MXPA98003550A

MXPA98003550A - Composition for stabilized polyester molding ultraviol light

Info

Publication number: MXPA98003550A
Application number: MXPA/A/1998/003550A
Authority: MX
Inventors: M Mulholland Bruce
Original assignee: Hoechst Celanese Corporation
Filing date: 1998-04-30
Publication date: 1999-12-10

Abstract

A thermoplastic polyester molding composition stabilized against UV characterized in that it contains a polyester and a stabilization system against UV light as an effective amount of a hindered amine, a benzotriazole or benzophenone compound, and an antioxidant to achieve acceptable results of UV exposure When the composition is exposed to a Xenon arc meteorological meter operated in accordance with SAE J1885, the composition and the molded parts thereof show improved color difference, as calculated in CIELab units with "D-65" illumination in accordance with ASTM D-2244, less than about 2.20 when exposed to an irradiation of 601.6 kJ / cmý, and improved characteristics of surface gloss retention after exposure.

Description

COMPOSITION FOR POLYESTER MOLDING STABILIZED AGAINST ULTRAVIOLET LIGHT FIELD OF THE INVENTION The present invention relates to compositions for molding thermoplastic polyester stabilized against ultraviolet (UV) light suitable for the preparation of shaped articles. The polyester resins are combined with a UV stabilization system containing a light stabilizer made from hindered amine and an ultraviolet light absorber for preparing the molding composition. Molded articles prepared from the composition show increased stability against color degradation and loss of gloss caused by exposure to continuous UV light.

BACKGROUND OF THE INVENTION In the automotive industry they have been painting molded parts from a number of different polymer systems including polyester resins for several years. Historically, all these polymers have not possessed sufficient stability to ultraviolet light to allow the elimination of the painting process. The applied layer of optional UV coating and paint protected the polymer against UV degradation resulting in objectionable color and surface gloss degradation. The industry has been interested in eliminating the paint process to reduce costs as well as reduce air emissions due to the use of paints and solvents. It is known that polyester resins, for example, copolyester elastomers, polyalkylene terephthalates, etc., which degrade when exposed to UV light for prolonged periods. This degradation typically manifests as a distinct and objectionable color change of the desired color of the molded articles. Specifically, when exposed to UV light and other environmental factors found within a car, the color of the polyester resins is generally degraded from the initial color to one that is distinctly discolored yellow to yellow-brown. This UV-induced decolorization has required that parts in the automotive industry continue to be painted in an attempt to avoid color degradation and loss of gloss or to select alternative polymer systems that possess desired performance characteristics critical to UV exposure applications. There is a desire for a stabilization system against UV light that when combined with polyester resins eliminate the need to apply surface paints and additives to molded parts for the prevention of color degradation and loss of gloss. Said stabilization system should require that small amounts thereof be combined with the polyesters so as not to adversely affect the physical properties or molding characteristics of the composition.

BRIEF DESCRIPTION OF THE INVENTION The present invention is directed to an ultraviolet light stabilized molding composition comprising a thermoplastic polyester resin and a UV stabilization system which, in combination with the polyester resin in an effective amount, is sufficient to achieve a color difference, as calculated in units of CIELab under illuminator "D-65" according to the ASTM D-2244 standard of less than about 2.25 when exposed to a irradiation of 601.6 kJ / m2 in a weather meter Xenon arc operated in accordance with SAE J1885 and shows a retention of surface loss after irradiation of at least about 7.5%, wherein said stabilization system includes: (i) an ultraviolet light absorber; (ii) a light stabilizer made from hindered amine; and (iii) an antioxidant. The composition is suitable for the preparation of molded articles for the automotive industry such as interior parts of automobiles, for example, dashboard controls, mounted dashboard and side impact airbag covers, etc., which can withstand the change of color, loss of brightness and surface deterioration when exposed to extreme UV lighting conditions for extended periods.

DETAILED DESCRIPTION OF THE INVENTION According to the present invention, a composition for thermoplastic polyester molding is described, characterized in that it contains a polyester resin and a stabilization system against UV light suitable for the preparation of molded articles resistant to degradation and color change when expose to UV light for extended periods. The polyester resin can be characterized as containing polyalkylene terephthalates, copolyester elastomers and optionally polycarbonates or mixtures thereof. The stabilization system against UV light that is added to the polyester resin can be characterized as containing a light stabilizer made of hindered amine and a stabilizer against UV light. In addition to the stabilization system, the composition may also contain an antioxidant and other additive components known in the art.

ELASTOMEROS DE COPOLIESTER A preferred class of thermoplastic polyesters suitable for use in the present invention are copolyester elastomers, for example, copolyether esters. Copolyester elastomers are characterized by a multiplicity of recurrent intralineal long chain and short chain ester units connected head to tail through ester linkages. The link chain ester units are represented by at least one of the following structures: O O O II H II ll,? o o o o WW) while the units of this short chain are represented at least by one of the following structures: O or II II II II 0CfeO-C?, C- jy -OQO - CI? aC- fß > w wherein (i) G is a divalent radical after the removal of terminal hydroxyl groups of a long chain polymer glycol, having a molecular weight of about 600 and a melting point below about 55 ° C; (ii) Ri and R2 are different divalent radicals remaining after the removal of carboxyl groups of different dicarboxylic acids each having a molecular weight of less than about 300; and (iii) Di and D2 are different divalent radicals remaining after the removal of hydroxyl groups from different low molecular weight diols, which have molecular weights less than about 250. The "short chain ester units" in the copolymer -esters provide approximately 25 to 95% of the copolyether ester, and approximately 50 to 100% by weight of the short chain ester units in the copolyether ester can be identical. The term "long chain ester units" as applied to units in a polymer chain refers to the reaction product of a long chain glycol with a dicarboxylic acid. Said "long chain ester units" which are repeating units in the copolyester elastomer correspond to formula I (a) or I (b) above. The long chain glycols are polymeric glycols having terminal (or near terminal) hydroxyl groups and a molecular weight of from about 600 to about 6000. The long chain glycols used to prepare the copolyesters of the invention are generally polyalkylene oxide glycols or esters of polyalkylene oxide dicarboxylic acids. The chemical structure of the long chain polymer part of the long chain glycol is not critical and any substituent groups which do not interfere with the polymerization of the compound with glycol (s) or dicarboxylic acid (s) can be present to form the polyesters of the invention »In this way, the chain can be a single acrylic, alicyclic or aromatic divalent hydrocarbon group, a polyalkylene oxide group, a polyester group, a combination thereof or the like that meets the other requirements that Here they are exposed. Any of these may contain substituents that do not substantially interfere with the polymerization to form the copolyester. The term "short chain ester units" as applied to units in a polyester chain refers to low molecular weight compounds or polymer chain units having molecular weights less than about 550. They are made by the reaction of a low molecular weight diol, for example, below 250, with a dicarboxylic acid to form a repeating unit corresponding to formula I (c), (d), (e) or (f) above. The term "dicarboxylic acid" as used herein includes the condensation polymerization equivalents of dicarboxylic acids, ie, their esters or ester-forming derivatives such as acid chlorides and anhydrides, or derivatives thereof, which behave substantially the same than dicarboxylic acids in polymerization reactions with a glycol. Suitable copolyesters in the composition of this invention can be prepared by polymerizing with each other a) one or more dicarboxylic acids or their equivalents (and esters and ester-forming derivatives such as anhydrous acid chlorides, etc.).; b) one or more linear long chain glycols; and c) one or more low molecular weight diols. The polymerization reaction can be carried out by conventional methods, for example, in bulk or in a solvent medium which dissolves one or more of the monomers. The "dicarboxylic acid monomers" useful herein have a molecular weight less than about 300, for example aromatic, aliphatic or cycloaliphatic. The dicarboxylic acids may contain any substituent groups or combinations thereof which do not interfere with the polymerization reaction. Representative dicarboxylic acids include terephthalic and isophthalic acids, dibenzoic acid, dicarboxylic compounds substituted with benzene cores such as bis (p-carboxyphenyl) methane, p-oxy- (p-carboxyphenyl) -benzoic acid, 2,7-naphidendicarboxylic acid , fenantralene dicarboxylic acid, antilelecarboxylic acid, 4,4'-sulfonyldibenzoic acid, etc., and Ci-Cι alkyl or other ring substitution derivatives such as halogen, alkoxy or aryl derivatives. Hydroxy acids such as p (β-hydroxyethoxy) benzoic acid may also be used provided that an aromatic dicarboxylic acid is also present. The "aromatic dicarboxylic acids" are dicarboxylic acids in which a carboxyl group is attached to a carbon atom and an isolated or fused benzene ring such as those mentioned above. "Aliphatic dicarboxylic acids" are acids in which each carboxyl group is attached to a fully saturated carbon atom or to a carbon atom that is part of an olefinic double bond. If the carbon atom is in a ring, then the acid is cycloaliphatic; if it is not, the acid is aliphatic. Representative aliphatic and cycloaliphatic acids are zebactic acid, 1,3- or 1,4-cyclohexanedicarboxylic acid, adipic acid, glutaric acid, succinic acid, carbonic acid, oxalic acid, itaconic acid, azelaic acid, diethylmalonic acid, fumaric acid, citraconic acid, allyl aliphatic acid, 4-cyclohexen-l, 2-dicarboxylic acid, pimelic acid, suberic acid, 2,5-diethyladipic acid, 2-ethylsuberic acid, 2,2,3,3-tetramethyl-succinic acid, cyclopentanedicarboxylic acid, decahydro-1,5- (or 2, -) naphthyl acid, the different isomers should be considered as different compounds forming different short chain ester units with the same diol in the copolyesters. In general, the short chain ester units of Formula II should contribute an amount of from about 25 to about 95% by weight of the copolyester, from about 50 to about 100% of the total short chain ester units. being identical, that is, the reaction product of a single low molecular weight dicarboxylic acid with a single low molecular weight diol. The short chain ester units will normally be distributed statistically throughout the polyester base structure. The copolyester elastomer can be prepared by means of a conventional ester exchange reaction. A preferred process involves heating the terephthalic acid dimethyl ester or a mixture of terephthalic and isophthalic acids with a long chain glycol and a molar excess of at least one butanediol and butenediol in the presence of a catalyst at a temperature of about 50 °. at approximately 260 ° C followed by the removal of the methanol formed by the exchange by distillation. The heating is continued until the evolution of methanol is complete. Depending on the reaction temperature, the catalyst and the excess glycol, the polymerization can be completed within a few minutes to a few hours. This procedure results in the preparation of a low molecular weight prepolymer which can be carried to a high molecular weight copolyester by distillation of excess short chain diol in a conventional polycondensation reaction. Additional ester exchange occurs during distillation to increase molecular weight and to randomize the disposition of the copolyester units. Normally better results are obtained if this final distillation or polycondensation is carried out at a pressure of less than 1 mm and at a temperature of about 225 ° to 260 ° C for at least about 2 hours in the presence of antioxidants such as sym-di- beta-naphthyl-p-phenylenediamine yl, 3,5-trimethyl-2,4-tris (3,5-ditertiari-butyl-4-hydroxybenzyl) benzene. Most practical polymerization techniques are based on ester exchange to complete the polymerization reaction. In order to avoid the excessive reaction time at high temperatures with possible irreversible thermal degradation, it is advantageous to employ a catalyst for ester exchange reactions. Although a wide variety of catalysts can be used, organic titanates such as tetrabutyl titanate or tetraisobutyl titanate used alone or in combination with magnesium or calcium acetates are preferred. Complex titanates, such as derivatives of alkali metal or alkaline earth metal alkoxides and titanate esters are also very effective. Inorganic titanates, such as lanthanum titanate, mixtures of calcium acetate / antimony trioxide and lithium magnesium alkoxide are representative of the catalysts that can be used. The prepolymers can also be prepared by a number of alternative esterification or ester exchange methods. For example, the long chain glycol can be reacted with a high or low molecular weight short chain ester homopolymer or copolymer in the presence of a catalyst until randomization occurs. The short chain ester homopolymer or copolymer can be prepared by ester exchange from dimethyl esters and low molecular weight diols, as above, or from the free acids with the diolate acetates. Alternatively, the short chain ester copolymer can be prepared by direct esterification of suitable acids, anhydrides and acid chlorides, for example, with diols or by other processes such as reaction of the acids with cyclic ethers or carbonates. Obviously, the prepolymer can also be prepared by performing these procedures in the presence of the long chain glycol. Ester exchange polymerizations are usually performed in the molten bath without added solvents, however, inert solvents can be used to facilitate the removal of volatile components from the mass at low temperatures. This technique is especially valuable during the preparation of the prepolymer, for example, by direct esterification. However, certain low molecular weight diols such as butanediol in terphenyl, are conveniently removed during high polymerization by azeotropic distillation. Other polymerization techniques, for example, interfacial polymerization of bisphenol with bisacyl halides and linear diols blocked with bisacyl halide, may prove useful for the preparation of specific polymers. Both loading and continuous methods can be used for any copolyester polymer preparation step. The polycondensation of s can also be achieved in the solid phase by heating the finely divided solids in a vacuum or stream of inert gas to remove the high molecular weight diols released. This method has the advantage of reducing the degradation, since it must be used at temperatures below the softening point of the prepolymer. The main disadvantage is the long time required to react a given degree of polymerization.

Polyalkylene terephthalates Another class of polyesters which may be useful for forming the ultraviolet light stabilized thermoplastic molding composition of the invention are polyalkylene terephthalates, generally polyethylene terephthalate (PET), polypropylene terephthalate (PPT), polybutylene terephthalate (PBT) and terephthalate. of ethylene-l, 4-cyclohexylenedimethylene (PETG). Of these, polybutylene terephthalate (PBT) is especially preferred. Polybutylene terephthalate can be prepared in a conventional manner such as by transesterification and polycondensation of dimethyl terephthalate or terephthalic acid or its lower alcohol ester and 1,4-butanediol. The polybutylene terephthalate base polymer is not strictly limited to PBT homopolymer, but also includes copolymers comprising primarily polybutylene terephthalate units. The term "copolymer" as used herein refers to polymers obtained by the polycondensation of terephthalic acid or its lower alcohol ester as the major dibasic acid component with 1,4-butanediol as the major glycol component in the presence of 40% molar or less than one ester-forming monomer. The comonomer components useful herein include dibasic acid components such as isophthalic acid, orthophthalic acid as well as their lower alcohol esters; and glycolic components such as common alkylene glycols other than 1,4-butanediol, e.g., ethylene glycol, diethylene glycol, propylene glycol, trimethylene glycol, hexamethylene glycol, neopentyl glycol and cyclohexanedenetanol as well as aromatic diols, e.g., bisphenol A and adduct of ethylene oxide (2 mol) of bisphenol A. Hydroxy acids such as hydroxybenzoic acid and hydroxynaphthoic acid and their ester-forming derivatives can also be used as suitable comonomers. The intrinsic viscosity (VI) and melt index of the PBT are not critical and variations in the melt index of the PBT or the elastomer do not appear to affect the mechanical properties of the compositions of the invention; however, a typical VI will be within the approximate range of 0.7 to 2.0. Commonly, the PBT useful herein has a melt index of about 6 to about 90 by the method ASTM D-1238 at 250 ° C using a load of 2160 g and an intrinsic viscosity of about 0.6 and about 1.2 dl / g as measured in orthochlorophenol at 25 ° C.

Polycarbonates Optionally, a polycarbonate can be combined with the thermoplastic polyester resin of the invention. The polycarbonate can be added to the individual polymers or to a mixture thereof. The polycarbonate resin of the invention can be blended homogeneously with polyester and polyalkylene terephthalates. Polycarbonate can be prepared by reacting a dihydric phenol with a carbonate precursor, such as phosgene, or transesterification of a water phenol with a carbonate precursor, such as diphenyl carbonate, in a solvent, such as methylene chloride, in the presence of a known acid acceptor and a molecular weight modifier. Suitable examples of the dihydric phenol include bisphenols, among which 1,1-bis (4-hydroxyphenyl) -hexane, for example, bisphenol A, is particularly preferred. Bisphenol A can be partially or completely replaced by other dihydric phenols. Examples of dihydric phenols other than bisphenol A include compounds such as hydroquinone, 4,4-dihydroxydiphenyl, bis (4-hydroxyphenyl) alkane, bis (4-hydroxyphenyl) cycloalkane, bis (4-hydroxyphenyl) sulfide, bis ( 4-hydroxyphenyl), bis (4-hydroxyphenyl) sulfoxide and bis (4-hydroxyphenyl) ether; and halogenated biphenols, such as bis (3,5-dibromo-4-hydroxyphenyl) propane and bis (3,5-dichloro-4-hydroxyphenyl) propane.

The dihydric phenol can be a homopolymer of a dihydric phenol, or a copolymer of two or more thereof. further, the polycarbonate resin used in the invention can be a branched thermoplastic polycarbonate randomly prepared by reacting a polyfunctional aromatic compound with a dihydric phenol and / or a carbonate precursor. The polycarbonate suitable for use in the invention should show a VI (at 20 ° C in methyl chloride) of at least about 0.4 or more. Generally, the thermoplastic polyester resin of the invention may contain from 0 to about 30 p% polyalkylene terephthalate, from about 35 to about 70 p% polyester elastomer, from 0 to about 30 p% polycarbonate, about 10. at about 50 p% MBS, and about 0.2 to about 1.0 p% of an antioxidant, commonly, the polyester composition of the invention will contain from 0 to about 30 p% polyalkylene terephthalate, from about 55 to about 65 p % polyester elastomer, 0 to about 15 p% polycarbonate, about 15 to about 45 p% MBS, and about 0.2 to about 0.8 p% antioxidant; preferably, from 0 to about 10 p% polycarbonate, from about 20 to about 40 p% polyester elatomer, from 0 to about 10 p% polycarbonate, from about 20 to about 40 p% MBS, and about 0.6 p% of the antioxidant, based on the total weight of the composition.

Stabilizer system against ultraviolet light The ultraviolet light stabilization system of the invention will contain a light stabilizer made of hindered amine, an ultraviolet light absorber and an antioxidant. The components of the stabilizer system can be combined together or added to the polymer resins, or the components can be mixed directly into the polymer resins. The thermoplastic resins of the invention have ultraviolet light stability and resistance to significantly increased climatic conditions when combined with the ultraviolet light stabilizer system described herein. The ultraviolet light stabilizer system shall include an ultraviolet light absorber compatible with the composition that is sufficient to achieve acceptable ultraviolet exposure results when exposed to a Xenon arc meteorological meter operated in accordance with SAEJ1885. Generally, ultraviolet light absorbers are based on benzophenones of the formula: where R 'is hydrogen or an alkyl radical of 1 to 8 carbons. More particularly, the benzophenones are 2-hydroxybenzophenones such as 2,4-dihydroxybenzophenone; 2-hydroxy-4-methoxy benzophenone; 2-hydroxy-4-tert-butoxybenzophenone; 2-hydroxy-4-octoxy benzophenone; 2-hydroxy-4-dodecylcycloxybenzo-phenone; 2-hydroxy-4-steroxybenzophenone; 2-hydroxy-4-phenoxybenzophenone; 2-hydroxy-4- (β-hydroxyethoxy) benzophenone; 2-hydroxy-4- (2 '-hydroxy-3'-acryloxypropoxyl) benzophenone; 2,2'-dihydroxybenzophenone; 2,2'-dihydroxy-4-methoxybenzophenone; 2,2'-dihydroxy-4-butoxybenzophenone; 2,2'-dihydroxy-4-octoxyben-zofenone; 2,2'-dihydroxy-4-lauroxybenzophenone; 2, 2 ', 4, 4'-tetrahydroxybenzophenone; 2,2 ', 4' -trihydroxy-4-methoxybenzo-phenone; 2-hydroxy-4-methoxy-4'-chlorobenzophenone; 2,2'-dihydroxy-4-dimethyloxybenzophenone; 2-hydroxy-4-methoxy-2'-methyl-4 '-hydroxybenzophenone; 2-hydroxy-4-methoxy-4'-tert-butylbenzo-phenone; 2-hydroxy-4-methoxy-4'-methyl-benzophenone; 2-hydroxy-4,4'-dimethoxybenzophenone; 2-hydroxy-4,4 ', 2'-trimethoxybenzo-phenone; 2-hydroxy-4-N-octyloxybenzophenone, etc. Ultraviolet light absorbers are also based on benzothiazoles, and more particularly 2-hydroxybenzotrialkols such as 2- (2'-hydroxy-5'-methyl phenyl benzothiazole; 2- (2'-hydroxy-3'-5 '- di-tert-butyl-phenyl) enzo ri azole; 2- (2'-hydroxy-3'-5'-di-tert-butylphenyl) -5-chlorobenzo triazole; 2- (2'-hydroxy-3 ', '-diphenyl-) -5-benzo-triazole; 2- (2'-hydroxy-3'-te rebu'-1-5' -methyl phenyl) -5-robenzo-triazole; 2- (2'-hydroxy) 5'-tert-Butyl-5 '-methylphenyl) benzotria-zol; 2- (2'-hydroxy-3'-secbuti 1-5' -te reused 1-f-enyl) benzothiazole; 2- (2'-hydroxy-5) -terc-octylphenyl) benzothiazole; 2- (2H-benzothiazol-2-yl) -4,6-bis (l-methyl-1-phenylethyl) -phenol; 2- (3 ', 5'-bis (l-methyl-l-phenylethyl) 2'-hydroxyphenyl) benzotriazole, etc. Generally, the effective amount of ultraviolet light absorber in the molding composition includes about 0.5 to about 5 p%, based on the total weight of the composition.The commercially available benzot riazoles Useful in the invention include Cyasorb ™ UV 5411-2- (2-hydroxy-5-t-oxtylphenyl) -benzotriazole available from American Cyana Id Company, and Tinuvin ™ 234-2- (3 ', 5' -bis (1-methyl-1-phenylethyl) -2'-hydroxyphenyl) benzotriazole available from Ciba-Geigy Corporation. Commercially available benzophenones useful in the invention include Cyasorb ™ UV531-2-hydroxy-4-N-octoxybenzophenone from American Cyanamid Company. Light stabilizers made of hindered amine (HALS) useful in the ultraviolet light stabilizing system include 1,1 '- [1,2-ethanediyl] -bis [3,3,5,5-tetramethylpoperazione]; dimethylsuccinate polymer with 4-hydroxy-2,2,6,6-tetramethyl-1-pipedine ethanol; bis (1, 2,2,6,6-pentamethyl-4-piperidyl) -sebacate; bis [2,2,6,6-tet ramethyl-4-piperidinyl] decanedioate; bis (1, 2,2,6,6-pentamethyl-4-piperidinyl) -2-C (3,5-bis (1, 1 -dimethylethyl) -4-hydrophenyl] methyl] -2-butylpropanedioate; poly [(2, 2,6,6-tetramethyl-4-piperidinyl) iminomeleno (2,2,6,6-tetramethyl-4-piperidinyl) imino [6 (octylamino) -l, 3,5-triazine-4 , 2-diyl]]; 2,2,6,6-tetramethyl-4-piperidinyl benzoate; tetrakis (2,2,6,6-tetramethyl-4-piperidinyloxy) silane and the like. Preferred commercially available HALS for the invention include Tinuvin ™ 144-bis (1, 2,2,6,6-pentamethyl-4-piperidinyl- (3,5-di-tert-butyl-4-hydroxybenzyl) butylpropane dioate, Hostavin ™ N20 and Hostavin ™ N30 - commercially available oligomeric / polymeric hindered amine light stabilizers commercially available from Hoechst AG, Frankfurt am Main, Germany; Sanol ™ LS770-2,2,6,6-tetramethylpiperidine; Goodrite 3150- a stabilizer against the light of hindered amine of B.F.

Goodrich; and Adka Stab LA63- [1,2,2,6,6-pentamethyl-4-piperidyl / β, β, β ', β' -te ramethyl-3,9- (2,4,8,10-tetraoxaspiro ( 5.5) undecane) diyl] -l, 2,3,4-bu anotetraca rboxylate. Generally, an effective amount of HALS will be included within the ultraviolet light stabilizing system to provide surface degradation protection of the thermoplastic polyester resin as a result of exposure to ultraviolet light. An effective amount of HALS in the molding composition includes about 0.5 to about 5 p%, based on the total weight of the composition. Commonly, the relative ratio of approximately 1: 1 to approximately 1: 2 HALS: VAT, respectively, will be included in the stabilized system, and a preferred ratio of approximately 1: 1 HALS: UVA. The ultraviolet light stabilizing system of the present invention will also contain about 0.5 to about 1.5 p%, based on the total weight of the composition of an antioxidant. Commonly the antioxidants are methane tetrakis [methylene (3,5-di-t-butyl-4-hydroxyhydro-cinnamate)], commercially available as Irganox 1010 from Ciba Geigy Corporation, and [tetrakis (2,4-di-tert-butylphenyl) ) 4,4-biphenyldiphosphonyl] commercially available from Sandostab P-EPQ available from Sandoz. In addition, lubricants, fillers include minerals, eg, talcum, calcium carbonate, mica, etc., mold release agents, plasticizers, core forming agents, impact modifiers, pigments and dyes; continuous length of reinforcing fiber strands selected from the group consisting of glass, amorphous carbon, graphite carbon, aramides, stainless steel, alumina, titanium, magnesium, metal-coated carbons, rock wool and combinations thereof.

EXAMPLES The following examples are presented as specific illustrations of the claimed invention. However, it should be understood that the invention is not limited to the specific details indicated in the examples. The polyester resins are premixed in dry form with various additives and post-mixed before molding as shown in the following tables. The dry mixes are subsequently extruded and compressed into pellets by single screw or twin screw extruders operated at about 100 to about 150 rpms and at a temperature of about 300 ° C. The pelletized samples were injection molded into the test plates on a VanDorn using a barrel temperature of about 243 ° C and a mold temperature of about 82 ° C. These test plates were used to determine the physical properties of the polyester resin compositions, particularly with respect to "color difference" and "gloss retention percentage". In this regard, the "color difference" data in the following tables 1 and 2 were obtained by exposing the test plates to ultraviolet light and heating in a Xenon arc meteorological meter that is operated in accordance with the automotive test procedures SAEJ1885.

Conditions SAEJ1885 Light Cycle Darkness Cycle Radiation, W / m2 0.55 Black Panel Temperature, ° C 89 38 Relative Humidity,% 50 95 Cycle Time, Hours 3.8 1.0 The amount of exposure was measured in terms of the total radiation received by the test plates, expressed in kilojoules per square meter (kJ / m2). The degree of color change was determined instrumentally by measuring the color of the specimens exposed against the color of the unexposed specimen, the degree of color change was quantified as the total color difference (delta E *), calculated in all cases for illuminator "D-65", observer of 10 degrees, including specular, expressed in CIELab units, in accordance with ASTM D-2244. When the values L, a and b of the Hunter colorimetric system are measured and the color difference value, E of the polyester composition of the invention can be calculated from the equation:? E = [(L- 2 + (aa, ) 2 + (b-b0) where Lo, ao and bo are measured values of the color before radiation and L, a and b are the measured values after the radiation, and where L = L-Lo is the difference in luminosity and darkness between the exposed and unexposed samples, ya = a-ao is the difference between the red and green of the exposed and unexposed samples, and b = b-bo is the difference in the yellowish and bluish of the exposed samples and not exposed.The "gloss retention percentage" (60% brightness) is determined by measuring the 60 degree brightness of the test plates before and after exposure to the Xenon arc weather meter using a multi brightness meter -Garner angle operated in accordance with ASTM 523. Therefore, the brightness retention of each of the test plates was obtained by dividing the brightness measurement of the exposed specimen between the brightness measurement of the unexposed specimen, with the resulting number expressed as a percentage.

EXAMPLE 1 Various amounts of stabilizer system components were incorporated into a polyester resin, characterized by containing about 25 p% polybutylene terephthalate, about 15 p% copolyester elastomer, about 30 p% olefinic elastomer, about 30 p% MBS, approximately 0.1 p% of Irganox 1010, and approximately 0.2 p% of Irgaphos. Samples 1 to 16 were prepared by mixing the amount of components, measured in grams, according to the above procedure. The colorant MC3123K20 39292-04-21 was used, in addition to a number of ultraviolet light absorbers and HALS to prepare the sample.

SAMPLE 1 Polyester 2000.0 g MC3123K20 39292-04-21 00.0 g SAMPLE 2 Poliéste r 1979.0 g MC3123K20 39292-04-21 00.0 g Cyasorb UV5411 0.5 g Sanol LS770 10.5 g SHOW 3 Polyester 1979.0 g MC3123K20 39292-04-21 100.0 g Cyasorb UV5411 10.5 g Hostavin N20 10.5 g SAMPLE 4 Polyester 1979.0 g MC3123K20 39292-04-21 100.0 g Cyasorb UV5411 10.5 g Hostavin N30 10.5 g SHOW 5 Polyester 1979.0 g MC3123K20 39292-04-21 100.0 g Cyasorb UV5411 10.5 g Adkastab LA63 10.5 g SAMPLE 6 Polyester 1979.0 g MC3123K20 39292-04-21 100.0 g Sanol LS770 10.5 g Tinuvin 234 10.5 g SAMPLE 7 Polyester 1979.0 g MC3123K20 39292-04-21 100.0 g Sanol LS770 10.5 g Cyasorb UV531 10.5 g SHOW 8 Polyester 1968.50 MC3123K20 39292-04-21 100.0 g Cyasorb UV5411 10.5 g Sanol LS770 10.5 g SAMPLE 9 Polyester 1968.5 g MC3123K20 39292-04-21 100.0 g Cyasorb UV5411 10.5 g Sanol LS770 10.5 g Irganox 1010 10.5 g SHOW 10 Polyester 1968.5 g MC3123K20 39292-04-21 100.0 g Cyasorb UV5411 10.5 g Sanol LS770 10.5 g Sandostab P-EPQ 10.5 g SAMPLE 11 Polyester 1968.5 g MC3123K20 39292-04-21 100.0 g Cyasorb UV5411 10.5 g Sanol LS770 10.5 g Sandostab P-EPQ 10.5 g SAMPLE 12 Polyester 1978.9 g MC3123K20 39292-04-21 100.0 g Cyasorb UV5411 10.5 g Sanol LS770 5.3 g Hostavin N30 5.3 g SAMPLE 13 Polyester 1968.5 g MC3123K20 39292-04-21 100.0 g Cyasorb UV5411 10.5 g Sanol LS770 10.5 g Hostavin N30 10.5 g SHOW 14 Polyester 1968.5 g MC3123K20 39292-04-21 100.0 g Cyasorb UV5411 10.5 g Hostavin N20 5.3 g Hostavin N30 5.3 g SHOW 15 Polyester 1968.5 g MC3123K20 39292-04-21 100.0 g Cyasorb UV5411 10.5 g Hostavin N20 5.3 g Hostavin N30 5.3 g Sandostab P-EPQ 10.5 g SAMPLE 16 Polyester 1947.5 g MC3123K2029292-04-21 100.0 g Cyasorb UV5411 21.0 g Sanol LS770 10.5 g Hostavin N30 10.5 g Sandostab P-EQP 10.5 g Test plates prepared for these compositions were exposed to a Xenon arc meteorological meter in accordance with the SAE patent J1885 as described above, the resulting data shown in table 1 as the "color difference", delta E * . Generally, the higher the measured color change, the more visually refutable the test appears. As can be seen in Table 1, the color difference after exposure ranged from a minimum of about 2.16 for sample 16 to a maximum of about 3.31 for control without UV stabilizers (Sample 1). The new and unexpected results of the molding composition is that the samples containing a low molecular weight, monomeric HALS (ie Sanol LS770 or Hostavin N20) generally showed higher surface brightness values similar or greater than those of the pattern control, Sample 1. This unexpected increase in brightness was not completely expected and visually is more doubtful. Only samples 4 and 5, which did not contain any of these additives, visually appeared to show a minor complete appearance change compared to the control, Sample 1. Specifically, Sample 4 containing Hostavin N30, HALS oligoes showed the most visual change low and therefore the best stability.

TABLE 1 Hues ra No. 1 2 3 4 5 6 7 8 Polyester resin 95.24% 94.24 94.24 94.24 94.24 94.24 94.24 93.7 Coloring 4.76 4.76 4.76 4.76 4.76 4.76 4.76 4.7 Cyasorb UV5411 0.50 0.50 0.50 0.50 0.7 Sanol LS770 0.50 0.50 0.50 0.7 Hostavin N20 0.50 Hostavin N30 0.50 Adkastab LA63 0.50 Tinuvin 234 0.50 Cyasorb UV 531 0.50 Delta E * 6601.6 kJ /? 2 3.31 2.63 2.96 2.66 2.95 2.57 3.06 2.3 Delta L * -2.43 -1.78 -1.95 -1.72 -2.21 -1.93 -2.12 -1.5 Delta b * 2.24 1.93 2.23 2.02 1.95 1.69 2.21 1.7 60 * Brightness (%) 8.0 8.3 8.6 4.3 4.0 8.0 7.4 6.1 TABLE 1 (CONTINUED) Sample No. 9 10 11 12 13 14 15 16 Polyester resin 93.74 93.74 93.24 94.24 93.74 94.24 93.74 92.74 Coloring 4.76 4.76 4.76 4.76 4.76 4.76 4.76 4.76 Cyasorb UV5411 0.50 0.50 0.50 0.50 0.50 0.50 0.50 1.00 Sanol LS770 0.50 0.50 0.50 0.25 0.50 0.50 Hostavin N20 0.25 0.25 Hostavin N30 0.25 0.50 0.25 0.25 0.50 Adkastab LA63 Tinuvin 234 Cyasorb UV 531 Irganox 1010 0.50 0.50 Sandostab P-EPQ 0.50 0.50 0.50 0.50 Delta E * § 601.6kJ /? 2 2.79 2.47 2.51 2.61 2.89 3.01 2.38 2.16 Delta L * -1.80 -1.50 -1.33 -1.64 -1.98 -2.14 -1.46 -1.29 Delta b * 2.13 1.96 2.12 2.03 2.11 2.12 1.88 1.73 60 * Brightness. { %) 8.3 11.8 12.5 8.5 9.3 7.9 8.7 7.1 Another surprising and unexpected result was the type of ultraviolet light absorber that had virtually no effect on the UV function of the resin. Samples 2, 6 and 7 contained low molecular weight benzotriazole (Cyasorb UV5411), higher molecular weight benzotriazole (Tinuvin 234), and benzophenone (Cyasorb UV 5311), respectively. The ultraviolet light function of these three samples was virtually identical both visually and when measured by color difference and change in brightness.

EXAMPLE 2 This group of samples were prepared and tested for further investigation of the effects of the stabilizing components against hindered amine light in the UV stability of the polyester polymer system. In this example several monomeric and polymeric / oligomeric hindered amines were evaluated to better understand the effects of the primarily molecular weight on the UV function of the total resin system. In addition, several substituted portions in the structure of HALS were studied. As in Example 1, in Example 2 UV stabilizer samples were prepared using Vandar® 9118 natural thermoplastic polyester, a dye, RC3097K20 and (except Sample 17) several portions of the stabilizer system. The Vandar® 9118 polyester thermoplastic resin, purchased from Hoechst Celanese Corporation, Hoechst Technical Polymers, Summit, NJ 07901, contains almost 60% by weight of polyester, about 40% by weight of an MBS modifier, almost 0.1% by weight of Irganox B215, about 0.2% by weight of Irgaphos 168, and almost 0.5% by weight of Sandostab P-EPQ.

SAMPLE 17 polyester 2000.0 g RC3097K20 100. Og SHOW 18 polyester 1979 g RC3097K20 100.0 g Cyasorb UV5411 10.5 g Hostavin N30 10.5 g SAMPLE 19 polyester 1947.5 RC3097K20 100 Cyasorb UV5411 42 Hostavin N30 10.5 SAMPLE 20 Polyester 1947.5 RC3097K20 100 Cyasob UV5411 10.5 Hostavin N30 42 SAMPLE 21 polyester 1947.5 RC3097K20 100 Cyasob UV5411 26.3 Hostavin N30 26.3 SAMPLE 22 polyester 1916 RC3097K20 100 Cyasob UV5411 42 Hostavin N30 42 SAMPLE 23 1916 polyester RC3097K20 100 Hostavin N30 42 Tinuvin 234 42 SAMPLE 24 polyester 1979 RC3097K20 100 Cyasob UV5411 10., 5 Tinuvin 144 10., 5 SAMPLE 25 polyester 1947., 5 RC3097K20 100 Cyasob UV5411 42 Tinuvin 144 10., 5 SAMPLE 26 1947 polyester., 5 RC3097K20 100 Cyasob UV5411 10., 5 Tinuvin 144 42 SAMPLE 27 polyester 1947.4 RC3097K20 100 Cyasob UV5411 26.3 Tinuvin 144 26.3 SAMPLE 28 polyester 1916 RC3097K20 100 Cyasob UV5411 42 Tinuvin 144 42 SAMPLE 29 1916 polyester RC3097K20 100 Tinuvin 144 42 Tinuvin 144 42 SAMPLE 30 20 polyester 1979 RC3097K20 100 Cyasorb UV5411 10.5 Good rite 3150 10.5 SAMPLE 31 Polyester 1947.5 RC3097K20 100 Cyasorb UV5411 42 Good ri e 3150 10.5 SAMPLE 32 polyether 1947.5 RC3097K20 100 Cyasorb UV5411 10.5 Good ri e 3150 42 SAMPLE 33 Polyester 1947.4 RC3097K20 100 Cyasorb UV5411 26.3 Good rite 3150 26.3 SAMPLE 34 1916 polyester RC3097K20 100 Cyasorb UV5411 42 Good rite 3150 42 SAMPLE 35 polyester 1916 RC3097K20 100 Goodrite 3150 42 Tinuvin 234 42 SAMPLE 36 Polyester 1979 RC3097K20 100.0 Cyasorb UV5411 41.5 Adkastab LA63 10.5 SAMPLE 37 1979 polyester RC3097K20 100.0 Cyasorb UV5411 42.0 Adkastab LA63 10.5 SAMPLE 38 25 polyester 1947.5 RC3097K20 100.0 Cyasorb UV5411 41.5 Adkastab LA63 10.5 SAMPLE 39 Polyester 1947.5 RC3097K20 100.0 Cyasorb UV5411 41.5 Adkastab LA63 42.0 SAMPLE 40 1947 polyester. 5 RC3097K20 100 Cyasorb UV5411 26.3 Adkastab LA63 26.3 SAMPLE 41 20 polyester 1916.0 RC3097K20 100 Cyasorta UV5411 42.0 Adkastab LA63 42.0 SAMPLE 42 polyester 1916.0 RC3097K20 100 Adkastab LA63 42.0 Tinuvin 234 42.0 Table 2 below provides the percentages by weight, based on 100 percent by weight of the sample, of the sample components.

TABLE 2 Description of the ingredient 17 18 19 20 21 22 23 Polyester resin r 95.24% 94.24 92.74 92.74 92.74 91.24 91.24 Coloring 4.76 4. 76 4. 76 4 .76 4. 76 4.76 4.76 Cyasorb UV5111 0.50 2. 00 0. 50 1.25 2.00 Hostavin N30 0.50 0.50 2.00 1.25 2. 00 2.00 Tinuvin 234 2.00 Delta E * © 601.1 3.93 3.70 2.79 2.07 1.76 1.89 2.23 kJ / m2 Delta L * -2.39 -1.65 -1.06 -1.01 -1.01 -1.45 -1.84 Delta b * 2.99 3.31 2.57 1.79 1.41 1.19 1.26 60 ° Brightness (%) 3.2 6.4 6.1 25.9 12.8 7.9 9.2 TABLE 2IC0NTINUATION) Description of the ingredient 24 25 26 27 28 29 Polyester resin 94.24% 94.24 92.74 92.74 92.74 91.24 Coloring 4.76 4.76 4.76 4.76 4.76 4.76 Cyasorb UV55411 0.50 2.00 0.50 1.25 2.00 Tinuvin 144 0.50 0.50 2.00 1.25 2.00 2.00 Tinuvin 234 2.00 Delta E * 0601.6 1.90 1.35 2.87 2.47 1.34 0.87 kJ / m2 Delta L * -0.69 -1.00 -2.36 -2.11 -0.97 -0.50 Delta b * 1.74 0.87 1.61 1.25 0.89 0.63 60th Brightness (%) 21.4 12.5 7.2 6.8 7.78 6.7 TABLE 2CC0NTINUACION) Description of the ingredient 30 31 32 33 34 35 Polyester resin 94.24% 92.74 92.74 92.74 91.24 91.24 Coloring 4.76 4.76 4.76 4.76 4.76 4.76 Cyasorb UV55411 0 0..5500 2.00 0.50 1.25 2.00 Good-Rite 3150 0 0..5500 0.50 2.00 1.25 2.00 2.00 Tinuvin 234 2.00 Delta E * © 601.6 1.35 1.43 1.76 1.21 0.52 0.62 kJ / m2 Delta L * -0.21 -1.23 -1.40 -0.88 -0.08 -0.05 Delta b * 1.27 0.62 1.01 0.75 0.45 0.51 60th Brightness (%) 18.8 5.2 5.6 6.5 5.5 5.6 TABLE 2IC0NTINUACI0N Description of the ingredient 36 37 38 39 40 41 Polyester resin 94.24% 92.74 92.74 92.74 91.24 91.24 Coloring 4.76 4.76 4.76 4.76 4.76 4.76 Cyasorb UV55411 0.50 2.00 0.50 1.25 2.00 Adkastab LA - 63 0.50 0.50 2.00 1.25 2.00 2.00 Tinuvin 234 2.00 Delta E * 601.6 2.33 1.51 1.93 1.56 1.76 1.86 kJ / m2 Delta L * -0.86 -1.17 -1.45 -1.27 -1.54 -1.65 Delta b * 2.14 0.93 1.24 0.87 0.83 0.85 60th Brightness (%) 11.5 15.5 19.4 14.2 3.8 3.9 It was determined that Hostavin N30 and Adkstab LA-63 (from Table 2, samples 20 and 21), continued to perform well. In addition, Tinuvin 144 with its portion of hindered phenolic antioxidant and Goodrite 3150 with its triazine portion also worked well. These four (4) HALS compounds were also evaluated to study the effects of their concentration in terms of stability. The results of Table 2 confirm that a higher molecular weight of the HALS compounds and / or those that are highly substituted are the keys to achieving good stability against ultraviolet light of the polyester resins. In addition, an unexpected result for this experiment was the effect of the polymeric / oleic HALS concentration and the ratio of the UV absorber to the increase in surface brightness. Samples 18 and 19 with low polymer / olimeric HALS levels, Hostavin N30 did not show any increase in brightness. The sample 20, with a high polymeric / olimeric HALS level, showed a very substantial increase in brightness. However, using the polymeric / olimeric HALS at a 1: 1 ratio with a UV absorber, even at a higher level of HALS, eliminated this increase in surface brightness. Samples 22, 28, 34 and 40 passed all exposure requirements of 601.6 kJ / m2. This was evident when measuring the values of the low color change (E *) and no significant increase in surface brightness.

Claims

NOVELTY OF THE INVENTION CLAIMS

1. - A stabilized ultraviolet light molding composition, consisting of a polyester thermoplastic resin and a UV stabilizer system with said polyester resin in an effective amount sufficient to achieve a color difference, as calculated in CIELab units under illuminant "D-65" in accordance with ASTM D-2244, of less than nearly 2.25 when exposed to a irradiation of 601.6 kJ / m2 in a Xenon arc meteorological meter operated in accordance with SAE J1885, and said composition shows a retention of the surface brightness after irradiation of at least 7.5%, in which said UV stabilizer system consists of (i) an ultraviolet light absorber; ii) a hindered amine light stabilizer; and iii) an antioxidant.

2. A composition according to claim 1, further characterized in that the thermoplastic polyester was selected from a group consisting of linear polyalkylene terephthalates, copolyester elastomers, polycarbonates and mixtures thereof.

3. A composition according to claim 2, further characterized in that the linear polyalkylene terephthalate was selected from a group consisting of polybutylene terephthalate, polypropylene terephthalate, polyethylene terephthalate and ethylene-1,4-cyclohexylanodimethylene terephthalate.

4. A composition according to claim 3, further characterized in that the copolyester elastomer is a copolyester.

5. The composition according to claim 4, wherein the thermoplastic polyester is a mixture of 0 to almost 30% by weight of polybutylene terephthalate, from about 35 to 70% by weight of polyester eslastomer, from 0 to almost 30% by weight of polycarbonate from almost 10 to almost 50% by weight of MBS, and from about 0.2 to almost 1.0% by weight of an antioxidant, based on the total weight of the composition.

6. The composition according to claim 5, wherein the stabilizing system against UV light is present in an amount of almost 0.5 to about 5.0% by weight, based on the total weight of the composition.

7. The composition according to claim 6, characterized in that the stabilizer against UV light is present in an amount of almost 0.1 to almost 2.0% by weight, based on the total weight of the composition.

8. The composition according to claim 7, further characterized in that the hindered amine is present in an amount of almost 0.1 to almost 2.0% by weight, based on the total weight of the composition.

9. The composition according to claim 8, further characterized in that the relative ratio of hindered amine with respect to the ultraviolet light absorber is approximately 1: 1 to almost 1: 2, respectively.

10. The composition according to claim 9, further characterized in that the antioxidant is present in an amount from about 0.1 to about 1.0% by weight, based on the total weight of the composition.

11. The composition according to claim 10, further characterized in that the UV light absorber is a benzophenone selected from a group consisting of 2,4-dihydroxybenzophenone; 2-hydroxy-4-methoxybenzophenone; 2-hydroxy-4-terbutoxybenzophenone; 2-hydroxy-4-octoxybenzophenone; 2-hydroxy-4-dodecylcloxybenzophenone; M 2 -hydroxy-4-stearoxybenzophenone; 2-hydroxy-4-phenoxybenzophenone; 2-hydroxy-4 - (& -hydroethoxy) benzophenone; 2-hydroxy-4- (2'-hydroxy-3 ') -acyloxypropoxy) benzophenone; 2-hydroxy-4- (2'-hydroxy-3'-methacryloxypropoxyl) benzophenone; 2-hydroxy-4- (2'-hydroxy-3'-methacryloxypropoxyl) benzophenone; 2,2'-dihydroxybenzophenone; 2,2'-dihi roxi -4 -me toxibenzophenone; 2,2'-dihydroxy-4-butoxiobenzophenone; 2,2'-dihydroxy-4-octoxybenzophenone; 2,2'-dihydroxy-4-lauroxy benzophenone; 2,2 ', 4,4'-tetrahydroxybenzophenone; 2,2 ', 4-trihydro-4-methoxybenzophenone; 2-hydroxy-4-methoxy-4'-chlorobenzophenone; 2,2'-dihydroxy-4,4'-dimethyloxybenzophenone; 2-hydroxy-4-methoxy-2'-methyl-4'-hydroxybenzophenone; 2-hydroxy-4-methoxy-4 '-tert-butylbenzophenone; 2-hydroxy-4-methoxy-4'-methyl-benzophenone; 2-hydroxy-4,4'-dimethoxybenzophenone; 2-hydroxy-4,4 ', 2'-trimethoxybenzophenone; and 2-hydroxy-4-N-octoxybenzophenone.

12. The stabilizing system against UV light according to claim 11, characterized in that the UV light absorber is a benzotriazole selected from a group consisting of 2- (2'-hydroxy-5'-methylphenyl) benzotriazole; 2- (2'-hydroxy-3'-5'-di-tert-butylphenyl) benzo riazole; 2- (2'-hydroxy-3'-5'-di-tert-butylphenyl) -5-chlorobenzotriazole; 2- (2'-hydroxy-3 ', 5'-di-phenyl-) - 5-benzothiazole; 2- (2 '-hydroxy-3'-tert-butyl-5'-methylphenyl) -5-chlorobenzotriazole; 2- (2 '-hydroxy-5'-terbutyl-5' -methylphenyl) benzothiazole; 2- (2 '-hi-roxy -3' -secbutyl-5'-te-butyl phenyl) benzothiazole; 2- (2'-Hydroxy-5-t-octylphenyl) benzotriazole; 2- (2H-benzotriazol-2-yl) -4,6-bis (l-methyl-l-phenylethyl) -phenol; and 2- (3 ', 5' -bis) l-methyl-l-phenylethyl) -2'-hydroxy phenyl) benzo triazole.

13. The composition according to claim 12, further characterized in that the hindered amine light stabilizer was selected from a group consisting of 1,1'-Cl, 2-ethanediyl] -bis [3, 3.5, 5-tetraethylpoperazione]; polymer of di-ethylsuccinate with 4-hydroxy-2,2,6,6-tetramethyl-1-piperdino ethanol; bis (1, 2,2,6,6-pentamethyl-4-piperdinyl) -sebacate; bis [2, 2, 6, 6-e-ramethyl-4-piperidinyl] decandazole; bis (l, 2,2,6,6-pentamethyl-4-pipe ridi ni 1) -2- [[3,5-bis (l, 1-dimethylethyl) -4-hydroxy phenyl] me ti l] -2 -butyl propane; poly [(2,2,6,6-tetramethyl-4-piperidinyl) iminomethylene (2,2,6,6-tetramethyl-4-piperidinyl) imino [6 (octylamino) -l, 3,5-triazine-4, 2-diyl]]; 2,2,6,6-tetramethyl-4-piperidinyl benzoate; tetrakis (2, 2,6,6-tetramethyl-4-piperidinyloxy) silane; bis (1, 2,2,6,6-pentamethyl-4-piperidinyl) - (3,5-di-tert-butyl-4-hydroxybenzyl) butylpropanedioate; Polymeric imidates / molten higher oligomeric amines; 2,2,6,6-tetramethylpiperidine; Goodrite 3150; and [1, 2,2,6,6-pentamethyl-4-piperidyl / &;, β, β ', & -tetramethyl-3,9- (2,4,8,10-tet raoxaspi ro (5, 5) undecane) diethyl 1] -1, 2, 3, 4-bu tantet raca rboxi lato.

14. The composition according to claim 13, further characterized in that the antioxidant is selected from a group consisting of tetrakis [methylene (3,5-di-t-butyl-4-hydroxyhydrocinnamate)] methane and [tetrakis (2 , 4-di-tert-butylphenyl) 4,4-biphenyldiphosphonyl].

15. The composition according to claim 14, further comprising an impact modifier.

16. The composition according to claim 15, further characterized in that the molding composition is suitable for the preparation of molded parts suitable for UV light environments.

17. A molding composition stabilized against ultraviolet light, consisting of a thermoplastic polyester consisting of from 0 to almost 30% by weight of polyalkylene terephthalate, from about 55 to almost 65% by weight of polyester elastomer, from 0 to 50% by weight. to almost 15% by weight of polycarbonate, from almost 15 to almost 45% by weight of MBS and from about 0.2 to almost 0.8% by weight of the antioxidant; and a stabilizing system against UV light in combination with said polyester in an effective amount sufficient to achieve a color difference, as calculated in CIELab units under illuminant "D-65" in accordance with ASTM D-2244, of almost 2.16 when exposed to a irradiation of 601.6 kJ / m2 in a Xenon arc meteorological meter operated in accordance with SAE J1885, and said composition shows a retention of the surface brightness after irradiation of about 7.1%, wherein said stabilization system consists of: (i) from about 0.5 to about 5.0% by weight of an ultraviolet light absorber selected from a group consisting of benzothiazoles and benzophenones; (ii) from about 0.5 to about 5.0% by weight of a hindered amine light stabilizer selected from a group consisting of 1, l '- [1,2-ethanediyl] -bis [3, 3,5,5-tetramethylpoperazione] ]; polymer dimethylsuccinate with 4-hydroxy-2,2,6,6-tetramethyl-1-piperidine ethanol; bis (l, 2,2,6,6-pentamethyl-4-piperidinyl) -sebacerate, bis [2, 2, 6,6-t-tramethyl-4-piperidinyl-jdecanthioate; bis (1, 2,2,6,6-pentamethyl-4-piperidinyl) -2- [[3,5-bis (1, 1-dimethylethyl) -4-hydroxyphenyl] methyl] -2-butylpropanedioate; poly [(2,2,6,6-tet ramethi 1-4 -pipe ridinyl) imi nomethylene (2, 2, 6,6-tetramethyl-4-piperidinyl) imino [6 (octylamino) -l, 3, 5-triazine-4,2-diyl]]; 2,2,6,6-tetramethyl-4-piperidinyl benzoate; tet rachis (2, 2,6,6-tetramethyl-4-piperidinyloxy) silane; bis (1, 2,2,6,6-pentamethyl-4-piperidinyl) - (3,5-di-tert-butyl-4-hydroxybenzyl) butyl propanedioate; Polymeric imidates / molten higher oligomeric amines; 2,2,6,6-tetramethylpiperidine; Good rite 3150; and [1, 2,2,6,6-pentamethyl-4-piperidyl / &; & amp; & - & ' -tetrame ti 1-3, 9- (2, 4, 8,10-tet raoxaspi ro (5, 5) undecano) diethyl] -1,2,3,4-butanetetracarboxylate; and (iii) from about 0.1 to about 1.0% by weight of an antioxidant selected from a group consisting of tetrakis [methylene (3,5-di-t-butyl-4-hydroxyhydrocinnamate)] methane and [tetrakis (2.4 -di-tert-butylphenyl) 4,4-biphenyldiphosphonyl].

18. The composition according to claim 17, further characterized in that the benzophenone was selected from the group consisting of 2,4-dihydroxybenzophenone; 2-hydroxy-4-methoxybenzophenone; 2-hydroxy-4-terbutoxybenzophenone; 2-hydroxy-4-octoxybenzophenone; 2-hydroxy-4-dodecycloxybenzophenone; 2-hydroxy-4-stearoxybenzophenone; 2-hydroxy-4-phenoxybenzophenone; 2-hydroxy-4- (β-hydroxyethoxy) benzophenone; 2-hydroxy-4- (2 '-hydroxy-3'-acryloxypropoxy) benzophenone; 2-hydroxy-4- (2'-hydroxy-3'-methacryloxypropoxyl) benzophenone; 2,2'-dihydroxybenzophenone; 2,2'-dihydroxy-4-me oxybenzophenone; 2,2'-dihydroxy-4-butoxybenzophenone; 2,2'-dihydroxy-4-octoxybenzophenone; 2,2'-dihydroxy-4-lauroxybenzophenone; 2,2 ', 4,4'-tetrahydroxybenzophenone; 2,2 ', 4' -trihydro-4-methoxybenzophenone; 2-hydroxy-4-methoxy-4'-chlorobenzophenone; 2,2'-dihydroxy-4, '-dimethyloxybenzophenone; 2-hydroxy-4-methoxy-2'-methyl-4'-hydroxybenzophenone; 2-hydroxy-4-methoxy-4'-tert-butylbenzophenone; 2-hydroxy-4-methoxy-4'-methyl-benzophenone; 2-hydroxy-4,4'-dimethoxybenzophenone, 2-hydroxy-4,4 ', 2'-rimethoxybenzophenone; and 2-hydroxy-4-N-octoxybenzophenone.

19. The composition according to claim 18, further characterized in that the benzotriazole was selected from a group consisting of 2- (2'-hydroxy-5'-methyl phenyl) benzothiazole, 2- (2'-) hydroxy -3'-5'-di-te-butyl phenyl) benzothiazole; 2- (2'-hydroxy-3'-5'-di-tert-butylphenyl) -5-chlorobenzotriazole; 2- (2 '-hydroxy-3', 5 '-diphenyl-) - 5-benzo-riazole; 2- (2'-Hydroxy-3'-tert-butyl-5'-methyl phenyl) -5-triazole robenzo; 2- (2 '-hydroxy-5'-terbutyl-5' -methylphenyl) benzotriazole; 2- (2 '-hydroxy-3' -secbutyl-5 '-te rbuyl phenyl) benzothiazole; 2-) 2 '-hydroxy-5-tert-octylphenyl) benzotriazole; 2- (2H-benzotriazol-2-yl) -4,6-bis (l-methyl-l-phenylethyl) -phenyol; and 2- (3 '-5'-bis (l-methyl-l-phenylethyl) -2'-hydroxy phenyl) benzothiazole.

20. The composition according to claim 19, further comprises an impact modifier.

21. The composition according to claim 20, further characterized in that the molding composition is suitable for the preparation of mold parts suitable for UV light environments.

22. A molding composition stabilized against ultraviolet light, consisting of a thermoplastic polyester consisting of 0 to almost 25% by weight of polyalkylene terephthalate, of about 60% by weight of polyester elastomer, from 0 to almost 10 % by weight of polycarbonate, from almost 20 to almost 40% by weight of MBS and of about 0.6% by weight of the antioxidant; and a stabilizing system against UV light in combination with said polyester in an effective amount sufficient to achieve a color difference, as calculated in CIELab units under illuminant "D-65" in accordance with ASTM D-2244, of almost 2.16 when exposed to a irradiation of 601.6 kJ / m2 in a Xenon arc meteorological meter operated in accordance with SAE J1885, and said composition shows a retention of the surface brightness after irradiation of about 7.1%, wherein said stabilization system consists of: (i) from about 0.5 to about 5.0% by weight of an ultraviolet light absorber selected from a group consisting of 2,4-dihydroxybenzophenone; 2-hydroxy-4-methoxybenzophenone; 2-hydroxy-4-terbutoxybenzophenone; 2-hydroxy-4-octoxybenzophenone; 2-hydroxy-4-dodecyloxybenzophenone; 2-hydroxy-4-stearoxybenzophenone; 2-hydroxy-4-phenoxybenzophenone; 2-hydroxy-4- (β-hydroxyethoxy) benzophenone; 2-hydroxy-4- (2'-hydroxy-3'-acryloxypropoxy) benzophenone; 2-hydroxy-4- (2'-hydroxy-3'-methacryloxypropoxyl) benzophenone; 2,2'-dihydroxybenzophenone; 2,2'-dihydroxy-4-methoxybenzophenone; 2,2'-dihydroxy-4-butoxybenzophenone; 2,2'-dihydroxy-4-octoxybenzophenone; 2,2'-dihydroxy-4-lauroxybenzophenone; 2,2 ', 4,4'-tetrahydroxbenzophenone; 2,2 ', 4' -trihydro-4-methoxybenzophenone; 2-hydroxy-4-methoxy-4'-chlorobenzophenone; 2,2'-dihydroxy-4,4'-dimethyloxybenzophenone; 2-hydroxy-4-methoxy-2'-methyl-4 '-hydroxybenzophenone; 2-hydroxy-4-methoxy-4'-tert-butylbenzophenone; 2-hydroxy-4-methoxy-4'-methyl-benzophenone; 2-hydroxy-4,4'-dimethoxybenzophenone; 2-hydroxy-4,4'-2'-tri-ethoxybenzophenone; 2-hydroxy-4-N-octoxybenzophenone; 2- (2'-hi roxy-5'-methylphenyl) benzothiazole; 2- (2'-Hydroxy-3'-5'-di-tert-butylphenyl) benzothiazole; 2- (2 '-hydroxy -3'-5'-di-tert-butylphenyl) -5-chlorobenzotriazole; 2- (2 '-hydroxy-3', 5 '-diphenyl-) -5-benzo triazole; 2- (2'-Hydroxy-3'-tert-butyl-5'-methyl phenyl) -5-cyclobenzoate triazole; 2- (2 '-hydroxy-5' -terbutyl-5 '-methyl phenyl) benzo triazole; 2- (2 '-hydroxy -3' -secbuti 1-5 '-te rbutyl phenyl) benzothiazole; 2- (2'-Hydroxy-5-tert-octyl phenyl) benzo triazole; 2- (2H-benzotriazol-2-yl) -4,6-bis (l-methyl-l-phenylethyl) -phenyol; and 2- (3 ', 5'-bis (l-methyl-l-phenylethyl) -2'-hydroxyphenyl) benzotriazole; (ii) from about 0.5 to about 5.0% by weight of a hindered amine light stabilizer selected from a group consisting of 1,1 '- [1,2-ethanediyl] -bis [3,3,5,5-tetramethylpoperazione] ]; polymer dimethylsuccinate with 4-hydroxy-2,2,6,6-tetramethyl-1-piperdine ethanol; bis (1, 2,2,6,6-pentamethyl-4-piperdinyl) -sebacate; bis [2, 2,6, -tetramethyl-4-piperidinyl] decanedioate; bis (1, 2,2,6,6-pentamethyl-4-piperidinyl) -2 - [[3,5-bis (1,1-dimethyl) -4-hydroxyphenyl] methyl] -2-butyl propanedioate; poly [(2,2,6,6-tetramethyl-4-piperidinyl) iminomethylene (2,2,6,6-tetramethyl-4-piperidinyl) amino] [6 (octalamino) -l, 3,5-triazine-4 , 2-diyl]]; 2,2,6,6-tetramethyl-4-piperidinyl benzoate; tetrakis (2,2,6,6-tetramethyl-4-piperidinyloxy) silane; bis (1, 2,2,6,6-pentamethyl-4-piperidinyl) - (3,5-di-tert-butyl-4-hydroxybenzyl) butyl propanedioate; melted hindered polymeric / oligomeric higher amines; 2,2,6,6-tetamethylpiperidine; Good rite 3150; and [1, 2,2,6,6-pentamethyl-4-piperidyl / &;, β, β ', & -tet ramethyl-3,9- (2,4,8, lot traoxaspi ro (5, 5 = undecano) = die ti 13-1,2, 3,4-butanotetracarboxylate, and (iii) from almost 0.1 to almost 1.0 % by weight of an antioxidant selected from the group consisting of tetrakismethylene (3,5-di-t-butyl-4-hydroxyhydrocinnamate) 3 methane and Ctetraquis (2,4-di-tert-butylphenyl) 4,4-biphenyldiphosphonyl], in which mold composition is suitable for the preparation of mold parts suitable for UV light environments 23.- A UV stabilizing system suitable for thermoplastic polyester resin compositions consisting of: (i) of about 0.5 at about 5.0% by weight of an ultraviolet light absorber selected from the group consisting of 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-terbutoxybenzophenone, 2-hydroxy-4-octoxybenzophenone, 2-hydroxy -4-dodecycloxybenzophenone, 2-hydroxy-4-stearoxybenzophenone, 2-hydroxy-4-phenoxybenzophenone, 2-hydroxy-4- (β-hydroxyethoxy) benzophenone, 2-hydroxy-4- (2'-hydroxy-3'-acryloxypropyl) xi) benzophenone; 2-hydroxy-4- (2'-hydroxy-3'-methacryloxypropoxyl) benzophenone; 2,2'-dihydroxybenzophenone; 2,2'-dihydroxy-4-methoxybenzophenone; 2,2'-dihydroxy-4-butoxybenzophenone; 2,2'-dihydroxy-4-octoxybenzophenone; 2,2'-dihydroxy-4-lauroxybenzophenone; 2,2 ', 4,4'-tetrahydroxybenzophenone; 2,2 ', 4' -trihydro-4-methoxybenzophenone; 2-hydroxy-4-methoxy-4'-chlorobenzophenone; 2,2'-dihydroxy-4,4'-dimethyloxybenzophenone; 2-hydroxy-4-methoxy-2'-methyl-4 '-hi roxybenzophenone; 2-hydroxy-4-methoxy-4'-tert-butylbenzophenone; 2-hydroxy-4-methoxy-4'-ethyl-benzophenone; 2-hydroxy-4,4'-dimethoxybenzophenone; 2-hydroxy-4,4 ', 2'-trimethoxybenzophenone; 2-hydroxy-4-N-octoxybenzophenone; 2- (2 '-hydroxy-5' -methylphenyl) benzotriazole; 2- (2 '-hydroxy-3' -5'-di-tert-butylphenyl) benzothiazole; 2- (2 '-hydroxy-3' -5 '-di-tert-butyl phenyl) -5-chlorobenzothiazole; 2- (2 '-hydroxy-3', 5 '-diphenyl-) -5-benzo triazole; 2- (2 '-hydroxy-3'-tert-butyl-5' -methyl-1-phenyl) -5-chloro-benzo-triazole; 2- (2 '-hydroxy-5' -terbutyl-5 '-methylphenyl) benzotriazole; 2- (2'-hydroxy-3 '-secbutyl-5' -terbutylphenyl) benzotriazole; 2- (2 '-hydroxy-5-ter-oc-phenyl) benzo triazole; 2- (2H-benzotriazol-2-yl) -4,6-bis (l-methyl-l-phenylethyl) -phenyol; and 2- (3'-5'-bis (l-methyl-l-phenylethyl) -2'-hydroxyphenyl) benzotriazole; (ii) from about 0.5 to about 5.0% by weight of a hindered amine light stabilizer selected from a group consisting of 1,1 '- [1,2-ethanediyl] -bis [3,3,5,5-tetramethylpoperazione] ]; polymer dimethylsuccinate with 4-hydroxy-2,2,6,6-tetramethyl-1-piperdine ethanol; bis (1, 2,2,6,6-pentamethyl-4-piperdinyl) -sebacate; bis [2,6,6,6-ethanol; bis (1, 2,2,6,6-pentamethyl-4-piperdinyl) -sebacate; bis [2,2,6,6-tetramethyl-4-piperidinyl] decanedioate; bis (1, 2,2,6,6-pentamethyl-4-piperidinyl) -2 - [[3,5-bis (1, 1-dimelethyl) -4-hydroxyphenyl] methyl] -2-butylpropanedioate; poly [(2,2,6,6-tetramethyl-4-piperidinyl) iminomethylene (2,2,6,6-te ramethyl-4-piperidinyl) imino [6 (octylami no) -1,3,5-riazine- 4,2-diyl]]; 2,2,6,6-tet ramethyl-4-pi ridinyl benzoate; tetracis (2,2,6, -tetramethyl-4-piperidinyloxy) silane; bis (1, 2,2,6,6-pentamethyl-4-pipe ridinyl) - (3,5-di-te-butyl-4-hydroxybenzyl) butylpropanedioate; higt melt polymeric / oligomeric hindered amines; 2,2,6,6-tetramethylpiperidine; Good rite 3150; and [1,2,2,6,6-tetraoxaspi ro (5,5) undecane) die i 13-1, 2-3,4-butanetetracarboxylate; and (iii) from about 0.1 to about 1.0% by weight of an anti oxidant selected from a group consisting of tetracis [methylene (3,5-di-t-butyl-4-hydroxyhydrocinnamate) 3-methane and [tetracis (2,4- di-tert-butylphenyl) 4,4-biphenyldiphosphonite, further characterized in that the system achieves a color difference, as calculated in CIELab units with "D-65" illuminant in accordance with ASTM Standard D-2244, of almost 2.16 when exposed to an irradiation of 601.6 kJ / m2 in a Xenon arc meteorological meter operated in accordance with SAE J1885, and shows a retention of surface brightness after irradiation of almost 7.1%.