example, (alkyl) acrylamide, such as (meth) acrylamide. Suitable phosphorous functional monomer includes, for example, phosphorous-containing (meth) acrylates, such as phosphoethyl (meth) acrylate, phosphopropyl (meth) acrylate, phosphobutyl (meth) acrylate, salts thereof, and mixtures thereof; CH ₂=C (R) -C (O) -O- (R _lO) _n-P (O) (OH) ₂, wherein R=H or CH ₃, R ₁=alkyl, and n=2-6, such as SIPOMER PAM-100, SIPOMER PAM-200, and SIPOMER PAM-300 all available from Solvay; phosphoalkoxy (meth) acrylates such as phospho ethylene glycol (meth) acrylate, phospho di-ethylene glycol (meth) acrylate, phospho tri-ethylene glycol (meth) acrylate, phospho propylene glycol (meth) acrylate, phospho di-propylene glycol (meth) acrylate, phospho tri-propylene glycol (meth) acrylate, salts thereof, and mixtures thereof. Preferred phosphorous-containing (meth) acrylate is ethylene glycol methacrylate phosphate from producers like Hangzhou Hairui Chemical Co., Ltd. Suitable hydroxy functional monomer includes, for example, hydroxyethyl (meth) acrylate and hydroxypropyl (meth) acrylate. The alkyl mentioned above is preferably C1-C10 alkyl, more preferably C1-C6 alkyl, or even more preferably C1-C4 alkyl.

The acrylic polymer may comprise, based on the weight of the polymer, from 0.1%to 20%by weight, from 0.5%to 15%by weight, from 1%to 12%by weight, or from 1.5%to 10%, or from 1.5 %to 5%, by weight, of structural units of one or more ethylenically unsaturated monomers carrying at least one heterofunctional group.

The acrylic polymer may further comprise structural units of one or more styrene monomers. The styrene monomers may include, for example, styrene, substituted styrene, or mixtures thereof. The substituted styrene may include, for example, benzyl acrylate, 2-phenoxyethyl acrylate, butylstyrene, methylstyrene, p-methoxystyrene, or mixtures thereof. Preferred styrene monomer is styrene. The polymer may comprise, by weight of the polymer, 1%or more, 5%or more, 10%or more, 15%or more, 17%or more, 19%or more, or even 21%or more, and at the same time, 40%or less, 35%or less, 30%or less, 28%or less, or even 26%or less, of structural unit (s) of the styrene monomer (s) .

The polymer useful in the present disclosure may be prepared by free-radical polymerization, preferably emulsion polymerization, of the monomers described above. Emulsion polymerization is a preferred process. Total weight concentration of the monomers for preparing the polymer is equal to 100%. A mixture of the monomers may be added neat or as an emulsion in water; or added in one or more additions or continuously, linearly or nonlinearly, over the reaction period of preparing the polymer. Temperature suitable for emulsion polymerization processes may be lower than 100℃, in the range of from 30 to 95℃, or in the range of from 50 to 90℃.

In one embodiment, the aqueous emulsion of acrylic polymer is PRIMAL ^TM EC 4642, PRIMAL ^TM EC 4811, PRIMAL ^TM EC 2848ER, PRIMAL ^TM AC261P, PRIMAL ^TM EC 1791, PRIMAL ^TM EC 1791QS, TIANBA ^TM 2012 available from the Dow Chemical Company.

The acrylic polymer in the present disclosure may have a weight average molecular weight of from 10,000 to 1,000,000, from 20,000 to 700,000, or from 40,000 to 500,000. The weight average molecular weight may be measured by gel permeation chromatography (GPC) calibrated by the polystyrene standard.

The acrylic polymer useful in the present disclosure may have a Fox Tg of -50 ℃ or higher, -40 ℃ or higher, -30 ℃ or higher, -25 ℃ or higher, or even -20 ℃or higher, and at the same time, 30 ℃ or less, 20 ℃ or less, 10 ℃ or less, 0 ℃ or less, -4 ℃ or less, or even -5 ℃ or less.

The pH of the aqueous emulsion of acrylic polymer in the present disclosure has a pH no higher than 11. Generally, one or more volatile or non-volatile bases can be incorporated in an effective amount to maintain the pH of the composition in the range of from 7.2 to 11 or in the range of from 7.5 to 10.5. In some embodiments, one or more volatile or non-volatile bases can be incorporated in the composition at concentrations of between 0 wt %and 5.0 wt %. In certain embodiments, one or more volatile bases can be incorporated in the composition at concentrations of between 0.1 wt %and 2.5 wt %.

The aqueous emulsion of acrylic polymer may have post added additives for quick drying such as poly-functional amine polymers such as polyethylenimine (PEI) .

The aqueous emulsion of acrylic polymer may have a solids content of 30%-70%, or 40%-65%or 45-60%based on the total weight of the aqueous emulsion of acrylic polymer.

The emulsion of acrylic polymer may be present in an amount of 5%or more, 10%or more, 15%or more, 20%or more, or even 30%or more, and at the same time, 80%or less, 70%or less, 60%or less, 50%or less, 45%or less, by weight based on the total weight of the coating composition.

A multiple-functional composite

The multiple-functional composite are spray-dried composite particles comprising by dry weight based on total dry weight of the spray-dried composite particles, from 60%to 90%, preferably from 65%to 88%, and more preferably from 70%to 85%, inorganic extenders, from 5%to 25%, preferably from 7%to 20%, and more preferably from 10%to 15%, inorganic pigments, and from 3%to 20%, preferably 1%to 10%, more preferably from 2%to 8%, and even more preferably from 3%to 7%, water-insoluble polymer particles.

The inorganic extenders have a particle size of from 0.3 to 30 μm, preferably from 0.5 to 20 μm, and more preferably from 1 to 10 μm.

The spray-dried composite particles have a particle size of from 1 to 100 μm, preferably from 3 to 70 μm, and more preferably from 5 to 40 μm.

The water-insoluble polymer particles comprise, as polymerization units, at least one α, β-ethylenically unsaturated nonionic monomer, that is, α, β-ethylenically unsaturated monomer without bearing an ionic charge between pH=1-14. Suitable examples of the α, β-ethylenically unsaturated nonionic monomers include (meth) acrylic ester monomers, i.e., methacrylic ester or acrylic ester monomers including methyl acrylate, ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, decyl acrylate, lauryl acrylate, methyl methacrylate, butyl methacrylate, isodecyl methacrylate, and lauryl methacrylate; (meth) acrylonitrile; styrene and substituted styrene such as α-methyl styrene, and vinyl toluene; ; vinyl esters such as vinyl acetate, vinyl butyrate, and vinyl versatate; and other vinyl monomers such as vinyl chloride and vinylidene chloride. Preferably, the α, β-ethylenically unsaturated nonionic monomers are ethyl acrylate, methyl methacrylate, 2-hydroxybutyl acrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, vinyl acetate, acrylonitrile, and any combination thereof.

Optionally, the water-insoluble polymer particles further comprise, as polymerization units, from 0.1%to 10%, and preferably from 0.5%to 5%, by dry weight based on total dry weight of the polymer particles, an ethylenically unsaturated monomer carrying at least one functional group selected from carboxyl, carboxylic anhydride, hydroxyl, amide, amino, ureido, acetoacetate, sulphonate, phosphonate, and any combination thereof. Suitable examples of these monomers are ethylenically unsaturated carboxylic or dicarboxylic acid such as acrylic or methacrylic acid, itaconic acid, and maleic acid; ethylenically unsaturated amide such as (meth) acrylamide; ethylenically unsaturated N-alkylolamide such as N-methylol (meth) acrylamide and 2-hydroxyethyl (meth) acrylamide; hydroxyalkyl ester of the carboxylic or dicarboxylic acid, such as hydroxyethyl (meth) acrylate and hydroxypropyl (meth) acrylate; amino-functional monomers such as N, N-dimethylaminoethyl methacrylate; ureido-functional monomers such as methacrylamidoethyl-2-imidazolidinone; monomers bearing acetoacetate-functional groups such as acetoacetoxyethyl methacrylate; and any combination thereof.

The polymerization of the polymer particles can be any methods known in the art, and includes emulsion polymerization and mini-emulsion polymerization.

The inorganic pigment is a particulate inorganic material which is capable of materially contributing to the opacity (i.e., hiding capability) of a composition. Such materials typically have a refractive index of greater than 1.8, and include titanium dioxide (TiO ₂) , zinc oxide, zinc sulfide, barium sulfate, barium carbonate, and lithopone. TiO ₂ is preferred.

The inorganic extender is a particulate inorganic material having a refractive index of less than or equal to 1.8 and greater than 1.3, and including calcium carbonate, clay, calcium sulfate, aluminosilicate, silicate, zeolite, mica, diatomaceous earth, aluminium oxide (Al ₂O ₃) , zinc phosphate, solid or hollow glass, and ceramic bead. Calcium carbonate, clay, mica, and Al ₂O ₃ are preferred. Calcium carbonate is more preferred.

The spray-dried composite particles further comprise less than 3%, preferably less than 2%by dry weight based on total dry weight of the particles, a dispersant. Suitable examples of the dispersant include non-ionic, anionic and cationic dispersants such as polyacid with suitable molecular weight, 2-amino-2-methyl-1-propanol (AMP) , dimethyl amino ethanol (DMAE) , potassium tripolyphosphate (KTPP) , trisodium polyphosphate (TSPP) , citric acid and other carboxylic acids. Preferred dispersants are polyacids, i.e., homopolymers or copolymers of carboxylic acids, hydrophobically or hydrophilically modified polyacids, salts thereof, and any combination thereof. Suitable examples of the hydrophobically or hydrophilically modified polyacids include polyacrylic acid, polymethacrylic acid, and maleic anhydride modified with hydrophilic or hydrophobic monomers such as styrene, acrylate or methacrylate esters, diisobutylene. The molecular weight of such polyacid dispersant is from 400 to 50,000, preferably from 500 to 30,000, more preferably from 1000 to 10,000, and most preferably from 1,500 to 3,000.

The spray-dried composite particles may further comprise less than 3%, preferably less than 2%by dry weight based on total dry weight of the particles, a flow additive. Suitable examples of the flow additive include magnesium stearate, mannitol, stearyl alcohol, glyceryl monostearate, and any combination thereof.

The spray-dried composite particles may further comprise less than 3%, preferably less than 2%by dry weight based on total dry weight of the particles, a defoamer. The defoamer may be any suitable defoamer as known in the art. Suitable examples of the defoamer include siloxane based defoamers and mineral oil based defoamers.

The spry-dried composite particles may further comprise less than 3%, preferably less than 2%by dry weight based on total dry weight of the particles, a thickener. Suitable examples of the thickener include polyvinyl alcohol (PVA) , hydrophobically modified alkali soluble emulsions (HASE) , alkali-soluble or alkali swellable emulsions (ASE) , hydrophobically modified ethylene oxide-urethane polymers known in the art as HEUR, cellulosic thickeners such as hydroxymethyl cellulose (HMC) , hydroxyethyl cellulose (HEC) , hydrophobically-modified hydroxy ethyl cellulose (HMHEC) , sodium carboxymethyl cellulose (SCMC) , sodium carboxymethyl 2-hydroxyethyl cellulose, 2-hydroxypropyl methyl cellulose, 2-hydroxyethyl methyl cellulose, 2-hydroxybutyl methyl cellulose, 2-hydroxyethyl ethyl cellulose, and 2-hydoxypropyl cellulose.

The spray-dried composite particles contain less than 2%, preferably less than 0.5%, and more preferably less than 0.1%, by weight based on total weight of the particles, water.

The spray-drying process for preparation of the spray-dried composite particles comprises the steps of: (a) preparing a slurry for spray-drying comprising by dry weight based on total dry weight of the slurry, from 60%to 90%of inorganic extenders, from 5%to 25%of inorganic pigments, and from 3%to 20%of water-insoluble polymer particles; and (b) adding the slurry into a spray dryer and preparing the spray-dried composite particles.

The spray-drying method involves the conversion of a slurry droplet into dried powders by evaporation of the solvent/water in a one-step process through a spray dryer. It is well-known in the art that the desired particle morphologies and size distribution are achieved by controlled solids content of the slurry, nozzle diameter, air inlet or air outlet temperature, pump speed, and air pressure of the spray dryer. In this disclosure, inorganic pigments, inorganic extenders and water-insoluble polymer particles are mixed with by weight based on total weight of the slurry, from 20%to 99%water, and the dispersant, the defoamer, and the optional flow additive to form the slurry. The slurry may be added into any commercially available spray dryer, such as Mini Spray Dryer B-290 from BUCHI Corporation, and GEA Niro Spray Dryer from GEA Process Engineering Inc. to prepare the desired spray-dried composite particles of the present disclosure.

The multiple-functional composite may be present in an amount of 1%or more, 2%or more, 5%or more, 10%or more, or 11%or more, 15%or more, or even 20%or more, and at the same time, 40%or less, 30%or less, 25%or less, or even 20%or less, by weight based on the total weight of the coating composition.

Pigments

The coating composition of the present disclosure may also comprise one or more pigments. Pigments may include particulate inorganic materials which are capable of materially contributing to the opacity or hiding capability of a coating. Such materials typically have a refractive index greater than 1.8. Examples of suitable pigments include titanium dioxide (TiO ₂) , zinc oxide, zinc sulfide, iron oxide, barium sulfate, barium carbonate, or mixtures thereof. The pigments may be present in an amount of zero or more, 0.5 %or more, 1%or more, 1.5%or more, or even 2%or more, and at the same time, 20%or less, 15%or less, 10%or less, or even 5%or less, by weight based on the total weight of the coating composition.

Extenders

The coating composition of the present disclosure may comprise one or more extenders. Extenders may include particulate inorganic materials typically having a refractive index of less than or equal to 1.8 and greater than 1.5. Examples of suitable extenders include calcium carbonate, silica, aluminum oxide (Al ₂O ₃) , clay, calcium sulfate, aluminosilicate, silicate, zeolite, mica, sand, diatomaceous earth, solid or hollow glass, ceramic bead, and opaque polymers such as ROPAQUE ^TM Ultra E available from The Dow Chemical Company (ROPAQUE is a trademark of The Dow Chemical Company) , or mixtures thereof. The extenders may be present in an amount of zero or more, 5%or more, 10%or more, 15%or more or even 20 %or more, and at the same time, 80%or less, 70%or less, 60%or less, 50%or less, 40%or less, 30%or less, or even 25%or less, by weight based on the total weight of the coating composition.

Thickeners

The coating composition of the present disclosure may comprise one or more thickener (also known as “rheology modifier” ) . Thickeners may include polyvinyl alcohol (PVA) , clay materials, acid derivatives, acid copolymers, urethane associate thickeners (UAT) , polyether urea polyurethanes (PEUPU) , polyether polyurethanes (PEPU) , or mixtures thereof. Examples of suitable thickeners include alkali swellable emulsions (ASE) such as sodium or ammonium neutralized acrylic acid polymers; hydrophobically modified alkali swellable emulsions (HASE) such as hydrophobically modified acrylic acid copolymers; associative thickeners such as hydrophobically modified ethoxylated urethanes (HEUR) ; and cellulosic thickeners such as methyl cellulose ethers, hydroxymethyl cellulose (HMC) , hydroxyethyl cellulose (HEC) , hydrophobically-modified hydroxy ethyl cellulose (HMHEC) , sodium carboxymethyl cellulose (SCMC) , sodium carboxymethyl 2-hydroxyethyl cellulose, 2-hydroxypropyl methyl cellulose, 2-hydroxyethyl methyl cellulose, 2-hydroxybutyl methyl cellulose, 2-hydroxyethyl ethyl cellulose, and 2-hydoxypropyl cellulose. Preferred thickener is based on HEUR. The thickener may be present in an amount of zero or more, 0.01%or more, or even 0.1%or more, and at the same time, 5%or less, 4%or less, or even 3%or less, by weight based on the total weight of the coating composition.

Defoamers

The coating composition of the present disclosure may comprise one or more defoamer. “Defoamer” herein refers to a chemical additive that reduces and hinders the formation of foam. Defoamers may be silicone-based defoamers, mineral oil-based defoamers, ethylene oxide/propylene oxide-based defoamers, alkyl polyacrylates, or mixtures thereof. Suitable commercially available defoamers include, for example, TEGO Airex 902 W and TEGO Foamex 1488 polyether siloxane copolymer emulsions both available from TEGO, BYK-024 silicone defoamer available from BYK, NOPCO NXZ defoamer available from NOPCO or mixtures thereof. The defoamer may be present in an amount of zero or more, 0.01%or more, or even 0.1%or more, and at the same time, 2%or less, 1.5%or less, or even 1%or less, by weight based on the total weight of the coating composition.

Dispersants

The coating composition of the present disclosure may further comprise one or more dispersants. Suitable examples of the dispersant include non-ionic, anionic and cationic dispersants such as polyacid with suitable molecular weight, 2-amino-2-methyl-1-propanol (AMP) , dimethyl amino ethanol (DMAE) , potassium tripolyphosphate (KTPP) , trisodium polyphosphate (TSPP) , citric acid and other carboxylic acids. Preferred dispersants are polyacids, i.e., homopolymers or copolymers of carboxylic acids, hydrophobically or hydrophilically modified polyacids, salts thereof, and any combination thereof. Suitable examples of the hydrophobically or hydrophilically modified polyacids include polyacrylic acid, polymethacrylic acid, and maleic anhydride modified with hydrophilic or hydrophobic monomers such as styrene, acrylate or methacrylate esters, diisobutylene. The molecular weight of such polyacid dispersant is from 400 to 50,000, preferably from 500 to 30,000, more preferably from 1000 to 10,000, and most preferably from 1,500 to 3,000. The dispersant may be present in an amount of zero or more, 0.1%or more, 0.2%or more, or even 0.3 %or more, and at the same time, 12%or less, 10%or less, 9%or less, 5%or less, or even 2%or less, by weight based on the total weight of the coating composition.

Coalescents

The coating composition of the present disclosure may comprise one or more coalescent. “Coalescent” herein refer to a slow-evaporating solvent that facilitates diffusion of polymer particles into a continuous film under ambient condition. Suitable coalescents may include, for example, 2-n-butoxyethanol, dipropylene glycol n-butyl ether, propylene glycol n-butyl ether, dipropylene glycol methyl ether, propylene glycol methyl ether, propylene glycol n-propyl ether, diethylene glycol monobutyl ether, ethylene glycol monobutyl ether, ethylene glycol monohexyl ether, triethylene glycol monobutyl ether, dipropylene glycol n-propyl ether, n-butyl ether, or mixtures thereof. Preferred coalescents include dipropylene glycol n-butyl ether, ethylene glycol monobutyl ether, diethylene glycol monobutyl ether, n-butyl ether, or mixtures thereof. The coalescent may be present in an amount of zero or more, 0.1%or more, or even 1%or more, and at the same time, 12%or less, 10%or less, or even 9%or less, by weight based on the total weight of the coating composition.

Cementitious materials

The coating composition of the present disclosure, especially the two-component cementitious waterproofing coating composition may comprise one or more cementitious materials such as cement. Preferably, the cement can be selected from white cement, silicate cement and composite silicate cement. The cementitious materials can be present in an amount of zero or more, 5%or more, 10%or more, or even 15%or more, and at the same time, 50%or less, 40%or less, 30%or less, or even 25%or less, by weight based on the total weight of the coating composition.

Other additives

In addition to the components described above, the coating composition of the present disclosure may further comprise any one or combination of the following additives: buffers, neutralizers, humectants, mildewcides, biocides, wetting agents, colorants, flowing agents, anti-oxidants, plasticizers, leveling agents, thixotropic agents, adhesion promoters, water retention additives and grind vehicles. When present, these additives may be present in a combined amount of from 0 to 5%by weight or from 0.1%to 3%by weight, or from 0.5 to 1.5%by weight, based on the total weight of the coating composition.

Preferably, the coating composition is selected from an elastomeric roof coating composition, an elastomeric wall coating composition, a two-component cementitious waterproofing coating composition and a stucco coating.

The elastomeric roof coating composition or an elastomeric wall coating composition

The elastomeric roof coating composition or an elastomeric wall coating composition comprises:

i) an aqueous emulsion of acrylic polymer; and

ii) a multiple-functional composite;

wherein the multiple-functional composite is spray-dried composite particles comprising by dry weight based on total dry weight of the spray-dried composite particles, from 60%to 90%of inorganic extenders, from 5%to 25%of inorganic pigments, and from 3%to 20%of water-insoluble polymer particles;

Preferably, the multiple-functional composite is used in an amount of 12%or more, or 15%or more, 20%or more, or 25%or more, or even 30%or more, and at the same time, 70%or less, 60%or less, 50%or less, 45%or less, 40%or less, by weight based on the total weight of the coating composition.

Preferably, the elastomeric roof coating composition or an elastomeric wall composition further comprises one or more components selected from the group consisting of pigments, extenders, defoamers, dispersants, thickeners, and coalescents.

The two-component cementitious waterproofing coating composition

The two-component cementitious waterproofing coating composition comprises:

A) a liquid part comprising an aqueous emulsion of acrylic polymer;

B) a powder part comprising

B1) a cementitious material, and

B2) a multiple-functional composite;

Preferably, the aqueous emulsion of acrylic polymer is used in an amount of 30%or more, 40%or more, 45%or more, 50%or more, 60%or more, and 90%or less, 85%or less, 80%or less, 75%or less, by weight based on the total weight of the liquid part.

Preferably, the cementitious material is used in an amount of 10%or more, 15%or more, 20%or more, 25%or more, 28%or more, and 50%or less, 40%or less, 45%or less, 40%or less, by weight based on the total weight of the powder part. The cementitious material can be for example, cement. The cement can be selected from white cement, silicate cement and composite silicate cement.

Preferably, the multiple-functional composite is used in an amount of 2%or more, 3%or more, 5%or more, 10%or more, 15%or more, 20%or more, 25%or more, and 50%or less, 40%or less, 45%or less, 40%or less, 35%or less, 30%or less, by weight based on the total weight of the powder part.

Preferably, the powder part further comprises B3) one or more extenders. The extenders can be selected from calcium carbonate, silica sand or a mixture thereof. Preferably, the extender may be used in an amount of 10%or more, 15%or more, 20%or more, 25%or more, 30%or more, and 80%or less, 70%or less, 60%or less, 50%or less, 40%or less, by weight based on the total weight of the powder part.

Preferably, the powder part further comprises calcium carbonate. Preferably, calcium carbonate may be used in an amount of 5%or more, 10%or more, 12%or more, and 40%or less, 30%or less, 20%or less, by weight based on the total weight of the powder part.

Preferably, the powder part further comprises silica sand. Preferably, the silica sand may be used in an amount of 5%or more, 10%or more, 20%or more, 30%or more, and 80%or less, 70%or less, 60%or less, 50%or less, by weight based on the total weight of the powder part.

The liquid part may further comprise defoamers, dispersants as described herein above.

The weight ratio between the liquid part to the powder part is from 1: 10 to 10: 1, preferably from 1: 5 to 5: 1, more preferably from 1: 2.5 to 2.5: 1.

Preferably, the two-component cementitious waterproofing coating composition further comprises one or more components selected from the group consisting of pigments, extenders, defoamers, dispersants, thickeners, and coalescents.

The stucco coating composition

The stucco coating composition comprises:

i) an aqueous emulsion of acrylic polymer;

ii) a multiple-functional composite; and

iii) a silica sand;

Preferably, the aqueous emulsion of acrylic polymer may be used in an amount of 5%or more, 10%or more, 12%or more, 15%or more, or even 20%or more, and at the same time, 60%or less, 50%or less, 40%or less, 35%or less, 30%or less, by weight based on the total weight of the coating composition.

Preferably, the silica sand may be used in an amount of 10%or more, 15%or more, 20%or more, 25%or more, 30%or more, 40%or more, and 80%or less, 70%or less, 60%or less, 50%or less, by weight based on the total weight of the coating composition.

Preferably, the multiple-functional composite may be used in an amount of 2%or more, 3%or more, 5%or more, 10%or more, 15%or more, 20%or more, 25%or more, and 80%or less, 70%or less, 60%or less, 50%or less, 40%or less, 45%or less, 40%or less, 35%or less, 30%or less, by weight based on the total weight of the coating composition.

Preferably, the stucco coating composition further comprises one or more components selected from the group consisting of pigments, other extenders, defoamers, dispersants, thickeners, and coalescents.

PREPARATION METHOD

The coating composition of the present disclosure may be prepared with techniques known in the coating art, for example, by admixing the aqueous emulsion of acrylic polymer with other optional components described above. Components in the coating composition may be mixed in a suitable order to provide the coating composition of the present disclosure. Any of the above-mentioned optional components may also be added to the composition during or prior to the mixing to form the coating composition. The coating composition of the present disclosure is typically an aqueous coating composition.

The present disclosure also provides a method of preparing a coating. The method may comprise: forming the coating composition, applying the coating composition to a substrate, and drying, or allowing to dry, the applied coating composition to form the coating. The coating composition can be applied to a substrate by incumbent means including brushing, dipping, rolling and spraying. The coating composition is preferably applied by rolling and spraying. Typical rollers and standard rolling techniques are used. The standard spray techniques and equipment for spraying such as air-atomized spray, air spray, airless spray, high volume low pressure spray, and electrostatic spray such as electrostatic bell application, and either manual or automatic methods can be used. After the coating composition has been applied to a substrate, the coating composition can dry, or allow to dry, to form a film (this is, coating) at room temperature (20-25 ℃) , or at an elevated temperature, for example, from 35 to 60 ℃. The coating composition can provide the coating obtained therefrom (that is, the film obtained after drying, or allowing to dry, the coating composition applied to a substrate) .

The coating composition of the present disclosure can be applied to, and adhered to, various substrates. Examples of suitable substrates include concrete, cementitious substrates, woods, metals, stones, elastomeric substrates, glass or fabrics. The coating composition is suitable for various coating applications, such as waterproofing coatings, architecture coatings, marine and protective coatings, automotive coatings, wood coatings including furniture coatings, joinery coatings, and floor coatings, coil coatings, traffic paints, and civil engineering coatings. The coating composition can be used alone, or in combination with other coatings to form multi-layer coatings.

EXAMPLES

Some embodiments of the invention will now be described in the following examples, wherein all parts and percentages are by weight unless otherwise specified.

A. The preparation of multiple-functional composite (MFC) (Example A)

1. Preparation of spry-dried MFC:

A slurry was prepared by mixing 0.8 g Orotan ^TM 1288 (a dispersant, available from The Dow Chemical Company) , 0.2 g AMP-95 (a base, available from Angus Chemical Company) and 28 g DI water at low speed mixer. 22.2 g R-996 TiO ₂ (available from Chemours) was mixed with the slurry at increased 1500 rpm shear speed for 30 minutes. 168 g commercial CC700 Calcium Carbonate slurry (available from Guangfu Building Materials Company) and 9 g EVOQUE ^TM 1200 emulsion (45%solid, available from The Dow Chemical Company) were then added at around 700 rpm and mixed for 10 minutes. Additional water was further added to the slurry to keep the solid content of the slurry at 50%.

The prepared slurry was added into the Mini Spray Dryer B-290 available from BUCFFLL Corporation and the device was set as below parameters: the nozzle diameter equals to 1 mm, the temperature of air inlet equals to 120 ℃, the temperature of air outlet equals to 100 ℃, the pump speed equals to 0.45 L per hour, and the air pressure equals to about 196 KPa. The spray dried multiple-functional composite (MFC) particles with a particle size of 10-50 um were collected from the product collection vessel of the spray dryer.

The obtained MFC particles were used in the preparation of the following coating compositions.

B. The preparation of coating compositions

I. ERC formulations

The information of the raw materials used in the formulations is listed in the following Table:

*Primal ^TM EC-1791 is a 55%solids all-acrylic latex polymer where the major components are derived from monomers of BA and MMA. The latex pH = 9.2, and the polymer Tg = -40 ℃.

**Primal ^TM EC-1791QS is a quick-set version of the EC-1791 acrylic latex. EC-1791QS is an all-acrylic latex polymer where the major components are derived from monomers of BA and MMA. EC-1791QS contains a polyfunctional amine polymer to reduce the set time. The latex is pH 10.5, 51%solids, and the polymer Tg is -40 ℃.

[BA: Butyl Acrylate; MMA: Methyl Methacrylate]

i) Preparation method of the ERC formulations:

The inventive formulations and comparative formulations were prepared according to the below method:

1. During GRIND process, the initial ingredient (A) of the GRIND was charged to the mixing kettle. KTPP (Potassium triphosphate) was added before any latex emulsion was charged into the kettle.

2. While mixing at low speed (300-400 rpm) , the ingredient (B) pigment, extender and multiple-functional composite, if present, were added to the kettle.

3. After all the ingredients (B) were added to the kettle, the mixer was stopped and the sides and bottom of the kettle were scraped.

4. The mixer was turned back on and the mixture was ground at high speed (600-800 rpm) for 15-30 minutes, or until a good grind was obtained (Hegman reading of 4.5 to 5.0) .

5. For the LETDOWN process, the latex emulsion in ingredient (C) was added to the kettle. The defoamer was added on top of the emulsion.

6. The mixer was turned on and this mixture was blended together.

7. While blending, ingredients (D) and (E) were added to the kettle.

8. Ingredient F, as a premix, was added immediately after the NH ₄OH had been added to the mixture.

Table 1 Ingredients Details of Inventive Example 1-4 and Comparative Example 1

Table 2 Ingredients Details of Comparative Example 2 and Inventive Example 4

ii) Test method

The key properties of above formulation examples were evaluated in accordance to below GB standards and requirements.

Coating Film Drying Time (GB 1728-1979 Testing Methods for the Drying Time of Coating Films and Skim Coat) :

Coating films were liquid applied by 1000 um thickness applicator on top of standard experimental fiber cement panels. Below testing methods were adopted to test the surface drying time (touch dry) and full drying time within the area range at least 1 cm aside from the coating film edge.

Surface drying time (touch dry) : Carefully touch the coating surface using fingers. If it feels tacky for coating film but no coating left on fingers, it is considered as touch dry. Record the time as the surface drying time.

Full drying time: Use knife to cut through the coating film to carefully observe the bottom and inside section of coating film. If there is no tacky phenomenon, it is considered as full dry. Record the time as the full drying time.

Tensile Strength and Elongation at Break (according to JG/T 375-2012 Acrylic waterproof coating for metal roof) :

a) Draw-down a coating film on a release paper (dry film thickness is 1mm) ;

b) Cure for 4 days in a controlled temperature room (Temperature: 23 ℃, humidity: 50%) ; then place in 40 ℃ oven for 2 days;

c) Cut coating films into a dumb bell shape;

d) Use Universal Testing Machine (i.e. Gotech-AI 7000M) with a crosshead speed of 200 mm/min to record elongation and tensile at room temperature.

Water Absorption

1) Measure cured coating film weight as m ₁;

2) Immerse above coating films into qualified water in GB/T 6682-2008 for 168 hrs;

3) Absorb water on coating film and weigh as m ₂;

4) Calculate water absorption ratio as

Table 3 Performance Results of EC1791 with MFC (ERC Formulations)

Primal ^TM EC1791 was used as a control formulation as comparative example 1. Multiple functional composites (MFC) were post-added into ERC formulations, as replacement for part of CaCO ₃ and TiO ₂. Varied dosage amount of MFC (11.6%and 15.2%, based on the total weight of the coating composition) was used. During ERC formulation process, it was also observed that MFC had the functionality of thickening effect on formulation.

Regarding surface drying time, it seemed 11.6%of MFC had nearly no effect on coating surface drying. When MFC content was increased to 15.2%, the surface drying time was improved from 100 minutes to 95 minutes. 50%dosage of HEC thickener had similar effect as Inventive Example 1.

Regarding full drying time, 11.6%of MFC already reduced drying time from 130 minutes to 115 minutes. When the content of MFC was increased to 15.2%, the coating film full drying time was reduced to 105 minutes, which was nearly 20%faster.

Tensile strength and elongation property kept similar performance range after MFC was used as the functional extenders in ERC formulation compared with comparative example 1. Typical tensile strength was in the range of 2.1-2.6 MPa while elongation was in the range of 154-186%which could both pass the JG/T375 requirements (Tensile strength>1.5 MPa while elongation>150%) .

After post-adding MFC in ERC formulation, water absorption ratio for dry coating films can still meet JG/T 375 requirement (water absorption <15%after 7 days) .

Table 4 Performance Results of EC1791QS with MFC ERC Formulations

ERC coating compositions were prepared according Table 2. The general performance results were summarized in Table 4. Typical ERC coatings’ film thickness was about 1.0-1.2 mm.

There was almost no difference for EC1791QS compared with EC1791 formulation regarding surface drying time or coating film full drying time. 15.2%of MFC reduced both surface drying time and full drying time which proved effective fast-drying functionality of MFC in ERC formulations.

Tensile strength of EC1791QS was higher than EC1791 while elongation was a bit lower. After post-adding 15.2%of MFC in place of part of CaCO ₃, there was no big influence on mechanical properties.

The water absorption of Inventive Example 4 passed JG/T 375 ERC code requirements.

II: 2K (two-component) cementitious waterproofing formulations

The information of the raw materials used in the 2K cementitious waterproofing formulations is listed in the following Table:

*Latex Tianba ^TM 2012*is 56%solids styrene acrylic latex polymer where the major components are derived from monomer of BA and St. The polymer Tg = -11 ℃

[BA: Butyl Acrylate; St: Styrene]

i) Method for preparing 2K cementitious waterproofing coatings:

Liquid versus powder ratio was 1: 2.3 which was in typical range of JS type III.

For liquid part formulation, all the ingredients could be added based on formulation design sequence. Orotan ^TM 1850E was post-added into control emulsion (i.e. Tianba ^TM 2012) for better dispensability of cement/silica/CaCO ₃ which could improve workability and influence the mechanical property of well-cured membranes. 0.3%defoamer was added into liquid part to eliminate foam caused during stirring process because foam may have much negative influence on mechanical properties.

For powder part formulation, the dry powder ingredients were mixed together with proper dispending.

To prepare 2K cementitious waterproofing coating, the powder part formulation would be added into liquid part formulation according to current mixing ratio under lower speed 300-400 rpm) . The mixed slurry was dispensed for 5 minutes under 600-800 rpm then the dispensing was stopped for 1-3 minutes for defoaming. The slurry would be dispensed again for 3 minutes before further application on jobsites or for further performance validation.

Table 5 Formulation Ingredients for 2K Cementitious Waterproofing Coatings

Table 6 Performance Results for 2K Cementitious Waterproofing Coatings

MFC was also formulated into two-component cementitious waterproofing coatings to replace part of CaCO ₃ in powder part formulation. The formulation ingredients could be found in Table 5 and performance results were shown in Table 6. Typical 2K cementitious waterproofing coatings’ film thickness was about 1.2-1.5mm.

Full drying time for both Inventive Example 5 and Inventive Example 6 were reduced from 90 minutes to 65 minutes and 60 minutes which were significant fast-drying functionality.

III: Stucco coating formulations

The information of the raw materials used in the stucco coating formulations is listed in the following Table:

*Primal ^TM AC-261P is 50%solids all acrylic latex polymer where the major components are derived from monomer of BA and MMA. The latex has a pH of 8.8 and a Tg of 23 ℃.

[BA: Butyl Acrylate; MMA: Methyl Methacrylate]

Method for preparing the stucco coating composition:

The stucco coating composition was prepared in according to the formulation designed sequence. The acrylic latex was added as the first ingredient in the stucco formulation. The wetting agent and defoamer were used for better system stability and de-bubbling. Dispersant was used to better dispense the pigment and extenders. HEC type thickener 250HBR was used as the rheology modifier for improving system stability. Pigments and extenders including TiO ₂, MFC, CaCO ₃ and silica sand were added gradually with relatively higher dispensing speed. The stucco coating composition was mixed well and uniformly for further applications.

Table 7 Formulation Ingredients of Stucco Coating Compositions

	Comparative Example 4	Inventive Example 7
Primal ^TM AC-261P	70.4	70.4
ECOSURF ^TM BD-405	2.16	2.16
Nopco NXZ	0.4	0.4
Orotan ^TM 1128	2.4	2.4
Natrosol 250HBR	0.4

Water	2.8	2.8
Texanol	3.4	3.4
TiO ₂ R960	16.12
Calcium carbonate 500 mesh	60.44
Calcium carbonate 200 mesh	104.8	104.8
MFC		76.56
Silica sand #40-70 mesh	90.68	90.68
Silica sand #20-40 mesh	40.32	40.32
Total	～400	～400

Table 8 Performance Results of Stucco Coatings

	Comparative Example 4	Inventive Example 7
Viscosity, cP, Brookfield 7#, 30 rpm	16000	20500
Surface drying time of one layer, 1mm	40 min	20 min

Moreover, MFC was also formulated into stucco coating compositions. Formulation ingredients were shown in Table 7 while the thickening viscosity and surface drying time were listed in Table 8. Typical stucco coatings’ film thickness was about 1.0-1.2 mm.

The surface drying time of stucco coating was significantly reduced from 40 minutes to 20 minutes. At the same time, post-adding MFC without HEC thickening could get even higher thickening efficiency over comparative example 4.

As shown in Figure 1, comparative example 4 (on the right) and Inventive Example 7 (on the left) were applied on top of concrete substrate. Two coating films were cured at standard condition (23 ℃ temperature, 50%humidity) for one hour. Early water spray evaluation was carried out and result was recorded in Figure 1. Comparative example 4’s coating film were flushed away with visible base coat while Inventive example 7 still had good film formation which demonstrated MFC’s fast drying in stucco film curing.

Claims

A method of reducing the drying time of a coating composition, comprising adding a multiple-functional composite to the coating composition,

wherein the multiple-functional composite is spray-dried composite particles comprising by dry weight based on total dry weight of the spray-dried composite particles, from 60%to 90%of inorganic extenders, from 5%to 25%of inorganic pigments, and from 3%to 20%of water-insoluble polymer particles; and

wherein the coating composition comprises an aqueous emulsion of acrylic polymer.
The method of claim 1, wherein the acrylic polymer has at least one structural unit of one or more ethylenically unsaturated monomers carrying at least one heterofunctional group.
The method of claim 1, wherein the coating composition is selected from the group consisting of an elastomeric roof coating composition, an elastomeric wall coating composition, a two-component cementitious waterproofing coating composition, and a stucco coating composition.
A use of a multiple-functional composite in reducing the drying time of a coating composition, wherein the multiple-functional composite is spray-dried composite particles comprising by dry weight based on total dry weight of the spray-dried composite particles, from 60%to 90%of inorganic extenders, from 5%to 25%of inorganic pigments, and from 3%to 20%of water-insoluble polymer particles;

wherein the coating composition comprises:

(a) an aqueous emulsion of acrylic polymer; and

(b) the multiple-functional composite.
The use of claim 4, wherein the acrylic polymer has at least one structural unit of one or more ethylenically unsaturated monomers carrying at least one heterofunctional group.
The use of claim 4, wherein the coating composition is selected from the group consisting of an elastomeric roof coating composition, an elastomeric wall coating composition, a two-component cementitious waterproofing coating composition, and a stucco coating composition.
An elastomeric roof coating composition or an elastomeric wall coating composition comprising:

i) an aqueous emulsion of acrylic polymer; and

ii) a multiple-functional composite;

wherein the multiple-functional composite is spray-dried composite particles comprising by dry weight based on total dry weight of the spray-dried composite particles, from 60%to 90%of inorganic extenders, from 5%to 25%of inorganic pigments, and from 3%to 20%of water-insoluble polymer particles; and

wherein the multiple-functional composite is used in an amount of 11%or more by weight based on the total weight of the coating composition.
The coating composition of claim 7, wherein the multiple-functional composite is used in an amount of 12%or more and at the same time 70%or less by weight based on the total weight of the coating composition.
A two-component cementitious waterproofing coating composition comprising:

A) a liquid part comprising an aqueous emulsion of acrylic polymer;

B) a powder part comprising

B1) a cementitious material, and

B2) a multiple-functional composite;

wherein the multiple-functional composite is spray-dried composite particles comprising by dry weight based on total dry weight of the spray-dried composite particles, from 60%to 90%of inorganic extenders, from 5%to 25%of inorganic pigments, and from 3%to 20%of water-insoluble polymer particles.
The coating composition of claim 9, wherein the cementitious material is used in an amount of 10%or more and 50%or less by weight based on the total weight of the powder part.
The coating composition of claim 9, wherein the multiple-functional composite is used in an amount of 2%or more and 50%or less by weight based on the total weight of the powder part.
The coating composition of claim 9, wherein the weight ratio between the liquid part to the powder part is from 1: 10 to 10: 1.
A stucco coating composition comprises:

i) an aqueous emulsion of acrylic polymer;

ii) a multiple-functional composite; and

iii) a silica sand;

wherein the multiple-functional composite is spray-dried composite particles comprising by dry weight based on total dry weight of the spray-dried composite particles, from 60%to 90%of inorganic extenders, from 5%to 25%of inorganic pigments, and from 3%to 20%of water-insoluble polymer particles.
The coating composition of claim 13, wherein the silica sand is used in an amount of 10%or more and 80%or less by weight based on the total weight of the coating composition.
The coating composition of claim 13, wherein the multiple-functional composite is used in an amount of 2%or more and 80%or less by weight based on the total weight of the coating composition.