DE102011111621A1 - Polyalkylene glycol di-p-toluates and benzoates, their preparation and their use - Google Patents

Abstract

Compositions of the formulas (I) and (Ia) in which R and R 1 are hydrogen or methyl, R 2 is alkyl and m is 2-6, n is 2-20, p is 1-4 and q is 2-20 and which are the compounds I) or (Ia) contain more than 80 wt .-%, are suitable as plasticizers for plastics and in particular for homo- and copolymers of vinyl chloride.

Description

The invention relates to 4-methylbenzoic acid ω- (p-methylbenzoyl) poly (ω-oxyalkyl) esters, hereinafter also referred to as polyalkylene glycol di-p-toluates, and the corresponding benzoates, their preparation from alkyl p-toluic acid esters or Benzoic acid esters and polyalkylene glycols, their use as plasticizers, and articles, materials and molding compositions containing at least one compound of the type polyalkylene glycol di-p-toluate (4-methylbenzoic acid ω- (p-methylbenzoyl) poly (ω-oxyalkyl) ester).

Polyvinyl chloride (PVC) is one of the most widely used thermoplastic polymers and has been used for decades in the manufacture of soft, flexible articles and rigid molded articles. By adding plasticizers, the properties of PVC can be varied widely. For the most part, phthalic diesters (phthalates) such as di (2-ethylhexyl) phthalate (DEHP), diisononyl phthalate (DINP), diisodecyl phthalate (DIDP), di-n-butyl phthalate (DBP), diisobutyl phthalate (DIBP) and benzyl butyl phthalate (BBP) as plasticizers used.

For applications in the electrical sector, eg. As for cables, increased demands are placed on the permanence of the plasticizer, especially at elevated temperatures. This also applies to applications in the automotive interior, in which outgassing of plasticizers can lead to so-called fogging. For these applications, for example, long-chain phthalates such as diisodecyl phthalate (DIDP), diisoundecyl phthalate (DIUP) or diisotridecyl phthalate (DTDP) or esters of trimellitic acid (TIOTM, TOTM, TINTM) are used. The advantage of lower volatility in using longer alkyl chains, however, comes at the cost of lower compatibility and plasticizer efficiency. For example, when using the less volatile phthalates DINP, DIDP, DIUP or DTDP instead of DEHP, a 6, 10, 16 or even 27% higher amount of plasticizer must be used to set an identical hardness of the PVC composition. When using trimellitates such as TOTM or TINTM, the additional amounts required are in comparable ranges (17% and 27%, respectively).

It is advantageous for the production of soft PVC, if this can be done at low temperatures, as this leads to a saving of energy. In addition, lower processing temperatures allow the use of lower levels of stabilizers, without which thermal processing of PVC would not be possible. By using plasticizers with a good gelling behavior for PVC, its processing can be achieved at low temperatures. The gelling behavior is the plasticizer's ability to penetrate the PVC polymer matrix to reduce the interactions between the polymer chains to produce a softening effect. As a measure of the gelling behavior of a plasticizer, the dissolution temperature for PVC can after DIN 53408 be determined.

In the past, the chronic toxicity of phthalates has been controversial. As a result of these ongoing discussions, certain phthalates may no longer be present in toys intended for the European market. Also in other economic areas such prohibitions are discussed. In addition, the phthalates DEHP, DBP and BBP have been proposed for inclusion in a list of substances of very high concern (SVHC) at the European Chemicals Agency ECHA. The REACH Regulation provides for an authorization procedure for such substances of very high concern, at least resulting in far-reaching information requirements in the supply chain.

Against this background, therefore, the object was to find new plasticizers for plastics, in particular PVC, which have the disadvantages known from the prior art, if possible not or only to a lesser extent. These new plasticizers should preferably have comparable or improved plasticizer properties to the phthalates, have a high enough to meet the high requirements of an application in the electrical sector or automotive interior permanent and can be prepared from inexpensive raw materials. In addition, they should have a good gelling behavior or a low dissolution temperature.

STATE OF THE ART

In addition to the esters of phthalic acid, esters of benzoic acid and p-toluic acid are described in the literature for use as plasticizers.

US 2,585,448 describes mixtures of esters formed from diethylene glycol, triethylene glycol, tetraethylene glycol with aromatic monocarboxylic acids such as benzoic acid and alkyl-substituted benzoic acids such as toluic acid. These esters are used as plasticizers for PVC.

US 4,656,214 describes mixed diesters of linear α, ω-diols having 2 to 8 carbon atoms with a first carboxylic acid of the formula R ¹ R ² R ³ CO ₂ H and a second carboxylic acid of the formula R ⁴ CO ₂ H, wherein R ¹ and R ^{2 are} alkyl radicals of C 1 to C ⁴ , R ^{3 may be} hydrogen or a C 1 to C 6 alkyl radical and R ^{4 may be} an unsubstituted or mono-, di- or tri-alkyl-substituted phenyl radical. When these substances are used as plasticizers for PVC, an improvement of the dirt-repellent properties is achieved.

CN-A-1199042 describes the preparation of use of long chain alkyl benzoates as plasticizers. The starting material for the preparation of the benzoates a methyl benzoate-rich ester mixture is used, which is obtained as a by-product stream in production plants for the production of dimethyl terephthalate (DMT) in small quantities. This contains over 80% by weight of methyl benzoate (BME) and a small percentage of methyl p-toluate (MpT). The ratio of benzoates to p-toluates is accordingly also found in the products obtained from this by-product stream.

In EP 1000009 benzoic acid esters or toluic acid esters of ethylene glycol, diethylene glycol and triethylene glycol have been described as solids having a melting point above 25 ° C. Polymer compositions to which one of these esters is to be added as an additive must be heated at least to the melting point of the ester for homogeneous mixing before addition. By mixing said Diethylengylcol- and Triethylenglycoldiester in certain proportions, liquid compositions can be obtained, which can be used as a plasticizer.

WO 2004/104079 and US 2006/0223925 describe toluic acid ester based compositions and their use as solvents, plasticizers, extenders and / or diluents and a method of making such ester compositions. The starting material for the preparation of the toluates, a methyl p-toluate-rich product stream is used, which is produced as an intermediate stream in production plants for the production of dimethyl terephthalate (DMT) from p-xylene by the Witten process and is converted in further process steps to DMT. The content of MpT in this stream is given as 68-84%, other constituents being DMT (6-20%), methyl p-formylbenzoate (2-6%), p-toluic acid (1-5%) and methyl benzoate (1-3%). The reaction of this product stream with ethylene glycol, diethylene glycol, and triethylene glycol without further purification yields liquid products which are not further specified in color and composition. The pure toluate esters of diethylene glycol and triethylene glycol are also described herein as high melting solids. The claims also include mono- and diesters of the toluic acid of butanediol and other aliphatic diols, which will not be further described.

JP 2008088292 (2008) describes the use of alkylene glycol dibenzoates or alkylene glycol di (alkyl benzoates) in blends with diaryl terephthalates in cellulose ester resins to improve permanence in cellulose ester films for optical polarizing filters. US 2009/286912 and WO 2009/137775 describe the preparation of alkyl p-toluates from methyl p-toluate and primary branched, linear or cyclic C4 to C20 alcohols and their use as plasticizers for PVC.

DESCRIPTION OF THE INVENTION

In the reaction of aliphatic diols such as 1,3-propanediol, 1,4-butanediol, 1,6-hexanediol or 1,12-dodecanediol with pure methyl p-toluate or MpT-rich intermediate streams from DMT production are only solid Products whose melting points are partly above the glass transition temperature of PVC and thus can not be processed with the common methods for the production of PVC blends or PVC plastisols and are therefore not suitable as plasticizers for PVC.

It has now surprisingly been found that compositions of polyalkylene glycol di-p-toluates and benzoates of the formulas (I) and / or (Ia) are well suited as plasticizers for plastics, in particular for homo- and copolymers of vinyl chloride such as PVC. The running numbers m and p describe the length of the alkylene chain and are m = 2, 3, 4, 5 or 6 or p = 1, 2, 3 or 4. These polyalkylene glycol di-p-toluates and benzoates are mixtures of preferred at least three different diesters differing in the number of repeating units [(CH ₂ ) _m O] _n and [CH ₂ R (CH ₂ ) _p O] _q , respectively, described by the run numbers n and q, respectively, from 2 to 20, and the average molecular weight of the poly (oxyalkylene) segment [(CH ₂ ) _m O] _n or [CH ₂ R (CH ₂ ) _p O] _{q is} at least 132 g / mol. The proportion of diesters of p-toluic acid of Formula (I) or (Ia) (where R = ¹ R = methyl) is preferably above 80, more preferably above 90, in particular above 93 wt .-%, based on the weight of the compounds (I) or (Ia ). Compositions of compounds of formulas (I) or (Ia) can be prepared easily and inexpensively by transesterification of methyl p-toluate (MpT, PT-ester) with the corresponding polyalkylene glycols. In contrast to .alpha.,. Omega.-alkylene-di-p-toluates, the inventive compositions of the formulas (I) or (Ia) have melting points which are significantly below the glass transition temperature of PVC, preferably below 25.degree. C. and more preferably below 0 ° C lie. The compositions of the invention have a low solution temperature, high plasticizer efficiency, and high permanence.

The radical R ² is alkyl, which may be straight-chain or branched. Alkyl is preferably C 1 -C 4 -alkyl, in particular C 1 -C 3 -alkyl and particularly preferably methyl or ethyl. m is preferably an integer of 2-6, n is preferably an integer of 2-20, p is preferably an integer of 1-4, and q is preferably an integer of 2-20.

• • mit einem Anteil an Polyalkylenglycol-di-p-toluaten (R = ¹R = Methyl) größer als 80 Gew.-% und
• • mit einer Laufzahl m ausgewählt aus den Werten 2, 3, 4, 5 oder 6 und
• • enthaltend mindestens drei verschiedende Komponenten der Formel (I), die sich in der Anzahl der Oxyalkylen-Wiederholungseinheiten, beschrieben durch die Laufzahl n, die von 2 bis 20 liegen kann, unterscheiden und
• • mit einer mittlere Molmasse des Poly(oxyalkylen)-Segments [(CH₂)_mO]_n von mindestens 132 g/mol,

oder der Formel (Ia)

• • mit einem Anteil an Polyalkylenglycol-di-p-toluaten (R = ¹R = Me) größer als 80 Gew.-% und
• • mit einer Laufzahl p ausgewählt aus den Werten 1, 2, 3 oder 4
• • enthaltend mindestens drei verschiedende Verbindungen der Formel (Ia), die sich in der Anzahl der Oxyalkylen-Wiederholungseinheiten, beschrieben durch die Laufzahl q, die von 2 bis 20 liegen kann, unterscheiden und
• • mit einer mittlere Molmasse des Poly(oxyalkylen)-Segments [CHR²(CH₂)_pO]_q von mindestens 132 g/mol,

als auch Mischungen aus mindestens zwei Zusammensetzungen von Diestern der Formeln (I) und/oder (Ia), die Herstellung dieser Zusammensetzungen und Mischungen sowie deren Verwendung in Formmassen als Weichmacher und in weiteren beschriebenen Anwendungen.The invention therefore relates to liquid compositions of compounds of the formula (I)

• With a proportion of polyalkylene glycol di-p-toluates (R = ¹ R = methyl) greater than 80 wt .-% and
• • with a running number m selected from the values 2, 3, 4, 5 or 6 and
• Containing at least three different components of the formula (I), which differ in the number of oxyalkylene repeat units described by the run number n, which may be from 2 to 20, and
• Having an average molecular weight of the poly (oxyalkylene) segment [(CH ₂ ) _m O] _n of at least 132 g / mol,

or the formula (Ia)

• With a proportion of polyalkylene glycol di-p-toluates (R = ¹ R = Me) greater than 80 wt .-% and
• • with a running number p selected from the values 1, 2, 3 or 4
• Containing at least three different compounds of the formula (Ia), which differ in the number of oxyalkylene repeat units described by the run number q, which may be from 2 to 20, and
• Having an average molecular weight of the poly (oxyalkylene) segment [CHR ² (CH ₂ ) _p O] _q of at least 132 g / mol,

as well as mixtures of at least two compositions of diesters of the formulas (I) and / or (Ia), the preparation of these compositions and mixtures and their use in molding compositions as plasticizers and in other applications described.

Further advantageous embodiments of the invention are set forth in the claims, which are a part of the description and are expressly incorporated herein.

Dimethyl terephthalate (DMT) is industrially produced by oxidation of p-xylene by the Witten process. After a first oxidation step, a product stream is obtained which is rich in methyl p-toluate (MpT) and is separated from the crude DMT and fed to the further oxidation. According to the invention, this stream, which is also referred to as Rohesterkopfprodukt or pT ester, isolated and used as a raw material, optionally after further purification, for the preparation of polyalkylene glycol di-p-toluates, pT ester can from the DMT process in large quantities (eg 25-35%) without adversely affecting the production process itself.

Depending on the oxidation conditions, the pT-ester contains varying amounts of by-products. Typical by-products are methyl benzoate (BME), terephthalaldehyde methyl ester (TAME) and DMT. Typically, the pT ester contains at least 80, preferably at least 85 and particularly preferably at least 90% by weight of MpT (based on the mass of crude ester product). The total amount of by-products is generally not more than 20, preferably 15 and more preferably 10 wt .-% (based on the mass of crude ester). The content of BME is at most 15, preferably at most 10 and particularly preferably at most 7 wt .-%, based on the mass of Rohesterkopfprodukt. By further cleaning the Rohesterkopfprodukts, such as. As distillation, the content of MpT can be further increased and the content of by-product can be further reduced. The content of MpT can be z. B. be increased to more than 98%. Both crude ester product and further purified crude ester product can be reacted in a transesterification reaction with polyalkylene glycols in the presence of a transesterification catalyst. Preference is given to purified MpT.

As polyalkylene glycols it is possible to use linear or branched aliphatic polyalkylene glycols of the formulas (II) or (IIa) for the transesterification reaction. The running number m describes the length of the alkyl chain and is 2 (poly (ethylene glycol), PEG), 3 (poly (trimethylene glycol)), 4 (poly (tetramethylene glycol), PTMEG), 5 (poly (pentamethylene glycol)) and 6 (poly (hexamethylene ether) glycol). The running number p can be 1, 2, 3 or 4. The polyalkylene glycols used are preferably mixtures of at least three different oligomers, which differ by their running numbers n or q, which are preferably 2-20. The average molecular weight of the polyalkylene glycol mixture is indicated by a numerical value after name, trade name or abbreviation of the polyalkylene glycol, e.g. B. PEG1000 for a polyethylene glycol with average molecular weight of 1000 g / mol. Preferred polyalkylene glycols have average molecular weights of at least 150 g / mol. Preferred polyalkylene glycols are polyethylene glycol (PEG) and polytetramethylene ether glycol (PTMEG).

The radical R ² and the run numbers m, n, p and q have the meaning given in the formulas (I) and (Ia).

PEG is prepared by polymerization of ethylene oxide by alkaline or acid catalysis using water, monoethylene glycol or diethylene glycol as the starting molecule. After reaching the desired molecular weight, the reaction is terminated by acid or base addition. At average molar masses of between 200 and 400 g / mol, polyethylene glycols are present as nonvolatile liquids. The melting at 17 to 22 ° C PEG 600 has a paste-like consistency. Above 3000 g / mol, polyethylene glycols are solid substances. Depending on the particular composition, polyethylene glycols are used for a wide variety of applications, eg. B. in pharmaceutical, technical or medical applications.

PTMEG can be prepared by acid catalysis of tetrahydrofuran. The main applications are in the production of polyurethane elastomers, elastic fibers and copolyester ether elastomers. For use in elastomers Polytetramethylenetherglycole must have a certain minimum chain length. In the production, therefore, the low molecular weight PTMEG's are separated and recycled to the manufacturing process. US 6,355,846 describes z. For example, removal of the low molecular weight fractions by thermal processes such as stripping. The separation of the low molecular weight PTMEGs by membrane filtration is described in US 5,434,315 described. The low molecular mass streams are usually recycled to the polymerization process. It is therefore economically advantageous if these low molecular mass streams can be supplied to another use.

Polyethylene glycol (PEG, HO (C ₂ H ₄ O) _n H) and polytetramethylene ether glycol (PTMEG, HO (C ₄ H ₈ O) _q H) are preferably used; the molar masses are preferably between 150 and 1000 g / mol, particularly preferably between 150 and 500 g / mol and most preferably between 150 and 300 g / mol. Particularly preferred commercial polyalkylene glycols are, for. B. PEG200 or Terathane ^® 250th

The starting materials necessary for the compounds of the formulas (I) and (Ia) according to the invention are generally available commercially, and the reaction reactions are known to the person skilled in the art. Suitable for the invention ester starting mixtures fall z. B. in the industrial production of DMT.

In the reaction of MpT, Rohesterkopfprodukt or further purified Rohesterkopfprodukt with α, ω-diols such as ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,6-hexanediol or 1,12-dodecanediol are α, ω-alkylene -p-toluate, which are in solid form and whose melting points are in part above the glass transition temperature of PVC, which precludes use in soft PVC compositions.

The reaction of MpT or Rohesterkopfprodukt with polyalkylene glycols of formula (II) or (IIa), however, surprisingly provides polyalkylene glycol di-p-toluates of the formula (I) or (Ia) in liquid or low melting form, easily with the common methods of PVC Processing can be processed into dry blends or plastiols. The polyalkylene glycol di-p-toluates of the formula (I) or (Ia) (R = R ¹ = methyl) according to the invention have a low volatility and are not classified as SVOC (semi volatile organic compounds) due to the high boiling points.

Crude head product or purified MpT can be reacted with the corresponding polyalkylene glycols in a transesterification reaction in the presence of suitable transesterification catalysts. The liberated in this reaction methanol is distilled off, whereby the balance of the reaction is shifted to the product side.

Suitable reaction temperatures are in the range of 160 ° C to 260 ° C, preferably from 180 ° C to 260 ° C. The optimum temperatures depend on the polyalkylene glycol used, the ratio of MpT / polyalkylene glycol and the type of catalyst used. In general, the temperature must be increased in the course of the reaction, since the boiling temperature of the reaction mixture by the formation of higher boiling polyalkylene glycol di-p-toluate increases. The reaction can also be carried out under reduced pressure (eg less than 1000 mbar) with high-boiling polyalkylene glycols or under overpressure (eg greater than 1000 mbar) with low-boiling polyalkylene glycols.

Suitable catalysts for the transesterification reaction are all catalysts which can catalyze transesterification reactions such as. As titanium compounds, cobalt compounds, manganese compounds, zinc compounds or mixtures thereof. Preference is given to zinc acetate, zinc stearate or tetrabutyl titanate. The catalyst concentration depends on the type of catalyst and is in the range of 0.001 to 2 wt .-%, preferably in the range of 0.005 to 1 wt .-% based on the amount of MpT used. For handling, it is advantageous to add the catalyst in liquid form to the reaction mixture. This can be z. B. by dissolving the catalyst in the polyalkylene glycol or in methanol. To improve the solubility of the catalysts in the reaction mixture may optionally also crown ethers, cryptands, quaternary ammonium salts, ligands, phase transfer catalysts or other substances such as surfactants, emulsifiers and other amphiphilic substances are added, the reactivity of the catalysts, eg. B. by complex formation, solubilization u. Ä., increase.

The crude products obtained after the transesterification reaction contain stoichiometric amounts of MpT (two equivalents) on the one hand, unreacted MpT, on the other monoester of the diols, which must be separated. It is therefore advantageous to use MpT in a stoichiometric excess in order to ensure a complete conversion of the diols into the corresponding ditoluates and to keep the monoester content as low as possible, preferably less than 1%, particularly preferably less than 0.5%, particularly preferably less than 0.1%.

Excess MpT can be removed by reduced pressure thermal processes such as distillation or thin film, short path or falling film evaporators or by flash / stripping with steam.

The polyalkylene glycol di-p-toluates according to the invention can be purified further by suitable cleaning methods known to those skilled in the art, such as filtration, steam distillation (flash, stripping), treatment with activated carbon, decolorization with ozone or other decolorizing agents.

In summary, this means that the preparation of the polyalkylene glycol di-p-toluates (I) and (Ia) according to the invention also simultaneously comprises the preparation of the other compounds (I) and (Ia), as described above. Instead of the starting product MpT z. B. the Rohesterkopfprodukt as starting material or the corresponding benzoic acid and / or toluic acid (mono) esters can be initially charged in order to obtain the desired further compounds of the formulas (I) and (Ia).

The final products obtained are slightly to moderately colored liquids or low-melting substances with Hazen color numbers smaller than 500 Pt-Co units. The color numbers may preferably be less than 300 or in particular less than 150 or 100 Pt-Co units.

For construction products that are to be used inside buildings such. As well as elastic floor coverings, an EU Construction Products Directive requires that no user of a building may be harmed by emissions from construction products. Due to the lack of concretisation of these requirements by the EU, national interpretations are possible. For Germany, for example, there is a rating scheme of the German Institute for Construction Technology (DIBt) for the testing and approval of construction products, which was developed by the Committee for the Health Assessment of Construction Products (AgBB). In this evaluation scheme, emissions are distinguished by VOC (volatile organic compounds) and SVOC (semi volatile organic compounds). VOCs are substances that have retention times by gas chromatographic analysis in the range of n-alkanes with 6 to 16 carbon, SVOCs have retention times above n-hexadecane up to and including n-docosan (nC ₂₂ H ₄₆ ) on. Only if the relevant limit values are complied with will the construction product receive an approval. Emissions above the SVOC grid are not recorded. It is expected in construction product specialist circles that the interpretation of the AgBB for a European regulation will be adopted. It is therefore advantageous if substances intended for use in construction products for the interior have higher retention times than those of n-docosane.

The polyalkylene glycol di-p-toluates (I) or (Ia) according to the invention (R = R ¹ = methyl) have a low volatility and are not classified as SVB according to AgBB because of the high boiling points.

The polyalkylene glycol di-p-toluates according to the invention have low dissolution temperatures for PVC, which are below those of the universal softener DEHP, DINP and DOTP. The low dissolution temperatures indicate a high solvation power and thus a high compatibility of the polyalkylene glycol di-p-toluates with PVC.

The polyalkylene glycol di-p-toluates of this invention are good plasticizers for PVC and are as efficient as DEHP. They have a higher efficiency than DINP, DINCH or DOTP, which is reflected in lower values for Shore A hardness, modulus of elasticity and flexural modulus.

For the applications in electrical cables and in the automotive interior area, special demands are placed on the permanence of the plasticizers. In the automotive interior, the lack of permanence leads to the undesirable phenomenon of fogging. Softener losses on cables result in a change in mechanical properties, which is manifested in a reduction in flexibility and an increase in susceptibility to breakage, which can ultimately lead to the loss of integrity of the cable. For safety reasons, cables are subject to numerous approval tests. PVC compositions containing polyalkylene glycol di-p-toluates according to the invention show, after aging tests, lower mass losses as well as lower mechanical properties than compositions with comparative commercial plasticizers.

Owing to the low volatility and the strong interaction with PVC, which manifests itself in a low dissolution temperature, the polyalkylene glycol di-p-toluates according to the invention and compositions / mixtures (I) or (Ia) containing them have a high compatibility in PVC compounds Permanence on. The polyalkylene glycol di-p-toluates according to the invention are very suitable as plasticizers for PVC, in particular for use in electric cables and in the automotive interior.

The polyalkylene glycol di-p-toluates and mixtures (I) or (Ia) containing them can be used as plasticizers in compositions containing at least one polymer, preferably selected from polyvinyl chloride (PVC), polyvinylidene chloride, polyvinyl bromide (PVB), homo- or Copolymers based on olefins such as ethene, propene, butene, butadiene, cyclic olefins, vinyl acetate derivatives, acrylate derivatives, methacrylate derivatives, stryol derivatives, acrylonitrile derivatives, can be used. Particularly preferred are homopolymers or copolymers of vinyl chloride. They can also be used in paints, varnishes, adhesives, adhesive components and sealants. As a PVC component can be any type such. As suspension, bulk, microsuspension or emulsion PVC or mixtures thereof.

The polyalkylene glycol di-p-toluates according to the invention can be used alone or together with other plasticizers in polymers. The concentration of the polyalkylene glycol di-p-toluates in the polymer composition may be from 1 to 90% by weight, preferably from 15 to 60% by weight, based on the weight of the polymer composition or polymer.

The composition may contain one or more stabilizers such as metal soaps, organic phosphates, epoxy compounds, tin stabilizers and / or mixtures thereof.

In addition, the composition may contain other additives such. As antistatic agents, anti-fog additives, biocides, fillers, UV stabilizers, antioxidants, light stabilizers, optical brighteners, flame retardants, pigments, propellants, kickers and / or mixtures thereof.

The polyalkylene glycol di-p-toluates according to the invention can be used as plasticizers for the production of plastic articles, for example PVC products which are flexible at low temperatures and for the production of self-adhesive films, films for the automotive, furniture and office furniture industries, Agricultural uses, food films, roofing membranes, liners of water tanks and swimming pools, protective films, rainwear, shower curtains, dinghies and water wings are suitable.

The polyalkylene glycol di-p-toluates according to the invention can be used as plasticizers for the production of plastic articles, for example PVC products which are stable at high temperatures, for. As cables for installations, computers or cables in the automotive sector.

The polyalkylene glycol di-p-toluates according to the invention can be used as plasticizers for the production of flexible coatings, such as. As artificial leather, truck tarpaulins and tents, vinyl wallpaper, conveyor belts, protective clothing and underbody protection of motor vehicles, can be used.

The polyalkylene glycol di-p-toluates according to the invention can be used as plasticizers for the production of flexible floors, for. As foamed PVC floors, compact PVC floors and the backs of carpets are used.

The polyalkylene glycol di-p-toluates according to the invention can be used as plasticizers for the production of flexible articles, such. As hoses, seals or other shaped articles such as shoes, toys, gloves and molds are used.

The articles can by various methods such. As calendering, extrusion, coating, casting, dip coating, rotational molding or injection molding.

In addition, the polyalkylene glycol di-p-toluates of the invention can be used as a non-plasticizer component in many products, such. As paints, coatings, paints, adhesives, adhesive products, gaskets, kittens, surfactants, detergents, emulsifiers and lubricants. All the uses mentioned in the preceding sections for the polyalkylene di-p-toluates according to the invention also apply to the compositions according to the invention or mixtures of the formulas (I) and / or (Ia) which contain more than 80% by weight of these toluates , and are also the subject of this invention.

The following examples serve to illustrate the invention without limiting the scope of application that results from the description and the claims.

The features mentioned in the individual examples are basically according to the invention and not limited to the combination with the further features (parameters mentioned in the examples).

measurement methods

• 1. Color Measurements: The color of the raw products and final products will match ISO 6271-1 certainly. The standard describes a visual method for determining the color of clear liquids in Pt-Co units.
• 2. Analysis of the product composition: The identification and determination of the quantitative composition of the components contained in the raw and end products is carried out by means of GCMS or GC (Thermo Electron Corporation, Finnigan Focus GC-DSQ or Focus GC models).

Examples

All information, eg. As%, wt .-%, etc., are in wt .-%.

example 1

Purification of crude ester

Purified MpT is obtained from crude head product from a manufacturer of DMT by the Witten method by bench scale one stage distillation at atmospheric pressure and about 200 to 217 ° C containing about 86 wt% MpT and about 14 wt% BME and has no staining (20 Pt Co units vs. 150 Pt Co units for crude sterol product). This material is obtained by collecting two separate fractions during the distillation. All other impurities remain in the distillation residue.

Pure MpT (99%) from a commercial source is also used (CAS 99-75-2, Alfa Aesar).

Examples of α, ω-alkylene glycol di-p-toluates

example 1

Synthesis of 1,2-ethylene glycol di-p-toluate (p-methylbenzoic acid 2- (p-methylbenzoyl) oxyethyl ester

Purified MpT from Example 1 (50 g, 0.33 mol), 1,2-ethylene glycol (10.3 g, 0.17 mol) and zinc acetate dihydrate (26 mg, 0.12 mmol) are placed in the 100 ml flask slowly heated with column and distillation bridge under nitrogen until the beginning of boiling. The liberated during the reaction methanol is distilled off continuously and the temperature further increased in the further course to 260 ° C until the equivalent amount of methanol is distilled off (after about 3 hours). After cooling, a yellow solid is obtained which contains 60.6% 1,2-ethylene glycol di-p-toluate, 18.9% 1,2-ethylene glycol monobenzoate mono-p-toluate, 1.3% 1, 2-ethylene glycol dibenzoate, 5.5% 1,2-ethylene glycol mono-p-toluate, 0.6% 1,2-ethylene glycol monobenzoate and 9.6% MpT. After recrystallization from methanol, a white solid is obtained which contains 84.8% 1,2-ethylene glycol di-p-toluate, 14.7% 1,2-ethylene glycol monobenzoate mono-p-toluate, 0.25% 1 , 2-ethylene glycol dibenzoate and 0.15% MpT.

Example 2

Synthesis of 1,2-ethylene glycol di-p-toluate (p-methylbenzoic acid 2- (p-methylbenzoyl) oxyethyl ester

Pure MpT from Example 1 (50 g, 0.33 mol, Alfa Aesar), 1,2-ethylene glycol (6.8 g, 0.11 mol) and tetrabutyl titanate (58 mg, 0.17 mmol) are dissolved in 100 ml Slowly heated the flask with the column and the distillation bridge under nitrogen until it begins to boil. The liberated during the reaction of methanol is distilled off continuously and the temperature further increased in the further course to 260 ° C until the equivalent amount of methanol is distilled off (after about 6 hours). After cooling, a dark brown liquid containing 54% MpT, 35.8% 1,2-ethylene glycol di-p-toluate and 9.4% diethylene glycol di-p-toluate is obtained. By fractional distillation in vacuo more volatile components such as excess MpT and by-products are separated (1-1.5 mbar, 50-180 ° C). The end product is distilled at 1.1 mbar and a column head temperature of 180-230 ° C. After cooling, a white solid is obtained containing 86.5% 1,2-ethylene glycol di-p-toluate, 8.0% diethylene glycol di-p-toluate and 2.9% MpT.

Example 3

Synthesis of 1,3-propylene glycol di-p-toluate (p-methylbenzoic acid 3- (p-methylbenzoyl) oxypropyl ester

Purified MpT from Example 1 (70 g, 0.47 mol), 1,3-propanediol (17.7 g, 0.23 mol) and zinc acetate dihydrate (36 mg, 0.17 mmol) are placed in the 250 ml flask slowly heated with column and distillation bridge under nitrogen until the beginning of boiling. The liberated during the reaction methanol is distilled off continuously and the temperature further increased in the further course to 260 ° C until the equivalent amount of methanol is distilled off (after about 4 hours). After cooling, a clear light yellow, oily liquid is obtained containing 67.8% of 1,3-propylene glycol di-p-toluate, 11.5% of 1,3-propylene glycol monobenzoate-p- monotoluate, 0.5% 1,3-propylene glycol dibenzoate, 8.7% 1,3-propylene glycol mono-p-toluate and 10.1% MpT. After recrystallization from methanol, a white solid is obtained which contains 81.8% 1,3-propylene glycol di-p-toluate, 10.9% 1,3-propylene glycol monobenzoate mono-p-toluate, 2.9% 1 , 3-propylene glycol mono-p-toluate and 4.4% MpT.

Example 4

Synthesis of 1,3-propylene glycol di-p-toluate (p-methylbenzoic acid 3- (p-methylbenzoyl) oxypropyl ester

Pure MpT from Example 1 (50 g, 0.33 mol, Alfa Aesar), 1,3-propanediol (8.4 g, 0.11 mol) and tetrabutyl titanate (58 mg, 0.17 mmol) are dissolved in 100 ml Slowly heated the flask with the column and the distillation bridge under nitrogen until it begins to boil. The liberated during the reaction of methanol is distilled off continuously and the temperature further increased in the further course to 260 ° C until the equivalent amount of methanol is distilled off (after about 6 hours). After cooling, a brown liquid is obtained which contains 20.6% of 1,3-propylene glycol di-p-toluate, 12% of di (propylene-1,3-glycol) -di-p-toluate, 3.2% of tri (propylene-1,3-glycol) -di-p-toluate and 63.7% MpT contains. By fractional distillation in vacuo more volatile components such as excess MpT and by-products are separated (0.5-0.7 mbar, 50-200 ° C). The final product is distilled at ~ 0.5 mbar and a column top temperature of 200-230 ° C. After cooling, a white solid is obtained which consists of 1,3-propylene glycol di-p-toluate (> 99%).

Example 5

Synthesis of 1,4-butylene glycol di-p-toluate (p-methylbenzoic acid 4- (p-methylbenzoyl) oxybutyl ester

Pure MpT from Example 1 (50 g, 0.33 mol, Alfa Aesar), 1,4-butanediol (9.9 g, 0.11 mol) and zinc acetate dihydrate (38 mg, 0.17 mmol) are in 100 ml of flask with column and distillation column are slowly heated under nitrogen to boiling point. The liberated during the reaction of methanol is distilled off continuously and the temperature further increased in the further course to 225 ° C until the equivalent amount of methanol is distilled off (after about 2 hours). After cooling, a brown liquid is obtained which contains 11.7% of 1,4-butylene glycol di-p-toluate and 88.2% of MpT. By fractional distillation in vacuo, volatile components such as excess MpT and by-products are separated (1-1.5 mbar, 50-180 ° C). The end product is distilled at 1.1 mbar and a column head temperature of 180-230 ° C. After cooling, a slightly yellowish solid is obtained which consists of 1,4-butylene glycol di-p-toluate (> 99%).

Example 6

Synthesis of 1,6-hexylene glycol di-p-toluate (p-methylbenzoic acid 6- (p-methylbenzoyl) oxyhexyl ester

Pure MpT from Example 1 (50 g, 0.33 mol, Alfa Aesar), 1,6-hexanediol (13 g, 0.11 mol) and zinc acetate dihydrate (38 mg, 0.17 mmol) are dissolved in 100 ml Slowly heated the flask with the column and the distillation bridge under nitrogen until it begins to boil. The liberated during the reaction methanol is distilled off continuously and the temperature further increased in the further course to 225 ° C until the equivalent amount of methanol is distilled off (after about 2.5 hours). After cooling, a pale pale yellow colored solid containing 30% of 1,6-hexylene glycol di-p-toluate and 70% MpT is obtained. After recrystallization with hot methanol and cooling, a white, crystalline precipitate is obtained, which is filtered off, washed with cold methanol and dried. The white solid is 1,6-hexylene glycol di-p-toluate (> 99%).

Example 7

Synthesis of 1,12-dodecylene glycol di-p-toluate (p-methylbenzoic acid 12- (p-methylbenzoyl) oxydodecyl ester

Purified MpT from Example 1 (52 g, 0.35 mol), 1,12-dodecanediol (33.6 g, 0.17 mol) and zinc acetate dihydrate (27 mg, 0.12 mmol) are placed in the 250 ml flask slowly heated with column and distillation bridge under nitrogen until the beginning of boiling. The liberated during the reaction methanol is distilled off continuously and the temperature further increased in the further course to 260 ° C until the equivalent amount of methanol is distilled off (after about 4 hours). After cooling, a yellowish solid is obtained which contains 72.4% 1,12-dodecylene glycol di-p-toluate, 11.9% 1,12-dodecylene glycol monobenzoate mono-p-toluate, 0.4% 1, 12-dodecylene glycol dibenzoate, 7.2% 1,12-dodecylene glycol mono-p-toluate, 0.5% 1,12- Dodecylene glycol monobenzoate and 6.7% MpT contains. After recrystallization from iso-propanol, a white solid is obtained which contains 93.2% 1,12-dodecylene glycol di-p-toluate and 6.8% 1,12-dodecylene glycol monobenzoate mono-p-toluate.

Examples of polyalkylene glycol di-p-toluates according to the invention

Example 8

Synthesis of poly (tetramethylene ether glycol) di-p-toluate (4-methylbenzoic acid ω- (p-methylbenzoyl) poly (oxybutyl) ester

Purified MpT from Example 1 (570 g, 3.8 mol), polytetramethylene ether glycol (PTMEG) INVISTA (Terathane ^® 250) (302 g, 1.3 mol) and zinc acetate dihydrate (283 mg, 1.3 mmol) are slowly heated in a 2000 ml flask with column and distillation bridge under nitrogen until the beginning of boiling. The liberated during the reaction methanol is distilled off continuously and the temperature further increased in the further course to 260 ° C until the equivalent amount of methanol is distilled off (after about 4 hours). After cooling, a yellowish colored liquid is obtained which consists of a mixture of polydisperse 4-methylbenzoic acid ω- (p-methylbenzoyl) poly (oxybutyl) esters, polydispersed 4-methylbenzoic acid ω-methylbenzoylpoly (oxybutyl) esters and polydisperse benzoic acid ω -methylbenzoylpoly (oxybutyl) esters and excess MpT. The polytetramethylene ether glycol used is completely unset according to GC-MS analysis. The excess MpT is removed in vacuo (0.11-1 mbar) at a column top temperature of 50-70 ° C. After cooling, a clear, slightly yellowish liquid is obtained which comprises polydispersed 4-methylbenzoic acid ω- (p-methylbenzoyl) poly (oxybutyl) esters, polydisperse 4-methylbenzoic acid ω-methylbenzoylpoly (oxybutyl) esters and polydisperse benzoic acid ω-methylbenzoylpoly ( oxybutyl) ester.

Example 9

Synthesis of poly (ethylene glycol) -di-p-toluate (4-methylbenzoic acid ω- (p-methylbenzoyl) poly (oxyethyl) ester

Pure MpT from Example 1 (30 g, 0.2 mol, Alfa Aesar), polyethylene glycol (13.2 g, 0.07 mol, PEG200, Acros Organics) and zinc acetate dihydrate (22 mg, 0.1 mmol) in 100 ml flask with column and distillation bridge under nitrogen slowly heated until the beginning of boiling. The liberated in the reaction of methanol is distilled off continuously and the temperature further increased in the further course to 260 ° C until the equivalent amount of methanol is distilled off (after about 2 hours). After cooling, a liquid is obtained which consists of a mixture of polydisperse 4-methylbenzoic acid ω- (p-methylbenzoyl) poly (oxyethyl) esters, polydispersed 4-methylbenzoic acid poly (4-oxyethyl) esters and excess MpT. The polyethylene glycol used is completely converted according to GC-MS analysis. After removal of excess MpT in vacuo (0.3-0.5 mbar) at a column top temperature of 35-62 ° C a liquid is obtained which still contains about 6% MpT.

Example 10

Synthesis of poly (ethylene glycol di-p-toluate (4-methylbenzoic acid ω- (p-methylbenzoyl) poly (oxyethyl) ester

Pure MpT from Example 1 (30 g, 0.2 mol, Alfa Aesar), polyethylene glycol (13.2 g, 0.07 mol, PEG200, Acros Organics) and manganese acetate tetrahydrate (25 mg, 0.1 mmol) in 100 ml flask with column and distillation bridge under nitrogen slowly heated until the beginning of boiling. The liberated in the reaction of methanol is distilled off continuously and the temperature further increased in the further course to 260 ° C until the equivalent amount of methanol is distilled off (after about 2 hours). After cooling, a liquid is obtained which consists of a mixture of polydisperse 4-methylbenzoic acid ω- (p-methylbenzoyl) poly (oxyethyl) esters, polydispersed 4-methylbenzoic acid poly (4-oxyethyl) esters and excess MpT. The polyethylene glycol used is completely seeded according to GC-MS analysis. After removal of excess MpT in vacuo (0.2-0.4 mbar) at a column head temperature of 40-70 ° C, a liquid is obtained which still contains about 6% MpT.

Example 11

Synthesis of polyethylene glycol di-p-toluate (4-methylbenzoic acid ω- (p-methylbenzoyl) poly (oxyethyl) ester

Pure MpT from Example 1 (30 g, 0.2 mol, Alfa Aesar), polyethylene glycol (13.2 g, 0.07 mol, PEG200, Acros Organics) and tetraethyl titanate (35 mg, 0.1 mmol) are dissolved in the 100 ml Flask with column and distillation bridge under nitrogen slowly agitated until the beginning of boiling. The liberated in the reaction of methanol is distilled off continuously and the temperature further increased in the further course to 260 ° C until the equivalent amount of methanol is distilled off (after about 2 hours). After cooling, a liquid is obtained which consists of a mixture of polydisperse 4-methylbenzoic acid ω- (p-methylbenzoyl) poly (oxyethyl) esters, polydispersed 4-methylbenzoic acid poly (4-oxyethyl) esters and excess MpT. The polyethylene glycol used is completely seeded according to GC-MS analysis. After removal of excess MpT in vacuo (0.2-0.3 mbar) at a column top temperature of 35-60 ° C, a liquid is obtained which still contains about 1.5% MpT.

Example 12

Synthesis of polyethylene glycol di-p-toluate (4-methylbenzoic acid ω- (p-methylbenzoyl) poly (oxyethyl) ester

Pure MpT from Example 1 (30 g, 0.2 mol, Alfa Aesar), polyethylene glycol (13.2 g, 0.07 mol, PEG200, Acros Organics) and zinc stearate (65 mg, 0.1 mmol) are in the 100 ml of flask with column and distillation bridge under nitrogen slowly heated until incipient boiling. The liberated in the reaction of methanol is distilled off continuously and the temperature further increased in the further course to 260 ° C until the equivalent amount of methanol is distilled off (after about 2 hours). After cooling, a liquid is obtained which consists of a mixture of polydisperse 4-methylbenzoic acid ω- (p-methylbenzoyl) poly (oxyethyl) esters, polydispersed 4-methylbenzoic acid poly (4-oxyethyl) esters and excess MpT. The polyethylene glycol used is completely seeded according to GC-MS analysis. After removal of excess MpT in vacuo (0.2-0.3 mbar) at a column head temperature of 35-60 ° C, a liquid is obtained which still contains about 10.5% MpT.

Example 13

Synthesis of poly (tetramethylene glycol di-p-toluate (4-methylbenzoic acid ω- (p-methylbenzoyl) poly (oxybutyl) ester

Pure MpT from Example 1 (30 g, 0.2 mol, Alfa Aesar), polytetramethylene ether glycol (PTMEG) INVISTA (Terathane ^® 250) (15.9 g, 0.07 mol) and zinc acetate dihydrate (22 mg, 0.1 mmol) are heated slowly in a 100 ml flask with column and distillation bridge under nitrogen until the beginning of boiling. The liberated during the reaction methanol is distilled off continuously and the temperature further increased in the further course to 260 ° C until the equivalent amount of methanol is distilled off (after about 3 hours). After cooling, a clear, yellowish liquid is obtained which consists of a mixture of polydisperse 4-methylbenzoic acid ω- (p-methylbenzoyl) poly (oxybutyl) esters, polydispersed 4-methylbenzoic acid poly (4-oxybutyl) esters and excess MpT , The used Polytetramethylenetherglycol is completely set according to GC-MS analysis.

Example 14

Melting points of α, ω-alkylene glycol di-p-toluates and polyalkylene glycol di-p-toluates

Melting points are determined by DSC (TA Model DSC Q1000). For this purpose, the samples are cooled in hermetic crucibles to -50 ° C and heated to 450 ° C at 10 K / min. The melting points given in Tab. 1 are the peak maxima of the phase transition. Table 1: Melting points of α, ω-alkylene glycol di-p-toluates and polyalkylene glycol di-p-toluates Melting point [° C] example 1 112 Example 2 117 Example 3 84 Example 4 81.5 Example 5 107.6 Example 6 XX Example 7 50 Example 8 <-45

The results show that the polyalkylene glycol di-p-toluates according to the invention in contrast to the α, ω-alkylene glycol di-p-toluates have significantly lower melting points and are liquid at room temperature, which is advantageous for use as a plasticizer.

Example 15

Determination of the dissolution temperature of polyvinyl chloride (PVC) in plasticizers

To determine the gelling properties of a potential plasticizer, the critical solution temperature of PVC is based on DIN 53 408 certainly. For this purpose, 2.5-5 g of PVC (Vinnolit E70 TT) are suspended in 19 times the amount of plasticizer at room temperature and the temperature is slowly increased (1 K / min). The critical solution temperature is defined as the temperature at which the suspension becomes clear. For comparison, the dissolution temperatures of known plasticizers are determined. The results are summarized in Table 2. Table 2: Dissolving temperature for PVC based on DIN 53408 softener Dissolution temperature [° C] DEHP (di (2-ethylhexyl) phthalate, CAS: 117-81-7) 138 DINP (Diisononyl phthalate, CAS: 68515-48-0) 138 BBP (butyl benzyl phthalate, CAS: 85-68-7) 119 DPGB (dipropylene glycol dibenzoate 80%; CAS: 27138-31-4) 129 Example 8 116

The results show that the polyalkylene glycol di-p-toluates according to the invention have lower dissolution temperatures than the known universal softeners.

Example 16

Volatility of plasticizers at 105 ° C

The volatility of plasticizers is corresponding ASTM D 2288-97 (reapproved 2001) determined at 105 ° C. For this purpose, the pure plasticizers are removed at 105 ° C in a ventilated oven and determines the mass losses after 2, 4 and 24 h. The mass losses of the polyalkylene glycol di-p-toluates according to the invention are shown in Table 3 in comparison with commercially available plasticizers. Table 3: Mass losses of plasticizers according to ASTM D2288-97 at 105 ° C softener Mass losses in [%] after 2 h 4 h 24 hours Di (2-ethylhexyl) phthalate (DEHP, CAS: 117-81-7) 0.2 0.8 5.4 DINCH (Diisononylcyclohexane-1,2-dicarboxylate, CAS: 166412-78-8) 0.1 0.4 2.2 Example 8 0.2 -0.2 -0.4

After 24 h aging at 105 ° C, the plasticizers DINCH and DEHP mass losses of 2.2% and 5.4%, respectively. In contrast, the mass changes in the range of accuracy and thus no detectable mass losses are observed in Example 8 of the invention.

Example 17

Mechanical properties of injection molded PVC plasticizer compositions

PVC dry blends having the compositions shown in Table 4 are made with an industrial Herschel high speed mixer. PVC, stearic acid, stabilizer, and calcium stearate are sheared at a rate of 30 revolutions per minute until a temperature of 82.2 ° C is reached. The rate is then reduced to 18 rpm and the plasticizer added along with the epoxidized linseed oil. The mixture is further sheared until a temperature of 107.7 ° C is reached. After cooling with the water-cooled outer jacket to 71.8 ° C, the mixture is removed and further cooled to room temperature. The PVC dry blends are conditioned for 48 hours before further use.

The commercially available plasticizers DEHP (di-2-ethylhexyl phthalate, CAS: 117-81-7), DINP (diisononyl phthalate, CAS: 68515-48-0), DINCH (diisononylcyclohexane-1,2-dicarboxylate, CAS: 166412-78 8) and DOTP (dioctyl terephthalate, CAS: 6422-86-2) are used as reference softeners. Table 4: Dry blend compositions (all data in phr (= parts per 100 parts PVC)) D1 D2 D3 D4 D5 PVC (Shintech SE 13300F) 100 100 100 100 100 Stabilizer (Akcros LT2001M) 8th 8th 8th 8th 8th Linseed oil (Chemtura Drapex 10.4 ELO) 8th 8th 8th 8th 8th Calcium stearate (Fisher) 1 1 1 1 1 Stearic acid 95% (Aldrich) 5 5 5 5 5 DEHP 50 DINP 50 DINCH 50 DOTP 50 Example 8 50

ASTM test specimen for tensile ( ASTM D 638 Type 1 , Overall length 165 mm, width of the narrow section 13 mm, thickness 3.2 mm, length of the narrow section 57 mm, total width 19 mm, length of the measuring point 50 mm, distance between the supports 115 mm, rounding radius 76 mm) and bending tests ( ASTM D790 , Length 130 mm, width 13 mm, thickness 3.2 mm) are produced by injection molding with the fully electric injection molding machine Roboshot s2000i-B-55. The injection molding parameters are given in Table 5. The specimens are conditioned for 48 hours at 22.8 ° C and 50% relative humidity prior to further use. Table 5: Injection parameters parameter value shot size 5,588 cm injection rate 11.43 cm / s Transfer by position 0.6 compression pressure 414 bar compaction time 5 s Extruder rpm 200 backpressure 10 bar relaxation speed 2.54 cm / s cooling time 10 s mold temperature 40.6 ° C

The train tests are after ASTM D638-03 on an Instron Tensile Tester (Model 4400 R) at a strain rate of 50.8 mm / min and a load of 90.7 kg (200 lbs). Of each composition, five tensile specimens ( ASTM D 638 Type 1 ) and the results are averaged to minimize variations. The results of the tensile test are summarized in Table 6.

Shore A hardness measurements will be appropriate ASTM D2240-05 carried out. The measurements are carried out on bending test specimens ( ASTM D 790 ) carried out. From each composition, the hardness is determined on five samples at five different positions. The results obtained are averaged to minimize variations. The Shore A hardness values are listed in Table 6. Table 6: Mechanical properties of injection molded specimens D1 D2 D3 D4 D5 Young's modulus of elasticity [MPa] 4.6 8.3 8.9 6.5 4.7 Elongation at break (standard) [%] 642 627 561 521 644 Breaking stress [MPa] 12.8 11.32 11.09 11.14 14.3 Maximum load [N] 518 493 560 520 575 Expansion at break [mm] 322 313 280 261 322 Shore A hardness 80 84 85 83 79

To determine the bending modulus, bending tests are carried out with a Tinius Olsen stiffness tester ASTM D747-02 carried out. A load of 151.5 g (0.5 lb) is used. The values for the apparent flexural moduli are listed in Table 7. Table 6: Apparent bending modules at different deflection angles

The polyalkylene glycol di-p-toluates according to the invention have advantageous mechanical properties in PVC compositions. Thus, the plasticizer efficiency for Inventive Example 8 is higher than that of DINP, DINCH and DOTP, which is reflected in lower values for Young's modulus, Shore A hardness and flexural modulus in the single point bend test. Example 8 is similar in elastic modulus and Shore A hardness to DEHP, but has significantly lower volatility and, moreover, has a higher fracture resistance indicated by the higher values of ultimate stress and maximum load.

Tensile specimens prepared from dry blends D1 to D5 are stored in a ventilated oven for 48 h at 80 ° C. The aged samples are subjected to tensile tests as described above and the mechanical properties are determined. In addition, the mass loss after aging is determined.

Table 7 summarizes the data. Table 7: Mechanical properties and mass loss after aging Examples D1 D2 D3 D4 D5 Young's modulus of elasticity without aging [MPa] 4.6 8.3 8.9 6.5 4.7 Young's Young's modulus [MPa] after 48 h 4.1 22.6 10.6 6.41 4.3 Change Young's modulus [%] -11% + 170% + 19% -1% -9% weight loss 2.1 3.2 2.0 1.9 1.4

It can be seen that the high efficiency of the polyalkylene glycol di-p-toluate according to the invention is maintained even on aging, since no increase in the modulus of elasticity is observed. The mass losses of the test specimens determined after aging are smallest in the case of composition D5, which contains Example 8 according to the invention as plasticizer

Example 18

Extraction resistance of PVC plasticizer compositions

The extraction resistance of PVC plasticizer compositions will be appropriate ASTM D 1239-07 carried out. Instead of film samples bending test specimens ( ASTM D 790 ) used. The samples are aged for 24 h at 29.4 ° C and 40.6 ° C in cottonseed oil. The mass losses by extraction are shown in Table 8. Table 8: Mass losses after aging in cottonseed oil for 24 h aging temperature Mass losses [%] 29.4 ° C 40.6 ° C Example D1 0.87 2.43 Example D5 0.82 1.07

The mass loss by extraction with cottonseed oil at 40.6 ° C in the inventive example D5 only about 44% of the mass loss of Example D1 and shows the excellent permanence of the polyalkylene glycol di-p-toluate invention.

The polyalkylene glycol di-p-toluates according to the invention or mixtures / compositions of the formulas (I) or (Ia) containing them have very good softening properties for PVC and are particularly suitable for applications because of their high efficiency, high compatibility, high permanence and aging resistance in electrical cables as well as in the automotive interior. The low dissolution temperature for PVC allows energy-efficient processing at low temperatures. In addition, the polyalkylene glycol di-p-toluates according to the invention can be prepared simply and from inexpensive raw materials.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• US 2585448 [0008]
• US 4656214 [0009]
• CN 1199042A [0010]
• EP 1000009 [0011]
• WO 2004/104079 [0012]
• US 200610223925 [0012]
• JP 2008088292 [0013]
• US 2009/286912 [0013]
• WO 2009/137775 [0013]
• US 6355846 [0024]
• US 5434315 [0024]

Cited non-patent literature

• DIN 53408 [0004]
• ISO 6271-1 [0055]
• DIN 53 408 [0074]
• ASTM D 2288-97 (reapproved 2001) [0076]
• ASTM D 638 Type 1 [0080]
• ASTM D790 [0080]
• ASTM D638-03 [0081]
• ASTM D 638 Type 1 [0081]
• ASTM D2240-05 [0082]
• ASTM D 790 [0082]
• ASTM D747-02 [0083]
• ASTM D 1239-07 [0088]
• ASTM D 790 [0088]

Claims (18)

Composition consisting of compounds of the formula (I)

wherein R and R ^{1 are} independently hydrogen or methyl, m is a number from 2 to 6 and n is a number from 2 to 20, and wherein a) compounds of formula (I) with R = R ¹ = methyl to at least 80 wt b) the composition contains at least 3 different compounds of the formula (I) which differ by the number n, and c) the average mass of the [(CH ₂ ) _m O] _n segment is at least 132 g / mol is. A composition according to claim 1, characterized in that the content of compounds of formula (I) with R = R ¹ = hydrogen, R = hydrogen and R ¹ = methyl or R = methyl and R ¹ = hydrogen is at most 20 wt .-% , A composition according to claim 1 or 2, characterized in that m = 2 and the weight-average running number n over all [(CH ₂ ) _m O] _n- segments is at least 3. Composition according to claim 1 or 2, characterized in that m = 4 and the weight-average running number n over all [(CH ₂ ) _m O] _n- segments is at least 1.8. Composition according to any one of Claims 1 to 4, characterized in that it contains at least 2 compounds of formula (I) differing by the number n. Composition consisting of compounds of the formula (Ia)

wherein R and R ^{1 are} independently hydrogen or methyl and R ^{2 is} alkyl, p is 1, 2, 3 or 4 and q is a number from 2 to 20, and wherein a) compounds of formula (Ia) where R = R ¹ = B) the composition contains at least 3 different compounds of the formula (Ia) which differ by the running number q, and c) the average mass of the [CHR ² (CH ₂ ) _p O] is at least 80% by weight _q segment is at least 132 g / mol. A composition according to claim 6, characterized in that the content of compounds of formula (Ia) with R = R ¹ = hydrogen, R = hydrogen and R ¹ = methyl or R = methyl and R ¹ = hydrogen is at most 20 wt .-% , A composition according to claim 6 or 7, characterized in that p = 1, R ^{2 is} methyl and the weight-average running number q over all [CHR ² (CH ₂ ) _p O] _q segments is at least 2.2. Composition according to any one of Claims 6 to 8, characterized in that they contain at least 2 compounds of formula (Ia) differing by the number q. A process for the preparation of a composition according to any one of claims 1 to 5 comprising the step of reacting an ester mixture containing at least 80% by weight of p-toluic acid C ₁ -C ₄ -alkyl ester with a compound of formula (II)

wherein m and n have the meanings given for the formula (I) and the average molecular weight of the compound (II) is at least 150 g / mol. Process according to Claim 10, characterized in that the compound of the formula (II) used is polyethylene glycol or polytetramethylene ether glycol. A process for the preparation of a composition according to any one of claims 6 to 9 comprising the step of reacting an ester mixture which comprises at least 80% by weight of p-toluic acid C ₁ -C ₄ -alkyl ester with a compound of the formula (IIa)

wherein R ² , p and q have the meanings given for the formula (Ia) and the average molecular weight of the compound (IIa) is at least 150 g / mol. Method according to one of claims 10 to 12, characterized in that is used as the p-toluic acid C ₁ -C ₄ alkyl ester methyl p-toluate. Use of a composition according to any one of claims 1 to 9 as a plasticizer for plastics. Use according to claim 14 as a plasticizer for homopolymers and copolymers of vinyl chloride. Use of a composition according to any one of claims 1 to 9 in paints, lacquers, adhesives, adhesive articles, sealants or putties. Use according to any one of claims 14 to 16, characterized in that the materials containing the composition are used in the automotive industry or for electric cables. Plastic molding compositions containing a composition according to any one of claims 1 to 9.