WO2013026916A1

WO2013026916A1 - 1,2-alkylene-di-p-toluates and -benzoates, method for the production thereof and their use

Info

Publication number: WO2013026916A1
Application number: PCT/EP2012/066483
Authority: WO
Inventors: Maik MALESSA; Stephan KRETSCHMER
Original assignee: Invista Technologies S.À.R.L
Priority date: 2011-08-25
Filing date: 2012-08-24
Publication date: 2013-02-28
Also published as: EP2748246A1; DE102011111624A1

Abstract

Compositions of formula (I), wherein R and R¹ independently represent hydrogen or methyl, R² represents alkyl and R³ represents hydrogen or alkyl, the content of compounds of formula (I) wherein R = R¹ = methyl being 80 to 99 wt.-%, are suitable as plasticizers for plastic materials, especially for homo- and copolymers of vinyl chloride, such as PVC.

Description

1,2-Alkylenedi-p-toluates and benzoates, their preparation and their use

description

The invention relates to 1,2-alkylene-di-p-toluates and benzoates, their preparation from alkyl-p-toluic acid esters or benzoic acid esters and vicinal aliphatic 1, 2-diols, their use as plasticizers and articles, materials and Molding compositions containing at least one compound of the type 1, 2-alkylene-di-p-toluate.

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.

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 ability of the plasticizer, by penetration of the PVC polymer matrix, to reduce the interactions between the polymer chains and thus to produce a softening effect. As a measure of the gelling behavior of a plasticizer, the dissolution temperature for PVC according to DIN 53408 can be determined.

In the past, the chronic toxicity of phthalates has been controversial. As a result of these ongoing discussions to this day 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, especially PVC, which do not have the disadvantages known from the prior art as possible or only to a lesser extent. These new plasticizers should preferably have the phthalates comparable or improved plasticizer properties, have a good gelling behavior or a low dissolution temperature and can be prepared from inexpensive raw materials. Also, they should be as harmless as possible regarding their toxicity.

STATE OF THE ART

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

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 C0 ₂ H and a second carboxylic acid of the formula R ⁴ C0 ₂ H, where R and R ^{2 are} alkyl radicals of C1 to C4, R ^{3 is} hydrogen or a C 1 to C 6 alkyl radical and R ^{4 is} an unsubstituted or mono-, di- or tri-alkyl-substituted phenyl radical could be. When these substances are used as plasticizers for PVC, an improvement of the dirt-repellent properties is achieved.

CN-A-1199042 (1998) describes the preparation and 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. It 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 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 for producing such ester compositions. As a starting material for the preparation of the toluates, a methyl p-toluate-rich product stream is used, which is used as an intermediate stream in production plants for the production of Dimethyl terephthalate (DMT) is produced from p-xylene by the Witten process and converted into DMT in further process steps. 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.

[0012J JP 2008088292 (2008) describes the use of alkylene glycol dibenzoates or alkylene glycol di (alkyl benzoates) in mixtures 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 C 4 -C 20 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 the DMT production Only solid products are obtained whose melting points are in part 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 1, 2-alkylene-p-toluic acid diester (also 1, 2-alkylene-4-methylbenzoic diester, 1,2-alkylene glycol di-p-toluate, 1,2-alkane diol p-toluate or 1,2-alkylene di-p-toluate called) and mixtures thereof with the corresponding monoesters and benzoic acid esters of the formula (I) as a plasticizer for plastics, and in particular for homo- and copolymers of vinyl chloride such as PVC, good are suitable. The proportion of 1,2-alkanediol di-p-toluates of the formula (I) (R = ¹ R = methyl) is preferably above 85 wt .-%, more preferably above 90 wt .-%, in particular above 93% by weight. 1, 2-alkylene-p-toluic acid diester of the formula I can be easily and inexpensively by transesterification of methyl p-toluate (MpT, PT ester) with 1, 2-alkylene glycols (1, 2-alkanediols) produce. In contrast to α, ω-alkylene-di-p-toluates and the ditolates of ethylene glycol, diethylene glycol, which are solid at room temperature, the inventive, 2-alkylene-p-toluic diester of the formula I are surprisingly liquids, the significantly lower melting points ( <-45 ° C).

In the formula (I), R and R ¹ independently of one another are hydrogen or methyl, R ^{2 is} alkyl and R ^{3 is} hydrogen or alkyl. The radicals R ² and R ³ may also form a ring. Alkyl represents straight-chain or branched alkyl and is preferably C1-C4-alkyl, in particular C1-C3-alkyl, and particularly preferably methyl and ethyl.

The invention therefore compositions comprising or consisting of compounds of formula (I), with a proportion of 1,2-alkylene glycol di-p-toluate (s) (I) (R = ¹ R = methyl) of preferably 80 to 99 wt .-% (based on the compounds (I)), the preparation of compounds of formula (I) and corresponding compositions (I) with a proportion of 1, 2-alkanediol di-p-toluates of greater as 80 wt .-% and molding compositions of the invention and Article containing the toluates (I) or the compositions (I). Furthermore, the invention comprises the use of 1, 2-alkylenediol di-p-toluates (I) (R = R = methyl) and the compositions (I) as plasticizers for plastics, in particular for homo- and copolymers of vinyl chloride, such as PVC. The number of different compounds (I) in said compositions (I) is arbitrary, but is at least 2 (or more) different compounds (I).

The invention likewise relates to the use of 1,2-alkylene glycol di-p-toluates (I) (R = R ¹ = ethyl) and of the abovementioned compositions / mixtures (I) comprising or consisting of the compounds (I) in all the applications mentioned below.

Further advantageous embodiments of the invention are given in the claims, which are both part of the description and incorporated herein by reference.

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 esters, isolated and used as a raw material for the preparation of 1, 2-alkylene-di-p-toluates. pT ester can be removed from the DMT process in large quantities (e.g., 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 most preferably at least 90% by weight of MpT (based on the mass of crude head product). The total amount of by-products is generally not more than 20, preferably 15 and particularly preferably 10% by weight (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 purification of the crude ester product, such as distillation, the content of pT can be further increased and the content of by-product can be further reduced. The content of MpT can be increased to more than 98%, for example. Both crude ester product and further purified crude ester product can be reacted in a transesterification reaction with 1,2-diols in the presence of a transesterification catalyst. Preferably Rohesterkopfprodukt is used.

As, 2-diols, linear, branched or cyclic aliphatic, 2-diols of the formula (II) can be used for the transesterification reaction. These can be used as a single component or in mixtures of two or more of these diols.

The radicals R ² and R ³ have the meaning given for formula (I).

The 1,2-diols may e.g. from terminal alkenes, e.g. by reaction to 1, 2-alkylene oxides and subsequent hydrolysis of the oxirane ring. The reaction can be carried out with or without isolation of the 1, 2-alkylene oxides. For example, can be reacted according to EP 1025072 1-alkenes with hydrogen peroxide and formic acid to form a mixture of the vicinal diols and formic acid esters of vicinal diols, wherein one or both of the hydroxyl groups can be esterified. To get to the vicinal diols, the formic acid esters must be cleaved.

2-methyl-1,2-propanediol (isobutylene glycol) can be prepared, for example, from isobutene by epoxidation and subsequent opening of the oxirane ring. Isobutene itself is produced in oil processing in the C4 section or can be prepared by cleavage of MTBE (methyl tert-butyl ether). An alternative approach by catalytic reduction of methyl hydroxyisobutyrate is described in US 6194618. Methyl hydroxyisobutyrate itself is industrially made from acetone and methanol and is further converted to methyl methacrylate (MMA) by dehydration.

1, 2-propanediol (PropyJengJycol) is industrially produced by hydrolysis of propylene oxide, which in turn can win from propene. 1,2-Propanediol can also be made from renewable resources, e.g. from glycerol, which is produced in large quantities in the production of biodiesel.

Examples of 1,2-diols which are preferred according to the invention are 1, 2-propanediol, 2-butanediol, 1, 2-pentanediol, 1, 2-hexanediol, 1, 2-octanediol, 2-methyl-1, 2 Propanediol (isobutylene glycol), 2-methyl, 2-butanediol, 3-methyl-1, 2-butanediol, cyclohexane-1, 2-diol. Preference is given to those 1,2-diols which are available inexpensively and in large quantities. Particularly preferred are 1, 2-propanediol and

1.2-butanediol. The starting materials necessary for the diesters according to the invention are generally available commercially, the reaction reactions known in the art. Ester starting mixtures suitable for the invention fall e.g. 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, 12-dodecanediol are α, ω- alkylene-p-toluate obtained, which are in solid form and whose melting points are in part above the glass transition temperature of PVC, which excludes use in soft PVC compositions.

The reaction of MpT or Rohesterkopfprodukt with, 2-diols, however, surprisingly provides 1, 2-alkylene-di-p-toluate of the formula I in liquid form, which easily with the common methods of PVC processing to dry blends or plastiols can be processed. The 1, 2-alkylene-di-p-toluates of the formula I (R ¹ = R = methyl) have a low volatility and are not classified as SVOC (semi volatile organic compounds) due to the high boiling points.

Rohesterkopfprodukt or purified MpT can be reacted with the corresponding 1,2-diols 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 270 ° C, preferably from 180 ° C to 260 ° C. The optimum temperatures depend on the 1, 2-diol used, the ratio of MpT / 1, 2-diol and the type of catalyst used. In general, the temperature must be increased in the course of the reaction, since the boiling point of the reaction mixture by the formation of higher-boiling 1, 2-alkylene-di-p-toluate increases. The reaction can also be carried out under reduced pressure (eg less than 1000 mbar) with high-boiling 1, 2-diols or under excess pressure (eg greater than 1000 mbar) with low-boiling 1,2-diols. Suitable catalysts for the transesterification reaction are all catalysts which can catalyze transesterification reactions such as titanium compounds, cobalt compounds, manganese compounds, zinc compounds or mixtures thereof. Preference is given to zinc acetate, zinc stearate or tetrabutyl titanate. A logistical advantage results for cobalt acetate, for the case that the preparation of the inventive 1, 2-alkylene-di-p-toluate is integrated into a production network with a DMT production plant. 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 done for example by dissolving the catalyst in the 1, 2-diol 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, which increase the reactivity of the catalysts, eg by complexation, solubilization, among others.

The use of Rohesterkopfprodukt has an advantageous effect on the reaction. The reaction is faster and more stable and the liberated methanol is easier to remove from the reaction mixture. The crude products obtained after the transesterification reaction contain stoichiometric amounts of MpT (two equivalents) on the one hand unreacted MpT, on the other hand monoesters of the diols, which must be separated. It is therefore advantageous to use MpT in stoichiometric excess in order to ensure a complete conversion of the diols into the corresponding ditoluates and to keep the content of monoester as low as possible, preferably less than 1%, particularly preferably less than 0.5% by weight. ,

After removal of excess MpT by means of thermal processes under reduced pressure such as distilling off or thin film, short-path or falling film evaporator, a moderately to strongly colored, product is obtained both when using pure MpT and Rohesterkopfprodukt, which may be additionally clouded , Excess MpT can also be removed by steam distillation (eg flash / stripping). By thermal separation methods such as rectification, thin-film, short-path or falling film evaporation, the inventive 1, 2-alkylene di-p-toluate can further purify, with clear, colorless to pale yellowish colored products are obtained. Hazen color numbers are at most 100 Pt-Co units, preferably at a maximum of 50 Pt-Co units. In addition, catalyst residues are removed in this step. The thermal purification is carried out in two steps, in a first is at reduced pressure (0.1 to 100 mbar) excess starting material removed. For the distillation of the 1, 2-alkylene-di-p-toluate invention, the temperature can then be further increased. The negative pressure can be kept at the same level, optionally can be further reduced. Optionally, any hydrolysis products formed, such as p-toluic acid, can be neutralized prior to thermal purification.

The thermal purification can be preferably used in the inventive 1, 2-alkylene-di-p-toluates whose boiling points are below 400 ° C, preferably below 390 ° C. Particular preference is given to purifying the di-p-toluates of 1,2-propylene glycol and 1,2-butylene glycol according to the invention by thermal processes. For inventive 1, 2-alkylene-di-p-toluate with higher boiling points, a thermal purification is associated with a very high cost, which does not appear justified economically in the currently available technical knowledge. Optionally, in this case, after removal of excess starting materials, the products obtained can be further purified by other suitable cleaning methods known to those skilled in the art, such as filtration, steam distillation, flash / stripping, activated charcoal, ozone deinking or other decolorizing agents, the final products being of a stronger color than those which can be thermally purified on products. Optionally, the inventive 1, 2-alkylene-di-p-toluates with lower boiling points can be further purified by other methods such as washing, filtration, steam distillation, treatment with activated carbon or decolorizing with ozone or other Entfärbemitteln.

When using Rohesterkopfprodukt as starting material and the secondary components react in a transesterification reaction with the 1, 2-diols. The products formed with DMT and TA E remain in the thermal purification in the sump, since their boiling points significantly above those of 1, 2-alkylene-di-p- Toluates lie. The presence of BME leads to the statistical formation of very small amounts of 1, 2-alkylene-dibenzoaten and small amounts of mixed benzoate-p-toluate ester of 1, 2-diol, wherein the amount of the mixed diester with the amount of BME in the raw ester used correlates , The content of 1,2-alkylene dibenzoates is preferably less than 1, particularly preferably less than 0.5% by weight, that of 1,2-alkylene benzoate p-toluates is preferably less than 10, more preferably less than 7% by weight. -%, in each case based on the total amount of the compounds of formula (I). In summary, this means that the preparation of the 1,2-alkylalkylene-di-p-toluate according to the invention as a sub-group of the formula (I) simultaneously also comprises the preparation of the other compounds (I) as described above. Instead of the starting product MpT, for example, the so-called crude ester head product is used as the starting material, or the corresponding benzoic acid and / or toluic acid (mono) esters can also be initially charged in order to obtain the desired further compounds (I).

The final products obtained are lightly colored to colorless with Hazen color numbers smaller than 100 Pt-Co units, preferably smaller than 50 Pt-Co units. The melting points of the inventive, purified 1, 2-alkylene-di-p-toluate are below 0 ° C, preferably below -25 ° C, more preferably below -45 ° C.

For building products to be used inside buildings, such as resilient 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 to 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 n-docosan (n-C22H46). 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 1,2-alkylene-di-p-toluates (I) (R = R ¹ = methyl) have low volatility due to their high boiling points and are not classified by the retention times as SVOC to AgBB, which also for 1, 2-propylene-di-p-toluate as the simplest representative of the inventive 1, 2-alkylene-di-p-toluate applies.

The structurally related 1, 2-Propylenglycoldibenzoat (PGB2) is much more volatile and is right on the border between SVOC and non-classification. In order to achieve a similar low volatility with 1, 2-propylene-di-p-toluate, a correspondingly longer diol component must be used in dibenzoates, which connects the two Benzoateinheiten together. For example, dipropylene glycol (DPG) is used, as in dipropylene glycol dibenzoate (DPGB2), which is commercially available eg as an 80% blend with other dibenzoates. The reduced volatility of the DPGB2 compared to the PGB2 is, however, paid for by the two disadvantages of a higher price of DPG and the lower solvation power of the DPGB2 associated with the ether bond. The lower solvation power can be derived theoretically by comparison of the solubility parameter components, on the other hand, this is also reflected in the determination of the dissolving temperature of PVC in plasticizers according to DIN 53408, which is significantly higher for DBGB2 than for the Compounds according to the invention 1, 2-propylene-di-p-toluate and 1, 2-butylene-di-p-toluate.

The dissolution temperatures of PVC in 1, 2-propylene-di-p-toluate and 1, 2- ßutylen-di-p-toluate are even below those of DBP and DIBP, and in addition do not have the problem of high volatility classified as SVOC short-chain phthalates.

Due to the low volatility and the strong interaction with PVC, which manifests itself in a low dissolution temperature, the inventive 1, 2-alkylene-di-p-toluate, preferably 1, 2-propylene-di-p-toluate and 1, 2-butylene-di-p-toluate, very suitable as a plasticizer for PVC and other plastics and have a high compatibility and permanence. The 2-alkylene-di-p-toluates (I) according to the invention (also called 1,2-alkylene glycol di-p-toluates) can be used as plasticizers in compositions comprising at least one polymer, preferably selected from polyvinyl chloride (PVC) , Polyvlnylidenchlorid, 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, are 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. Suspension, bulk, microsuspension or emulsion PVC or mixtures thereof.

The 2-alkylene-di-p-toluates according to the invention can be used alone or together with other plasticizers in polymers. The concentration of the 1,2-alkylene-di-p-toluate 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. 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 e.g. Anti-static agents, anti-fog additives, biocides, fillers, UV stabilizers, antioxidants, light stabilizers, optical brighteners, flame retardants, pigments, propellants, kickers and / or mixtures thereof.

The 1, 2-alkylene-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 automobile -, furniture, office furniture industry, agricultural applications, food films, roofing membranes, liners of water tanks and swimming pools, protective films, rainwear, shower curtains, dinghies and water wings are suitable. The 1,2-alkylene-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, such as cables for installations, computers or cables in the automotive sector , The 1, 2-alkylene-di-p-toluates according to the invention can be used as plasticizers for the production of flexible coatings, such as artificial leather, truck tarpaulins and tents, vinyl wallpaper, conveyor belts, protective clothing and underbody protection of motor vehicles. The 1,2-alkylene-di-p-toluates according to the invention can be used as plasticizers for the production of flexible floors, for example foamed PVC Floors, compact PVC floors and the backs of carpets are used.

The 1,2-alkylene-di-p-toluates according to the invention can be used as plasticizers for the production of flexible articles, such as e.g. Hoses, gaskets or other shaped articles such as shoes, toys, gloves and molds.

The articles can be prepared by various methods, e.g. Calendering, extrusion, coating, casting, dip coating, rotational molding or injection molding.

In addition, the 1,2-alkylene-di-p-toluates can be used as a non-plasticizer component in many products, e.g. Paints, coatings, lacquers, adhesives, adhesives, gaskets, kites, surfactants, detergents, emulsifiers and lubricants.

All of the uses mentioned in the preceding sections for the 1,2-alkylene-di-p-toluates according to the invention also apply to the compositions / mixtures (I) according to the invention which contain these toluates at 80-99% by weight and are also 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.

Measuring Methods 1. Color measurements: The color of the raw products and end products is determined according to ISO 6271-1. The standard describes a visual method for determining the color of clear liquids in Pt-Co units.

2. Analysis of 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 GC-MS or GC (Thermo Electron Corporation, models Finnigan Focus GC-DSQ or Focus GC).

Examples

All indications, e.g. as%, wt.%, etc. are in weight%. example 1

Purification of crude ester

Crude head product (pT-ester) from a manufacturer of DMT according to the Witten method is used. It contains 89-91% by weight of MpT, 5.5-7% by weight of BME, 0.5-2.3% by weight of DMT, 0.1-1.5% by weight of TAME and traces of other compounds.

Purified MpT is obtained by single-stage distillation of crude ester head product on a laboratory scale at atmospheric pressure and about 200 to 217 ° C containing about 86 wt .-% MpT and about 14 -weight% BME and no staining (20 Pt-Co Units versus 150 Pt Co units for crude head product). This material is obtained by collecting two separate fractions during the distillation. All other impurities remain in the distillation residue.

Pure MpT from a manufacturer of DMT according to the Witten method was used. The content of MpT was greater than 99%. Pure MpT (99%) from a commercial source was also used (CAS 99-75-2, Alfa Aesar). Examples of α, ω-alkylene glycol di-p-toluates Example 2

Synthesis of 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 added in 00 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 260 ° C until the equivalent amount of methanol is distilled off (after about 3 hours). After cooling, a yellow solid is obtained, containing 60.6% of 1, 2-ethylene glycol di-p-toluate, 18.9% of 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%) of 1,2-ethylene glycol di-p-toluate, 14.7% of 1,2-ethylene glycol monobenzoate mono-p-toluate, 0.25%. 1,2-ethylene glycol dibenzoate and 0.15% MpT. Example 3

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, 0.1 mol) and tetrabutyl titanate (58 mg, 0.17 mmol) are in the 100 ml of flask with column and distillation bridge under nitrogen slowly heated until incipient boiling. 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 is obtained containing 35.8% of 1,2-ethylene glycol di-p-toluate, 9.4% of diethylene glycol di-p-toluate and 54% of MpT. By fractional distillation in vacuo are more volatile components such as excess MpT and by-products separated (1-1, 5 mbar, column head temperature: 50-180 ° C). The end product is distilled at 1, 1 mbar and a column top temperature of 180-230 ° C. After cooling, a white solid was obtained containing 86.5% 1,2-ethylene glycol di-p-toluate, 8.0% diethylene glycol di-p-toluate and 2.9% MpT.

Example 4

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 in 250 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 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%, 3-propylene glycol di-p-toluate, 11.5% 1, 3-propylene glycol monobenzoate p-monotoluate, 0.5% 1, 3-propylene glycol dibenzoate, 8.7%, 3-propylene glycol mono-p-toluate and 10.1% MpT. After recrystallization from methanol, a white solid is obtained which contains 81.8% of 1,3-propylene glycol di-p-toluate, 10.9% of 1,3-propylene glycol mono-benzoate mono-p-toluate, 2.9%, 3-propylene glycol mono-p-toluate and 4.4% MpT.

Example 5

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 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 in the course continues to 260 ° C. increased 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 dipropylene-1,3-glycol di-p-toluate, 3.2% of tripropylene

Contains 1.3-glycol di-p-toluate and 63.7% MpT. By fractional distillation in vacuo more volatile components such as excess MpT and by-products are separated (0.5-0.7 mbar, column head temperature: 50-200 ° C). The final product is distilled at -0.5 mbar and a column head temperature of 200-230 ° C. After cooling, a white solid is obtained which consists of 1,3-propylene glycol di-p-toluate (> 99%).

Example 6

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) In the 00 ml flask with column and distillation bridge under nitrogen slowly heated until incipient boiling. 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 more volatile components such as excess MpT and by-products are separated (0.2-1 mbar, column head temperature: 50-70 ° C). The end product is distilled at 0.7 mbar and a column head temperature of 170-215 ° C. After cooling, a slightly yellowish solid is obtained which

1,4-Butylene glycol di-p-toluate (> 99%).

Example 7

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 in 100 ml of flask with column and distillation column are slowly heated under nitrogen to boiling point. 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% of 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 consists of 1,6-hexylene glycol di-p-toluate (> 99%).

Example 8

Synthesis of 1,2-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 in 250 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 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% of 1,2-dodecylene glycol di-p-toluate, 11.9% of 1,1-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. After recrystallization from iso-propanol, a white solid is obtained which contains 93.2% of 1,1,2-dodecylene glycol di-p-toluate and 6.8% of 1,2-dodecylene glycol monobenzoate mono-p-toluate.

Examples of 1,2-alkylene glycol di-p-toluates according to the invention Example 9

Synthesis of, 2-propylene glycol di-p-toluate (p-methylbenzoic acid 2- (p-methylbenzoyl) oxyproplester

Pure MpT from Example 1 (50 g, 0.33 mol, DMT manufacturer), 1, 2-propylene glycol (8.4 g, 0.1 mol) and zinc stearate (108 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 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, pale-colored liquid (40 Pt-Co units) is obtained which contains 43.5% of 1,2-propylene glycol di-p-toluate, 4.4% of 1,2-propylene glycol mono-p toluate and 51, 4% MpT. By fractional distillation in vacuo more volatile components such as excess MpT and by-products are separated (1-10 mbar, column head temperature: 50-140 ° C). After cooling, an orange-brown turbid liquid containing 1, 2-propylene glycol di-p-toluate (> 99%) is obtained. Distillative purification in vacuo at 0.2-1 mbar and a column overhead temperature of 140-170 ° C yields a clear colorless liquid (10 Pt Co units) containing 1,2-propylene glycol di-p-toluate (> 99%). ) contains. Example 10

Synthesis of 1,2-propylene glycol di-p-toluate (p-methylbenzoic acid 2- (p-methylbenzoyl) oxyproplester

Pure MpT from Example 1 (50 g, 0.33 mol, DMT manufacturer), 1, 2-propylene glycol (8.4 g, 0.11 mol) and cobalt acetate tetrahydrate (42 mg, 0.17 mmol) are slowly heated in a 100 ml flask with column and distillation bridge under nitrogen until the beginning of boiling. The experiment is stopped after boiling for 6 hours. No reaction was observed. Example 11

Crude head product from Example 1 (100 g, 0.66 mol, DMT manufacturer), 2-propylene glycol (16.7 g, 0.22 mol) and cobalt acetate tetrahydrate (85 mg, 0.34 mmol) are in 250 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 in the course further increased to 260 ° C until the equivalent amount of methanol is distilled off (after about 5.5 hours). After cooling, a clear, tan-colored liquid is obtained which contains 29.4% of 1,2-propylene glycol di-p-toluate, 10.9% of 1,2-propylene glycol monobenzoate mono-p-toluate, 4.1 % 1, 2-propylene glycol mono-p-toluate, 0.7% 1, 2-propylene glycol monobenzoate, 52.7% MpT and 2, 1% methyl benzoate. The crude product thus obtained is not further purified.

Example 12

Synthesis of 1,2-propylene glycol di-p-toluate (p-methylbenzoic acid 2- (p-methylbenzoyl) oxyproplester). Crude ester product from Example 1 (100 g, 0.66 mol, DMT manufacturer), 1, 2-Propylene glycol (16.7 g, 0.22 mol) and tetrabutyl titanate (116 mg, 0.34 mmol) are slowly heated in a 250 ml flask equipped with a distillation column under nitrogen until the mixture begins to boil distilled off continuously and the temperature is further increased further to 260 ° C. until the equivalent amount of methanol has distilled off (after about 4 hours) .After cooling, a brown liquid is obtained which contains 54.6% of 1,2-propylene glycol. di-p-toluate, 6.5% 1, 2-propylene glycol monobenzoate mono-p-toluate, 0.4%, 2-propylene glycol mono-p-toluate, 34.9% MpT and 1, 6% methyl benzoate The crude product thus obtained is not further purified. Example 13

Crude head product from Example 1 (50 g, 0.33 mol, DMT manufacturer), 1,2-propylene glycol (8.4 g, 0.11 mol) and manganese acetate tetrahydrate (37 mg, 0.17 mmol) in 100 ml flask with column and distillation bridge under nitrogen slowly heated until the beginning of boiling. 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 reddish liquid is obtained which contains 49.7% of 1,2-propylene glycol di-p-toluate, 5.8% of 1,2-propylene glycol monobenzoate mono-p-toluate, 1.8% 1, 2-propylene glycol mono-p-toluate, 40.9% MpT and 1, 4% methyl benzoate contains. The crude product thus obtained is not further purified.

Example 14

Crude head product from Example 1 (100 g, 0.66 mol, DMT manufacturer), 1,2-propylene glycol (16.7 g, 0.22 mol) and zinc acetate dihydrate (75 mg, 0.34 mmol) in 100 ml flask with column and distillation bridge under nitrogen slowly heated until the beginning of boiling. The liberated during the reaction of methanol is distilled off continuously and the temperature in the course further increased to 250 ° C until the equivalent amount of methanol is distilled off (after about 5 hours). After cooling, an orange-reddish liquid is obtained which contains 40.5% 1,2-propylene glycol di-p-toluate, 5.3% 1,2-propylene glycol monobenzoate mono-p-toluate, 3.1%. 1, 2-propylene glycol mono-p-toluate, 0.3% 1, 2-propylene glycol monobenzoate, 48.9% MpT and 1, 9% methyl benzoate. The crude product thus obtained was not further purified. Example 15

Crude head product from Example 1 (500 g, 3.33 mol, DMT manufacturer), 1,2-propylene glycol (83.6 g, 1.10 mol) and zinc acetate dihydrate (374 mg, 1.7 mmol ) are slowly heated in a 1000 ml flask with column and distillation bridge under nitrogen until the beginning of boiling. 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 clear, reddish liquid is obtained which contains 37.1% 1,2-propylene glycol di-p-toluate, 4.7% 1,2-propylene glycol monobenzoate mono-p-toluate, 6.9%. 1, 2-propylene glycol mono-p-toluate and 49% MpT. By fractional distillation in vacuo more volatile components such as excess MpT and by-products are separated (0.9-1, 1 mbar, column head temperature: 55-180 ° C). The final product is distilled at 0.9-2.4 mbar and a column overhead temperature of 180-235 ° C to give a clear pale-colored liquid (<100 Pt-Co units) containing 90.5% 1, 2. Propylene glycol di-p-toluate and 8.5% 1, 2-propylene glycol monobenzoate mono-p-toluate.

Example 16

Crude head product from Example 1 (250 g, 1.67 mol, DMT manufacturer), 1, 2-propylene glycol (41, 8 g, 0.55 mol) and zinc acetate dihydrate (187 mg, 0.85 mmol) In the 500 ml flask with column and distillation bridge under nitrogen slowly heated until incipient boiling. The liberated during the reaction of methanol is distilled off continuously and the temperature in the course further increased to 240 ° C until the equivalent amount of methanol is distilled off (after about 3.5 hours). After cooling, a bright yellow colored liquid is obtained containing 30.6% 1,2-propylene glycol di-p-toluate, 5.4% 1,2-propylene glycol monobenzoate mono-p-toluate, 9.4%. , 2-propylene glycol mono-p-toluate, Contains 50.7% MpT and 2.6% methyl benzoate. By fractional distillation in vacuo more volatile components such as excess MpT and by-products are separated (1, 4-3.4 mbar, column head temperature: 55-180 ° C). The end product is distilled at 1, 3 mbar and a column top temperature of 180-230 ° C. This gives a clear pale colored liquid (40 Pt Co units) containing 84.3% 1,2-propylene glycol di-p-toluate and 14.8% 1,2-propylene glycol monobenzoate mono-p-toluene. contains toluate.

Example 17

Crude head product from Example 1 (250 g, 1.67 mol, DMT manufacturer), 2-propylene glycol (41.8 g, 0.55 mol) and tetrabutyl titanate (290 mg, 0.85 mmol) are dissolved in 500 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 250 ° C until the equivalent amount of methanol is distilled off (after about 4 hours). After cooling, a brown liquid is obtained which contains 56.4% of 1,2-propylene glycol di-p-toluate, 7.9% of 1,2-propylene glycol monobenzoate mono-p-toluate, 32.7% of MpT and Contains 2.0% methyl benzoate. By fractional distillation in vacuo more volatile components such as excess MpT and by-products are separated (3-4 mbar, column head temperature: 55-180 ° C). The end product is distilled at 3 mbar and a column top temperature 180-230 ° C. A clear, slightly colored liquid (50 Pt-Co units) containing 90.2% of 1,2-propylene glycol di-p-toluate, 9.2% of 1,2-propylene glycol monobenzoate mono-p- toluate and 0.6% MpT. Example 18

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

Pure MpT from Example 1 (200 g, 1.33 mol, DMT manufacturer), 1, 2-Butylene glycol (39.6 g, 0.44 mol) and tetrabutyl titanate (232 mg, 0.68 mmol) are in 500 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 260 ° C until the equivalent amount of methanol is distilled off (after about 3 hours). After cooling, an orange-brown liquid containing 66.5% 1,2-butylene glycol di-p-toluate and 32.2% MpT is obtained. By fractional distillation in vacuo more volatile components such as excess MpT and by-products are separated (1, 1-1, 5 mbar, column head temperature: 55-180 ° C). The end product is distilled at 1, 1 mbar and a column top temperature of 180-230 ° C. After cooling, a clear, slightly yellowish liquid is obtained (70 Pt-Co units) consisting of 1,2-butylene glycol di-p-toluate (98.9%).

Example 19

Synthesis of 1,2-Butylene glycol p-ditoluate (p-methylbenzoic acid 2- (p-methylbenzoyl) oxybutyl ester

Rohesterkopfprodukt from Example 1 (250 g, 1.67 mol, DMT manufacturer), 1, 2-Butylene glycol (49.5 g, 0.55 mol) and zinc acetate dihydrate (187 mg, 0.85 mmol) are in the 500th ml of flask with column and distillation bridge under nitrogen slowly heated until incipient boiling. The liberated during the reaction of methanol is distilled off continuously and the temperature further increased in the further course to 230 ° C until the equivalent amount of methanol is distilled off (after about 3 hours). After cooling, a green-yellowish liquid is obtained which contains 24.6% of 1,2-butylene glycol di-p-toluate, 4.4% of 1,2-butylene glycol monobenzoate mono-p-toluate, 10.9% of 1, 2-Butylene glycol mono-p-toluate, 1, 1% 1, 2-Butylene glycol monobenzoate, 52.2% MpT and 2.9% BME. By fractional distillation in vacuo more volatile components such as excess MpT and by-products are separated (1-1, 3 mbar; 180 ° C). The final product is distilled at 0.9-1 mbar and a column overhead temperature of 180-230 ° C. After cooling, a clear, slightly yellowish liquid is obtained (40 Pt-Co units) which consists of 84.4% of 1,2-butylene glycol di-p-toluate and 15.4% of 1,2-butylene glycol monobenzoate. mono-p-toluate.

Example 20

Crude head product from Example 1 (150 g, 1, 0 mol, DMT manufacturer), 1,2-Butyfenglycol (29.7 g, 0.33 mol) and tetrabutyl titanate (174 mg, 0.51 mmol) are in 500 ml flask slowly heated with column and distillation bridge under nitrogen 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 3.5 hours). After cooling, a brown liquid is obtained which contains 38.7% of 1,2-butylene glycol di-p-toluate, 5.9% of 1,2-butylene glycol monobenzoate mono-p-toluate, 52.5% of MpT and 2, Contains 9% BME. By fractional distillation in vacuo more volatile components such as excess MpT and by-products are separated (1-1, 3 mbar, column head temperature: 50-200 ° C). The final product is distilled at 0.9-1 mbar and a column top temperature of 200-230 ° C. After cooling, a clear, yellowish liquid is obtained (300 Pt-Co units) consisting of 89.5% of 1: 1 -butylene glycol di-fi-toluate and 10.5% of 2-butylene glycol monobenzoate mono-p -Toluat exists. Example 21

Synthesis of 1,2-hexylene glycol p-ditoluate (p-methylbenzoic acid 2- (p-methylbenzoyl) oxybutyl ester

Pure MpT from Example 1 (50 g, 0.33 mol, Alfa Aesar), 1, 2-hexanediol (13 g, 0.11 mol) and zinc acetate dihydrate (38 mg, 0.17 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 in the further course to 240 ° C. increased until the equivalent amount of methanol is distilled off (after about 4 hours). After cooling, a clear yellow liquid (250 Pt-Co units) is obtained which contains 23.3% of 1,2-hexylene glycol di-p-toluate, 11.9% of 1,2-hexylene glycol mono-p-toluate and 59.1% MpT. By fractional distillation in vacuo more volatile components such as excess MpT and by-products are separated (0.2-0.4 mbar, column head temperature: 50-2 0 ° C). The end product is distilled at 1.1 mbar and a column top temperature of 210-220 ° C. After cooling, a clear, pale colored liquid is obtained (40 Pt Co units) consisting of 1,2-hexylene glycol di-p-toluate (> 99%).

Example 22

Melting points of, ω-alkylene glycol di-p-toluates and 1, 2-alkylene glycol di-p-toluates

The melting points of the described in Examples 2 to 20 α, ω-alkylene glycol di-p-toluate and 1, 2-alkylene glycol di-p-toluate 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 Table 1 are the peak maxima of the phase transition.

Table 1: Melting points of α, ω-alkylene glycol di-p-toluates

and 1, 2-alkylene glycol di-p-toluates

The results show that the inventive 1, 2-alkylene-di-p-toluates, in contrast to the isomers, ω-alkylene glycol di-p-toluates have significantly lower melting points and are liquid at room temperature, which is for the use is advantageous as a plasticizer.

Example 23

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 determined on the basis of DIN 53 408. 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]

Di (2-ethylhexyl) phthalate (DEHP, CAS: 117-81-7) 138

Diisononyl phthalate (DINP, CAS: 68515-48-0) 138

Butylbenzyl phthalate (BBP, CAS: 85-68-7) 1 19

Dibutyl phthalate (DBP, CAS: 84-74-2) 103

Diisobutyl phthalate (DI BP, CAS: 84-69-5) 102

Dipropylene glycol dibenzoate (80%, DPGB, CAS: 129

dibenzoate 27138-31-4)

Example 14 93

Example 15 90

Example 16 91

Example 17 97

Example 19 95

The results show that the 1,2-alkylene-di-p-toluates or compounds of the formula (I) according to the invention have lower dissolution temperatures than the known plasticizers having the lowest dissolution temperatures.

Claims

claims

1. Composition consisting of compounds of the formula (I)

wherein

R and R ^{1 are} independently hydrogen or methyl, R ^{2 is} alkyl and R ^{3 is} hydrogen or alkyl, wherein the content of compounds of formula (I) with R = R ¹ = methyl is 80 to 99 wt .-%.

2. Composition according to claim 1, characterized in that the content of compounds of the formula} (J) with R = R ¹ = hydrogen, R = hydrogen and R ¹ = methyl and R = methyl and R ¹ = hydrogen 1 to 20 wt .-% is.

3. Composition according to claim 1 or 2, characterized in that the alkyl radicals R ² and R ³ are different from one another.

4. Composition according to one of claims 1 to 2, characterized in that in formula (I) R ^{2 is} alkyl and R ^{3 is} hydrogen.

5. Composition according to one of claims 1 to 4, characterized in that in formula (I) R ^{2 is} methyl.

6. Composition according to one of claims 1 to 5, characterized in that in formula (I) R ^{2 is} ethyl.

7. Composition according to one of claims 1 to 6, characterized in that in formula (I) R ² and R ^{3 are} ethyl.

8. A process for preparing a composition according to any one of claims 1 to 7 comprising the step of reacting an ester mixture containing at least 80 wt .-% p-toluic acid-Ci-C4-alkyl ester, with a compound of formula (II)

wherein R ² and R ^{3 have} the meanings given for the formula (I).

9. The method according to claim 8, characterized in that is used as the p-toluic acid CrC ₄ alkyl ester methyl p-toluate.

10. The method according to claim 8 or 9, characterized in that is used as the ester mixture, the Rohesterkopfprodukt from the Dimethylterephthalatherste / Iung according to the Witten method.

1 1. A method according to any one of claims 8 to 10, characterized in that is used as the compound of the formula (II) 1, 2-butanediol or 1, 2-propanediol.

12. Use of a composition according to any one of claims 1 to 7 as a plasticizer for plastics.

13. Use according to claim 12 as a plasticizer for homopolymers and copolymers of vinyl chloride.

14. Use of a composition according to any one of claims 1 to 7 as a component of paints, lacquers, adhesives, adhesive articles, sealants and - mittein or kitten.

15. Use of a compound of formula (I) according to any one of claims 1 and 3 to 7, wherein in formula (I) R and R ^{1 is} IVIethyl, as a plasticizer for plastics, in particular homo- and copolymers of vinyl chloride, and as a component of Paints, varnishes, adhesives, sealants or kittens.

16. Plastic molding composition comprising a composition according to any one of claims 1 to 7 or a compound according to claim 15.