WO2011110350A1

WO2011110350A1 - Use of 2-propylheptyl esters as plasticizers or viscosity modifiers for polymers

Info

Publication number: WO2011110350A1
Application number: PCT/EP2011/001188
Authority: WO
Inventors: Peter Daute; Martin Schäfer; Heinz Müller
Original assignee: Emery Oleochemicals Gmbh
Priority date: 2010-03-10
Filing date: 2011-03-10
Publication date: 2011-09-15
Also published as: DE102010010985A1; DE102010010985B4

Abstract

The present invention relates to a composition comprising as components (α1) at least one polymer, (α2) 1 to 30 wt.% of a carboxylic acid 2-propylheptyl ester, (α3) 20 to 120 wt.% of at least one plasticizer which differs from components (α1) and (α2), (α4) 0 to 40 wt.% of at least one additive which differs from components (α1), (α2) and (α3), wherein the wt.% data are in each case based on the polymer, and a process for the preparation of a composition, a process for the production of a shaped article, the shaped article obtainable by this process and the use of a fatty acid 2-propylheptyl ester.

Description

USE OF 2-PROPYLHEPTYL ESTERS AS PLASTICIZERS OR VISCOSITY MODIFIERS FOR

POLYMERS

The present invention relates to a composition, a process for the preparation of a composition, a process for the production of a shaped article, the shaped article obtainable by this process and the use of a fatty acid 2-propylheptyl ester.

Plasticizers are substances which are admixed to brittle and hard plastics, such as, for example, polyvinyl chloride (PVC), to impart to these properties which are desirable for processing and use, such as plasticity, flexibility and extensibility. The industrially relevant plasticizers and their use are known and are described, for example, in David F. Cadogan, Christopher J. Howick: "Plasticizers", Ullmann's Encyclopedia of Industrial Chemistry, electronic release, 6th ed., chap. 1 - 6, Wiley- VCH, Weinheim 2003 and L. Meier: "Weichmacher" , in R. Gachter, H. Miiller (ed.): Taschenbuch der Kunststoffadditive, 3rd edition, p. 341 et seq., Hanser, Munich 1990.

Plasticizers are contained in so-called "plastisols" in particularly large amounts. Plastisol moulding compositions are widely used in vehicle construction for stopping, bonding and sealing seams and flanged edges of vehicle body panels internally and externally. In particular, plastisols based on PVC polymers and/or copolymers can be used for this purpose. Such plastisol moulding compositions comprise fine polymer particles which are dispersed in a liquid, non-volatile plasticizer. At room temperature the solid polymer particles are insoluble in the plasticizer, which solvates them, however, at elevated temperature (= gelling), so that a homogeneous solution of the polymer in the plasticizer is obtained, which solidifies on cooling to give a more or less rigid film. Phthalic acid esters, in particular di-2-ethylhexyl phthalate (DEHP), diisononyl phthalate (DINP) or diisodecyl phthalate (DIDP) are conventionally employed as plasticizers in such plastisols. On the basis of discussions on toxic effects on reproduction, which in some cases have already led to stricter labelling under hazardous substances legislation and in the case of infants' toys have also led to restrictions in use, it must be assumed that the use of these phthalates will decrease significantly in the future, especially in sensitive applications, such as foodstuffs packaging and medical uses. Efforts are being made at least to reduce the amount of phthalate-based plasticizers in plastisols. In this connection, EP-A-1 256 566 or also DE-A-10 2008 002 168 Al propose using plasticizers based on citric acid esters instead of those based on phthalates. In these uses, polymeric plasticizers from dicarboxylic acids and diols, which are often more highly viscous than monomelic plasticizers, are also increasingly being employed.

The disadvantage of the plastisols known from the prior art, however, is inter alia that the viscosity of the non-conditioned plastisols, in particular the viscosity of the non- conditioned PVC-based plastisols with a PVC content of at least 50 wt.%, based on the total weight of the plastisol, is very high, so that these plastisols are scarcely suitable for processes in which during the production of shaped articles the plastisols must be poured or sprayed on to substrates or poured or injected into moulds.

The present invention was based on the object of overcoming the disadvantages arising from the prior art in connection with plastisols comprising plasticizers.

In particular, the present invention was based on the object of providing compositions comprising a polymer and at least one plasticizer which are characterized by a low viscosity compared with the compositions known from the prior art. This composition should also comprise the smallest possible amounts of plasticizer with a potential of being toxic to reproduction. The cured shaped articles obtained by gelling this composition should be inferior in none of their properties, for example in their softness, to comparable shaped articles of the prior art. The present invention was furthermore based on the object of providing a process for the preparation of such a composition.

A contribution towards achieving the abovementioned objects is made by a composition comprising as components

(a 1 ) a preferably thermoplastic polymer,

(a2) 1 to 30 wt.%, preferably 3 to 20 wt.% and particularly preferably 2 to 15 wt.% of a carboxylic acid 2-propylheptyl ester, having preferably 5 to 21 and in particular preferably 8 to 18 carbon atoms, furthermore preferably a fatty acid 2- propylheptyl ester having the abovementioned numbers of carbon atoms

(a3) 20 to 120 wt.%, preferably 25 to 100 wt.% and particularly preferably 35 to

80 wt.% of at least one plasticizer which differs from components (al) and (al),

(a4) 0 to 40 wt.%, preferably 1 to 30 wt.% and particularly preferably 1.5 to 25 wt.% of at least one additive which differs from components (al), (a2) and (a3),

wherein the wt.% amounts in each case are based on the polymer.

The composition according to the invention comprises a polymer as component (al).

Possible polymers are, in particular, polymers chosen from the group consisting of polyvinyl chloride (PVC), polyvinylidene chloride (PVDC), polyacrylates, in particular polymethyl methacrylate (PMMA), polyalkyl methacrylate (PAMA), fluoropolymers, in particular polyvinylidene fluoride (PVDF), polytetrafluoroethylene (PTFE), polyvinyl acetate (PVAc), polyvinyl alcohol (PVA), polyvinyl acetals, in particular polyvinyl butyral (PVB), polystyrene polymers, in particular polystyrene (PS), expandable polystyrene (EPS), acrylonitrile/styrene/acrylate (ASA), styrene/acrylonitrile (SAN), acrylonitrile/butadiene/styrene (ABS), styrene/maleic anhydride copolymer (SMA), styrene/methacrylic acid copolymer, polyolefins, in particular polyethylene (PE) or polypropylene (PP), thermoplastic polyolefins (TPO), polyethylene/vinyl acetate (EVA), polycarbonates, polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polyoxymethylene (POM), polyamide (PA), polyethylene glycol (PEG), polyurethane (PU), thermoplastic polyurethane (TPU), polysulphides (PSu), biopolymers, in particular polylactic acid (PLA), polyhydroxybutyric acid (PHB), polyhydroxyvaleric acid (PHV), polyester, starch, cellulose and cellulose derivatives, in particular nitrocellulose (NC), ethylcellulose (EC), cellulose acetate (CA), cellulose acetate/butyrate (CAB), rubber or silicones and mixtures or copolymers of the abovementioned polymers. The composition according to the invention preferably comprises PVC as the polymer of component (al).

Preferably, the composition according to the invention contains the polymer of component (al) in particulate form, if PVC is used in particular the use of suspension, bulk, microsuspension or emulsion PVC being particularly preferred. According to a particular embodiment of the composition according to the invention, the polymer is made up of particles with a particle size of less than 1,000 um, particularly preferably less than 500 μιη, moreover preferably less than 250 μηι and still more preferably less than 100 μηι to the extent of at least 50 wt.%, particularly preferably to the extent of at least 75 wt.% and most preferably to the extent of at least 95 wt.%. Examples of suitable PVC polymers which may be mentioned are, for example, the PVC types obtained under the name VESTOLIT^® from Vestolit GmbH & Co. KG, Marl, Germany, or those obtained under the name PEVIKON^® from Norsk Hydro, Hamburg, Germany.

The composition according to the invention comprises as component (a2) a fatty acid 2- propylheptyl ester, this preferably having the general structure (I)

(I)

in which R is a saturated or unsaturated, linear or branched alkyl radical having 5 to 21 carbon atoms, preferably having 6 to 17 carbon atoms and most preferably having 8 to 14 carbon atoms. Mixtures of various fatty acid 2-propylheptyl esters which differ in the fatty acid component are also conceivable as component (a2).

Such an ester is obtainable, for example, by the reaction of 2-propylhepanol with suitable fatty acids, preferred fatty acids being, in particular, fatty acids chosen from the group consisting of caproic acid, oenanthic acid, caprylic acid, pelargonic acid, capric acid, lauric acid, myristic acid, fish oil fatty acid, palmitic acid, pelagonic acid, margaric acid, stearic acid, isostearic acid, arachic acid, behenic acid, lignoceric acid, cerotic acid, undecylenic acid, oleic acid, elaidic acid, vaccenic acid, icosenic acid, rapeseed oil fatty acid, cetoleic acid, erucic acid, nervonic acid, linoleic acid, linolenic acid, arachidonic acid, timnodonic acid, clupanodonic acid, cervonic acid or a mixture of two or more of these. Carboxylic acid mixtures such as result from naturally occurring oils and fats by the mixing ratios and constituents thereof can likewise be employed.

The preparation of the carboxylic acid or fatty acid 2-propylheptyl ester by the esterification of one of the abovementioned fatty acids or of a derivative thereof (for example an acid chloride, acid anhydride or alkyl ester of these fatty acids) with 2- propylheptanol can be carried out by esterification reactions known to the person skilled in the art. Preferably, the reaction of the alcohol with the acid or the acid derivative is carried out in the presence of an esterification catalyst. Catalysts which can be employed are in principle acids, such as, for example, sulphuric acid, methanesulphonic acid or p- toluenesulphonic acid, other mineral acids or metals or compounds thereof. For example tin, titanium, zirconium, which can be used as finely divided metals or expediently in the form of their salts, oxides or in the form of soluble organic compounds, are suitable. Nevertheless, in contrast to the proton acids, the metal catalysts are high temperature catalysts which often achieve their full activity only at temperatures above 180 °C. The catalyst concentration can be varied within wide ranges, depending on the nature of the catalyst. For proton acids, concentrations of from 0.05 to 2 % by weight, preferably from 0.1 to 1 % by weight, particularly preferably from 0.15 to 0.5 % by weight are conventional. Higher concentrations of acid indeed increase the rate of reaction, but may promote side reactions. Preferably, the esterification is carried out in the temperature range of from 120 °C to 200 °C, particularly preferably in a temperature range of from 130 °C to 180 °C.

The composition according to the invention comprises as component (a3) at least one plasticizer which differs from components (al) and (a2), it being possible in principle for all plasticizers which are conventionally employed as plasticizers for plasticizers, particularly preferably as plasticizers in PVC-based plastisols, to be employed as the plasticizer. In this context, reference may be made by way of example to WO96/028505 and the plasticizers disclosed therein. Possible plasticizers here are, preferably, di- or tricarboxylic acid esters, preferably di- or tricarboxylic acid polyesters, for example phthalic acid esters, in particular di-2-ethylhexyl phthalate (DEHP), diisononyl phthalate (DINP) or diisodecyl phthalate (DIDP), and phthalate-free plasticizers based on citric acid, based on adipic acid and/or based on benzoate esters, in particular tributyl acetylcitrate, tri- (2-ethylhexyl) acetylcitrate, trioctyl citrate, tridecyl citrate, tributyl citrate, trihexyl citrate, triethyl citrate, dioctyl adipate, diisodecyl adipate, diisononyl adipate, bis(2-ethylhexyl) adipate, 2,2,4-triethyl-l,3-pentanediyl dibenzoate and derivatives thereof, tri ethylene glycol dibenzoate, diethylene glycol dibenzoate, diethylene glycol monobenzoate or propylene glycol dibenzoate. In the composition according to the invention, in one embodiment it is therefore preferable for the plasticizer to comprise a dicarboxylic acid ester. In this context it is preferable for the dicarboxylic acid ester to be diisononyl phthalate or an adipic acid polyester or a mixture of the two. The composition according to the invention can contain at least one additive which differs from components (al), (a2) and (<x3) as component (a4), additives which can be employed being, in particular, stabilizers, co-stabilizers, fillers, colouring agents, lubricants, blowing agents, kickers, antioxidants or biocides.

Stabilizers improve the PVC stability, i.e. they prevent inter alia splitting off of hydrogen chloride. Above all inorganic and organic salts of the metals calcium, zinc, tin, magnesium, sodium and potassium are employed for this, for example calcium stearate, sodium stearate, potassium stearate, zinc stearate, magnesium stearate, tin stearate and/or mixtures of the metal salts. Co-stabilizers can furthermore also be added to the composition, it being possible for the co-stabilizers to be, for example, fatty acid esters, preferably long-chain fatty acid esters with a chain length of more than 12 carbon atoms. The fatty acid ester preferably comprises a straight-chain fatty acid and an alcohol. The alcohol is preferably a branched alcohol (with the exception of 2-propylheptanol). An example which may be mentioned is octadecyl acid ester, as well as epoxidized soya oil, epoxidized oleic acid methyl ester, epoxidized linoleic acid methyl ester, epoxidized linolenic acid methyl ester, epoxidized linolenic acid isopropyl ester, epoxidized rapeseed fatty acid methyl ester, epoxidized soya fatty acid methyl ester, epoxidized linseed fatty acid methyl ester or a mixture of these.

Inorganic and organic fillers can be employed as fillers, examples which may be mentioned being kaolin, chalk, talc, aluminium hydroxide and/or ground clay. The particle size of these fillers is preferably less than 250 μπι, particularly preferably less than 100 μπι and still more preferably less than 63 μπι. The composition according to the invention can also contain metallic glitter, glitter powder and glitter platelets or mixtures of these substances as further fillers in order thereby, for example, to achieve particular optical effects. The composition according to the invention can furthermore also contain a polymer-based filler, such as, for example, PAMA, PMMA and/or polyethylene. The composition according to the invention can contain as colouring agents pigments in the pure form, as powdered pigments, as aqueous pigment preparations, preferably as an azo-free coloured pigment, effect pigment and/or azo-free lake dyestuff. Examples which may be mentioned are Pigment Yellow 14 (C.I. 21095), Pigment Red 254 (C.I. 56110), Pigment Orange 34 (C.I. 21110), Pigment Red 122 (C.I. 73915), Pigment Green 7 (C.I. 74260), Pigment White 6 (C.I. 77891), Pigment Black 7 (C.I 77266), Pigment Red 101 (C.I. 77491), Pigment Violet 23 (C.I. 51319), Pigment Blue 29 (C.I. 77007), Pigment Yellow 185 (C.I. 56290), Pigment Yellow 1 (C.I. 11680), Pigment Red 48:2 (C.I. 15865:2), Pigment Red 53:1 (C.I. 15585:1), Pigment Orange 34 (C.I. 21115), Pigment Yellow 83 (C.I. 21108) and Pigment Blue 15 (C.I. 74160).

According to a particular embodiment of the composition according to the invention, this is a plastisol which is present in the form of a dispersion in which the polymer is dispersed in the form of particles in a continuous phase of the plasticizer. In this case two and more particles are thus often at least partly embedded in the continuous phase of the plasticizer as in a matrix, and cannot flow as in bulk goods. It is preferable here for the plasticizer to be employed in an amount in a range of from more than 50 to 120 wt.%, preferably in a range of 60 to 110 wt.% and particularly preferably in a range of from 70 to 100 wt.%, in each case based on the polymer.

In a further embodiment of the composition according to the invention, it is preferable for the polymer to be present as bulk goods in the form of particles which can move relative to one another, these particles comprising the plasticizer. In this case the particles are not dispersed in a continuous phase of the plasticizer and can therefore flow freely. This is often achieved in that a liquid plasticizer is taken up by the polymer already present in particle form. The polymer particles often swell here by at least 1.1 times their volume compared with the non-swollen state. Preferably, the polymer particles take up in a range of from 10 to 50 wt.%, preferably in a range of from 15 to 40 wt.% and particularly preferably in a range of from 20 to 30 wt.% of plasticizer, in each case based on the polymer. The average size of the particles (d₅₀) is generally in a range of from 10 to 5 μηι, preferably in a range of from 50 to 200 μιη and particularly preferably in a range of from 60 to 10 μηι. A good flowability of the polymer at high plasticizer contents and therefore a good processability are said to be achieved by the above measures.

Preferably, the composition according to the invention, but in particular the dispersion described above, is characterized in that at a content of polymer, in particular at a content of PVC, of at least 50 wt.%, based on the total weight of the composition, it has a Brookfield viscosity, determined at 40 °C, of less than 10,000 mPas, particularly preferably of less than 5,000 mPas, still more preferably of less than 2,500 mPas and most preferably of less than 2,000 mPas.

A contribution towards achieving the abovementioned objects is also made by a process for the preparation of a composition comprising the process steps:

(β 1 ) provision of a preferably thermoplastic polymer,

(β2) provision of a carboxylic acid 2-propylheptyl ester,

(β3) provision of at least one plasticizer which differs from the components provided in process steps (βΐ) and (β2),

(β4) optionally provision of at least one additive which differs from the components provided in process steps (βΐ), (β2) and (β3),

mixing of the components provided in process steps (βΐ), (β2), (β3) and (β4) to obtain a composition; (β6) in one embodiment optionally and in a further embodiment of the invention necessarily heating of the composition to 160 to 220 °C. The heating is preferably carried out under conditions which lead to gelling of the composition to give a preferably elastic plasticated material.

In process steps (βΐ), (β2), (β3) and (β4), the polymer, the fatty acid 2-propylheptyl ester, the plasticizer which differs from the polymer and the fatty acid 2-propylheptyl ester and optionally the at least one additive which differs from the polymer, the fatty acid 2- propylheptyl ester and the plasticizer are first provided, those compounds or components which have already been mentioned as preferred polymers, fatty acid 2-propylheptyl esters, plasticizers and additives in connection with the composition according to the invention being preferred as the polymer, as the fatty acid 2-propylheptyl ester, as the plasticizer and as the additive.

In process step (β5) of the process according to the invention, the components provided in process steps (βΐ), (β2), (β3) and (β4) are then mixed to obtain a composition, it being possible for details of the preparation of plastisols, in particular with respect to the mixing devices used for this, to be found, for example, in the following technical books: Krekeler, Wick, Kunststof -Handbuch (1963), volume II, part 1, page 21 et seq.., W.A. Colomb, Verlag Stuttgart; Becker, Braun, Kunststoff-Handbuch (1986), volume II, part 1 and 2, Hanser Verlag, Munich- Vienna. Preferably, the components are mixed at a temperature in a range of from 10 to 50 °C and/or under an absolute pressure of less than 1,000 mbar, particularly preferably of less than 500 mbar and most preferably of less than 100 mbar. Such a reduced pressure is often applied after mixing has been started or after the end of the mixing. The reduced pressure treatment as a rule lasts until the composition is degassed. Blistering in the shaped article or film produced from the composition can be reduced or even avoided in this way.

According to a particularly preferred embodiment of the process according to the invention, the components provided in process steps (βΐ), (β2), (β3) and (β4) are employed in relative amounts such that the composition according to the invention described above is obtained. In connection with the process according to the invention, it is furthermore preferable for a dispersion in which the polymer is dispersed in the form of particles in a continuous phase of the plasticizer to be obtained in process step (β5).

A contribution towards achieving the abovementioned object is also made by a process for the production of a shaped article, comprising the process steps:

a) the provision of a composition according to the invention or a composition obtainable by the process according to the invention,

b) the conversion of the composition into a defined shape,

c) the heating of the composition,

d) the cooling of the composition to obtain a shaped article.

In process step a), a composition according to the invention or a composition obtainable by the process according to the invention is first provided, this composition preferably being a PVC-based plastisol in which PVC particles are dispersed as component (al) in a continuous phase of the plasticizer (a3).

In process step b), this composition is then shaped. This can be effected by applying the composition to a substrate surface in the form of a coating. In vehicle construction, for example, plastisols, in particular PVC plastisols, are applied in this way either to non- degreased untreated sheet metal in bodyshell construction, or after the electro-dipcoating to metal sheets provided with priming conventionally applied cataphoretically. If the plastisols are applied in bodyshell construction, the gelling operation (process step c) with subsequent solidification takes place in a pre-gelling oven before the electro-dipcoating or in the stoving oven of the electro-dipcoating. In the case of application to electro-dipcoated metal sheets, the solidification of the plastisols takes place during stoving of the subsequently applied filler material, i.e. an intermediate layer of a coating, or finishing lacquers.

The shaping of the composition in process step b) can optionally also be effected by filling the composition into a mould, for example in the context of an injection moulding process. The composition can optionally also be foamed before or during the shaping of the composition according to process step b).

In process step c) the composition is then heated and gelled by this method and manner, the temperature and the duration of the heating depending on the precise composition of the composition. The temperature to which the composition is heated in process step c) is conventionally in a range of from 140 °C to 240 °C, particularly preferably in a range of from 160 °C to 220 °C, while the duration of the heating is in a range of from 60 seconds to 20 minutes, preferably 1 to 10 minutes.

In process step d) the composition is cooled to obtain a cured shaped article. For this, the shaped article is allowed to cool to a temperature in a range of from 15 °C to 60 °C, preferably 20 °C to 40 °C and most preferably to room temperature.

A contribution towards achieving the abovementioned objects is also made by a shaped article obtainable by the process described above.

A contribution towards achieving the abovementioned objects is furthermore made by the use of a fatty acid 2-propylheptyl ester as a viscosity modifier in combination with plasticizers for polymers, particularly preferably as a plasticizer or viscosity modifier in PVC-based plastisols. The invention is now explained in more detail with the aid of non-limiting examples.

EXAMPLES

1. Preparation of PVC pastes

The following PVC pastes PI, P2 and P3 are prepared (amounts stated in g):

PVC rEVUCON^® DP 1000 PVC paste from Norsk Hydro

VESTINOL Diisononyl phthalate from Evonik Degussa

GmbH

REAGENS CL 145 Liquid stabilizer from Reagens Deutschland

GmbH

From the PVC powder and the various additives, pastes PI (not according to the invention), P2 (not according to the invention) and P3 (according to the invention) are prepared in a dissolver from Werner Mathis AG, Oberhasli, Switzerland. The dispersing is carried out at room temperature (approx. 20 °C) and in vacuo (100 mbar). Determination of the viscosity of pastes PI, P2 and P3

The Brookfield viscosity at 40 °C was determined for the pastes PI, P2 and P3 obtained above. The following measurement values were obtained:

By the addition according to the invention of fatty acid 2-propylheptyl esters as plasticizers or viscosity reducing agents, the viscosity of the PVC pastes can be reduced significantly. In particular, due to the use of fatty acid 2-propylheptyl esters the amount of phthalate plasticizer in the PVC paste can be reduced significantly.

Gelling of PVC pastes PI. P2 and P3

The pastes were gelled in a Mathis Thermotester (Werner Mathis AG) to give sheeted-out compounds (180 °C, 3 minutes). The Shore A hardness, which is a measure of the softness of a test specimen, was then determined. The further a standardized needle can penetrate into the test specimen over a certain measurement time, the lower the measurement value. The following measurement values were obtained:

These results show that the addition according to the invention of fatty acid 2- propylheptyl esters as plasticizers or viscosity reducing agents does not adversely influence the properties of the gelled composition.

Claims

1. A composition comprising as components

(al) at least one polymer,

(a.2) 1 to 30 wt.% of a carboxylic acid 2-propylheptyl ester,

(a3) 20 to 120 wt.% of at least one plasticizer which differs from components (al) and (a2),

(a4) 0 to 40 wt.% of at least one additive which differs from components (al), (a2) and (a3), wherein the wt.% amounts in each case are based on the polymer.

2. Composition according to claim 1, wherein the polymer is polyvinyl chloride

(PVC).

3. Process according to claim 1 or 2, wherein the thermoplastic polymer is comprised in particulate form in the composition.

4. Composition according to one of the preceding claims, wherein the fatty acid 2- propylheptyl ester has the general structure (I)

H H H

I I I

H— C— C— C-H

O H H H

R— C— O— C-C-H

H H H H H I I I I I

H-C-C-C-C-C- Ή

I I I I I H H H H H

(I)

in which R is a saturated or unsaturated, linear or branched alkyl radical having 5 to 21 carbon atoms.

5. Composition according to one of the preceding claims, wherein the plasticizer comprises a dicarboxylic acid ester.

6. Composition according to claim 5, wherein the dicarboxylic acid ester is diisononyl phthalate or adipic acid polyester or a mixture of the two.

The composition according to one of the preceding claims, wherein the composition is a dispersion in which the polymer is dispersed in the form of particles in a continuous phase of the plasticizer.

Composition according to one of claims 1 to 6, wherein the polymer is present in the form of particles as bulk goods, wherein these particles comprise the plasticizer.

9. A process for the preparation of a composition, comprising the process steps:

(β 1 ) provision of a polymer,

(β2) provision of a carboxylic acid 2-propylheptyl ester, (β3) provision of at least one plasticizer which differs from the components provided in process steps (βΐ) and (β2),

(β5) mixing of the components provided in process steps (βΐ), (β2), (β3) and (β4) to obtain a composition.

10. Process according to claim 9, wherein the components provided in process steps (βΐ), (β2), (β3) and (β4) are employed in relative amounts such that a composition as defined in one of claims 1 to 8 is obtained.

11. Process according to claim 9 or 10, wherein the polymer is employed in particulate form.

12. Process according to one of claims 9 to 11, wherein the mixing is carried out at a temperature in a range of from 10 to 50 °C.

13. Process according to one of claims 9 to 12, wherein the plasticizer comprises a dicarboxylic acid ester.

14. Composition according to claim 13, wherein the dicarboxylic acid ester is diisononyl phthalate or an adipic acid polyester or a mixture of both.

15. Process according to one of claims 9 to 14, wherein in process step (β5) a dispersion in which the polymer is dispersed in the form of particles in a continuous phase of the plasticizer is obtained.

16. A process for the production of a shaped article, comprising the process steps: a) the provision of a composition as defined in one of claims 1 to 8, or a composition obtainable by a process as defined in one of claims 9 to 15, b) the shaping of the composition, c) the heating of the composition, d) the cooling of the composition to obtain a shaped article.

17. Shaped article obtainable by a process according to claim 16.

18. Use of a fatty acid 2-propylheptyl ester as a viscosity modifier in combination with a plasticizer for polymers.