KR100586125B1 - Polymers derived from isobutylene and fluoro monomer - Google Patents

Abstract

The present invention relates to a composition comprising a fluorine-containing copolymer containing at least 30 mole% residues having alternating structural units of formula (I):

Formula 1

-[DM-AM]-

Where

DM is a residue from a donor monomer of Formula I:

AM stands for receptor monomer:

Formula I

here,

R ¹ is linear or branched C ₁ -C ₄ alkyl;

R ² is selected from methyl, linear, cyclic or branched C ₁ -C ₂₀ alkyl, alkenyl, aryl, alkaryl, and aralkyl.

The copolymer contains at least 5 weight percent fluorine. The composition may comprise a co-reactive functional group and may be a thermosetting composition that may be used to coat the substrate. The thermosetting composition may be part of a multicomponent composite coating comprising a coating film deposited from a colored film-forming composition and a substantially pigment free coating film applied to at least a portion of the coating film.

Description

POLYMERS DERIVED FROM ISOBUTYLENE AND FLUORO MONOMER} Polymers derived from isobutylene and fluoro monomers             

The present invention relates generally to fluoropolymers and thermosetting compositions containing fluoropolymers. More specifically, the present invention relates to fluoropolymers containing functional groups and thermosetting compositions containing functional fluoropolymers.

Coatings derived from compositions containing fluoropolymers typically provide good chemical resistance, weather resistance and heat resistance. Because of these properties, interest in the use of fluoropolymer-based paints is increasing in various fields. For example, fluoropolymer-containing paints have been used as weather resistant painters in the construction, automotive, and chemical industries. Fluoropolymers used in such paints typically include fluorocarbon monomers such as chlorotrifluoroethylene, tetrafluoroethylene or vinylidene fluoride, and other monomers such as vinyl esters or vinyl ethers. And they are generally added to increase the solubility of the resulting fluoropolymers.

For example, US Pat. No. 4,345,057 to Yamabe et al. Discloses fluoropolymers with improved curability. Coatings using fluoropolymers reportedly have a shiny finish, good chemical resistance, and good weather resistance. In addition, Japanese Patent No. 04 004246 discloses (A) 30 to 60 mol% of fluoroolefin monomers, (B) 20 to 50 mol% of β, β-substituted olefins, and (C) 1 to 50 mol% Fluorine-containing random copolymers containing monomers containing hydrolyzable silyl groups are disclosed. British Patent 1,121,614 discloses random copolymers derived from tetrafluoroethylene and essentially a 50:50 molar mixture of isobutylene and second olefinic monomers. British Patent No. 1,213,171 discloses random copolymers containing 53 to 67 wt% tetrafluoroethylene, 32 to 44 wt% isobutylene and 0 to 14 wt% additional copolymerizable monomers. US Pat. No. 3,380,974 to Stilmar discloses random copolymers of tetrafluoroethylene, isobutylene and ethylenically unsaturated acid or acid derivatives. US Pat. No. 2,468,664 to Hanford et al. Discloses random copolymers containing 55-80% of tetrafluoroethylene and isobutylene.

In many cases, the durability of the coatings, for example their weather resistance and / or chemical resistance, will depend on the attainment of an optimal balance of physical properties, for example hardness and flexibility of the coating film. In general, achieving this optimal balance is a difficult goal to define.

In addition, the use of fluoropolymer-containing coating compositions has been limited due to the high cost of such coatings, in part due to the cost of fluorocarbon monomers.

Functional fluoropolymers are typically random copolymers comprising functional group-containing acrylic and / or methacrylic monomers. Such functional fluoropolymers will contain a mixture of polymer molecules with varying individual functional group weights and polymer chain structures. In such copolymers, the functional groups are arranged irregularly along the polymer chain. In addition, the number of functional groups is not evenly divided along the polymer molecule, so some polymer molecules may be substantially free of functionality.

In thermosetting compositions, the formation of a three-dimensional crosslinked network depends on the structure and the weight per functional group of the individual polymer molecules contained therein. Polymer molecules with little or no reactive functional groups (or with functional groups not participating in the crosslinking reaction due to their position in the polymer chain) will contribute little or no to the formation of three-dimensional crosslinked networks, and consequently The physical properties of the thermosetting coating formed will be less than optimal and the crosslink density will be reduced.

It would be desirable to provide a fluoropolymer based on a thermosetting composition that is inexpensive and has a predictable polymer structure and provides an optimal balance of film hardness and flexibility in a rigid coating.

Summary of the Invention

The present invention relates to a composition comprising a fluorine-containing copolymer containing at least 30 mole% residues having alternating structural units of formula (I):

-[DM-AM]-

Where

DM is a residue from a donor monomer of Formula I:

AM stands for receptor monomer.

here,

R ¹ is linear or branched C ₁ -C ₄ alkyl;

R ² is selected from methyl, linear, cyclic or branched C ₁ -C ₂₀ alkyl, alkenyl, aryl, alkaryl, and aralkyl.

The copolymer contains at least 5 weight percent fluorine.

The invention also relates to a composition comprising the aforementioned copolymer as a composition containing a co-reactive functional group. Non-limiting examples of such compositions are thermosetting compositions. The invention also relates to a substrate on which at least a portion of the substrate is coated with a thermosetting composition.

The invention further relates to thermosetting compositions comprising the aforementioned copolymers containing reactive functional groups and at least one other component containing functional groups reactive with the functional groups of such copolymers. The invention further relates to a substrate on which at least a portion of the substrate is coated with a thermosetting composition.

The present invention further relates to a multicomponent composite coating composition comprising a top coat film still deposited from a colored film-forming composition and a top coat film that is applied to at least a portion of the film. The undercoat and / or the topcoat comprise one of the thermosetting compositions described above. The invention also relates to a substrate wherein at least a portion of the substrate is coated with the multicomponent composite coating composition.

In addition to the working examples, or unless otherwise indicated, all numbers or expressions representing the amounts of ingredients, reaction conditions, and the like used in the specification and claims are to be understood as being changed in all instances by the term "about." . Various numerical ranges are disclosed herein. Since these ranges are continuous, they include all values between the minimum and maximum values. Unless expressly indicated otherwise, the various numerical ranges specified herein are approximations.

As used herein, the term “copolymer composition” is meant to include not only the synthesized copolymer, but also other components that participate in the synthesis of residues, catalysts and copolymers from the initiator but are not incorporated into the copolymer by covalent bonds. Such residues and other components, which are considered as part of the copolymer composition, are typically mixed or mixed with the copolymer such that they tend to remain with the copolymer when changing containers, changing solvents or changing the dispersion medium. have.

As used herein, the term "substantially free" means that a particular substance is present as an incidental impurity. In other words, this material is not intentionally added to the indicated composition, but may be present in small or trace amounts because it is transferred as an impurity as part of the intended composition component.

The terms "donor monomer" and "receptor monomer" are used throughout this application. In the context of the present invention, the term "donor monomer" refers to a monolayer having a polymerizable ethylenically unsaturated group having a relatively high electron density at the ethylenic double bond, and the term "receptor monomer" has a relatively low electron density at the ethylenic double bond. The monomer which has a polymerizable ethylenically unsaturated group which has is mentioned. This concept has been quantified to some extent by the Alfred-Price Qe scheme (Robert Z. Greenley, Polymer Handbook , 4th edition, Brandrup, Immergut and Gulke, Wiley & Sons, New York, NY, pp. 309-). 319 (1999). All e values cited herein are those described in the Polymer Handbook unless otherwise indicated.

In the Q-e scheme, Q reflects the reactivity of the monomers, and e represents the polarity of the monomer, which represents the electron density of the polymerizable ethylenically unsaturated groups of the given monomer. A positive value of e indicates that the monomer is a acceptor monomer with a relatively low electron density as in the case of maleic anhydride with an e value of 3.69. A low or negative value of e indicates that the monomer is a donor monomer with a relatively high electron density as in the case of vinyl ethyl ether with an e value of -1.80.

As mentioned herein, a strong receptor monomer is meant to include monomers having e values greater than 2.0. The term "warmed receptor monomer" is meant to include monomers having e values of greater than 0.5 and up to 2.0. In contrast, the term "strong donor monomer" is meant to include monomers having e values less than -1.5, and the term "warmly donor monomer" is meant to include monomers having e values from less than 0.5 to -1.5.

As used herein and in the claims, the term "fluorinated" is used to describe materials, typically polymers or copolymers, containing fluorine atoms.

The present invention relates to a composition comprising a fluorine-containing copolymer. The copolymer comprises at least 30 mole percent, in most cases at least 40 mole percent, typically at least 50 mole percent, and in part of the residues of the copolymer derived from the alternating sequence of donor monomer-receptor monomers having alternating monomer residue units of formula (1) At least 60 mol% and in other cases at least 75 mol%:

Formula 1

-[DM-AM]-

Where

DM is a residue from a donor monomer;

AM represents a residue from a receptor monomer.

The copolymer can be a 100% alternating copolymer of DM and AM. More specifically at least 15 mole% of the copolymer comprises a donor monomer which is an isobutylene type monomer having the general formula (I):

Formula I

here,

R ¹ is linear or branched C ₁ -C ₄ alkyl;

R ² is one or more methyl, linear, cyclic or branched C ₁ -C ₂₀ alkyl, alkenyl, aryl, alkaryl, and aralkyl.

In addition, at least 15 mole% of the copolymer comprises a receptor monomer. The group of R ² is one selected from epoxy, carboxylic acid, hydroxy, thiol, isocyanate, capped isocyanate, amide, amine, aceto acetate, methylol, methylol ether, oxazoline carbamate, and beta-hydroxyalkylamide It may also contain the above functional groups.

In the present invention, the copolymer is at least 5% by weight, in some cases at least 10% by weight, in other cases at least 15% by weight, at most 50% by weight, in some cases at most 40% by weight, in other cases at most 35% by weight, in part In this case, 30% by weight or less of fluorine is contained. The copolymer may contain fluorine in any numerical range, including the foregoing. In addition, the copolymer incorporates a substantial fraction of alternating residues of the mild donor monomer and the mild acceptor monomer as described above in formula (I). Receptor monomers will include vinyl monomers with fluoro and / or chloro substituents and may include acrylic acceptor monomers.

Accordingly, the composition of the present invention comprises a structural unit of formula (I)-[DM-AM]-as described above in the fluorine-containing copolymer, wherein the structural unit may specifically include a structural unit of formula (II) have:

Where

R ¹ and R ² are as described above;

R ³ is a group comprising one or both of chlorine and fluorine;

R ⁴ and R ⁵ are independently selected from H, Cl and F.

A particular advantage of the fluorine-containing copolymers of the present invention is their potentially low cost.

For donor monomers and acceptor monomers in-[DM-AM]-structural units, a non-limiting list of published e values for monomers that may be included as donor monomers and acceptor monomers is provided in Table 1 below. As follows:

Any suitable donor monomer can be used in the present invention. Suitable donor monomers that may be used include strong donor monomers and mild donor monomers. The present invention is particularly useful for preparing alternating copolymers in which mild donor molecules are used. Copolymers of the present invention will include mild donor monomers, such as isobutylene and diisobutylene, dipentene, isoprenol and 1-octene, represented by Formula I, and additionally other suitable mild donors It may include a monomer. Mild donor monomers of formula (I) are present in the copolymer composition at least 15 mol%, in some cases at least 25 mol%, typically at least 30 mol%, and in some cases at least 35 mol%. The mild donor monomer of formula (I) is present in the copolymer composition in an amount of up to 50 mol%, in some cases up to 47.5 mol%, typically up to 45 mol%, in some cases at least 40 mol%. The level of mild donor monomer of formula (I) used is determined by the properties introduced into the copolymer composition. Residues from the mild donor monomer of Formula I may be present in the copolymer composition in any numerical range as described above.

Suitable other donor monomers that may be used in the present invention include, but are not limited to, ethylene, butene, styrene, substituted styrene, methyl styrene, substituted styrene, vinyl ether, vinyl esters, vinyl pyridine, divinyl benzene, vinyl Naphthalene and divinyl naphthalene. Vinyl esters are vinyl esters of carboxylic acids and include but are not limited to vinyl acetate, vinyl butyrate, vinyl, 3,4-dimethoxybenzoate, and vinyl benzoate. The use of other donor monomers is optional, and when other donor monomers are present, they are at a level of at least 0.01 mol%, often at least 0.1 mol%, typically at least 1 mol%, in some cases at least 2 mol%, of the copolymer composition. exist. Other donor monomers may be present in amounts of up to 25 mol%, in some cases up to 20 mol%, typically up to 10 mol%, in some cases up to 5 mol%. The level of other donor monomers used is determined by the properties to be incorporated into the copolymer composition. Residues from other donor monomers may be present in the copolymer composition in any of the numerical ranges described above.

The copolymer composition comprises receptor monomers as part of alternating donor monomer-receptor monomers along the copolymer chain. The receptor monomer is of formula CR ⁴ ₂ = CR ³ R ⁵ , wherein R ³ is a group comprising one or both of chlorine or fluorine and R ⁴ and R ⁵ are independently selected from H, Cl, and F It may include a monomer having.

In addition, other suitable receptor monomers may be used. Suitable receptor monomers include strong receptor monomers and mild receptor monomers. A non-limiting class of suitable receptor monomers is described by Formula III below:

Where

W is selected from the crowd consisting of -CN, -X and -C (= 0) -Y, where Y is -NR ³ ₂ , -OR ⁵ -OC (= 0) -NR ³ ₂ , and -OR ⁴ ) Is selected from a crowd of

R ³ is selected from the group consisting of H, linear or branched C ₁ -C ₂₀ alkyl, and linear or branched C ₁ -C ₂₀ alkylol,

R ⁴ is H, poly (ethylene oxide), poly (propylene oxide), linear or branched C ₁ -C ₂₀ alkyl, alkylol, aryl and aralkyl, linear or branched C ₁ -C ₂₀ fluoroalkyl, fluorine Selected from the group consisting of roaryl and fluoroaralkyl, siloxane radicals, polysiloxane radicals, alkyl siloxane radicals, ethoxylated trimethylsilyl siloxane radicals, and propoxylated trimethylsilyl siloxane radicals,

R ⁵ is a divalent linear or branched C ₁ -C ₂₀ alkyl linking group,

X is a halide.

A class of mild receptor monomers that may be included in the copolymer composition of the present invention are acrylic receptor monomers. Suitable acrylic acceptor monomers include the compounds described by formula IV:

Where

Y is selected from the crowd consisting of -NR ³ ₂ , -OR ⁵ -OC (= O) -NR ³ ₂ , and -OR ⁴ ,

R ³ is selected from the group consisting of H, linear or branched C ₁ -C ₂₀ alkyl, and linear or branched C ₁ -C ₂₀ alkylol,

R ⁴ is H, poly (ethylene oxide), poly (propylene oxide), linear, cyclic or branched C ₁ -C ₂₀ alkyl, alkylol, aryl and aralkyl, linear or branched C ₁ -C ₂₀ fluoroalkyl , Fluoroaryl, and fluoroaralkyl, siloxane radicals, polysiloxane radicals, alkyl siloxane radicals, ethoxylated trimethylsilyl siloxane radicals, and propoxylated trimethylsilyl siloxane radicals;

R ⁵ is a divalent linear or branched C ₁ -C ₂₀ alkyl linking group.

Particularly useful types of acrylic acceptor monomers include those where Y is epoxy, carboxylic acid, hydroxy, thiol, isocyanate, capped isocyanate, amide, amine, aceto acetate, methylol, methylol ether, oxazoline carbamate and / or beta -A compound of formula IV comprising one or more functional groups in a hydroxyalkyl amide.

Examples of suitable acceptor monomers include, but are not limited to, chlorotrifluoroethylene, tetrafluoroethylene, trifluoroethylene, difluoroethylene, vinyl fluoride, hexafluoropropylene, and mixtures thereof, Optionally further acrylic acid, acrylic acid ester, acrylamide, N-alkyl substituted acrylamide, acrylonitrile, hydroxyethyl acrylate, hydroxypropyl acrylate, acrylic acid, methyl acrylate, ethyl acrylate, butyl acrylate, Isobutyl acrylate, isobornyl acrylate, dimethylaminoethyl acrylate, acrylamide, perfluoro methyl ethyl acrylate, perfluoro ethyl ethyl acrylate, perfluoro butyl ethyl acrylate, trifluoromethyl benzyl Acrylic ray , Perfluoro alkyl ethyl, acryloxyalkyl terminated polydimethylsiloxane, acryloxyalkyl tris (trimethylsiloxane silane), acryloxyalkyl trimethylsiloxy terminated polyethylene oxide, chlorotrifluoro ethylene, gly It is selected from the group consisting of cydyl arc related, 2-ethylhexyl acrylate, n-butoxy methyl acrylamide, and mixtures thereof.

The acrylic acceptor monomer is present at a level of at least 15 mol%, in some cases at least 25 mol%, typically at least 30 mol%, and in some cases at least 35 mol% in the copolymer composition. The acrylic acceptor monomer of formula III is present in the copolymer composition at levels of up to 50 mol%, in some cases up to 47.5 mol%, typically up to 45 mol%, in some cases up to 40 mol%. The level and type of acceptor monomer used is determined by the properties to be incorporated into the copolymer composition. Residues of the acceptor monomer may be present in the copolymer composition in any of the numerical ranges described above.

Suitable other mild receptor monomers that may be used in the present invention include, but are not limited to, acrylonitrile, methacrylonitrile, crotonic acid, vinyl alkyl sulfonate and acrolein. The use of other mild receptor monomers is optional, but when other mild receptor monomers are present, they are at least 0.01 mol%, often at least 0.1 mol%, typically at least 1 mol%, in some cases at least 2 mol%, of the copolymer composition Exists as. Other acceptor monomers may be present up to 35 mole percent, in some cases up to 25 mole percent, typically up to 15 mole percent, and in some cases up to 10 mole percent. The level of other acceptor monomers used is determined by the properties to be incorporated into the copolymer composition. Residues of other acceptor monomers may be present in the copolymer composition in any of the numerical ranges described above.

The compositions of the present invention have a molecular weight of at least 250, in most cases at least 500, typically at least 1,000 and in some cases at least 2,000. The molecular weight of the copolymers of the invention can be up to 1,000,000, in most cases up to 500,000, typically up to 100,000, in some cases up to 50,000. In certain applications, it will be required that the molecular weight of the copolymers of the present invention not exceed 30,000, in some cases not exceed 25,000, in other cases not exceed 20,000, and in certain cases not exceed 16,000. The molecular weight of the copolymer is selected according to the properties to be introduced into the copolymer composition. The molecular weight of the copolymer can vary in any numerical range as described above.

The polydispersity (PDI) of the copolymers of the present invention is not always important. The polydispersity of the copolymer is generally less than 4, in many cases less than 3.5, typically less than 3 and in some cases less than 2.5. As used herein and in the claims, the "polydispersity" is determined from the equation of (weight average molecular weight (Mw) / number average molecular weight (Mn)). The simple dispersion polymer had a PDI of 1.0. In addition, as used herein, Mn and Mw are measured from gel permeation chromatography using polystyrene standards.

The copolymer composition of the present invention may have all monomer residues introduced into the alternating structure. Non-limiting examples of copolymer segments having 100% alternating structure of diisobutylene (DIIB) and hexafluoropropylene (HFP) are shown in Formula V:

In most cases, however, the copolymers of the present invention are copolymers containing alternating and random segments, as shown by Formula VI, which are copolymers of DIIB, HFP and other monomers:

Formula VI depicts an embodiment of the invention in which the copolymer may include random segments as shown by underlined segments and alternating segments as shown in a box.

Random segments of the copolymer may contain donor or acceptor monomer residues that are not introduced into the copolymer composition by alternating structure. The random segments of the copolymer composition may further comprise residues from other ethylenically unsaturated monomers. As mentioned herein, all references to polymer segments derived from the alternating order of donor monomer-receptor monomer pairs are meant to include segments of monomer residues as shown by the box of Formula VI.

Other ethylenically unsaturated monomers include any suitable monomer that is not traditionally listed as a acceptor monomer or donor monomer.

Other ethylenically unsaturated monomers, the residues of monomer M of formula VI, are derived from one or more ethylenically unsaturated radically polymerizable monomers. As used herein and in the claims, terms such as "ethylenically unsaturated, radically polymerizable monomer" and the like refer to vinyl monomers, allylic monomers, olefins, and other ethylene radically polymerizable but not classified as donor monomers or acceptor monomers. It is meant to include unsaturated monomers.

The class of vinyl monomers from which M can be derived include, but are not limited to, monomer residues derived from monomers of Formula (VII):

Where

R ¹¹ , R ¹² , and R ¹⁴ are independently H, CF ₃ , straight or branched C ₁ -C ₂₀ alkyl, aryl, unsaturated straight or branched C ₂ -C ₁₀ alkenyl or alkynyl, halogen, C ₃ Unsaturated straight or branched C ₂ -C ₆ alkenyl substituted with -C ₈ cycloalkyl, heterocyclyl or phenyl;

R ¹³ is selected from the group consisting of H, C ₁ -C ₆ linear, cyclic, or branched alkyl, COOR ¹⁸ , wherein R ¹⁸ is H, an alkali metal, a C ₁ -C ₆ alkyl group, glycidyl and aryl It is chosen from a composed crowd.

Specific examples of other monomers, M, which can be used in the present invention include methacrylic monomers and allyl monomers. The residue of monomer M may be derived from one or more of C ₁ -C ₂₀ alkyl methacrylates in the alkyl group. Specific examples of the C ₁ -C ₂₀ alkyl methacrylate in the alkyl group, from which the monomer M can be derived, include, but are not limited to, methyl methacrylate, ethyl methacrylate, propyl methacrylate, isopropyl methacrylate. Latex, butyl methacrylate, isobutyl methacrylate, tert-butyl methacrylate, 2-ethylhexyl methacrylate, lauryl methacrylate, isobornyl methacrylate, cyclohexyl methacrylate, and 3 , 3,5-trimethylcyclohexyl methacrylate, as well as functional methacrylates such as hydroxyalkyl methacrylate, oxirane functional methacrylate, and carboxylic acid functional methacrylate. have.

The residue of monomer M may also be selected from monomers having more than one methacrylate group, for example methacrylic anhydride and diethylene glycol bis (methacrylate).

As used herein and in the claims, “allyl monomers” include monomers containing substituted and / or unsubstituted allyl functional groups, that is, one or more radicals represented by the following formula VIII:

Where

R ¹⁰ is hydrogen, halogen, or a C ₁ -C ₄ alkyl group.

Most commonly, R ¹⁰ is hydrogen or methyl and consequently the group of general formula VIII represents an unsubstituted (meth) allyl radical bearing both allyl and metallyl radicals. Examples of allyl monomers include, but are not limited to, (meth) allyl alcohols; (Meth) allyl ethers such as methyl (meth) allyl ether; Allylic esters of carboxylic acids such as (meth) allyl acetate, (meth) allyl butyrate, (meth) allyl 3,4-dimethoxybenzoate, and (meth) allyl benzoate.

The alternating copolymers of the present invention comprise the steps of (a) providing a donor monomer composition comprising at least one donor monomer of the structure of formula (I); (b) mixing the component (a) with an ethylenically unsaturated monomer composition comprising at least one acceptor monomer to form a total monomer composition; And (c) polymerizing the entire monomer composition in the presence of a free radical initiator. In an embodiment of the invention, the ethylenically unsaturated monomer composition comprises a monomer of the formula CR ⁴ ₂ = CR ³ R ⁵ , as described above.

In an embodiment of the process of the invention, the monomer of formula (I) is present in molar excess based on the amount of receptor monomer. Any excess of monomers of the structure of formula (I) may be used in the present invention to promote the formation of the desired alternating structure. The excess monomer of formula (I) is at least 10 mol%, in some cases up to 25 mol%, typically up to 50 mol%, in some cases up to 100 mol%, based on the amount of acrylic acceptor monomer. If the molar excess of monomer of formula (I) is too large, the process may not be economical on an industrial scale.

In a further embodiment of the process of the invention, the monomer having the formula CR ⁴ ₂ = CR ³ R ⁵ comprises at least 15 mole%, in some cases at least 17.5 mole%, typically at least 20 mole%, of the total monomer composition, In some cases at least 25 mole percent. The monomer of formula CR ⁴ ₂ = CR ³ R ⁵ may further be present in an amount of up to 50 mol%, in some cases up to 47.5 mol%, typically up to 45 mol%, in some cases up to 40 mol%. have. The level of formula CR ⁴ ₂ = CR ³ R ^{5 used} is determined by the properties to be introduced into the copolymer composition. The formula CR ⁴ ₂ = CR ³ R ⁵ monomer may be present in the monomer composition in any range of the foregoing values.

The ethylenically unsaturated monomer composition of the process of the invention may comprise other donor monomers as described above as well as other monomers indicated by M and as described above. The use of other mild receptor monomers is optional in the method of the present invention. If other mild receptor monomers are present, they are present in an amount of at least 0.01 mol%, often at least 0.1 mol%, typically at least 1 mol%, and in some cases at least 2 mol% of the total monomer composition. do. Other acceptor monomers may be present in amounts of up to 35 mole percent, in some cases up to 25 mole percent, typically up to 15 mole percent, and in some cases up to 10 mole percent. As used herein, the level of other acceptor monomers is determined by the properties introduced into the copolymer composition. Residues from other acceptor monomers may be present in the copolymer composition in any of the numerical ranges described above.

The use of other monomers, M, is optional in the process of the invention. If other monomers are present, they are present at levels of at least 0.01 mol%, often at least 0.1 mol%, typically at least 1 mol% and in some cases up to 2 mol% of the copolymer composition. Other monomers may be present in amounts of up to 35 mole percent, in some cases up to 25 mole percent, typically up to 15 mole percent, in some cases up to 10 mole percent. The level of other monomers used herein is determined by the properties to be incorporated into the copolymer composition. Residues from other monomers M may be present in the copolymer composition in any of the numerical ranges described above.

In an embodiment of the process of the invention, an excess of monomer of formula (I) is used and unreacted monomer of formula (I) is removed from the copolymer composition produced by evaporation. Removal of unreacted monomers is typically easily accomplished by applying a vacuum to the reaction vessel.

Any suitable free radical initiator may be used in the present invention. Suitable free initiators include, but are not limited to, thermal free radical initiators, photo-initiators, and redox initiators. Examples of suitable thermal free radical initiators include, but are not limited to, peroxide compounds, azo compounds and persulfate compounds.

Examples of suitable peroxide compound initiators include, but are not limited to, hydrogen peroxide, methyl ethyl ketone peroxide, benzoyl peroxide, di-t-butyl peroxide, di-t-amyl peroxide, dicumyl peroxide , Diacyl peroxide, decanoyl peroxide, lauroyl peroxide, peroxydicarbonate, peroxyester, dialkyl peroxide, hydroperoxide, peroxyketal, and mixtures thereof.

Examples of suitable azo compounds include, but are not limited to, 4-4'-azobis (4-cyanovaleic acid), 1-1'-azobiscyclohexanecarbonitrile), 2-2'-azobisio Butyronitrile, 2-2'-azobis (2-methylpropionamidine) dihydrochloride, 2-2'-azobis (2-methylbutyronitrile), 2-2'-azobis (propionitrile ), 2-2'-azobis (2,4-dimethylvaleronitrile), 2-2'-azobis (valeronitrile), 2,2'-azobis [2-methyl-N- (2 -Hydroxyethyl) propionamide], 4,4'-azobis (4-cyanopentanoic acid), 2,2'-azobis (N, N'-dimethyleneisobutyramidine), 2,2 ' -Azobis (2-amidinopropane) dihydrochloride, 2,2'-azobis (N, N'-dimethyleneisobutyramidine) dihydrochloride, and 2- (carbamoyl azo) -isobuty Ronitrile.

In an embodiment of the invention, the ethylenically unsaturated monomer composition and the free radical polymerization initiator are added and mixed separately and simultaneously to the donor monomer composition. The ethylenically unsaturated monomer composition and free radical polymerization initiator may be added to the donor monomer composition for a period of at least 15 minutes, in some cases at least 20 minutes, typically at least 30 minutes, and in some cases at least 1 hour. The ethylenically unsaturated monomer composition and free radical polymerization initiator may further be added to the donor monomer composition for up to 24 hours, in some cases up to 18 hours, typically up to 12 hours, in some cases up to 8 hours. The addition time of the ethylenically unsaturated monomer should be sufficient to maintain a moderate excess of donor monomer of formula (I) for the unreacted acrylic acceptor monomer to facilitate the formation of donor monomer-receptor monomer alternating segments. The addition time should not be long enough to make the process economically viable on an industrial scale. The addition time can vary within any numerical range described above.

After mixing, or during addition and mixing, monomer polymerization is carried out. The polymerization process of the present invention can be carried out at any suitable temperature. Suitable temperatures for the process of the invention may be at room temperature, at least 50 ° C, in most cases at least 60 ° C, typically at least 75 ° C, and in some cases at least 100 ° C. Suitable temperatures for the process of the invention may be further described below 300 ° C., in most cases below 275 ° C., typically below 250 ° C., and in some cases below 225 ° C. The temperature is high enough to promote good reactivity from the monomers and initiators used. However, the volatility and the corresponding partial pressure of the monomers define a practical upper limit for the temperature measured by the pressure rating of the reaction vessel. The polymerization temperature may vary within any numerical range described above.

The polymerization process of the present invention may be carried out at any suitable pressure. Suitable pressures for the process of the invention may be at least 1 psi, ie in many cases at least 5 psi, typically at least 15 psi, in some cases at least 20 psi. Suitable pressures for the process of the present invention may also be described to be up to 200 psi, in many cases up to 175 psi, typically up to 150 psi, in some cases up to 125 psi. The pressure is typically high enough to keep the monomers and initiator in liquid phase. The pressure used has a practical upper limit based on the pressure rating of the reaction vessel used. The pressure during the polymerization temperature can vary within any of the numerical ranges mentioned above.

Copolymers obtained from the process of the invention may also be used as starting materials for the preparation of other polymers by functional group modifications by methods known in the art. Functional groups that can be introduced by this method are epoxy, carboxylic acid, hydroxy, thiol, isocyanate, capped isocyanate, amide, amine, aceto acetate, methylol, methylol ether, oxazoline carbamate, and beta-hydr And oxyalkylamides.

For example, the copolymer of the method of the present invention comprising methyl acrylate will contain carbomethoxy groups. Carbomethoxy groups may be hydrolyzed to carboxyl groups or may be subjected to transesterification with alcohols to form esters of the corresponding alcohols. Using ammonia, the aforementioned methyl acrylate copolymers can be converted to amides or can be converted to the corresponding N-substituted amides using primary or secondary amines. Similarly, by using diamines, for example ethylene diamine, the aforementioned copolymers of the process of the invention can be converted to N-aminoethylamide or ethanolamine to N-hydroxyethylamide. . N-aminoethylamide functional groups may further be converted to oxazoline by dehydration. N-aminoethylamide may further be reacted with a carbonate such as propylene carbonate to produce the corresponding urethane functional copolymer. This conversion can be carried out to convert all carbomethoxy groups or only partially so that the carbomethoxy groups remain intact.

Epoxy groups can be introduced into the copolymers of the process of the invention either directly or indirectly by functional group modifications by using glycidyl acrylates in the copolymer preparation. An example of indirect process is the use of peracids such as peroxyacetic acid to oxidize the residual unsaturated moieties in the copolymer to the epoxy groups. Optionally, the carboxyl-functional copolymer can be hydrolyzed as described above and the carboxyl-functional copolymer can be treated with epichlorohydrin and then with alkali to produce an epoxy functional copolymer. Such modifications may also be carried out in whole or in part. The resulting epoxy-functional copolymer can further be reacted with a suitable active hydrogen containing reagent to form alcohols, amines or sulfides.

The hydroxyl groups can be introduced directly into the copolymer of the process of the invention using hydroxy-functional monomers such as hydroxyethyl acrylate, or can be introduced by functional group modification. By treating the carboxyl-functional copolymer described above with epoxy, a hydroxyl functional polymer can be prepared. Suitable epoxies include, but are not limited to, ethylene oxide, propylene oxide, butylene oxide, and glycidyl neodecanoate.

The aforementioned hydroxyl functional copolymers may further react to form other copolymers. For example, copolymers containing hydroxyethyl groups can be treated with carbamylation reagents such as methyl carbamate to produce the corresponding carbamate functional copolymer. By diketene or t-butyl acetoacetate, the hydroxyl groups can also be converted to acetoacetate esters.

Isocyanate functional copolymers may also be prepared. Copolymers of the process of the invention containing two or more hydroxyl groups can be treated with a diisocyanate, for example isophorone diisocyanate, to produce an isocyanate-functional polymer. The aforementioned primary amine functional copolymers can be phosgenated to produce isocyanate functional groups.

In an embodiment of the invention, the composition contains co-reactive functional groups.

In a specific embodiment, the composition is a thermosetting composition. In such embodiments, the composition comprises the above-described alternating copolymer and one or more other components. The copolymer contains reactive functional groups and other components contain functional groups reactive with the functional groups of the copolymer.

In embodiments of the invention, the functional groups of the copolymer include epoxy, carboxylic acid, hydroxy, thiol, isocyanate, capped isocyanate, amide, amine, aceto acetate, methylol, methylol ether, oxazoline carbamate, and May be one or more selected from the group consisting of beta-hydroxyalkylamides, and the functional groups of the other components are epoxy, carboxylic acid, hydroxy, thiol, amide, amine, oxazoline, aceto acetate, methylol, methylol ether, isocyanate, Capping isocyanate, beta hydroxyalkamide and carbamate. Typically, the functional group equivalent weight of the copolymer is 100 to 5,000 grams / equivalent and the functional group equivalent weight of other materials is 50 to 5,000 grams / equivalent.

In embodiments of the invention, the thermosetting composition may comprise additional fluorinated polymers. Additional fluorinated polymers can react with the functional groups of the other components described above such as epoxy, carboxylic acid, hydroxy, thiol, isocyanate, capped isocyanate, amide, amine, aceto acetate, methylol, methylol ether, oxa Functional groups selected from sleepy carbamate, and beta-hydroxyalkylamide. As a non-limiting example, additional fluorinated polymers are those described in US Pat. No. 4,345,057 to Yamabe et al., Which is incorporated herein by reference. Specific, non-limiting examples of additional fluorinated polymers that may be used include Lumiflon polymers available from Asahi Glass Company, Tokyo, Japan.

More specifically, the additional fluorinated polymer comprises 40 to 60 mole percent fluoroolefin units, 5 to 45 mole percent cyclohexyl vinyl ether units, 5 to 45 mole percent alkyl vinyl ether units, and 3 to 15 mole percent And at least one curable fluorocopolymer comprising hydroxyalkyl vinyl ether units. Any suitable fluoroolefin monomer can also be used to prepare additional curable fluorocopolymers. Suitable fluoroolefins that may be used include, but are not limited to, chlorotrifluoroethylene, tetrafluoroethylene, trifluoroethylene, difluoroethylene, hexafluoropropylene and vinyl fluoride.

Typically, in the thermosetting compositions of the present invention, the molar or equivalent ratio of the functional groups in the alternating copolymers of the present invention, and optionally additional curable fluorocopolymers with functional groups in one or more other components, is from 0.7: 1 to 2: 1. to be.

Specific embodiments of the present invention provide a non-gelling copolymer composition comprising a fluorine-containing copolymer of the invention containing a functional group and optionally a curable fluoropolymer comprising a functional group, and a copolymer as one or more other components. A liquid thermosetting composition comprising a crosslinking agent having two or more functional groups reacting with a functional group of is provided.

In the liquid thermosetting composition, the functional group in the fluorinated copolymer is any suitable functional group as described above. The crosslinker will have a suitable functional group to react with the functional group in the copolymer. Suitable functional groups for the crosslinker include, but are not limited to, epoxy, carboxylic acid, hydroxy, thiol, amide, amine, oxazoline, aceto acetate, methylol, methylol ether, isocyanate, capped isocyanate, beta Hydroxyalkamide, and carbamate.

The equivalent ratio of equivalents of functional groups in the crosslinker to functional groups in the fluorinated functional copolymer is typically in the range of 1: 3 to 3: 1. The crosslinker is present in the liquid thermosetting composition in an amount of 1 to 45 weight percent based on the total weight of the resin solid and the fluorinated functional copolymer is present in an amount of 55 to 99 weight percent based on the total weight of the resin solid. do.

Non-limiting examples of the liquid thermosetting compositions of the present invention are those wherein the functional group of the fluorinated copolymer is hydroxy and the functional group of the crosslinker is capped polyisocyanate, wherein the capping group of the capped polyisocyanate crosslinker is one or more hydroxy. Functional compounds, 1H-azole, lactam, ketoxime, and mixtures thereof. The capping group is phenol, p-hydroxy methylbenzoate, 1H-1,2,4-triazole, 1H-2,5-dimethyl pyrazole, 2-propanone oxime, 2-butanone oxime, cyclohexanone oxime , e-caprolactam, or mixtures thereof. The polyisocyanates of the capped polyisocyanate crosslinker include 1,6-hexamethylene diisocyanate, cyclohexane diisocyanate, α, α'-xylene diisocyanate, α, α, α ', α'-tetramethylxylene diisocyanate At least one of 1-isocyanato-3,3,5-trimethyl-5-isocyanatomethylcyclohexane, diisocyanato-dicyclohexylmethane, dimer of polyisocyanate, or trimer of polyisocyanate.

If the fluorinated copolymer has a hydroxy functional group, the hydroxy equivalent weight will typically be between 100 and 10,000 grams / equivalent. The equivalent ratio of isocyanate equivalents in the capped polyisocyanate crosslinker to hydroxy equivalents in the hydroxy functional fluorinated copolymer will typically be from 1: 3 to 3: 1. In such embodiments, the capped polyisocyanate crosslinker is present in the liquid thermosetting composition in an amount of 1 to 45 weight percent based on the total weight of the resin solid, and the hydroxy functional fluorinated copolymer is the total weight of the resin solid. Present in an amount of from 55 to 99% by weight.

Another non-limiting example of the liquid thermosetting composition of the present invention is that the fluorinated copolymer has an epoxy functional group and the crosslinker is a C ₄ -C ₂₀ carboxylic acid functional compound. The carboxylic acid crosslinker may be one or more of dodecaneic acid, azelaic acid, adipic acid, 1,6-hexanediacid, succinic acid, pimelic acid, sebacic acid, maleic acid, citric acid, itaconic acid, or aconic acid.

Further non-limiting examples of the liquid thermosetting compositions of the invention are those in which the fluorinated copolymer has carboxylic acid functional groups and the crosslinker is a beta-hydroxyalkylamide compound. The liquid thermoset composition may further comprise a second polycarboxylic acid functional material selected from the group consisting of C ₄ -C ₂₀ aliphatic carboxylic acids, polymeric polyanhydrides, polyesters, polyurethanes, and mixtures thereof. Beta-hydroxyalkylamide can be represented by the following formula (IX).

Where

R ²⁴ is H or C ₁ -C ₅ alkyl,

R ²⁵ is H, C ₁ -C ₅ alkyl or a group of formula X:

In the above formula

R ²⁴ is as described above;

E is a monovalent or polyvalent organic radical derived from a saturated, unsaturated or aromatic hydrocarbon radical, including chemical bonds or substituted hydrocarbon radicals of 2 to 20 carbon atoms;

m is 1 or 2;

n is 0 or 2;

m + n is two or more.

The liquid thermosetting composition of the present invention is preferably used as a film-forming (coating) composition and may contain additional components commonly used in such compositions. Optional ingredients such as plasticizers, surfactants, thixotropic agents, anti-gassing agents, organic cosolvents, flow control agents, antioxidants, UV light absorbers, and similar additives conventional in the art It may also be included in the composition. Such components are typically present in amounts up to about 40% by weight, based on the total weight of the resin solids.

The liquid thermosetting composition of the present invention may be water based, but generally may also be solvent based. Suitable solvent carriers are known in the art of coating formulations and include various esters, ethers and aromatic solvents (mixtures of which are also included). The composition typically has a total solids content of about 40 to about 80 weight percent. The liquid thermosetting composition of the present invention will have a VOC content of less than 4% by weight, typically less than 3.5% by weight and in many cases less than 3% by weight.

The liquid thermosetting composition of the present invention may comprise color pigments commonly used in surface coatings, or may be used as a monocoating which is a colored coating. Suitable color pigments include, for example, inorganic pigments such as titanium dioxide, iron oxide, chromium oxide, lead chromate, and carbon black, and organic pigments such as phthalocyanine blue and phthalocyanine green. Mixtures of the aforementioned pigments may also be used. Suitable metallic pigments include, in particular, aluminum flakes, copper bronze plates, and metal oxide coated mica, nickel flakes, tin flakes, and mixtures thereof.

Generally, pigments are introduced into the coating composition in amounts up to about 80% by weight based on the total weight of the coating solids. Metallic pigments are used in amounts of about 0.5 to about 25 weight percent based on the total weight of the coating solids.

In another embodiment, a thermosetting composition of the present invention comprises a co-polymer of a composition comprising a reactant having two or more functional groups, and a fluorine-containing copolymer of the present invention having functional groups and an optional curable fluorocopolymer having functional groups. A reactive solid particulate mixture or powder. In powder thermosetting compositions, the reactants are epoxy, carboxylic acid, hydroxy, thiol, amide, amine, oxazoline, aceto acetate, methylol, methylol ether, isocyanate, capped isocyanate, beta hydroxyalkamide, and carbamate It may have a functional group selected from among. The functional groups of the fluorine-containing copolymer are as described above. The functional groups of the reactants will react with the functional groups in the copolymer.

Fluorine-containing functional copolymers typically have a functional group equivalent weight of 100 to 5,000 grams / equivalent, with an equivalent ratio of functional groups to functional copolymer functional groups in the reactants ranging from 1: 3 to 3: 1. Typically, the reactants are present in an amount of 1 to 45 weight percent based on the total weight of the resin solids, and the functional copolymer is present in an amount of 55 to 99 weight percent based on the total weight of resin resin.

In an embodiment of the powder thermosetting composition of the present invention, the functional group of the fluorinated copolymer is a hydroxy functional group and the reactant is a capped polyisocyanate crosslinker. In this embodiment, the capping group of the capped polyisocyanate crosslinker is one or more hydroxy functional compounds, 1H-azole, lactam, and ketoxime. The capping group is phenol, p-hydroxy methylbenzoate, 1H-1,2,4-triazole, 1H-2,5-dimethyl pyrazole, 2-propanone oxime, 2-butanone oxime, cyclohexanone oxime And e-caprolactam. The polyisocyanates of the capped polyisocyanate crosslinker include 1,6-hexamethylene diisocyanate, cyclohexane diisocyanate, α, α'-xylene diisocyanate, α, α, α ', α'-tetramethylxylene diisocyanate , 1-isocyanato-3,3,5-trimethyl-5-isocyanatomethylcyclohexane, 2,4,4-trimethyl hexamethylene diisocyanate, 2,2,4-trimethyl hexamethylene diisocyanate At least one of diisocyanato-dicyclohexylmethane, a dimer of the polyisocyanate, and a trimer of polyisocyanate.

Fluorinated hydroxy functional copolymers typically have a hydroxy equivalent weight of 100 to 10,000 grams / equivalent, with an equivalent ratio of equivalents of isocyanate in the capped polyisocyanate crosslinker to equivalents of hydroxy equivalent in the hydroxy functional copolymer. 3 to 3: 1. Typically, the capped polyisocyanate crosslinker is present in an amount of 1 to 45 weight percent based on the total weight of the resin solids and the hydroxy functional copolymer is 55 to 99 weight percent based on the total weight of the resin solids. Exists in the amount of.

In another embodiment of the powder thermosetting composition, the functional group of the fluorinated copolymer is an epoxy functional group and the reactant is a carboxyl functional reactant having 4 to 20 carbon atoms. The carboxylic acid reactant is typically one or more of dodecaneic acid, azelaic acid, adipic acid, 1,6-hexanediacid, succinic acid, pimelic acid, sebacic acid, maleic acid, citric acid, itaconic acid, and aconic acid.

In a further embodiment of the powder thermosetting composition, the functional group of the fluorinated copolymer is a carboxyl based functional group and the reactant is beta-hydroxyalkylamide. In such embodiments, the powder thermosetting composition may further include one or more of a second polycarboxylic acid, typically a C ₄ -C ₂₀ fatty acid carboxylic acid, a polymer polyanhydride, polyester, polyurethane, and mixtures thereof. Beta-hydroxyalkylamides typically include the compounds represented by formula (IX) described above.

The powder thermosetting compositions of the invention may also comprise one or more curing catalysts for catalyzing the reaction between the crosslinker and the functional copolymer. Useful catalyst classes include metal compounds, in particular organotin compounds, and tertiary amines. Examples of organotin compounds include, but are not limited to, tin (II) salts of carboxylic acids, such as tin (II) acetate, tin (II) octanoate, tin (II) ethylhexanoate and tin (II) ) Laurate; Tin (IV) compounds such as dibutyltin oxide, dibutyltin dichloride, dibutyltin diacetate, dibutyltin dilaurate, dibutyltin maleate, and dioctyltin diacetate. . Examples of suitable tertiary amine catalysts include, but are not limited to, diazabicyclo [2.2.2] octane and 1,5-diazabicyclo [4,3,0] non-5-ene. Preferred catalysts include tin (II) octanoate and dibutyltin (IV) dilaurate.

The powder thermosetting compositions of the invention may also be pigments and fillers. Examples of pigments include, but are not limited to, inorganic pigments such as titanium dioxide and iron oxides; Organic pigments such as phthalocyanine, anthraquinone, quinacridone and thioindigo; And carbon black. Examples of fillers include, but are not limited to, silica, such as precipitated silica, clays, and barium sulphate. When used in the compositions of the present invention, the pigments and fillers are typically present in amounts of 0.1% to 70% by weight, based on the total weight of the thermosetting composition. More generally, the thermosetting compositions of the invention are used as transparent compositions that are substantially free of pigments and fillers.

The powder thermosetting compositions of the invention optionally modify and optimize waxes, flow regulators such as poly (2-ethylhexyl) acrylate, degassing additives such as benzoin, coating properties for flow and wetting. Additives such as auxiliary resins, antioxidants, and ultraviolet light absorbers. Examples of useful antioxidants and UV light absorbers include those commercially available from Ciba-Geigy under the trade names IRGANOX and TINUVIN. When used, such optional additives are present in amounts up to 20% by weight, based on the total weight of the thermosetting composition.

Powder thermoset compositions of the invention are typically by dry blending hydroxy functional polymers, crosslinkers, and additives such as flow regulators, degassing agents, and catalysts in a blender, such as Henshel blade blender. Are manufactured. The blend is operated for a period of time sufficient to produce a homogeneous dry blend of the material charged therein. The homogeneous dry blend can then be melt blended in an extruder, for example a twin screw co-rotating extruder, to operate in a temperature range of 80 ° C. to 140 ° C., for example 100 ° C. to 125 ° C. . When the extrudate of the thermosetting composition of the invention is cooled and used as a powder coating composition, it is typically milled, for example to have an average particle diameter of 15 to 30 μm.

The invention also

(A) applying a thermosetting composition to a substrate;

(B) coalescing the thermosetting composition to form a substantially continuous film; And

(C) curing the thermosetting composition to a method for coating a substrate.

Thermosetting compositions are typically the liquid thermosetting compositions or powder thermosetting compositions described above. Thermosetting compositions include copolymer compositions of the present invention comprising a functional fluorinated copolymer as described above and a crosslinking agent having at least two functional groups reactive with the functional groups of the functional copolymer.

The above-mentioned thermosetting composition can be applied on a variety of substrates, substrates to which they are attached include wood; Metal substrates such as ferrous and aluminum substrates, glass, plastics, and sheet mold compound-based plastics.

The compositions may be applied by conventional means, including blushing, dipping, flow coating, spraying, and the like, but they are often applied by spraying. Conventional spraying techniques and apparatus for air spraying and electrostatic spraying and manual or automatic methods can also be used. Substrates which can be coated by the process of the invention are, for example, wood, metal, glass and plastics.

The thermosetting composition of the present invention may be applied to the substrate by any suitable means known to those skilled in the art. The thermosetting composition may be in the form of a dry powder or optionally a liquid medium. When the substrate is electrically conductive, the thermosetting composition is typically electrostatically applied. Electrostatic spray coating is generally a method of drawing a thermosetting composition from a fluidized layer and driving it through a corona field. Particles of the thermosetting composition are attracted and deposited onto an electrically conductive substrate that is charged and grounded as they pass through the corona field. As charged particles accumulate, the substrate is insulated, thereby limiting further particle deposition. This insulation phenomenon typically limits the film build thickness of the deposited composition to a maximum of 3-6 mils (75-150 μm).

Optionally, where the substrate is not electrically conductive, such as in many plastic substrates, the substrate is typically preheated before the thermosetting composition is applied. The preheated temperature of the substrate is above the melting point of the thermosetting composition, but lower than their curing temperature. By spray application onto a preheated substrate, a film backbone of, for example, 10-20 mils (254-508 탆) thermosetting composition, over 6 mils (150 탆) is achieved.

If the thermosetting composition is a liquid, the composition is allowed to coalesce to form a substantially continuous film on the substrate. Typically the film thickness is about 0.01 to about 5 mils (about 0.254 to about 127 μm), preferably about 0.1 to about 2 mils (about 2.54 to about 50.8 μm). The film is formed on the surface of the substrate by removing solvent, ie organic solvent and / or water, out of the film by heating or air drying period. Preferably, heating is performed only for a short time, sufficient to ensure that any subsequently applied coating can be applied to the film without dissolving the composition. Suitable drying conditions will depend on the specific composition, but generally a drying time of about 1 to 5 minutes at a temperature of about 68 to 250 ° F. (20 to 121 ° C.) will be appropriate. More than one coating of the composition may be applied for optimal appearance. In between coatings, previously applied coatings may be flashed. That is, it may be exposed to ambient conditions for about 1 to 20 minutes.

After application to the substrate, the thermosetting composition is then coalesced to form a substantially continuous film. Adhesion of the applied composition is generally accomplished by heating to a temperature above the melting point of the composition but below its curing temperature. In the case of a preheated substrate, the application and adhesion steps can be achieved in essentially one step.

The coalesced thermosetting composition is cured by applying heat. As used herein and in the claims, “cured” means, for example, a three-dimensional crosslink formed by covalent bond formation between the free isocyanate group of the crosslinker and the hydroxy group of the polymer. The temperature at which the thermosetting composition of the invention is cured varies and depends in part on the type and amount of catalyst used. Typically, the thermosetting composition has a curing temperature in the range of 130 ° C. to 160 ° C., for example 140 ° C. to 150 ° C.

According to the present invention, there is further provided a multicomponent composite coating composition comprising a undercoat film deposited from a coloring film-forming composition and a pigment-free top coat applied on at least a portion of the undercoat film. The coating of the undercoat or topcoat or both may comprise the liquid thermosetting composition or powder thermosetting composition described above. Multicomponent composite coating compositions as described above are referred to as color-plus-clear coating compositions.

The colored film forming composition to be deposited into the undercoat can be any composition useful in coating applications, specifically in automotive applications where color-plus-transparent coating compositions are widely used. Colored film-forming compositions typically comprise a dendritic binder and a pigment that acts as a colorant. Particularly useful dendritic binders are acrylic polymers, polyesters including alkyds, polyurethanes, and copolymer compositions of the invention.

The dendritic binder for the colored film-forming undercoat composition can be an organic solvent-based material as disclosed in US Pat. No. 4,220,679, paragraphs 2, 24, 4, 40. In addition, waterborne coating compositions as described in US Pat. No. 4,403,003, US Pat. No. 4,147,679, and US Pat. No. 5,071,904 may be used as binders in the coloring film-forming composition.

The colored film-forming undercoat composition is colored and may also contain metallic pigments. Examples of suitable pigments include those disclosed in US Pat. No. 4,220,679, US Pat. No. 4,403,003, US Pat. No. 4,147,679, and US Pat. No. 5,071,904.

Components that may optionally be present in the colored film-forming undercoat compositions include those known in the art of formulated surface coatings, including surfactants, flow control agents, thixotropic agents, fillers, degassing agents, organic co-solvents, catalysts, and the like. Other conventional adjuvants. Examples of such optional materials and suitable amounts are disclosed in US Pat. No. 4,220,679, US Pat. No. 4,403,003, US Pat. No. 4,147,679, and US Pat. No. 5,071,904.

The colored film-forming undercoat composition may be applied to the substrate by any of conventional coating techniques, such as blushing, spraying, dipping or flow, but most commonly applied by spraying. Conventional spraying techniques and apparatus for air spraying, air-member spraying, and electrostatic spraying using manual or automatic methods can be used. The colored film-forming composition is typically applied in an amount sufficient to provide a undercoat with a film thickness of 0.1 to 5 mils (2.5 to 125 μm), preferably 0.1 to 2 mils (2.5 to 50 μm).

After depositing the colored film-forming undercoat composition onto the substrate and substantially before applying the pigment-free glass topcoat, the undercoat can be cured or optionally dried. When the deposited undercoat is dried, the organic solvent and / or water is discharged from the undercoat film by passing air or heating to the surface of the undercoat. Appropriate drying conditions will depend on the specific undercoat composition used and the ambient humidity for the particular waterborne composition. Generally, the deposited undercoat is dried at a temperature of 21 ° C. to 93 ° C. for 1 to 15 minutes.

A substantially pigment-free top coat is applied to the deposited undercoat by any method known to be coated. In an embodiment of the invention, a substantially pigment free top coat is applied by an electrostatic spray coating method as described herein above. When a substantially pigment-free top coat is applied over the deposited undercoat which is already dried, the two coatings can be co-cured to form the multicomponent composite coating composition of the present invention. Both the undercoat and the topcoat can be heated together to cure the two layers together. Typically curing conditions of 130 to 160 ° C. for 20 to 30 minutes are used. Substantially pigmentless top coats typically have a thickness of 0.5 to 6 mils (13 to 150 μm), for example 1 to 3 mils (25 to 75 μm).

The invention is described in more detail in the following examples, which are intended to be illustrative only, and it will be apparent to those skilled in the art that many modifications and variations thereof are possible. Unless otherwise noted, all parts and contents are by weight.

Examples 1 to 3

This example illustrates the synthesis of the fluorinated alternating copolymers of the present invention. The following components were used in the polymerization.

Charge 1 was added to the reaction flask equipped with a shaker, thermocouple and nitrogen injector. The flask was sealed, placed under a blanket of nitrogen and heated to 130 ° C. Charge 2 was then added to the reactor for 2.5 hours. 15 minutes after the start of Charge 2, Charge 3 and Charge 4 were added simultaneously to the reactor for 2 hours. During the addition of the monomer, the temperature of the reactor was maintained at 130-150 ° C., the pressure for diisobutylene was maintained at about 130 psi and the pressure for isobutylene was maintained at about 400 psi. After addition of Charges 2, 3 and 4, the reaction mixture was kept at 150 ° C. for 2 hours. The reactor was then cooled to 25 ° C. Gas chromatography analysis of the reaction mixture showed that all acrylates had reacted. The reported solids of the resulting polymer were measured at 110 ° C. for 1 hour. Then, the reaction flask was mounted for simple vacuum distillation, and the reaction mixture was raised to 155 ° C to remove unreacted diisobutylene or isobutylene. Subsequently, the coating composition was prepared using the vacuum-removed resin. Molecular weights were determined by gel permeation chromatography using polystyrene standards.

Examples 4-6

Coating compositions were prepared using the following components.

The resin was filled into paint cans and various pigments were added according to the mixing order. The mixture was then added to the mixing grinder and ground by zirconia medium until Hegman grind was obtained 7+. This formed one component of the two component composition. Component 2 was added to the remaining ingredients in the order indicated in the second vessel and mixed until a homogeneous mixture was formed. The two components were kept separated until just before application.

The coating composition was applied to both the galvanized steel substrate and the aluminum substrate as shown in the table below. The coating was cured for the temperature and time indicated in the table. The thickness of the dry film (unit: mill) is recorded in the table below. After curing, 60 ° gloss, T-bending flexibility, pencil hardness, reversible impact strength, and resistance to methyl ethyl ketone solvent were measured. 60 ° gloss was measured by a 60 ° gloss meter from BYK-Gardner Instrument Company.

The T-bending test evaluated the loss of adhesion and cracking after bending the coated panel at various angles. The first figure indicates how many times the bending diameter is the steel panel thickness. For example, "3" indicates that the bending diameter is three times the thickness of the steel panel before the loss of adhesion is recognized. The loss of adhesion is measured by placing and pressing a piece of adhesive tape against the film surface and then quickly peeling off the tape from the film. The second value is the subjective value associated with the crack. Grades are assigned on a scale of 1-9. 9 indicates that there is no crack and the film is not removed by the tape, while zero severe crack and the tape is completely removed by the tape.

Pencil hardness is a measure of coating resistance to scouring of pencils. The scale of pencil hardness starts with 4B indicating a relatively soft coating and increases to 10H indicating a relatively hard coating. Scales are from 4B, 3B, 2B, B, HB, F, H, 2H, 3H to 10H. The coating was marked with a pencil of increasing hardness until the pencil was scratched or etched into the surface.

Reversible impact resistance was measured by applying a 60 inch-pound reversible impact to the cured coating according to ASTM D2794. After the adhesive tape piece was pressed onto the film, the impacted film was visually evaluated for the removal amount and crack amount of the film after the film was quickly peeled off. The results are marked as pass (P) or fail (F), where P indicates no crack and the film is not removed by the tape, and F means that crack and / or film removal occurs.

Solvent resistance tests were performed with methyl ethyl ketone (MEK). Saturate the cloth with MEK and rub back and forth (double friction) until the coating is damaged (MEK damage value) and until the coating is removed from the substrate (MEK value, value 100 means the coating is not removed). . The values in the table below are due to double friction.

The results demonstrate the excellent balance between film hardness and flexibility as well as the durability of the coatings derived from thermosetting compositions containing the fluorine-containing copolymers of the present invention.

The present invention has been described with specific details of particular embodiments. This is not to be considered as limiting the scope of the present invention, as long as the above details are included within the scope of the appended claims.

Claims (28)

A composition comprising a fluorine-containing copolymer composed of 50 mole% or more of residues having alternating structural units of the formula (1) Wherein said copolymer contains at least 5% by weight of fluorine and said copolymer is prepared by polymerizing a molar excess of a monomer of formula (I) based on the amount of acceptor monomer: Formula 1 -[DM-AM]- Where DM represents a moiety derived from a donor monomer of formula (I); AM represents a residue derived from a receptor monomer: Formula I

[here, R ¹ is linear or branched C ₁ -C ₄ alkyl; R ² is selected from the group consisting of methyl, linear, cyclic or branched C ₁ -C ₂₀ alkyl, alkenyl, aryl, alkaryl, and aralkyl]. The method of claim 1, Wherein the alternating structural units of formula (1) in the fluorine-containing copolymer comprise residues having structural units of formula (II) Formula II

Where R ¹ and R ² are as defined in claim 1; R ³ is a group containing a halide selected from the group consisting of chlorine and fluorine; R ⁴ and R ⁵ are independently selected from the crowd consisting of H, Cl and F. The method of claim 1, A composition wherein the copolymer further comprises one or more residues derived from other ethylenically unsaturated acrylic monomers represented by Formula IV: Formula IV

Where Y is selected from the crowd consisting of —NR ³ ₂ , —OR ⁵ —OC (═O) —NR ³ ₂ , and —OR ⁴ ; R ³ is selected from the group consisting of H, linear or branched C ₁ -C ₂₀ alkyl, and linear or branched C ₁ -C ₂₀ alkylol; R ⁴ is H, poly (ethylene oxide), poly (propylene oxide), linear, cyclic or branched C ₁ -C ₂₀ alkyl, alkylol, aryl alkaryl and aralkyl, linear or branched C ₁ -C ₂₀ In the crowd consisting of fluoroalkyl, fluoroaryl, and fluoroaralkyl, siloxane radicals, polysiloxane radicals, alkyl siloxane radicals, ethoxylated trimethylsilyl siloxane radicals, and propoxylated trimethylsilyl siloxane radicals Selected; R ⁵ is a divalent linear or branched C ₁ -C ₂₀ alkyl linking group. The method of claim 3, wherein One selected from the group consisting of Y is epoxy, carboxylic acid, hydroxy, thiol, isocyanate, capped isocyanate, amide, amine, aceto acetate, methylol, methylol ether, oxazoline carbamate and beta-hydroxyalkylamide Composition comprising at least one functional group. The method of claim 2, A composition in which the structural unit of formula (II) of the copolymer constitutes 30 mol% or more of the copolymer. The method of claim 1, And the donor monomer is at least one selected from the group consisting of isobutylene, diisobutylene, isoprenol, 1-octene and dipentene. The method of claim 1, Receptor monomer is selected from the group consisting of chlorotrifluoroethylene, tetrafluoroethylene, trifluoroethylene, difluoroethylene, vinyl fluoride, hexafluoropropylene and mixtures thereof, optionally further acrylic acid, acrylic acid At least one selected from esters, acrylamides, N-alkyl substituted acrylamides, acrylonitrile and mixtures thereof. The method of claim 1, Wherein the copolymer further comprises one or more residues derived from other ethylenically unsaturated monomers of formula (VII): Formula VII

Where R ¹¹ , R ¹² and R ¹⁴ are independently H, halide, CF ₃ , straight or branched C ₁ -C ₂₀ alkyl, C ₆ -C ₁₂ aryl, unsaturated straight or branched C ₂ -C ₁₀ alkenyl or alkyne One and selected from the group consisting of unsaturated straight or branched chain C ₂ -C ₆ alkenyl substituted with halogen, C ₃ -C ₈ cycloalkyl, heterocyclyl or phenyl; R ¹³ is selected from the group consisting of H, halide, C ₁ -C ₆ alkyl, and COOR ¹⁸ , Wherein R ¹⁸ is selected from the group consisting of H, an alkali metal, a C ₁ -C ₆ linear, cyclic, or branched alkyl group, glycidyl and aryl. The method of claim 8, And the other ethylenically unsaturated monomer is at least one selected from the group consisting of methacrylic acid monomers and allyl monomers. The method of claim 1, The copolymer has a number average molecular weight of 500 to 16,000 and a polydispersity of less than 4. The method of claim 1, (a) a copolymer and (b) at least one other component, At this time, component (a) contains a reactive functional group, and component (b) contains a functional group reactive with the functional group of component (a) Composition. The method of claim 11, A composition that is a thermosetting composition. delete The method of claim 11, The functional group of the copolymer consists of epoxy, carboxylic acid, hydroxy, thiol, isocyanate, capped isocyanate, amide, amine, aceto acetate, methylol, methylol ether, oxazoline carbamate, and beta-hydroxyalkylamide At least one composition selected from the crowd. The method of claim 11, The functional groups of component (b) are epoxy, carboxylic acid, hydroxy, thiol, amide, amine, oxazoline, aceto acetate, methylol, methylol ether, isocyanate, capped isocyanate, beta hydroxyalkamide, and carbamate The composition selected from the crowd consisting of. The method of claim 11, Component (a) has a functional group equivalent weight of 100 to 5,000 grams / equivalent. The method of claim 11, Component (a) has 40 to 60 mole percent fluoroolefin units, 5 to 45 mole percent cyclohexyl vinyl ether units, 5 to 45 mole percent alkyl vinyl ether units, and 3 to 15 mole percent hydroxyalkyl vinyl A composition further comprising a curable fluorocopolymer comprising ether units. The method of claim 17, Wherein the fluoroolefin is at least one selected from the group consisting of chlorotrifluoroethylene, tetrafluoroethylene, trifluoroethylene, difluoroethylene, hexafluoropropylene, and vinyl fluoride. The method of claim 11, A composition wherein the ratio of functional groups of component (a) to functional groups of component (b) is from 0.7: 1 to 2: 1. A substrate in which at least a portion of the substrate is coated with the composition according to claim 12. A substrate in which at least a portion of the substrate is coated with the composition according to claim 11. A substrate in which at least a portion of the substrate is coated with the composition according to claim 17. (A) a undercoat layer deposited from the colored film-forming undercoat thermosetting composition; And (B) a topcoat film deposited substantially from the topcoat composition over at least a portion of the undercoat layer, wherein the topcoat is substantially free of pigment, Wherein the one or both of component (A) and component (B) comprise the composition according to claim 12. (A) a undercoat layer deposited from the colored film-forming undercoat thermosetting composition; And (B) a topcoat film deposited substantially from the topcoat composition over at least a portion of the undercoat layer, wherein the topcoat is substantially free of pigment, Wherein the one or both of component (A) and component (B) comprise the composition according to claim 11. (A) a undercoat layer deposited from the colored film-forming undercoat thermosetting composition; And (B) a topcoat film deposited substantially from the topcoat composition over at least a portion of the undercoat layer, wherein the topcoat is substantially free of pigment, Wherein the one or both of component (A) and component (B) comprise the composition according to claim 17. A substrate wherein at least a portion of the substrate is coated with the multilayer composite coating according to claim 23. A substrate wherein at least a portion of the substrate is coated with the multilayer composite coating according to claim 24. A substrate wherein at least a portion of the substrate is coated with the multilayer composite coating according to claim 25.