MXPA01002083A

MXPA01002083A - Thermosetting compositions containing carboxylic acid functional polymers and epoxy functional polymers prepared by atom transfer radical polymerisation

Info

Publication number: MXPA01002083A
Application number: MXPA/A/2001/002083A
Authority: MX
Inventors: Karen A Barkac; Simion Coca; James R Franks; Kurt A Humbert; Paul H Lamers; Roxalana L Martin; Dwyer James B O; Kurt G Olson; Daniela White
Original assignee: Ppg Industries Ohio Inc
Priority date: 1998-08-31
Filing date: 2001-02-27
Publication date: 2001-12-04

Abstract

A thermosetting composition comprising a co-reactable solid, particulate mixture of (a) polycarboxylic acid functional polymer, and (b) epoxy functional polymer, is described. The polycarboxylic acid functional polymer and epoxy functional polymer are each prepared by atom transfer radical polymerization and have well defined polymer chain architecture and polydispersity index of less than 2.5. The thermosetting compositions of the present invention have utility as powder coatings compositions.

Description

COMPOSITIONS TERMOENDURE C I BL E S CONTAINING CARBOXY ACID POLYMERS L I CO - FUNC I ONAL E S AND EPOXY - FUNCTIONAL POLYMERS PREPARED BY POLIMERI ZATION OF RADICALS BY ATOMIC TRANSFER FIELD OF THE INVENTION The present invention relates to thermosetting compositions of one or more polycarboxyli-co-functional acid polymers and one or more epoxy-functional polymers. The functional polycarboxylic acid polymer and the epoxy functional polymer are each prepared by radical polymerization by atomic transfer and have a well defined polymer chain structure, molecular weight and molecular weight distribution. The present invention also relates to methods of coating a substrate, to substrates coated by such methods and to composite coating compositions.

BACKGROUND OF THE INVENTION The reduction of the environmental impact of coating compositions, in particular that associated with air emissions of volatile organic compounds during their use, has been an area of increasing research and development. in recent years. As a result, the interest deposited on powder coatings has been increasing due, in part, to their inherently low volatile organic content (VOC), which significantly reduces air emissions during the application process. While both thermoplastic and thermosetting powder coating compositions can be purchased commercially, thermosetting powder coatings are typically more desirable because of their superior physical properties, for example hardness and solvent resistance. Low VOC coatings are particularly desirable in the original equipment (OEM) manufacturing markets for automobiles, industry and household appliances, due to the relatively large volume of coatings used. However, in addition to the requirement of low VOC content, many manufacturing products have very strict requirements in terms of the coatings used. For example, it is required that the transparent outer layers for automotive OEMs have a combination of good exterior durability, resistance to acid attack and water spots and excellent gloss and appearance. While liquid outer layers, in particular epoxy-acid cured liquid coatings, can provide These properties have the undesirable drawback of higher VOC levels in relation to powder coatings, which have essentially zero VOC levels. Epoxy-based powder coatings, such as epoxy-acid powder coatings, are known and have been developed for use in automotive, industrial and appliance applications. However, its use has been limited due to deficiencies in, for example, flow, appearance and storage stability. Epoxy-based powder coating compositions typically consist of a carboxylic-functional acid component, for example an acrylic copolymer prepared in part from (meth) acrylic acid, and an epoxy-functional component, for example an acrylic copolymer prepared in part from glycidyl methacrylate. The carboxylic-functional and epoxy-functional polymers used in said epoxy-acid cured powder coating compositions are typically prepared by standard polymerization methods, ie, non-living, radicals, which provide little control over molecular weight. , the distribution of molecular weights and the structure of the polymer chain. The physical properties, for example the temperature of The transition of the vitreous state (Tg) and the melt viscosity of a given polymer can be directly related to its molecular weight. The higher molecular weights are typically associated with, for example, Tg values and higher melt viscosities. The physical properties of a polymer having a broad molecular weight distribution, for example having a polydispersity index (IPD) above 2.0 or 2.5, can be characterized as an average of the individual physical properties of, and of the indeterminate interactions between, the various polymeric species that constitute it. As such, the physical properties of polymers having broad molecular weight distributions can be variable and difficult to control. The structure of the polymer chain, or the architecture, of a copolymer can be described as the sequence of monomeric residues along the backbone or chain of the polymer. For example, a copolymer containing functionality of reactive groups, for example oxirane or carboxylic acid functionality, prepared by standard techniques of radical polymerization will contain a mixture of polymer molecules having equivalent weights of variable individual reactive groups. Some of these polymer molecules can be really free of group functionality assets. In a thermosetting composition, the formation of a three-dimensional crosslinked network depends on the functional equivalent weight, as well as on the architecture of the individual polymeric molecules that constitute it. Polymer molecules that have little or no reactive functionality (or that have functional groups that are unlikely to participate in cross-linking reactions due to their location along the polymer chain) will contribute little or nothing to the formation of the network three-dimensional crosslinking, resulting in undesirable physical properties of the finally formed polymer, for example a cured or thermoset coating. The continuous development of new and improved epoxy-acid cured powder coating compositions having essentially zero levels of VOC and a combination of favorable performance properties is desirable. In particular, it would be desirable to develop epoxy-acid cured powder coating compositions containing carboxylic acid functional polymers and epoxy functional polymers, both with well-defined molecular weight and polymer chain structure and narrow molecular weight distributions, e.g. , IPD values less than 2.5. It is desirable to control the architecture and polydispersity of both the polymer functional carboxylic acid as the epoxy-functional polymer, in the sense that it allows to get higher Tg and melt viscosities lower than what is possible with comparable carboxylic acid polymers and epoxy polymers prepared by conventional procedures, giving rise to to thermosettable particulate compositions which are resistant to caking and which have better physical properties. International Patent Publication WO 97/18247 and US Patent Nos. 5,763,548 and 5,789,487 describe a radical polymerization process referred to as radical polymerization by atomic transfer (PRTA). PRTA is described as a living radical polymerization that results in the formation of (co) polymers having a predictable molecular weight and molecular weight distribution. It is also disclosed that the PRTA process provides highly uniform products with a controlled structure (ie controllable topology, composition, etc.). The patents "548 and 487 and patent publication WO 97/18247 also describe (co) polymers prepared by PRTA, which are useful in a wide variety of applications, for example in paints and coatings.

SUMMARY OF THE INVENTION According to the present invention, there is provided a thermosetting composition consisting of a solid particulate mixture that can be coactivated by: (a) polycarboxylic functional acid polymer prepared by radical polymerization by atomic transfer initiated in the presence of a first initiator having at least one a group transferable by radicals and wherein said polycarboxylic functional acid polymer contains at least one of the following polymer chain structures I and II: I - [(M1) t- (A) U] V and II where M1 is a residue, which is free of carboxylic acid functionality, of at least one ethylenically unsaturated radical polymerizable monomer; A is a residue, having carboxylic acid functionality, of at least one ethylenically unsaturated radical polymerizable monomer; t and u represent average numbers of the residues that appear in a block of residues in each polymer chain structure, and t, u and v are each independently selected for each structure, such that said functional polycarboxylic acid polymer has a number average molecular weight of at least 250; and (b) epoxy-functional polymer prepared by radical polymerization by atomic transfer initiated in the presence of a second initiator having at least one radical-transferable group and wherein said epoxy-functional polymer contains at least one of the following structures. polymer chain III and IV: III - [(M) p- (G) q] x and II -_ (G) q- (M) p _? - where M is a residue, which is free of oxirane functionality, of at least one ethylenically unsaturated radical polymerizable monomer; G is a residue, having oxirane functionality, of at least one ethylenically unsaturated radical polymerizable monomer; p and q represent average numbers of the residues that appear in a block of residues in each polymer chain structure, and p, q and x are each individually selected for each structure, such that said epoxy-functional polymer has a weight number average molecular weight of at least 250. According to the present invention, a method of coating a substrate with the above-described thermosetting composition is also provided. Also provided, according to the present invention, is a multi-component composite coating composition consisting of a base layer deposited from a pigmented film-forming composition and a transparent outer layer applied over the base layer. The outer transparent layer contains the thermosetting composition described above. Apart from in the operative examples, or where something different is indicated, all the numbers expressing quantities of components, reaction conditions, etc., used in the descriptive memory and in the claims have to be understood as modified in all the cases by the term "approximately". As used herein, the term "polymer" is intended to refer to both homopolymers, ie, polymers made from a single species of monomers, and copolymers, ie, polymers made from two or more species of monomers. DETAILED DESCRIPTION OF THE INVENTION The thermosetting compositions according to the present invention contain (a) one or more polycarboxylic acid functional polymers and (b) one or more epoxy functional polymers. As used herein and in the claims, by "polycarboxylic-functional acid polymer" and similar terms is meant a polymer having two or more carboxylic acid groups in terminal and / or pendant positions that are capable of reacting and forming bonds covalent with epoxide (or oxirane) groups. As used herein and in the claims, by "epoxy-functional polymer" is meant a polymer having two or more epoxy (or oxirane) groups in terminal and / or pendant positions that are capable of reacting and forming covalent bonds with groups containing reactive hydrogen, such as carboxylic acid groups. The carboxylic functional polymer and the epoxy functional polymer of the present invention are each independently prepared by radical polymerization by atomic transfer (PRTA). The PRTA method is described as a "living polymerization", that is, a chain growth polymerization that propagates essentially without chain transfer and essentially without chain termination. The molecular weight of a polymer prepared by PRTA can be controlled by the stoichiometry of the reagents, that is, the initial concentration of monomer (s) and initiator (s). In addition, the PRTA also provides polymers having characteristics which include, for example, narrow molecular weight distributions, for example IPD values less than 2.5, and well-defined polymer chain structure, for example block and block copolymers. alternating copolymers. The PRTA process can be described, in general, as consisting in: polymerizing one or more polymerizable monomers by radicals in the presence of an initiation system, forming a polymer and isolating the formed polymer. The initiation system consists of: an initiator that has an atom or group transferable by radicals; a transition metal compound, i.e., a catalyst, which participates in a reversible redox cycle with the initiator, and a ligand, which coordinates with the transition metal compound. The PRTA process is described in greater detail in the international patent publication WO 97/18247 and in US Patents No. 5,763,548 and No. 5,789,487. In preparing the carboxylic acid-functional polymers and the epoxy-functional polymers of the present invention, the first and the second initiator, respectively, are each one independently selected from the group consisting of linear or branched aliphatic compounds, cycloaliphatic compounds, aromatic compounds, polycyclic aromatic compounds, heterocyclic compounds, sulfonyl compounds, sulfenyl compounds, carboxylic acid esters, polymeric compounds and mixtures thereof, each having at least one radical-transferable group, which is typically a halo group. The initiators can also be substituted with functional groups, for example oxy-ranyl groups, such as glycidyl groups. Additional useful primers and the various radical-transferable groups that may be associated therewith are disclosed on pages 42 to 45 of the international patent publication WO 97/18247. Polymeric compounds (including oligomeric compounds) having radical-transferable groups can be used as first and second initiators and are referred to herein as "macroinitiators". Examples of macroinitiators include, but are not limited to, polyestyrene prepared by cationic polymerization and having a terminal halide, for example, chloride, and a polymer of 2- (2-bromopropionoxy) ethyl acrylate and one or more (meth) alkyl acrylates, for example butyl acrylate, prepared by conventional non-living radical limerization. Macroinitiators can be used in the PRTA process to prepare graft polymers, such as grafted block copolymers and comb copolymers. A larger discussion of macroinitiators can be found on pages 31 to 38 of the international patent publication WO 98/01480. Preferably, the first and second initiator can be selected from the group consisting of halomethane, methylene dihalide, haloform, carbon tetrahalide, 1-halo-2,3-epoxypropane, methanesulfonyl halide, p-toluenesulfonyl halide, halide methanesulfenyl, p-toluenesulfenyl halide, 1-phenylethyl halide, Ci-Cs alkyl ester of 2-halocarboxylic acid C _.- C6, p-halomethylstyrene, mo-nohexakis (-haloalkyl-C? -C6) benzene, malonate of diethyl-2-halo-2-methyl, ethyl 2-bromoisobutyrate and their mixtures. A particularly preferred initiator is diethyl-2-bromo-2-methyl malonate. Catalysts that can be used in the preparation of carboxylic acid functional polymers and epoxy functional polymers of the present invention include any transition metal compound that can participate in a redox cycle with the initiator and the polymer chain in growth . It is preferred that the metal- Transition co does not form direct carbon-metal bonds with the polymer chain. The transition metal catalysts useful in the present invention can be represented by the following general formula V: V MTn + X__ where MT is the transition metal, n is the formal charge on the transition metal and has a value of 0 to 7 and X is a counterion or covalently linked component. Examples of the transition metal (MT) include, but are not limited to, Cu, Fe, Au, Ag, Hg, Pd, Pt, Co, Mn, Ru, Mo, Nb, and Zn. Examples of X include, but are not limited to, halogen, hydroxy, oxygen, C 1 -C 6 alkoxy, cyano, cyanate, thiocyanate and azido. A preferred transition metal is Cu (I) and X is preferably halogen, for example chloride. Accordingly, a preferred class of transition metal catalysts are copper halides, for example Cu (I) Cl. It is also preferred that the transition metal catalyst contains a small amount, for example 1 mole percent, of a redox conjugate, for example Cu (II) Cl2 when Cu (I) Cl is used. Additional catalysts useful in the preparation of the polymers of the present invention are described on pages 45 and 46 of WO International Patent Publication. 97/18247. On pages 27 to 33 of the international patent publication WO 97/18247, redox conjugates are described. Ligands that can be used in the preparation of carboxylic acid-functional polymers and epoxy-functional polymers of the present invention include, but are not limited to, compounds having one or more nitrogen, oxygen, phosphorus and nitrogen atoms. / or sulfur, which can be coordinated with the transition metal catalyst compound, for example through sigma and / or pi bonds. Suitable claylike classes include, but are not limited to: unsubstituted and substituted pyridines and bipyridines; por-firinas; cryptandos; crown ethers, for example 18-crown-6; polyamines, for example ethylene diamine; glycols, for example alkylene glycols, such as ethylene glycol; carbon monoxide, and coordinating monomers, for example styrene, acrylonitrile and hydroxyalkyl (meth) acrylates. A preferred class of ligands are the substituted bipyridines, for example 4,4'-dialkyl bipyridyls. Additional ligands that can be used in the preparation of polymers of the present invention are described on pages 46 to 53 of the international patent publication WO 97/18247. In preparing the carboxylic acid-functional polymers and the epoxy-functional polymers of the present invention, the relative amounts and proportions of initiator, transition metal compound and ligand are those for which the PRTA is carried out with the greatest effectiveness. The amount of initiator used can vary widely and is typically present in the reaction medium in a concentration of 10 ~ 4 moles / liter (M) to 3 M, for example 10"3 M to 10'1 M. As the weight The molecular weight of the polymers can be directly related to the relative concentrations of initiator and monomer (s), the molar ratio of initiator to monomer is an important factor in the preparation of polymers.The molar ratio of initiator to monomer is typically in the range from 10 ~ 4: 1 to 0.5: 1, for example, from 10"3: 1 to 5x10" 2: 1. In preparing the carboxylic acid-functional polymers and the epoxy-functional polymers of the present invention, the mole ratio of transition metal compound to initiator is typically in the range of 10"4: 1 to 10: 1, eg, 0.1: 1 to 5: 1. The molar ratio of ligand to transition metal compound is typically in the range of 0.1: 1 to 100: 1, for example, 0.2: 1 to 10: 1. The carboxylic acid functional polymers and the epoxy functional polymers useful in the thermosetting compositions of the present invention may each be prepared in the absence of solvent, i.e., by means of a mass polymerization process. In general, the carboxylic acid functional polymer and the epoxy functional polymer are each prepared separately in the presence of a solvent, typically water and / or an organic solvent. Suitable classes of organic solvents include, but are not limited to, esters of carboxylic acids, ethers, cyclic ethers, C5-C_.0 alkanes, C5-C8 cycloalkanes, aromatic hydrocarbon solvents, halogenated hydrocarbon solvents, amides, nitriles, sulfoxides. , sulfones and their mixtures. It is also possible to use supercritical solvents, such as C02, C __-C4 alkanes and fluorocarbons. A preferred class of solvents are aromatic hydrocarbon solvents, with particularly preferred examples being xylene and mixed aromatic solvents, such as those marketed by Exxon Chemical America under the trademark SOLVESSO. Additional solvents are described in greater detail on pages 53 to 56 of the international patent publication WO 97/18247. Due to the possible deactivation of some PRTA catalysts, for example copper, in the presence of carboxylic acid groups, the PRTA process described above is generally carried out in substantial absence of carboxylic acid functionality. Consequently, the acidic polymer The functional-boxyl (a) used in the composition of the present invention is typically prepared in two stages. The first step involves the preparation by PRTA of a precursor of the functional polycarboxylic acid polymer that is substantially free of carboxylic acid functionality ("precursor polymer"). In the second step, the precursor polymer is converted to the functional polycarboxylic acid polymer (a) of the composition of the present invention. In contrast, since the epoxy-functional polymer (b) of the present invention typically does not contain carboxylic acid groups, it is generally prepared in a single step, ie, that the preparation of a precursor for the epoxy-functional polymer is not, in general, necessary. The conversion of the precursor polymer into the polycarboxylic-functional acid polymer is carried out using methods known to those of ordinary skill in the art. Such known methods of conversion include, but are not limited to: (a) hydrolyzing residues of alkyl (meth) acrylate monomers, for example t-butyl methacrylate, present in the backbone of the precursor polymer and (b) reaction of the residues of the radically polymerizable, ethylenically unsaturated, hydroxy-functional monomers present in the backbone of the precursor polymer, for example hydroxyethyl methacrylate, with cyclic anhydrides, for example succinic anhydride. The epoxy-functional polymer and the precursor polymer of the carboxylic acid functional polymer are each typically prepared at a reaction temperature in the range of 25 ° C to 140 ° C, for example 50 ° C to 100 ° C, and a pressure in the range of 1 to 100 atmospheres, normally at ambient pressure. Radical polymerization by atomic transfer is typically completed in less than 24 hours, for example, between 1 and 8 hours. When preparing the carboxylic acid functional polymer and the epoxy functional polymer each in the presence of a solvent, the solvent is removed after each of the polymers has been formed by appropriate means known to those of ordinary skill in the art. technique, for example vacuum distillation. Alternatively, the polymer can be precipitated from the solvent, filtered, washed and dried according to known methods. After removal of the solvent or separation therefrom, the carboxylic acid functional polymer and the epoxy functional polymer each typically have a solids content (measured by placing a 1 gram sample in a oven at 110 ° C for 60 minutes) of at least one 95 percent and, preferably, at least 98 percent by weight, based on the total weight of the polymer. Prior to use in the thermosetting compositions of the present invention, the PRTA transition metal catalyst and its associated ligand are typically separated or removed from the polymer. In the case of the carboxylic acid functional polymer (a), the PRTA catalyst is preferably removed before the conversion of the precursor polymer into the carboxylic acid functional polymer. The removal of the PRTA catalyst is achieved using known methods, including, for example, the addition of a catalyst binding agent to a mixture of the polymer, solvent and catalyst, followed by filtration. Examples of suitable catalyst binding agents include, for example, alumina, silica, clay or a combination thereof. A mixture of the polymer, the solvent and the PRTA catalyst can be passed through a bed of catalyst binding agent. Alternatively, the PRTA catalyst can be oxidized in situ and retained in the precursor polymer. The carboxylic acid functional polymer (a) and the epoxy functional polymer (b) can each be independently selected from the group consisting of linear polymers. branched polymers, hyperbranched polymers, star polymers, graft polymers and mixtures thereof. The shape, or coarse architecture, of the polymer can be controlled by choosing the initiator and the monomers used in its preparation. Linear polymers can be prepared using initiators having one or two radical-transferable groups, for example diethyl-2-halo-2-methyl malonate and, -dichloroxylene. Branched polymers can be prepared using branching monomers, ie, monomers containing radical-transferable groups or more than one ethylenically unsaturated radical-polymerizable group, for example 2- (2-bromopropionoxy) ethyl acrylate, p-chloromethylstyrene and bis (meta) -crylate) of diethylene glycol. Hyperbranched polymers can be prepared by increasing the amount of branching monomer used. Star-functional carboxylic acid polymers and star-functional epoxy polymers can be prepared using initiators having three or more radical-transferable groups, for example hexakis (bromomethyl) benzene. As is known to those of ordinary skill in the art, star polymers can be prepared by core-arm or arm-core methods. In the core-arm method, the star polymer is prepared by polymerizing monomers in presence of the polyfunctional initiator, for example hexa-kis (bromomethyl) benzene. Polymer chains, or arms, of similar composition and architecture grow outward from the initiator core in the core-arm method. In the arm-core method, the arms are prepared separately from the nucleus and may eventually have different composition, architecture, molecular weight and IPD. The arms can have different equivalent weights of functional groups and some can be prepared without any reactive functionality. After the preparation of the arms, they are attached to the core. In the case of the carboxylic acid functional polymer (a), and for illustrative purposes, the arms (in the form of precursor polymers) can be prepared by PRTA using, for example, epoxide-functional initiators. These arms can then be attached to a core having three or more active hydrogen groups that are reactive with epoxides, for example carboxylic or hydroxyl groups. After attachment to the core, the precursor polymers of the arms can then be converted into carboxylic-functional acid arms, as described hereinabove. The nucleus can be a molecule, such as citric acid, or a star-core polymer-arm prepared by PRTA and having groups that contain reactive hydrogen terminals, for example carboxylic acid, thiol or hydroxyl groups. An example of a core prepared by PRTA methods that can be used as a core in a carboxylic acid-functional arm-core polymer star PRTA is described as follows. In the first step, 6 moles of methyl methacrylate are polymerized in the presence of one mole of 1,3,5-tris (bromomethyl) benzene. In the second step, 3 moles of 2-hydroxyethyl methacrylate are fed into the reaction mixture. The core having terminal residues of 2-hydroxyethyl methacrylate is isolated and then reacted in the third step with a cyclic anhydride, such as succinic anhydride. In the final stage, three precursor polymer arms prepared by PRTA of variable composition or equivalent and each containing oxirane-functional initiator residues are connected to the carboxylic acid-terminated core by reaction between the carboxylic acid groups of the core and the epoxy functionality. of the arms. The precursor polymers of the arms are then converted into carboxylic-functional acid arms. Functional carboxylic acid polymers and epoxy functional polymers can be prepared each in the form of graft polymers using a macroinitiator, as described here previously. Graft polymers, branched, hyperbranched and star are described in greater detail on pages 79 to 91 of the international patent publication WO 97/18247. The polydispersity index (IPD) of the carboxylic acid functional polymers and of the epoxy functional polymers useful in the present invention is typically less than 2.5, more typically less than 2.0, and preferably less than 1.8. , for example 1.5. As used herein and in the claims, the "polydispersity index" is determined by the following equation: (weight average molecular weight (Mp) / number average molecular weight (Mn)). A monodisperse polymer has an IPD of 1.0. In addition, as used herein, Mn and Mp are determined by gel permeation chromatography using polystyrene standards. The general polymeric chain structures I and II represent, together or separately, one or more structures that constitute the architecture of the polymer chain, or backbone, of the carboxylic acid functional polymer (a). The sub-indices t and u of the general polymeric chain structures I and II represent the average numbers of residues that appear in the waste blocks M1 and A, respectively. The subscript v represents the number of segments of the bio- M1 and A, that is, v-segments. The subscripts t and u may each be the same or different for each v-segment. Similarly, the general polymer chain structures III and IV represent, together or separately, one or more structures that constitute the architecture of the polymer chain, or skeleton, of the epoxy-functional polymer (b). The subscripts p and q of the general structures of polymer chains III and IV represent the average numbers of residues that appear in the waste blocks M and G, respectively. The subscript x represents the number of segments of blocks M and G, that is, x-segments. The subscripts p and q may each be the same or different for each x-segment. In order to illustrate the various polymeric architectures that are represented by the above general polymeric chain structures, the following is presented with specific reference to the general polymeric chain structures III and IV. Polyblock polymer architecture: When it is l, p is 0 q is 5, the general structure of polymer chain III represents a homoblock of 5 residues G, as is more specifically represented by the following general formula V.

V - (G) - (G) - (G) - (G) - (G) - Architecture of diblock copolymer: When x is 1, p is 5 and q is 5, the general structure of polymer chain III represents a diblock of 5 residues M and 5 residues G, as is more specifically represented by the following general formula VI. VI - (M) - (M) - (M) - (M) - (M) - (G) - (G) - (G) - (G) - (G) - Alternating copolymer architecture: When x is greater than 1, for example 5, and p and q are each 1 for each x segments, the polymer chain structure III represents an alternating block of residues M and G, as more specifically represented by the following general formula VII.

VII - (M) - (G) - (M) - (G) - (M) - (G) - (M) - (G) - (M) - (G) - Gradient copolymer architecture: When x is greater than 1, for example 3, and p and q are each independently in the range of, for example, 1 to 3, for each x segments, the polymer chain structure III represents a block in gradient of residues M and G, as it is more specifically represented by the following general formula VIII. VIII - (M) - (M) - (M) - (G) - (M) - (M) - (G) - (G) - (M) - (G) - (G) - (G) - The gradient copolymers can be prepared from two or more monomers by PRTA methods and are generally described as having an architecture that changes gradually and in a systematic and predictable manner along the polymer backbone. The gradient copolymers can be prepared by PRTA methods (a) by varying the ratio of monomers fed into the reaction medium in the course of the polymerization, (b) using a monomer feed containing monomers with different polymerization rates or (c) with a combination of (a) and (b). The gradient copolymers are described in greater detail on pages 72 to 78 of the international patent publication WO 97/18247. Still referring to the general polymer chain structures III and IV, M represents one or more types of residues that are free of oxirane functionality and p represents the average total number of M residues that appear per block of M residues (M block) in x segments. The - (M) p- portion of the general structures III and IV represents (1) a homoblock of a single type of waste M, (2) an alternating block of two types of waste M, (3) a polyblock of two or more types of waste M or (4) a block in gradient of two or more types of waste M. For illustrative purposes, when block M is prepared from, for example, 10 moles of methyl methacrylate, the - (M) p- portion of structures III and IV represents a homoblock of 10 residues of methyl methacrylate. . In case block M is prepared from, for example, 5 moles of methyl methacrylate and 5 moles of butyl methacrylate, the - (M) p- portion of the general structures III and IV represents, depending on the preparation conditions, as is known to one of ordinary skill in the art: (a) a diblock of 5 residues of methyl methacrylate and 5 residues of butyl methacrylate having a total of 10 residues (ie, p = 10); (b) a diblock of 5 residues of butyl methacrylate and 5 residues of methyl methacrylate having a total of 10 residues; (c) an alternating block of residues of methyl methacrylate and butyl methacrylate starting with a residue of methyl methacrylate or with a residue of butyl methacrylate and having a total of 10 residues; or (d) a gradient block of methyl methacrylate and butyl methacrylate residues that starts with methyl methacrylate residues or with butyl methacrylate residues and has a total of 10 residues. Furthermore, in relation to the general polymer chain structures III and IV, G represents one or more types of residues having oxirane functionality and q represents the average total number of G residues that appear per block of residues G (block G) in x-segments. Accordingly, the portions - (G) q- of the polymer chain structures III and IV can be described in a manner similar to that of the - (M) p- portions noted above. With respect to the general polymeric chain structures I and II, M1 represents one or more types of residues that are free of carboxylic acid functionality and t represents the average total number of M1 residues that appear per block of M1 residues (M1 block) in v-segments. The symbol A of the general formulas I and II represents one or more types of residues having carboxylic acid functionality and u represents the total average number of A residues that appear per block of residues A (block A) in a v-segment. The portions - (M1) - and - (A) u- of the polymer chain structures I and II can be described, in general, in a manner similar to that of the portions - (M) p- and (G) ) of the polymer chain structures III and IV as shown here above.

The residue M of the general polymeric chain structures I and II and the residue M1 of the general polymer chain structures III and IV each independently derive from at least one ethylenically unsaturated, radically polymerizable monomer. As used herein and in the claims, "radically polymerizable ethylenically unsaturated monomer" and similar terms are intended to include vinyl monomers, allylic monomers, olefins and other ethylenically unsaturated monomers that are radically polymerizable. The classes of vinyl monomers from which M and M1 can be derived each independently include, but are not limited to, (meth) acrylates, vinyl aromatic monomers, vinyl halides and vinyl esters of carboxylic acids. As used herein and in the claims, both methacrylates and acrylates are referred to by the terms "(meth) acrylate" and the like. Preferably, the residues M and M1 each independently derive from at least one of alkyl (meth) acrylates having from 1 to 20 carbon atoms in the alkyl group. As specific examples of alkyl (meth) acrylates having from 1 to 20 carbon atoms in the alkyl group from which residues M and M1 can derive independently from each other include, but are not limited to, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, isopropyl (meth) acrylate, butyl (meth) acrylate, isobutyl (meth) acrylate, tere-butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, lauryl (meth) acrylate, isobornyl (meth) acrylate, cyclohexyl (meth) acrylate and 3, 3, 5- (meth) acrylate trimethylcyclohexyl. The residues M and M1 may also each independently be selected from monomers having more than one (meth) acrylate group, for example (meth) acrylic anhydride and diethylene glycol bis (meth) acrylate. The M and M1 residues can also each be independently selected from alkyl (meth) acrylates containing radical-transferable groups, which can act as branching monomers, for example 2- (2-bromopropionoxy) ethyl acrylate. Specific examples of vinyl aromatic monomers from which M and M1 can be derived each independently include, but are not limited to, styrene, p-chloromethylstyrene, divinylbenzene, vinylnaphthalene and divinyl-naphthalene. The vinyl halides from which M and M1 can be derived each independently include, but are not limited to, vinyl chloride and vinylidene fluoride. The vinyl esters of carboxylic acids from which M can be derived and M1 each independently include, but are not limited to, vinyl acetate, vinyl butyrate, vinyl 3,4-dimethoxybenzoate and vinyl benzoate. As used herein and in the claims, by "olefin" and similar terms reference is made to unsaturated aliphatic hydrocarbons having one or more double bonds, such as those obtained by fractionation of petroleum fractions. As specific examples of olefins from which M and M1 can be derived each independently include, but are not limited to, propylene, 1-butene, 1,3-butadiene, isobutylene and diisobutylene. As used herein and in the claims, by "allylic monomer (s)" reference is made to monomers containing substituted and / or unsubstituted allylic functionality, i.e., one or more radicals represented by the following general formula IX, IX H2C = C (R4) -CH2- where R4 is hydrogen, halogen or a Ci to C4 alkyl group. Most commonly, R 4 is hydrogen or methyl and, consequently, general formula IX represents the unsubstituted (meth) allyl radical. Examples of allylic monomers include, but are not limited to: (meth) allyl alcohol; ethers (meth) allylic, such as methyl (meth) allyl ether; allyl esters of carboxylic acids, such as (meth) allyl acetate, (meth) allyl butyrate, (meth) allyl 3,4-dimethoxybenzoate and (meth) allyl benzoate. Other radically polymerizable ethylenically unsaturated monomers from which M and M1 can be independently derived include, but are not limited to: cyclic anhydrides, for example maleic anhydride, 1-cyclopentene-1,2-dicarboxylic anhydride and itaconic anhydride; esters of acids which are unsaturated, but which do not have unsaturation, ethylene, for example undecylic acid methyl ester, and diesters of ethylenically unsaturated dibasic acids, for example diethyl maleate. The residue A of the general polymeric chain structures I and II typically derives from alkyl (meth) acrylate, which, after polymerization, is hydrolyzed; or at least one radically polymerizable hydroxy-functional unsaturated monomer which, after polymerization, post-reacts with a cyclic anhydride. Examples of suitable hydroxy-functional ethylenically unsaturated and radical polymerizable classes of monomers from which residue A can be derived include, but are not limited to: vinyl esters, such as vinyl acetate, which are hydrolyzed to vinyl alcohol residues after polymerization; allyl esters, such as allyl acetate, which are hydrolyzed to allyl alcohol residues after polymerization; allylic functional monomers which also have hydroxy functionality, for example allyl alcohol and 2-allylphenol; vinyl aromatic monomers having hydroxy functionality, for example 2-ethenyl-5-methylphenol, 2-ethenyl-6-methylphenol and 4-ethenyl-3-methylphenol, and hydroxy-functional (meth) acrylates, such as (meth) acrylates of hydroxyalkyl, for example hydroxyethyl (meth) acrylate and hydroxypropyl (meth) acrylate. The cyclic anhydride is selected from those that can react with residues of the hydroxy-functional, ethylenically unsaturated monomer radically polymerizable in the backbone of the precursor polymer, thus binding the carboxylic acid groups thereto. Examples of suitable cyclic anhydrides include, but are not limited to, succinic anhydride, maleic anhydride, glutaric anhydride, adipic anhydride, and pimelic anhydride. In a preferred embodiment of the present invention, the residue A is derived from: C 1 -C 4 alkyl (meth) acrylate, for example t-butyl methacrylate, which is hydrolyzed after the polymerization; or at least one of hydroxyethyl (meth) acrylate tyl and hydroxypropyl (meth) acrylate, which post-react, after polymerization, with a cyclic compound, for example succinic anhydride. The residue A can also be derived from other monomers which can be converted or still react with other compounds to obtain acid functionality after completion of the PRTA polymerization process. Examples of such other monomers from which residue G may be derived include, but are not limited to: acrylonitrile, the portion of nitrile from which it may be hydrolyzed to a carboxylic acid group after polymerization; isocyanate-functional monomers, for example 3-isopropenyl-, -dimethylbenzyl isocyanate [registration number in Chemical Abstracts (CAS) 2094-99-7], which can react after polymerization with compounds containing functionality both of carboxylic acid as well as hydroxyl, for example 12-hydroxystearic acid and lactic acid, and maleic anhydride, which, after polymerization, can be hydrolyzed to form carboxylic acid groups or reacted with a monofunctional alcohol in the presence of acid catalyst to form groups ester and carboxylic acid. The choice of monomers from which each of the residues M1 and A can be selected is interrelated. nothing, that is, that the choice of the monomers from which A is derived limits the choice of the monomers from which M1 is derived. When the residue A is derived from radically polymerizable hydroxy functional (s) ethylenically unsaturated monomer (s), which, after polymerization, post-reacts with a cyclic anhydride, the M1 residue typically does not derived from said monomer (s). In addition, when the residue A is derived from one or more alkyl (meth) acrylates, which, after polymerization, are hydrolyzed, the M1 residue typically does not derive from said monomers. The residue G of the general polymer chain structures III and IV typically derives from monomers having epoxy functionality. Preferably, the residue G is derived from at least one of glycidyl (meth) acrylate, 3,4-epoxycyclohexylmethyl (meth) acrylate, 2- (3,4-epoxycyclohexyl) ethyl (meth) acrylate and allyl glycidyl ether. In a particularly preferred embodiment of the present invention, the residue g is derived from glycidyl methacrylate. Alternatively, the epoxy functionality can be incorporated into the epoxy-functional polymer by post-reaction, such as by preparation of a hydroxyl-functional polymer and conversion to an epoxy-functional polymer by reaction with epichlorohydrin. The subscripts t and u represent the average number of re- wastes that appear in a block of waste in each of the polymeric structures I and II. Typically, t and u each independently have a value of 0 or more, preferably at least 1 and, more preferably, at least 5 for each of the polymeric general structures I and II. In addition, the subscripts t and u each independently have a value typically less than 100, preferably less than 20 and, more preferably, less than 15 for each of the general polymeric structures I and II. The values of the subscripts t and u can vary between any combination of these values, including the indicated values. Moreover, the sum of t and u is at least 1 in a v-segment and q is at least 1 in at least one v-segment in the carboxylic acid functional polymer. The subscript v of the polymeric general structures I and II typically has a value of at least 1. In addition, the subscript v typically has a value less than 100, preferably less than 50, and more preferably less than 10. The value of the subscript v can vary between any combination of these values, including the indicated values. If more than one of the structures I and / or II appear in the polymer carboxylic acid functional, v can have different values for each structure (like t and u), allowing a variety of polymeric architectures, such as gradient copolymers. The subscripts p and q represent the average number of residues that appear in a block of residues in each of the general polymer chain structures III and IV. Typically, p and q each independently have a value of 0 or more, preferably of at least 1 and, more preferably of at least 5, for each of the general polymer structures III and IV. In addition, the subscripts p and q each independently have a value typically less than 100, preferably less than 20, and more preferably less than 15 for each of the general polymer structures III and IV. The values of the subscripts p and q may vary between any combination of these values, including the indicated values. Moreover, the sum of p and q is at least 1 in an x-segment and q is at least 1 in at least one x-segment in the epoxy-functional polymer. The subscript x of the polymeric general structures III and IV typically has a value of at least 1. In addition, the subscript x typically has a value of less than 100, preferably less than 50, and more preferably less than 10. The value of the subscript x may vary between any combination of these values, including the indicated values. Yes more than one of structures III and / or IV appear in the epoxy-functional polymer molecule, x may have different values for each structure (as well as p and q), allowing a variety of polymeric architectures, such as gradient copolymers. The polycarboxylic acid functional polymer (a) of the present invention can be further described as having at least one of the following general polymer chain structures X and XI: X f1 - [[(M1) t- (A) u] v- (M1) j-T1] 1 and XI f1 - [[(A) u- (M1) t] v- (A) k-T1] 1 where t, u, v, M1 and A have the same meanings as those previously described here. The subscripts j and k represent the average numbers of residues that appear in the respective waste blocks M1 and A. The portions - (M1) j- and - (A) u-of the general formulas X and XI have meanings similar to those previously reported here described with respect to the portions - (M1) t- and - (A) u-. The epoxy-functional polymer (b) of the present invention it may further be described as having at least one of the following general polymeric chain structures XII and XIII: XII f2 - [[(M) p- (G) g] x- (M) r-T2_z and XIII f2 - [[(G) q- (M) p_x- (G) 8-T2] z where p, q, x, M and G have the same meanings as those previously described here. The subscripts r and s represent the average numbers of residues that appear in the respective waste blocks M and G. The portions - (M) r- and - (G) s - of the general formulas XII and XIII have meanings similar to those previously reported here described with respect to the portions - (M) p- and - (G) q-. The structures X, XI, XII and XIII may represent the respective polymers themselves or, alternatively, each of the structures may contain a terminal segment of the respective polymers. For example, when z is 1, structures XII and XIII may represent a linear polymer, prepared by PRTA using an initiator having 1 group transferable by radicals. When z is 2, structures XII and XIII can represent a linear "leg" that is ex- tends from an initiator that has 2 groups transferable by radicals. Alternatively, when z is greater than 2, structures XII and XIII can each represent an "arm" of a star polymer prepared by PRTA, using an initiator having at least 2 groups transferable by radicals. The general polymeric chain structures X and XI can be described similarly with respect to the associated subscript 1. The symbols f1 and f2 of the general formulas X, XI, XII and XIII are each independently, or derive each independently, respectively , of, the residues of the first and second initiator used in the PRTA preparation of the respective polymers. The symbols f1 and f2 are also described as being the same or different and each being free of the group transferable by radicals of the respective first and second initiator. For example, when an epoxy-functional polymer is initiated in the presence of benzyl bromide, the symbol f2, more specifically f2-, is the benzyl residue, The symbols f1 and f2 of the general formulas X, XI, XII and XIII can also each independently derive the residue of the respective first and second initiator. For example, when the epoxy-functional polymer is initiated using epichlorohydrin, the symbol f2, more specifically f2-, is the 2,3-epoxypropyl residue, The 2.3-epoxypropyl residue can then be converted into, for example, a 2,3-dihydroxypropyl residue. In the general formulas X and XI, the subscript 1 is equal to the number of functional carboxylic acid polymer chains that are linked to f1. In general formulas XII and XIII, the subscript z is equal to the number of epoxy-functional polymer chains that are attached to f2. The subscripts 1 and z are each independently at least 1 and can have a wide range of values. In the case of comb or graft polymers, where f1 and f2 can each be macroinitiators having several radical transferable groups, 1 and z can each have independently a value above 10, for example 50, 100 or 1,000. Typically, 1 and z are each independently less than 10, preferably less than 6 and, more preferably, less than 5. In a preferred embodiment of the present invention, 1 and z are each independently 1 or 2. The symbols T1 and T2 of the general formulas X, XI, XII and XIII are each independently, or derive each independently of, the group transferable by radicals of the respective first and second initiator. For example, when the epoxy-functional polymer is prepared in the presence of diethyl-2-bromo-2-methyl malonate, T2 may be the bromine group transferable by radicals. The groups transferable by radicals of the first and second initiator may eventually be (a) eliminated or (b) chemically converted into another residue. In (a) or in (b), the symbols T1 and T2 are here considered as derivatives of the group transferable by radicals of the respective first and second initiator. The group which can be transferred by radicals can be removed by substitution with a nucleophilic compound, for example an alkali metal alkoxylate. However, in the present invention, it is desirable that the method by which the radical-transferable group is chemically removed or chemically converted is also relatively smooth with respect to pecto to the epoxy functionality of the polymer. In a preferred embodiment of the present invention, when the radical-transferable group is a halogen (correspondingly, T1 and T2 are each independently halide), the halogen can be removed by means of a mild dehalogenation reaction. The reaction is typically carried out as a post-reaction after the polymer has been formed and in the presence of at least one PRTA catalyst. Preferably, the posthalogenation reaction is carried out in the presence of both a PRTA catalyst and its associated ligand. In the case of the functional polycarboxylic acid polymer, the posthalogenation reaction is further preferably carried out with the precursor polymer, before its conversion into the carboxylic acid functional polymer. The gentle dehalogenation reaction is carried out by contacting the halogen-terminated polymers of the present invention with one or more ethylenically unsaturated compounds, which are not readily polymerizable by radicals in at least a portion of the spectrum of conditions under which they are carried out. Radical polymerizations by atomic transfer, which will be referred to hereinafter as "ethylenically bound compounds" Radical polymerizable saturates "(LEIPR compound) As used herein," halogen-terminated "and similar terms are also intended to include pendant halogens, for example as they would be present in branched, comb and star polymers. some, we believe, based on the evidence that is available, that the reaction between the halogen-finished polymer and one or more LEIPR compounds results in (1) the elimination of the halogenated terminoal group and (2) the addition of at least one carbon-carbon double bond where the carbon-halogen terminal bond has been broken The dehalogenation reaction is typically conducted at a temperature in the range of 0 ° C to 200 ° C, for example 0 ° C to 160 ° C. ° C, and at a pressure in the range of 0.1 to 100 atmospheres, for example 0.1 to 50 atmospheres.The reaction is also typically carried out in less than 24 hours, for example between 1 and 8 hours. that the LEI compound PR can be added in less than a stoichiometric amount, it is preferably added in at least a stoichiometric amount relative to the moles of the terminal halogen present in the polymer. When added in excess of a stoichiometric amount, the LEIPR compound is typically present in an amount not greater than 5 mole percent, for example 1 at 3 mole percent, in excess of the total moles of terminal halogen. Among the limited radically polymerizable ethylenically unsaturated compounds useful for the dehalogenation of each of the carboxylic functional polymer and the epoxy functional polymer of the composition of the present invention under mild conditions are those represented by the following general formula XIV. XIV R3 Ri R3 R2 In the general formula XIV, R and R2 can be identical or different organic groups, such as: alkyl groups of 1 to 4 carbon atoms, aryl groups, alkoxy groups, ester groups, alkyl sulfur groups, acyloxy groups and alkyl groups containing nitrogen, where at least one of the groups Rx and R2 is an organic group, while the other may be an organic group or hydrogen. For example, when one of R_. or R2 is an alkyl group, the other can be an alkyl, aryl, acyloxy, alkoxy, arene, sulfur-containing alkyl or nitrogen-containing and / or aryl-containing nitrogen-containing alkyl groups. The R3 groups can be the same or different groups selected from hydrogen or lower alkyl selected in such a way that the reaction between the terminal halogen of the polymer and the LEIPR compound is not avoided. In addition, a group R3 can join the groups R_. and / or R2 to form a cyclic compound. It is preferred that the LEIPR compound be free of halogen groups. Examples of suitable LEIPR compounds include, but without limitation, 1, 1-dimethylethylene, 1,1-diphenylethylene, isopropenyl acetate, alpha-methylstyrene, 1,1-dialkoxyolefin and mixtures thereof. Further examples include dimethyl itaconate and diisobutene (2,4,4-trimethyl-1-pentene). For purposes of illustration, the reaction between a halogen-terminated polymer and a LEIPR compound, for example alpha-methylstyrene, is summarized in the following general scheme 1. General scheme 1 In the general scheme 1, P-X represents the polymer finished in halogen. For each of the general polymer structures X and XI, the subscripts j and k each independently have a value of 0 or more. The subscripts j and k each independently have a value typically less than 100, preferably less than 50, and more preferably less than 10, for each of the general polymer structures X and XI. The values of j and k can each vary between any combination of these values, including the indicated values. For each of the general polymeric structures XII and XIII, the subscripts r and s each independently have a value of 0 or more. The subscripts r and s each independently have a value typically less than 100, preferably less than 50 and, more preferably, less than 10 for each of the general polymeric structures XII and XIII. The values of r and s can each vary between any combination of these values, including the values indicated. The functional polycarboxylic acid polymer (a) typically has an equivalent carboxylic acid weight of at least 100 grams / equivalent and, preferably, at least 200 grams / equivalent. The carboxylic acid equivalent weight of the polymer is also typically less than 10,000 grams / equivalent, preferably less than 5,000 grams / equivalent and, more preferably, less than 1,000 grams / equivalent. The carboxylic acid equivalent weight of the polycarboxylic acid functional polymer can vary between any combination of these values, including the indicated values. The number average molecular weight (Mn) of the polycarboxylic functional acid polymer is typically at least 250, more typically at least 500, preferably at least 1,000, and more preferably at least 2,000. The carboxylic acid functional polymer also typically has an Mn of less than 16,000, preferably less than 10,000 and, more preferably, less than 5,000. The Mn of the carboxylic acid functional polymer can vary between any combination of these values, including the indicated values. The epoxy-functional polymer (b) typically has an epoxy equivalent weight of at least 100 grams / equivalent and, preferably, at least 200 grams / equivalent. The epoxy equivalent weight of the polymer is also typically less than 10,000 grams / equivalent, preferably less than 5,000 grams / -equivalent and, more preferably, less than 1,000 grams / equivalent. The epoxy equivalent weight of the epoxy-functional polymer can vary between any combination of these values, including the indicated values. The number average molecular weight (Mn) of the epoxy functional polymer is typically at least 250, more typically at least 500, preferably at least 1,000, and more preferably at least 2,000. The epoxy functional polymer also typically has an Mn of less than 16,000, preferably less than 10,000 and, more preferably, less than 5,000. The Mn of the epoxy-functional polymer may vary among any combination of these values, including the indicated values. The polycarboxylic-functional acid polymer and the epoxy-functional polymer can each be used in the thermosetting composition of the present invention as resinous binders or as additives with separate resinous binders, which can be prepared by PRTA or by conventional polymerization methods. When used as additives, the polycarboxylic-functional acid polymer and the epoxy-functional polymer described herein typically have low functionality; for example, they can each be monofunctional and with a correspondingly high equivalent weight. The functional polycarboxylic acid polymer (a) is typically present in the thermosetting composition of the present invention in an amount of at least 0.5 percent by weight, more typically at least 5 percent by weight, more preferably, at least 30 percent by weight and, more preferably, at least 40 percent by weight, based on the total weight of the resin solids of the thermosetting composition. The thermosetting composition also typically contains polycarboxylic acid functional polymer present in an amount of less than 99.5 weight percent, more typically less than 95 weight percent, preferably less than 70 weight percent, and more preferably, less than 50 percent by weight, based on the total weight of the resin solids of the thermosetting composition. The polycarboxylic-functional acid polymer may be present in the thermosetting composition of the present invention in an amount in a range between any combination of these values, including the indicated values. The epoxy-functional polymer (b) is typically present in the thermosetting composition of the present invention. in an amount of at least 0.5 percent by weight, more typically at least 5 percent by weight, preferably at least 30 percent by weight and, more preferably at least 40 percent by weight, in based on the total weight of resin solids of the thermosetting composition. The thermosetting composition also typically contains epoxy-functional polymer present in an amount of less than 99.5 weight percent, more typically less than 95 weight percent, preferably less than 70 weight percent, and more preferably , less than 50 weight percent, based on the total weight of resin solids of the thermosetting composition. The epoxy-functional polymer may be present in the thermosetting composition of the present invention in an amount in a range between any combination of these values, including the indicated values. The thermosetting composition of the present invention may optionally also contain a second functional polycarboxylic acid material. Suitable classes of second functional polycarboxylic acid materials include, but are not limited to, C4 to C2o aliphatic dicarboxylic acids, polymeric polyanhydrides, polyesters, polyurethanes, and mixtures thereof. The second polycarbonate acid material Boxyl-functional is preferably crystalline. These second possible functional polycarboxylic acid materials can provide better flexibility, impact resistance and less yellowing in the polymerized ones, for example cured coatings, obtained from the thermosetting composition. These optional functional carboxylic acid materials also aid in the flow during curing, thereby providing smooth glossy polymers, for example bright coatings. The amount of second possible polycarboxylic-functional acid material present in the composition of the present invention will depend on whether it is crystalline or amorphous. If it is crystalline, the second polycarboxylic functional acid material may optionally be present in the composition in an amount of 1 to 25 weight percent, preferably 5 to 20 weight percent, based on the total weight of the the resin solids. If it is amorphous, the second polycarboxylic functional acid material may optionally be present in the composition in an amount of 1 to 40 weight percent, preferably 15 to 35 weight percent, based on the total weight of the composition. the resin solids. Among the aliphatic dicarboxylic acids which may possibly be present in the thermosetting composition These include, but are not limited to, dodecanedioic acid, azelaic acid, adipic acid, 1,6-hexanedioic acid, succinic acid, pimelic acid, sebacic acid, maleic acid, itaconic acid, aconitic acid, and mixtures thereof. Preferably, the aliphatic dicarboxylic acid contains from 6 to 12 carbon atoms and is a crystalline solid at room temperature. In one embodiment of the present invention, dodecanedioic acid is preferred. Other suitable second functional polycarboxylic acid materials useful in the present invention include those represented by the following general formula XV: XV or O In the general formula XV, R is the residue of a polyol, E is a divalent linking group of 1 to 10 carbon atoms and n is an integer from 2 to 10. Examples of polyols from which R can derive from the General formula XV include, but are not limited to, ethylene glycol, di (ethylene glycol), trimethylolyl, trimethylolpropane, pentaerythritol, ditrimethylolpropane, dipentaerythritol, and mixtures thereof. As divalent linking groups from which E can be selected it is possible to include, but are not limited to, methylene, ethylene, propylene, isopropylene, butylene, pentylene, hexylene, heptylene, octylene, nonylene, decylene, cyclohexylene, for example 1,2-cyclohexylene, substituted cyclohexylene, for example 4-methyl-1,2-cyclohexylene, phenylene, for example 1,2-phenylene, and substituted phenylene, for example 4-methyl-1,2-phenylene and 4-carboxylic acid-1,2-phenylene. The divalent linking group E is preferably aliphatic. The second polycarboxylic functional acid material re-presented by the general formula XV is typically prepared with a polyol and a dibasic acid or cyclic anhydride. For example, trimethylolpropane and hexahydro-4-methylphthalic anhydride react with each other in a molar ratio of 1: 3, respectively, to form a crosslinking agent carboxylic acid functional This second particular functional polycarboxylic acid material can be described with reference to the formula general XV as follows: R is the trimethylolpropane residue, E is the divalent linking group 4-methyl-1,2-cyclohexylene and n is 3. The second functional-polycarboxylic acid materials described herein in relation to the general formula XV they also intend to include any unreacted starting material and / or coproducts, for example oligomeric species, resulting from their preparation and counting. nests in them. Polymeric carboxylic acid functional polyanhydrides that can be used in the present invention include those having number average molecular weights in the range of 400 to 2,500 and, preferably, 600 to 1,200. The number average molecular weights greater than 2,500 are generally undesirable, due to the tendency to produce poor physical stability, for example sintering of individual particulates, of the thermosetting composition. Examples of suitable polymeric anhydrides include, but are not limited to, poly (adipic anhydride), poly (azelaic anhydride), poly (sebacic anhydride), poly (dodecanedioic anhydride) and mixed acid anhydrides. Polymeric polyanhydrides can be prepared by methods recognized in the art, for example as described in U.S. Patent No. 4,937,288, at column 5, lines 3 through 8, the disclosure of which is incorporated herein by reference. The carboxylic acid functional polyesters which can be used in the present invention include both crystalline and amorphous polyesters. The preferred crystalline carboxylic acid-functional polyesters generally have an equivalent carboxylic acid weight of 150 at 750 and a number average molecular weight of 300 to 1,500. Useful carboxylic functional acid polyesters include those prepared from the condensation of aliphatic diols and aliphatic and / or aromatic polycarboxylic acids, preferably dicarboxylic acids. The preparation of crystalline and amorphous carboxylic acid-functional polyesters is described in greater detail in U.S. Patent No. 4,937,288, in column 5, line 9, to column 6, line 12, the description of which is hereby incorporated by way of example. reference. The polycarboxylic acid-functional polyurethanes that can be used in the compositions of the present invention can serve to improve the external durability of the polymers obtained therefrom. Polycarboxylic acid-functional polyurethanes can be prepared by methods well recognized in the art, which typically include a two-step process. In the first step, a hydroxy-functional polyurethane is prepared from polyols and polyisocyanates. In the second step, the hydroxy-functional polyurethane reacts further with a diacid or, preferably, a cyclic anhydride to form the polycarboxylic acid-functional polycarboxylic acid. The polycarboxylic acid-functional polyurethanes useful in the present invention they are described in greater detail in U.S. Patent No. 4,937,288, in column 6, lines 13 to 39, the description of which is hereby incorporated by reference. The equivalent ratio of carboxylic acid equivalents in the functional polycarboxylic acid polymer (a) to the epoxy equivalents in the epoxy functional polymer (b) is typically from 0.5: 1 to 1.5: 1 and, preferably, from 0.8: 1 to 1.2: 1. While equivalent ratios that fall outside this range are within the scope of the pre-sat invention, they are generally less desirable due to deficiencies in appearance and performance in the cured films obtained with them. The aforementioned ranges of ratios are also intended to include the carboxylic acid equivalents associated with any functional polycarboxylic acid material that may possibly be present in the composition. The thermosetting composition of the present invention usually also includes one or more curing catalysts to catalyze the reaction between the carboxylic acid groups of the functional polycarboxylic acid polymer and the epoxy groups of the epoxy-funeion polymer. Examples of useful curing catalysts include tertiary amines, for example methyldicocoamine, and tin compounds, example, triphenyltin hydroxide. The curing catalyst is typically present in the thermosetting composition in an amount of less than 5 weight percent, for example from 0.25 weight percent to 2.0 weight percent, based on the total weight of resin solids of the composition. The thermosetting composition of the present invention may also include pigments and fillers. Examples of pigments include, but are not limited to, inorganic pigments, for example titanium dioxide and iron oxides.; organic pigments, for example phthalocyanines, anthraquinones, quinacridones and thioindigos, and carbon blacks. Examples of fillers include, but are not limited to, silica, for example precipitated silicas, clay and barium sulfate. When used in the composition of the present invention, the pigments and fillers are typically present in amounts of 0.1 percent to 70 percent, based on the total weight of the thermosetting composition. More often, the thermosetting composition of the present invention is used as a transparent composition substantially free of pigments and fillers. The thermosetting composition of the present invention it may optionally contain additives, such as waxes, for flow and wetting; agents for flow control, for example poly (2-ethylhexyl) acrylate; degassing additives, such as benzoin; Adjuvant resin to modify and optimize the coating properties; antioxidants, and absorbers of ultraviolet light (UV). Examples of useful UV light absorbers and antioxidants include those marketed by Ciba-Geigy under the trademarks IRGANOX and TINUVIN. These eventual additives, when used, are typically present in amounts of up to 20 weight percent, based on the total weight of the thermosetting composition. The thermosetting composition of the present invention is typically prepared by first dry-blending the carboxylic-functional acid polymer, the epoxy-functional polymer and additives, such as flow control agents, degassing agents and catalysts, in a mixer, for example a Henshel pallet mixer. The mixer is operated for a sufficient period of time to result in a dry and homogeneous mixture of the charged materials therein. The homogeneous dry mix is then melt blended in an extruder, for example a double helix co-rotating extruder, operated in a range of temperature from 80 ° C to 140 ° C, for example from 100 ° C to 125 ° C. Optionally, the thermosetting composition can be melt blended in two or more stages. For example, a first molten mixture is prepared in the absence of curing catalyst. A second molten mixture is prepared at a lower temperature from a dry mixture of the first molten mixture and the curing catalyst. When used as a powder coating composition, the melt-blended thermosetting composition is typically milled at an average particle size of, for example, 15 to 30 microns. According to the present invention, there is also provided a method of coating a substrate, consisting of: (a) applying to said substrate a thermosetting composition, (b) coalescing said thermosetting composition to form a substantially continuous film and (c) curing said composition thermosetting by application of heat, wherein said thermosetting composition consists of a solid particulate mixture that can be corkable as previously described herein. The thermosetting composition of the present invention can be applied to the substrate by any appropriate means that is known to those of ordinary skill in the art. in the art. In general, the thermosetting composition is in the form of dry powder and applied by spray application. Alternatively, the powder can be suspended in a liquid medium, such as water, and applied by spraying. When the language "solid particulate mixable additive" is used in the specification and claims, the thermosetting composition may be in the form of a dry powder or in the form of a suspension. When the substrate is electrically conductive, the thermosetting composition is typically applied electrostatically. The application by electrostatic spray involves, in general, the extraction of the thermosetting composition from a fluidized bed and its propulsion through a corona field. The particles of the thermosetting composition are charged as they pass through the corona field and are attracted and deposited on the electrically conductive substrate, which is grounded. As the charged particles begin to accumulate, the substrate is isolated, thus limiting further deposition of particles. This isolation phenomenon typically limits the growth of the film of the deposited composition to a maximum of 3 to 6 mils (75 to 150 microns). Alternatively, when the substrate is not electric- conductive mind, for example as in the case of many plastic substrates, the substrate is typically preheated before the application of the thermosetting composition. The preheated temperature of the substrate is equal to or higher than the melting point of the thermosetting composition, but lower than its curing temperature. With spray application on preheated substrates, film build-ups of the thermosettable composition can be achieved above 6 mil (150 microns), for example 10 to 20 mils (254 and 508 microns). Substrates which may be coated by the method of the present invention include, for example, ferrous substrates, aluminum substrates, plastic substrates, for example plastics based on sheet molding compounds, and wood. Upon application to the substrate, the thermosetting composition is then coalesced to form a substantially continuous film. The coalescence of the applied composition is generally achieved by the application of heat at a temperature equal to or higher than the melting point of the composition, but less than its curing temperature. In the case of preheated substrates, the application and coalescence steps can be carried out essentially in a single step.

The coalesced thermosetting composition is then cured by application of heat. As used herein and in the claims, "cured" means a three-dimensional crosslinking network formed by the formation of covalent bonds, for example, between the reactive functional groups of the coreactant and the epoxy groups of the polymer. The temperature at which the thermosetting composition of the present invention cures is variable and depends, in part, on the type and amount of the catalyst employed. 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 presented a coating composition composed of multiple components consisting of: (a) a base layer deposited from a pigmented film-forming composition and (b) a transparent outer layer applied on said base layer, where said transparent outer layer is deposited from a transparent film-forming thermosetting composition, consisting of a solid particulate mixable as described above. Reference is made to the composite coating composition multi-component taper described herein as a colored-plus-clear coating composition. The pigmented film-forming composition from which the base layer is deposited can be any of the compositions useful in coating applications, particularly in automotive applications, where colored-plus-clear coating compositions are widely used. The pigmented film-forming compositions conventionally contain a resinous binder and a pigment which acts as a dye. Particularly useful resinous binders are acrylic polymers, polyesters, including alkalis, and polyurethanes. The resinous binders for the pigmented film forming basecoating composition may be organic solvent-based materials, such as those described in US Pat. No. 4,220,679, see column 2, line 24, column 4, line 40. In addition, water-based coating compositions, such as those described in US Pat. 4,403,003, 4,147,679 and 5,071,904, as a binder in the pigmented film-forming composition. The pigment film forming base coat composition It is colored and may also contain metallic pigments. Examples of suitable pigments can be found in US Pat. 4,220,679, 4,403,003, 4,147,679 and 5,071,904. The components that may optionally be present in the pigmented film-forming basecoating composition are those which are well known in the art of surface coating formulation and include surfactants, flow control agents, thixotropic agents, fillers, anti-gas agents , organic cosolvents, catalysts and other common auxiliary compounds. Examples of these eventual materials and of the suitable amounts are described in U.S. Pat. aforementioned 4,220,679, 4,403,003, 4,147,769 and 5,071,904. The pigmented film-forming basecoating composition can be applied to the substrate by any of the conventional coating techniques, such as brush-painting, spraying, dipping or spillage, but is more often applied by spraying. The usual spray techniques and equipment can be used for air spraying, airless spraying and electrostatic spraying, using manual or automatic methods. The pigmented film forming composition is applied each in a sufficient amount to obtain a base layer with a film thickness typically of 0.1 to 5 mils (2.5 to 125 microns) and, preferably, 0.1 to 2 mils (2, 5 to 50 microns). After the deposition of the pigmented film-forming basecoating composition on the substrate and before the application of the transparent outer layer, the basecoat may be cured or alternatively dried. Upon drying the deposited base layer, the organic solvent and / or water is removed from the basecoat film by heating or air passing over its surface. Suitable drying conditions will depend on the particular basecoat composition used and the environmental humidity in the case of certain water-based compositions. In general, the drying of the deposited base layer is carried out over a period of 1 to 15 minutes and at a temperature of 21 ° C to 93 ° C. The transparent outer layer is applied to the base layer deposited by any of the methods by which it is known that the powder coatings are applied. Preferably, the transparent outer layer is applied by electrostatic spray application, as previously described herein. When the transparent outer layer is applied over a deposited base layer that has been dried, the two coatings can be co-cured to form the multi-component coating composition of the present invention. Both the base layer and the transparent layer are heated together to jointly cure the two layers. Typically, curing conditions of 130 ° C to 160 ° C are employed for a period of 20 to 30 minutes. The transparent outer layer typically has a thickness in the range of 0.5 to 6 mils (13 to 150 microns), for example 1 to 3 mils (25 to 75 microns). The present invention is described in more detail in the following examples, which are intended to be illustrative only, since numerous modifications and variations thereto will be obvious to those skilled in the art. Unless otherwise indicated, all parts and percentages are by weight. Examples of AC synthesis The AC synthesis examples describe the preparation of carboxylic acid functional and epoxide functional acrylic polymers used in the powder coating compositions of Examples 1 and 2. The carboxylic acid functional polymer of Example A is a polymer comparative prepared by non-living radical polymerization. The carboxylic acid functional and epoxide functional polymers of Examples B and C are representative of polymers useful in the compositions thermosetting coating compositions of the present invention. The physical properties of the polymers of Examples AC are summarized in Table 1. In the AC Synthesis Examples, the following abbreviations are used for the monomers: methyl methacrylate (MAM), n-butyl methacrylate (MAn-B) , tertiary butyl methacrylate (MAt-B), methacrylic acid (AMA), glycidyl methacrylate (MAG) and isobutyl methacrylate (MAi-B). Example A A comparative carboxylic-functional acid polymer was prepared by conventional radical polymerization, i.e., uncontrolled or non-living, from the ingredients listed in Table A.

Table A Ingredients Parts by weight Load 1 Toluene 350 Initiator (a) 40 Load 2 MAM 100 MAn-B 350 AMA 50 (a) Initiator 2, 2'-azobis (2-methylbutanonitrile), obtained co- commercially from E. I. du Pont de Nemours and Company. Charge 1 was heated to the reflux temperature (at about 115 ° C) at atmospheric pressure, under a blanket of nitrogen, in a 2 liter round bottom flask equipped with a stirrer. of rotary vanes, a reflux condenser, a thermometer and a heating jacket coupled together in a feedback loop through a temperature controller, a nitrogen inlet opening and two addition openings. After holding Charge 1 for 30 minutes at reflux, Charge 2 was added over a period of 1 hour. Upon completion of the addition of Charge 2, the contents of the flask were refluxed for an additional 3 hours. The contents of the flask were then distilled in vacuo. While still molten, the distilled contents of the flask were transferred to a suitable shallow open vessel and allowed to cool to room temperature and harden. The solidified resin was then broken into smaller pieces, which were transferred to a closed container suitable for storage. Example B A carboxylic-functional acid copolymer useful in the thermosetting compositions of the present invention was prepared invention by radical polymerization by atomic transfer from the ingredients listed in Table B.

Table B Ingredients Parts by weight Toluene 350 Copper (II) bromide (b) 2.0 Copper powder (c) 2,2 2,2 '- Bipyridyl 7,4 Diethyl-2-bromo-2-methylmalonate 50,6 MAM 100 MAn-B 350 MAt-B 83 (b) Copper (II) bromide was in the form of flakes and was obtained from Aldrich Chemical Company. (c) The copper powder had an average particle size of 25 microns and a density of 1 gram / cm 3 and was commercially obtained from OMG Americas. The ingredients were all added to a 2-liter, 4-neck flask equipped with a motor-driven stainless steel stirring paddle, a water-cooled condenser and a heating mantle and a thermometer connected through a feed-back control device. temperature. The contents of the flask were heated to 85 ° C and kept at that temperature for 4 hours. The contents of the flask were then cooled, filtered and the solvent was removed by means of vacuum distillation. 350 ml of dioxane and a 3-fold molar excess (relative to the moles of MAt-B) of HCl (1 Molar in water) were added to the distilled resin. The mixture of resin, dioxane, HCl and water was refluxed in a suitable round bottom flask for 4 hours. The contents of the flask were then cooled to room temperature and the pH neutralized by the addition of sodium carbonate. The neutralized contents of the flask were filtered and water and dioxane were removed by vacuum distillation in a suitable flask. While they were still molten, the distilled contents of the flask were transferred to a suitable shallow open container and allowed to cool to room temperature and harden. The solidified resin was then broken into smaller pieces, which were then transferred to a closed container suitable for storage. Example C An epoxy-functional tetrablock copolymer useful in the thermosetting compositions of the present invention was prepared by radical polymerization by transfer atomic concentration from the ingredients listed in Table C. The epoxy-functional block copolymer of this example is summarized diagrammatically as follows: (MAG) - (MAi-B) - (MAG) - (MAn-B) Table C Ingredients Parts by weight Load 1 Toluene 500.7 Copper (II) bromide (b) 10.9 Copper powder (c) 15.25 2.2 '-Bipyridyl 26.24 p-Toluenesulfonyl chloride 288.8 MAG 511.2 Load 2 Toluene 245.7 MAi-B 682.6 Load 3 Toluene 329.1 MAG 511.2 Load 4 Toluene 245.7 MAn-B 511.2 Charge 1 was heated to 85 ° C and maintained at that temperature for one hour in a 5 liter 4-neck flask equipped as described in Example B. the contents of the flask were maintained at 85 ° C, Charge 2 was added over a period of 15 minutes, followed by 2 hours at 85 ° C. Charge 3 was then added over a period of 15 minutes, followed by 2 hours at 85 ° C. Charge 4 was added over a period of 15 minutes at a temperature of the flask contents of 85 ° C, followed by 2 hours at 85 ° C. The contents of the flask were cooled, filtered and the solvent was removed by means of vacuum distillation. While still molten, the distilled resin was transferred to a suitable shallow open vessel and allowed to cool to room temperature and harden. The solidified resin was then broken into smaller pieces, which were transferred to a closed container suitable for storage.

- "- N.D. = Not determined 2N.A. = Not applicable. (D) The molecular weight data were obtained by means of gel permeation chromatography using polystyrene standards The abbreviations are summarized as follows: Molecular number average (Mn) and weight average molecular weight (Mp). (e) polydispersity index (IPD) = (Mp / Mn). (f) The values of the start, middle point and end point of the glass transition temperature (Tg) were determined by means of differential scanning calorimetry.

("DSC"). The polymer samples underwent a voltage release cycle, followed by heating at a rate of 10 ° C / minute. (g) Melt viscosities at 165 ° C to 180 ° C were determined using a Brookfield CAP 2000 High Temperature Viscometer. (h) The acid equivalent weight was determined by titration with potassium hydroxide and is shown in units of grams of polymer / acid equivalent. (i) The epoxy equivalent weight (grams of polymer / epoxy equivalent) was determined by titration using 0.1 Normal perchloric acid solution, (j) The percentage by weight of solids, based on the total weight, was determined from of samples of 0.2 grams at 110 ° C / 1 hour. Examples of powder coating compositions 1 and 2 Example 2 of powder coating is representative of a thermosetting coating composition according to the present invention, while Example 1 of powder coating is a thermosetting coating composition consisting of carboxylic-functional and epoxy-functional acid resins prepared by conventional methods of non-living radical polymerization. The powder coating compositions were prepared with the ingredients listed in Table 2.

Table 2 Powder coating compositions Ingredient Example 1 Example 2 Polymer of Example A 7 0 Acrylic resin epoxy 2.7 0 PD9060 (k) 0 7 Polymer of Example B 0 2.7 Polymer of Example C 0.3 0.3 Agent for control 0.1 0.1 flow (1) Benzoin (k) PD9060 resin is a solid epoxy-functional acrylic resin prepared by conventional polymerization of non-living radicals of acrylic monomers. It is marketed by An-derson Development Co. and was determined to have an epoxy equivalent weight of 375 grams of polymer / epoxy equivalent. (1) TROY 570 flow control agent, marketed by Troy Corporation. The ingredients listed in Table 2 were melt-mixed by hand using a spatula on a hot plate at a temperature of 175 ° C (347 ° F). The melt-mixed compositions were then coarsely sprayed by hand using a mortar and pestle with their hand. It was found that the thermosetting coarse particle coating compositions of Examples 1 and 2 had melt viscosities at 175 ° C (347 ° F) of 35 poise and 17 poise, respectively. The melt viscosities were determined using a temperature controlled cone and plate viscosity meter manufactured by Research Equipment (London) Ltd. The present invention has been described in relation to specific details of particular embodiments thereof. It is not intended to consider such details as limitations of the scope of the invention, except to the extent and extent to which they are included in the appended claims.

Claims

Claims 1. A thermosetting composition consisting of a solid particulate mixable drive of: (a) polycarboxylic acid functional polymer prepared by radical polymerization by atomic transfer initiated in the presence of a first initiator having at least one group transferable by radicals and wherein said acidic polymer polycarboxylic-functional contains at least one of the following polymer chain structures: - [(M1) t- (A) U] Vy - [(A) u- (M1) t] v- where M1 is a residue, which is free of carboxylic acid functionality, of at least one ethylenically unsaturated radical polymerizable monomer; A is a residue, having carboxylic acid functionality, of at least one ethylenically unsaturated radical polymerizable monomer; t and u represent average numbers of the residues that appear in a block of residues in each polymer chain structure, and t, u and v are each independently selected for each structure, such that said polycarboxylic-functional acid polymer has a number average molecular weight of at least 250; and (b) epoxy-functional polymer prepared by radical polymerization by atomic transfer initiated in the presence of a second initiator having at least one radical-transferable group and wherein said epoxy-functional polymer contains at least one of the following polymer chain structures : - [(M) p- (G) q] xy where M is a residue, which is free of oxirane functionality, of at least one ethylenically unsaturated radical polymerizable monomer; G is a residue, having oxirane functionality, of at least one monomer polymerizable by ethylenically unsaturated radicals; p and q represent average numbers of the residues that appear in a block of residues in each polymer chain structure, and p, q and x are each individually selected for each structure, such that said epoxy functional polymer has a number average molecular weight of minus 250.
2. The composition of claim 1, wherein said polycarboxylic acid functional polymer (a) and said epoxy functional polymer (b) are each independently selected from the group consisting of between the group consisting of linear polymers, branched polymers, hyperbranched polymers, star polymers, graft polymers and their mixtures. The composition of claim 1, wherein said polycarboxylic acid functional polymer (a) and said epoxy functional polymer (b) each independently have a number average molecular weight of 500 to 16,000 and a polydispersity index of less than 2. , 0. The composition of claim 1, wherein said first and second initiators are each independently selected from the group consisting of linear or branched aliphatic compounds, cycloaliphatic compounds, aromatic compounds, polycyclic aromatic compounds, heterocyclic compounds, sulfonyl compounds, sulfenyl compounds, esters of carboxylic acids, polymeric compounds and mixtures thereof, each with at least one halide transferable by radicals. The composition of claim 4, wherein said first and second primers are each independently selected from the group consisting of halomethane, methylene dichloride, haloform, carbon tetrahalide, 1-halo-2,3-epoxypropane, halide of methanesulfonyl, p-toluenesulfonyl halide, methanesulfenyl halide, p-halide toluensulfenyl, 1-phenylethyl halide, C-C6 alkyl ester of 2-halocarboxylic acid C? -C6, p-halomethylstyrene, mo-nohexakis (-halo-C6-alkyl) benzene, diethyl-2-malonate -halo-2-methyl, ethyl 2-bromoisobutyrate and their mixtures. The composition of claim 1, wherein said polycarboxylic acid functional polymer (a) has an equivalent carboxylic acid weight of 100 to 10,000 grams / equivalent and said epoxy functional polymer (b) has an epoxy equivalent weight of 100 to 10,000 grams / equivalent. 7. The composition of claim 1, wherein M1 and M each independently derive at least one of vinyl monomers, allylic monomers and olefins. The composition of claim 7, wherein M1 and M each independently derive from at least one of alkyl (meth) acrylates having from 1 to 20 carbon atoms in the alkyl group, vinyl aromatic monomers, vinyl halides , vinyl esters of carboxylic acids and olefins. The composition of claim 1, wherein A is derived from: alkyl (meth) acrylate, which, after polymerization, is hydrolyzed; or at least one hydroxy-functional ethylenically unsaturated monomer and radically polymerizable, which, after polymerization, post-reacts with a cyclic anhydride. The composition of claim 1, wherein G is derived from at least one of glycidyl (meth) acrylate, 3, 4-epoxycyclohexylmethyl (meth) acrylate, 2- (3,4-epoxycyclohexyl) ethyl (meth) acrylate and allyl glycyl ether. The composition of claim 1, wherein said functional polycarboxylic acid polymer (a) has at least one of the following polymer chain structures: f1 - [[(M1) t- (A) u] v- (M1) j-T1] 1 and ^ - [[(A? u-ÍM ^ -tAJk-T1]! where f1 is, or derives from, the residue of said first free initiator of said radical transferable group; T1 is, or is derived from, of said group transferable by radicals of said first initiator, v is independently from 1 to 100 for each structure, and t and u are each independently in the range of 0 to 100 for each v-segment and for each structure, the sum of t and u being at least 1 for each v-segment, and u being at least 1 for each one v-segment, j and k are each independently for each structure in the range of 0 to 100, 1 is independently for each structure at least 1, and said Polycarboxylic-functional acid polymer has a polydispersity index of less than 2.0; said epoxy-functional polymer (b) has at least one of the following polymer chain structures: f2 - [[(M) p- (G) q] x- (M) r-T2] z f "- [[(G) q- (M) p] x- (G) sT]] z where f2 is, or derives from, the residue of said second free initiator of said radical transferrable group; T2 is, or derived from said radical-transferable group of said second initiator, x is independently from 1 to 100 for each structure, and p and q are each independently within the range of 0 to 100 for each x-segment and for each structure, the sum of which is p and q at least 1 for each x-segment and q being at least 1 for at least one x-segment, - r and s are each independently for each structure in the range from 0 to 100, z is independently for each structure at least 1, and said epoxy functional polymer has a polydispersity index of less than 2.0 12. The composition of claim 11, wherein said polycarboxylic acid functional polymer (a) has an equivalent carboxylic acid weight of 100 to 10,000 grams / equivalent, said epoxy-functional polymer (b) has an epoxy equivalent weight of 100 to 10,000 grams / equivalent and said polycarboxylic-functional acid polymer and said poly Epoxy-functional groupers each independently have a polydispersity index of less than 1.8. The composition of claim 11, wherein t is independently selected for each structure in the range of 1 to 20; u is independently selected for each structure in the range of 1 to 20; p is independently selected for given structure in the range of 1 to 20, and q is independently selected for each structure in the range of 1 to 20. The composition of claim 11, wherein v is independently selected for each structure in the range from 1 to 50 and x is independently selected for each structure in the range of 1 to 50. 15. The composition of claim 11, wherein T1 and T2 are each independently halide. 16. The composition of claim 15, wherein T1 and T2 each independently derive a post-dehalogenation reaction. The composition of claim 16, wherein said posthalogenation reaction consists of independently contacting each of said polymer with polycarboxylic acid functional and said epoxy functional polymer with a polymerizable ethylenically unsaturated compound limited by radicals. The composition of claim 17, wherein said radically polymerizable ethylenically unsaturated compound is selected from the group consisting of 1,1-dimethylethylene, 1,1-diphenylethylene, isopropenyl acetate, alpha-methylstyrene, 1, 1 -dialcoxyolefin and its combinations. 19. The composition of claim 11, wherein f1 and f2 are the same or different. 20. The composition of claim 1, wherein the equivalent ratio of carboxylic acid equivalents in said polycarboxylic acid functional polymer (a) to epoxy equivalents in said epoxy functional polymer (b) is from 0.5: 1 to 1.5: 1. The composition of claim 1, wherein said polycarboxylic acid functional polymer (a) is present in said thermosetting composition in amounts of 5 to 95 percent by weight, based on the total weight of resin solids, and said The epoxy-functional polymer (b) is present in said thermosetting composition in an amount of 5 to 95 weight percent, based on the total weight of the ream solids. 22. The composition of claim 1, which alsoincludes a second functional polycarboxylic acid material selected from the group consisting of: C4 to C2o dicarboxylic acid acids, functional carboxylic acid materials represented by the following general formula: where R is the residue of a polyol, E is a divalent linking group having from 2 to 10 carbon atoms and n is an integer from 2 to 10, and mixtures thereof. The composition of claim 22, wherein said dicarboxylic acid is selected from the group consisting of dodecanedioic acid, azelaic acid, adipic acid, 1,6-hexanedioic acid, succinic acid, pimelic acid, sebacic acid, maleic acid, itaconic acid , aconitic acid and its mixtures; said polyol from which R is derived is selected from the group consisting of ethylene glycol, di (ethylene glycol), trimethylolethane, trimethylolpropane, pentaerythritol, ditrime-tylolpropane and dipentaerythritol; E is selected from the group consisting of 1,2-cyclohexylene and 4-methyl-1,2-cyclohexylene, and n is an integer from 2 to 6, being pre- said second polycarboxylic-functional acid material in said thermosetting composition in an amount of 1 percent to 25 percent by weight, based on the total weight of resin solids. 24. A method of coating a substrate, comprising: (a) applying a thermosetting composition to said substrate, (b) coalescing said thermosetting composition to form a substantially continuous film, and (c) curing said thermosetting composition by application of heat. , wherein said thermosetting composition consists of a solid particulate mixture coactable of: (i) a functional polycarboxylic acid polymer prepared by radical polymerization by atomic transfer initiated in the presence of a first initiator having at least one radical transferrable group and wherein said polymer functional polycarboxylic acid contains at least one of the following polymer chain structures: - [(M ^ -IAJuJ - where M1 is a residue, which is free of acid functionality carboxylic acid of at least one ethylenically unsaturated radical polymerizable monomer; A is a residue, having carboxylic acid functionality, of at least one ethylenically unsaturated radical polymerizable monomer; tyu represent average numbers of the residues that appear in a block of residues in each polymer chain structure, and t, u and v are each independently selected for each structure, such that said functional polycarboxylic acid polymer has a number average molecular weight of at least 250; and (ii) epoxy-functional polymer prepared by radical polymerization by atomic transfer initiated in the presence of a second initiator having at least one radical-transferable group and wherein said epoxy-functional polymer contains at least one of the following polymer chain structures : -_ (M) p- (G) q_x-y - [(G) q- (M) P] X- where M is a residue, which is free of oxirane functionality, of at least one ethylenically radical polymerizable monomer unsaturated; G is a residue, having oxirane functionality, of at least one polymerizable monomer per radical ethylenically unsaturated dicales; p and q represent average numbers of the residues that appear in a block of residues in each polymer chain structure, and p, q and x are each individually selected for each structure, such that said epoxy functional polymer has a number average molecular weight of minus 250. 25. The method of claim 24, wherein said polymer functional polycarboxylic acid (i) and said epoxy functional polymer (ii) are each independently selected from the group consisting of linear polymers, branched polymers, polymers hyperbranched, star polymers, graft polymers and their mixtures. 26. The method of claim 24, wherein said polymer functional polycarboxylic acid (i) and said epoxy functional polymer (ii) each independently have a number average molecular weight of 500 to 16,000 and a polydispersity index of less than 2., 0. The method of claim 24, wherein said first and second primers are each independently selected from the group consisting of linear or branched aliphatic compounds, cycloaliphatic compounds, aromatic compounds, polycyclic aromatic compounds, heterocyclic compounds, sulfonyl compounds, compounds sui- phenyl, esters of carboxylic acids, polymeric compounds and their mixtures, each of them with at least one halide transferable by radicals. The method of claim 27, wherein said first and second initiators are each independently selected from the group consisting of halomethane, methylene dihaluoro, haloform, carbon tetrahalide, 1-halo-2,3-epoxypropane , methanesulfonyl halide, p-toluenesulfonyl halide, methanesulfenyl halide, p-toluenesulfenyl halide, 1-phenylethyl halide, Ci-Cs alkyl ester of 2-halocarboxylic acid C _.- C6, p-halomethylstyrene, mo-nohexakis (-haloalkyl-C -C6) benzene, diethyl-2-halo-2-methyl malonate, ethyl 2-bromoisobutyrate and their mixtures. 29. The method of claim 24, wherein said polycarboxylic acid functional polymer (i) has an equivalent carboxylic acid weight of 100 to 10,000 grams / equivalent and said epoxy functional polymer (ii) has an epoxy equivalent weight of 100 to 10,000 grams / equivalent. 30. The method of claim 24, wherein M1 and M each independently independently of at least one of vinyl monomers, allylic monomers and olefins. The method of claim 30, wherein M1 and M each independently derive at least one of (meth) alkyl acrylates having 1 to 20 carbon atoms in the alkyl group, vinyl aromatic monomers, vinyl halides, vinyl esters of carboxylic acids and olefins. 32. The method of claim 24, wherein A is derived from: alkyl (meth) acrylate, which, after polymerization, is hydrolyzed; or at least one hydroxy functional ethylenically unsaturated monomer and radically polymerizable, which, after polymerization, post-reacts with a cyclic anhydride. The method of claim 24, wherein G is derived from at least one of glycidyl (meth) acrylate, 3,4-epoxycyclohexylmethyl (meth) acrylate, 2- (3,4-epoxycyclohexyl) ethyl (meth) acrylate. and allyl glycidyl ether. 34. The method of claim 24, wherein said polymer functional polycarboxylic acid (i) has at least one of the following polymer chain structures: f1 - [[(M1) t- (A) v- (M1) j- T1] 1 and where f1 is, or derives from, the residue of said first free initiator of said radical-transferable group; T1 is, or is derived from, said group transferable by radicals of said first initiator; v is independently from 1 to 100 for each structure; t and u are each independently in the range of 0 to 100 for each v-segment and for each structure, the sum of t and u being at least 1 for each v-segment, and u being at least 1 for each a v-segment; j and k are each independently for each structure in the range of 0 to 100; 1 is independently for each structure at least 1, and said polycarboxylic-functional acid polymer has a polydispersity index of less than 2.0; and said epoxy-functional polymer (ii) has at least one of the following polymer chain structures: f2 - [[(M) p- (G) q] x- (M) r-T2] z f - [[(G) q- (M) p] x- (G) s-T2] z where f2 is, or derives from, the residue of said second free initiator of said radical-transferable group; T2 is, or is derived from, said group transferable by radicals of said second initiator; x is independently from 1 to 100 for each structure; p and q are each independently within the range of 0 to 100 for each x-segment and for each structure, the sum of p and q being at least 1 for each x-segment and q being at least 1 for at least one x-segment , - rys are each independently for each structure in the range from 0 to 100; z is independently for each structure at least 1, and said epoxy-functional polymer has a polydispersity index of less than 2.0. 35. The method of claim 34, wherein said polymer-functional polycarboxylic acid (i) has an equivalent carboxylic acid weight of 100 to 10,000 grams / equivalent, said epoxy-functional polymer (ii) having an epoxy equivalent weight of 100 to 10,000 grams / equivalent and said polycarboxylic-functional acid polymer and said epoxy-functional polymer each independently have a polydispersity index of less than 1.8. 36. The method of claim 34, wherein t is independently selected for each structure in the range of 1 to 20; u is independently selected for each structure in the range of 1 to 20; p is independently selected for given structure in the range of 1 to 20, and q is independently selected for each structure in the range of 1 to 20. 37. The method of claim 34, wherein v is inde- pendently selected for each structure in the range of 1 to 50 and x is independently selected for each structure in the range of 1 to 50. 38. The method of claim 34, wherein T1 and T2 are each independently halide. 39. The method of claim 38, wherein T1 and T2 each independently derive a post-dehalogenation reaction. 40. The method of claim 39, wherein said posthalogenation reaction consists of independently contacting each of said polymer with polycarboxylic functional acid and said epoxy functional polymer with a radically polymerizable ethylenically unsaturated compound limited. 41. The method of claim 40, wherein said radically polymerizable ethylenically unsaturated compound is selected from the group consisting of 1,1-dimethylethylene, 1,1-diphenylethylene, isopropenyl acetate, alpha-methylstyrene, 1,1-dialkoxyolefin and its combinations. 42. The method of claim 34, wherein f1 and f2 are the same or different. 43. The method of claim 24, wherein the equivalent ratio of carboxylic acid equivalents in said polycarboxylic acid functional polymer (i) to epoxy equivalents in said epoxy functional polymer (ii) is 0.5: 1 to 1,5: 1. 44. The method of claim 24, wherein said poly- mere polycarboxylic-functional acid (i) is present in said thermosettable composition in amounts of 5 to 95 weight percent, based on the total weight of resin solids, and said epoxy functional polymer (ii) is present in said thermosetting composition in an amount of 5 to 95 weight percent, based on the total weight of resin solids. 45. The composition of claim 24, further comprising a second functional polycarboxylic acid material selected from the group consisting of: acid C to C2 dicarboxylic acids or functional carboxylic acid materials represented by the following general formula: where R is the residue of a polyol, E is a divalent linking group having from 2 to 10 carbon atoms and n is an integer from 2 to 10, and mixtures thereof. 46. The method of claim 45, wherein said dicarboxylic acid is selected from the group consisting of dodecanedioic acid, azelaic acid, adipic acid, acid 1,6-hexanedioic acid, succinic acid, pimelic acid, sebacic acid, maleic acid, itaconic acid, aconitic acid and mixtures thereof; said polyol from which R is derived is selected from the group consisting of ethylene glycol, di (ethylene glycol), tri-methylolethane, trimethylolpropane, pentaerythritol, ditrimethyolpropane and dipentaerythritol; E is selected from the group consisting of 1,2-cyclohexylene and 4-methyl-1,2-cyclohexylene, and n is an integer from 2 to 6, said second functional-polycarboxylic acid material being present in said thermosetting composition in an amount from 1 percent to 25 percent by weight, based on the total weight of resin solids. 47. A substrate coated by the method of claim 24. 48. A coating composition composed of multiple components consisting of: (a) a base layer deposited on a pigmented film-forming composition and (b) a transparent outer layer applied on said base layer, wherein said transparent outer layer is deposited from a transparent film-forming thermosetting composition consisting of a solid particulate mix that can be co-activated with: (i) polycarboxylic-functional acid polymer, prepared by radical polymerization by atomic transfer initiated in the presence of a first initiator having at least one radical-transferable group and wherein said polycarboxylic-functional acid polymer contains at least one of the following structures of polymer chain: [(M1) t- (A) U] V- - [(A) u- (M1) t] v- where M1 is a residue, which is free of carboxylic acid functionality, of at least one ethylenically unsaturated radical polymerizable monomer; A is a residue, having carboxylic acid functionality, of at least one ethylenically unsaturated radical polymerizable monomer; tyu represent average numbers of the residues that appear in a block of residues in each polymer chain structure, and t, u and v are each independently selected for each structure, such that said functional polycarboxylic acid polymer has a number average molecular weight of at least 250; and (ii) epoxy-functional polymer prepared by radical polymerization by atomic transfer initiated in the presence of a second initiator having at least one group transferable by radicals and wherein said epoxy-functional polymer contains at least one of the following polymer chain structures: - [(G) q- (M) p] x- where M is a residue, which is free of oxirane functionality, of at least one ethylenically unsaturated radical polymerizable monomer; G is a residue, having oxirane functionality, of at least one ethylenically unsaturated radical polymerizable monomer; p and q represent average numbers of the residues that appear in a block of residues in each polymer chain structure, and p, q and x are each individually selected for each structure, such that said epoxy functional polymer has a number average molecular weight of minus 250. 49. The multi-component composite coating composition of claim 48, wherein said functional polycarboxylic acid polymer (i) and said epoxy functional polymer (ii) are each independently selected from the group consisting of linear polymers, branched polymers, hyperbranched polymers, star polymers, graft polymers and mixtures thereof. 50. The multi-component composite coating composition of claim 48, wherein said functional polycarboxylic acid polymer (i) and said epoxy functional polymer (ii) each independently have a number average molecular weight of 500 to 16,000 and a polydispersity index less than 2.0. 51. The multi-component composite coating composition of claim 48, wherein said first and second initiators are each independently selected from the group consisting of linear or branched aliphatic compounds, cycloaliphatic compounds, aromatic compounds, polycyclic aromatic compounds, heterocyclics, sulfonyl compounds, sulfenyl compounds, esters of carboxylic acids, polymeric compounds and their mixtures, each of them with at least one halide transferable by radicals. 52. The multi-component composite coating composition of claim 51, wherein said first and second initiators are each independently selected from the group consisting of halomethane, methylene dihalide, haloform, carbon tetrahalide, l-halo-2. , 3-epoxypropane, methanesulfonyl halide, p-toluenesulfonyl halide, methanesulfenyl halide, p-halide toluensulfenyl, 1-phenylethyl halide, Ci-C6 alkyl ester of 2-halocarboxylic acid C? -C3, p-halomethylstyrene, mo-nohexakis (-haloalkyl-C? -C6) benzene, diethyl-2-halo 2-methyl, ethyl 2-bromoisobutyrate and their mixtures. 53. The multi-component composite coating composition of claim 48, wherein said functional polycarboxylic acid polymer (i) has an equivalent carboxylic acid weight of 100 to 10,000 grams / equivalent and said epoxy-functional polymer (ii) has an Epoxy equivalent weight of 100 to 10,000 grams / equivalent. 54. The multi-component composite coating composition of claim 48, wherein M1 and M each independently derive from at least one of vinyl monomers, allylic monomers and olefins. 55. The multi-component composite coating composition of claim 54, wherein M1 and M each independently derive from at least one of alkyl (meth) acrylates having 1 to 20 carbon atoms in the alkyl group, aromatic monomers of vinyl, vinyl halides, vinyl esters of carboxylic acids and olefins, 56. The multi-component composite coating composition of claim 48, wherein A is derived from: (meth) alkyl acrylate, which, after polymerization, is hydrolyzed; or at least one hydroxy-functional, ethylenically unsaturated and radically polymerizable monomer which, after polymerization, post-reacts with a cyclic anhydride. 57. The multi-component composite coating composition of claim 48, wherein G is derived from at least one of glycidyl (meth) acrylate, 3-epoxycyclohexylmethyl (meth) acrylate, 2- (3,4-epoxycyclohexyl) ethyl (meth) acrylate and allyl glycidyl ether. 58. The multi-component composite coating composition of claim 48, wherein said functional polycarboxylic acid polymer (i) has at least one of the following polymer chain structures: ^ - [[(M ^ t-fAj-tM ^ j-T1]! and 1- [[ { A) -. { ML) t] v-. { A) k-T1] 1 where f1 is, or derives from, the residue of said first free initiator of said radical transferable group; T1 is, or is derived from, said group transferable by radicals of said first initiator; v is independently from 1 to 100 for each structure; t and u are each independently in the range of 0 to 100 for each v-segment and for each structure, the sum of t and u being at least 1 for each v-segment, and u being at least 1 for each a v-segment; j and k are each independently for each structure in the range of 0 to 100; 1 is independently for each structure at least 1, and said polycarboxylic-functional acid polymer has a polydispersity index of less than 2.0; and said epoxy functional polymer (ii) has at least one of the following polymer chain structures: f2 - [[(M) p- (G) q] x- (M) r-T2] z and f2 - [[( G) q- (M) p] x- (G) s-T2] z where f2 is, or derives from, the residue of said second free initiator from said radical transferable group; T2 is, or is derived from, said group transferable by radicals of said second initiator; x is independently from 1 to 100 for each structure; p and q are each independently within the range of 0 to 100 for each x-segment and for each structure, the sum of p and q being at least 1 for each x-segment and q being at least 1 for at least one x-segment; r and s are each independently for each structure in the range of 0 to 100, - z is independently for each structure at least 1, and said epoxy-functional polymer has a polydispersity index of less than 2.0. 59. The multi-component composite coating composition of claim 58, wherein said functional polycarboxylic acid polymer (i) has an equivalent carboxylic acid weight of 100 to 10,000 grams-mole / equivalent, said epoxy-functional polymer (ii) has an Epoxy equivalent weight of 100 to 10,000 grams / equivalent and said polycarboxylic-functional acid polymer and said epoxy-functional polymer each independently have a polydispersity index of less than 1.8. 60. The multi-component composite coating composition of claim 58, wherein t is independently selected for each structure in the range of 1 to 20; u is independently selected for each structure in the range of 1 to 20; p is independently selected for given structure in the range of 1 to 20, and q is independently selected for each structure in the range of 1 to 20. 61. The multi-component composite coating composition of claim 58, wherein v is independently selected for each structure in the range of 1 to 50 and x is independently selected for each structure in the range of 1 to 50. 62. The coating composition composed of multiple component feet of claim 58, wherein T1 and T2 are each independently halide. 63. The multi-component composite coating composition of claim 62, wherein T1 and T2 each independently derive a post-dehalogenation reaction. 64. The multi-component composite coating composition of claim 63, wherein said post-dehalogenation reaction consists of independently contacting each of said polymer functional polycarboxylic acid and said epoxy functional polymer with an ethylenically bound compound. unsaturated radical polymerizable. 65. The multi-component component coating composition of claim 64, wherein said ethylenically unsaturated radical polymerizable compound is selected from the group consisting of 1,1-dimethylethylene, 1,1-diphenylethylene, isopropenyl acetate, alpha -methylstyrene, 1, 1-dialkoxyolefin and combinations thereof. 66 The multi-component composite coating composition of claim 58, wherein f1 and f2 are the same or different. 67. The composite coating composition of multiple component feet of claim 48, wherein the equivalent ratio of carboxylic acid equivalents in said polycarboxylic acid functional polymer (i) to epoxy equivalents in said epoxy functional polymer (ii) is from 0.5: 1 to 1.5: 1. 68. The multi-component composite coating composition of claim 48, wherein said functional polycarboxylic acid polymer (i) is present in said thermosetting composition in amounts of 5 to 95 weight percent, based on the total weight of resin solids, and said epoxy functional polymer (ii) is present in said thermosetting composition in an amount of 5 to 95 weight percent, based on the total weight of resin solids. 69. The multi-component composite coating composition of claim 48, further comprising a second functional polycarboxylic acid material selected from the group consisting of: acid C to C20 dicarboxylic acids, functional carboxylic acid materials represented by the following General Formula: where R is the residue of a polyol, E is a divalent linking group having from 2 to 10 carbon atoms and n is an integer from 2 to 10, and mixtures thereof. 70. The multi-component composite coating composition of claim 69, wherein said dicarboxylic acid is selected from the group consisting of dodecanedioic acid, azelaic acid, adipic acid, 1,6-hexanedioic acid, succinic acid, pimelic acid, -bacic, maleic acid, itaconic acid, aconitic acid and their mixtures; said polyol from which R is derived is selected from the group consisting of ethylene glycol, di (ethylene glycol), tri-methylolethane, trimethylolpropane, pentaerythritol, ditrimethyolpropane and dipentaerythritol; E is selected from the group consisting of 1,2-cyclohexylene and -methyl-1,2-cyclohexylene, and n is an integer from 2 to 6, said second functional-polycarboxylic acid material being present in said thermosetting composition in an amount of 1 percent to 25 percent by weight, based on total weight of resin solids. 71. A substrate having said multi-component coating composition of claim 48 deposited thereon. 72. A substrate having said multi-component coating composition of claim 58 deposited thereon.