WO2021133303A1

WO2021133303A1 - A new process for preparing compositions which facilitate grinding and which prevent agglomeration for solid powder lubricants

Info

Publication number: WO2021133303A1
Application number: PCT/TR2020/051111
Authority: WO
Inventors: Sezgi ERDOGAN; Tughan AKBASAK; Semih Durmus; Onur KIPRI
Original assignee: Ak-Kim Kimya Sanayi Ve Ticaret Anonim Sirketi
Priority date: 2019-12-23
Filing date: 2020-11-16
Publication date: 2021-07-01
Also published as: TR201921081A2

Abstract

The present invention relates to a process so as to prepare a fatty acid ester-based internal or external lubricant composition for use in shaping plastics. Said process comprises the following steps; subjecting at least one fatty acid or oil component with at least one alcohol component to esterification reaction under suitable conditions so as to obtain at least one fatty acid ester; adding at least one anti-agglomeration additive to the fatty acid ester obtained as a result of the reaction before grinding; and grinding obtained mixture into powder form.

Description

A NEW PROCESS FOR PREPARING COMPOSITIONS WHICH FACILITATE GRINDING AND WHICH PREVENT AGGLOMERATION FOR SOLID POWDER LUBRICANTS

TECHNICAL FIELD

The present invention relates to a process for preparing new lubricant compositions with improved performance having internal and external lubricant properties so as to be used in the plastic sector, particularly in PVC applications.

KNOWN STATE OF THE ART

PVC also consists of long chain molecules like all polymers. These are highly viscous in melt state and are tend to adhere to the metal components of the process equipment. This problem can be eliminated by using lubricants. The main function of the lubricants in rigid PVC (rPVC) and other polymers is to reduce internal and external friction. Therefore, advantages are provided such as ease of flowing at lower temperatures, decrease in degradation tendency of the polymer, increase in production rate, decrease in equipment wear, and less energy consumption.

The lubricants are generally classified as internal or external. The solubility of the lubricant is generally determined by the molecular structure and polarity of the polymer. Full solubility is not desired depending on the possibility of polymer decomposition between the lubricant and the polymer. Both types of lubricant function differently, although they are mixed with PVC polymer. In addition to this, most lubricants have combinations with both internal and external lubricant properties.

External lubricants are substantially insoluble in PVC. In the melt state, they migrate to the polymer surface and show external lubricant property on the metal surface of the process equipment. In this case, the bonding force between polymer and lubricant is weak. The lubricant substance coats the metal surface of the process equipment and provides external lubricant property by means of reducing the friction on the surface.

Mostly the internal lubricants are soluble in PVC. They act by being involved in the movement of PVC chains at the molecular level during the process and they serve as internal lubricants. The required effect for an internal lubricant is to provide that the polymer chains arrange themselves in the direction of flow. Therefore, the shear stress between the polymer and the molecules is reduced by the internal lubricant, thus melt viscosity and temperature increase reduces.

There are many types of ester lubricants used in various rPVC formulations: Basic esters, glycerol esters, polyglycerol esters, montan esters, partial esters of multifunctional alcohols, fully esterified esters of multifunctional alcohols. Except montan esters, these esters are produced from various alcohols and fatty acids. These lubricants are generally referred to as fatty acid esters. Esters are generally all-purpose and their properties can vary as either internal or external lubricant with increasing carbon chain length and esterification degree. For this reason, the lubricating properties of an ester can be adapted for certain applications.

In the state of the art, there are documents that disclose various lubricant mixtures. In the application US 95,286, a lubricant system for PVC applications is described. In said lubricant system, a lubricant system with multi component comprising ester and/or fatty acid-fatty alcohol ester, and an ester mixture and/or another ester and optionally metal soap is described. Selection of each component carefully and determination of the optimum amounts for each component requires a complex preparation step so as to obtain the required properties with said lubricant system.

Monoesters of high saturated fatty acids are colorless, odorless and are solids with crystalline. These are the internal lubricants of esters that functions most. The most common of these is glycerol monostearate (GMS). The GMS is a mostly and “internal" lubricant with some “external" features. Increasing the degree of esterification increases the external lubricant features.

The most widely used fatty acid as a lubricant for rPVC is the mixture of palmitic (16 carbon chain length) and stearic (18 carbon chain length) acids. In addition to some internal lubricant features, they are also good external lubricants. The biggest disadvantage of them is low volatility.

When processing of rPVC becomes more complex, ratios increase, and parts become more complex, it is more critical to have well-balanced lubricant systems having good internal and external properties. This condition generally requires a mixture of two or more internal and external lubricants. The following can be listed as examples to these; paraffin/oxidized polyethylene/calcium stearate, oxidized polyethylene/fatty acid ester, mixture of fatty acid esters, paraffin/amide, etc. Particularly in the production of PVC films with calendaring process, an adhesion problem of the hot film to mechanical parts and cylinders is experienced. This situation leads to physical deformations on the film and the product is not obtained in the desired quality. Although this situation decreases slightly when the isotridecylstearate product, that is known by the abbreviation G-40 and exhibits internal lubricating properties is used alone, it does not disappear fully and it affects the visual and physical performance of the final product.

Although the internal lubricant properties are sufficient in the system when isotridecylstearate is used, when the processed product is removed from the mold, passes through the screw or over the cooling cylinders particularly for film products, adhesion and thus deformation problems in the final product may be seen, also plate-out problem may be seen. Only the internal lubricant property is insufficient at this point.

During the grinding process of fatty acid esters with solid physical status into powder form in the equipment such as razor grinding mill, gear grinding mill, blade grinding mill, disc grinding mill, shredder to which the material contacts with the metal surface and in which heating occurs due to friction and rotation, they melt and contaminate on metal parts in a hard molten state. In this case, the most important reason for the material to be melted is that the softening temperature of these ester products is at low temperature values between 40- 60°C. Said types of grinding mills are preferred to obtain powder form due to their economic advantage; but, materials that remain in molten form on metal parts pose an important obstacle so as to provide the products in the required form, and make the process difficult and also increase the cost and labor.

Another disadvantage experienced is that these fatty acid ester based lubricant materials produced in powder form are agglomerated and even petrified during the processes such as starting from the packaging storage, transportation, keeping in inventory. Another method used so as to achieve powder form is injection cooler systems.

Even in injection cooler systems, achieving the powder form does not prevent the product from agglomeration and petrifying subsequently. The most important reason for this is the temperature of the product exiting the spray head, in other words the packaging temperature. Formation of agglomeration in powder lubricants packed at 35-45°C over time is inevitable. Heavy cooling systems are required to carry out packing at lower temperatures, and the costs of these systems are quite high. In patent application numbered US 2005/0234171 A1 discloses a process for preparing esters in granular form of certain particle sizes. In said process, a grinding system by applying pressure and temperature values in the fluid flow in the injection cooler system according to certain formulations after the esterification reaction is disclosed so as to solve the problem of agglomerate formation in granular form esters.

As a result, due to the abovementioned disadvantages and the insufficiency of the current solutions regarding the subject matter, a development is required to be made in the relevant technical field.

BRIEF DESCRIPTION OF THE INVENTION

The present invention is related to a process for preparing an appropriate composition for plastic particularly for PVC applications which fulfills the abovementioned requirements, eliminates all disadvantages and brings some additional advantages.

The main object of the invention is to provide a process that facilitates to grind the fatty acid based internal and external lubricant composition into powder form.

An object of the invention is to provide a process that eliminates the contamination of fatty acid based internal and external lubricant compositions in melt form while grinding.

Another object of the invention is to provide a process that eliminates the problems of agglomeration of fatty acid-based internal and external lubricant compositions.

Another object of the invention is to provide a process that eliminates the problem of petrification of fatty acid-based internal and external lubricant compositions.

Another object of the invention is to provide a process that grinds the fatty acid based internal and external lubricant compositions into powder form with a cost effective and efficient manner.

Another object of the invention is to provide a process that reduces the use of fillers and stabilizers in the plastic forming processes wherein fatty acid based internal and external lubricant compositions. In order to fulfill the abovementioned objects, the present invention describes a process so as to prepare a fatty acid ester-based internal or external lubricant composition for use in shaping plastics, said process comprises the following steps; subjecting at least one fatty acid or oil component with at least one alcohol component to esterification reaction under suitable conditions so as to obtain at least one fatty acid ester; adding at least one anti-agglomeration additive to the fatty acid ester obtained as a result of the reaction before grinding; and grinding the obtained mixture into powder form.

In a preferred embodiment of the invention, said fatty acid component is selected from decanoic acid, lauric acid, myristic acid, palmitic acid, pentadecanoic acid, stearic acid, arachidic acid, behenic acid, margaric acid, myristoleic acid, palmitoleic acid, oleic acid, gadoleic acid, erucic acid, ricinoleic acid, linoleic acid, licanic acid, margaroleic acid, arachidonic acid, clupanadonic acid, eicosapentaeonic acid, docosahexaenoic acid.

In a preferred embodiment of the invention, said fatty acid component is stearic acid and/or oleic acid.

In another preferred embodiment of the invention, said oil component is selected from corn oil, cottonseed oil, linseed oil, soybean oil, sunflower oil, safflower oil, canola oil and palm oil.

In another preferred embodiment of the invention, said alcohol component is selected from methanol, ethanol, pentaerythritol, tris-trimethylolpropane (TMP), sorbitol, glycerol, diglycerol, polyglycerol, or polyethylene glycol with certain molecular weights.

In another preferred embodiment of the invention, said anti-agglomeration additive is selected from fillers and/or stabilizers suitable for use in the plastic formulation.

In another preferred embodiment of the invention, said anti-agglomeration additive is selected from calcium stearate, magnesium stearate, calcite and talc.

In another preferred embodiment of the invention, said anti-agglomeration additive is selected from calcium-based stabilizers, organotin-based stabilizers and metal stabilizers. In order to fulfill the abovementioned objects, the present invention also discloses a method so as to prepare a fatty acid ester-based internal or external lubricant composition for use in shaping plastics, said method comprises the following steps; providing at least one fatty acid ester; providing at least one anti-agglomeration additive; adding said anti-agglomeration additive to said fat ester prior to grinding; and grinding the obtained mixture into powder form.

In order to fulfill the abovementioned objects, the present invention also describes a process so as to prepare a PVC formulation comprising fatty ester-based at least one internal and/or external lubricant composition, said process comprises the following steps; subjecting at least one fatty acid or oil component with at least one alcohol component to esterification reaction under suitable conditions so as to obtain at least one fatty acid ester; adding at least one anti-agglomeration additive to the fatty acid ester obtained as a result of the reaction before grinding; grinding the obtained mixture into powder form; and adding the mixture in powder form to the PVC formulation.

The structural and characteristic features of the present invention will be understood clearly by the following detailed description and therefore the evaluation shall be made by taking the detailed description into consideration.

DETAILED DESCRIPTION OF THE INVENTION

The present invention describes a process and a method so as to prepare an internal or external lubricant composition appropriate for use in plastic particularly in PVC formulations. In this detailed description a process and a method are described so as to prepare a PVC formulation comprising at least one internal and/or external lubricant composition. The preferred embodiments of the invention are described only for clarifying the subject matter in a manner such that no limiting effect is created.

In the present application, internal and external lubricant means an additive that reduces the friction between polymer-polymer, metal-metal, polymer-metal, filler-filler or polymer-filler.

In the present application, "anti-agglomeration additive" means inert organic or inorganic compounds which reduce the tendency between the particles in some products (food, medicine, paint, cosmetics, etc.) in powder form to attract each other, provide the fluidity of products with fine particles or in powder form by preventing the adhesion and prevent agglomeration tendency of the same. Also, these materials are referred to as "anti agglomeration agent", "anti-adhesion agent", "free flow agent" or "drying agent" in the literature. Said materials, that cover the particles with a thin layer, prevent the particles from adhering to each other by increasing the distance between the particles and preventing the electrostatic attraction between the particles that are oppositely charged.

In the present application, “filler substance" and "filler" are used interchangeably. Fillers are particles added to binders such as resins or plastics, composites, concrete etc. whose specific features such as tensile strength, toughness, heat resistance, color, transparency can be improved and/or which decrease the cost of the product.

In the present application "stabilizer" is used interchangeably. It refers to a class of chemical additives that is widely included in polymeric materials such as plastics so as to prevent or delay their denaturation. Polymers may be exposed to various degradation processes such as oxidation, thermal decomposition, ozonolysis, photo oxidation etc. and combinations thereof and also including catalyst residues or other impurities and reactions. Stabilizers are used to eliminate all of these disadvantages.

In the present application "fatty acid" means an acyl chain that is linked to a carboxyl functional group covalently. The fatty acid can be in the "free form" in which the carboxyl group does not form another covalent bond, or a "glyceride form" (mono-, di- and/or triglyceride) bind to glycerol.

In the present application, "percent" means percent by weight.

The present invention describes a process so as to prepare an internal or external lubricant composition for use in shaping plastics. Firstly, the synthesis of at least one fatty acid ester acting as an internal and/or external lubricant is carried out according to this process. At least one fatty acid or oil component is subjected to esterification reaction with at least one alcohol component under suitable conditions so as to synthesize fatty acid ester. The product formed as a consequence of the reaction transforms into solid form when the product cools. Among the preferred fatty acid esters of the invention the following can be listed; pentaerythritoladipatestearate, glycerolmonostearate, stearylstearate, distearylphthalate etc. include esters whose physical state is solid at room conditions. The physical state of the fatty acid ester obtained must be solid. Said fatty acid esters generally start to melt approximately at a temperature between 40-50 ° C.

After the esterification reaction is completed, the anti-agglomeration additive is added into the reaction medium while it is cooled. The anti-agglomeration additives to be used in the present invention are materials that are already used in significant ratios as fillers or stabilizers in plastic, particularly in PVC formulations. Using said anti-agglomeration additives in the plastic formulations is both useful in grinding the lubricant composition into powder form and in preventing the same from agglomeration and petrification, also eliminating the further use of said fillers or stabilizers during processing of a plastic material.

The fillers are materials that reduce the cost of the product and gives toughness to the same. The fillers that can be used as anti-agglomeration additives according to the invention include, but are not limited to, calcium stearate, magnesium stearate, calcite (calcium carbonate) and talc (magnesium hydrosilicate).

Among the stabilizers o be used as anti-agglomeration additive according to the invention can be listed as follows; calcium-based stabilizers, organotin-based stabilizers and metal stabilizers.

The anti-agglomeration additive can be added to the fatty acid ester in different ratios by weight. In preferred embodiments of the invention, 1-5% of calcium stearate, 1-5% of magnesium stearate, 10-20% of calcite or 10-20% of talc over the total weight of fatty acid ester in powder form are added.

The fatty acid ester obtained in this manner and anti-agglomeration additive mixture is transferred into the grinding system for grinding and subject to grinding until it becomes a powder. Grinding systems that can be used in a process according to the invention include, but are not limited to, types of grinding mills such as razor grinding mills, gear grinding mills, and injection cooler systems.

The "fatty acid component" used in the invention can be obtained from any fatty acid source. The physical state of the ester obtained must be solid. The fatty acids can have 10 to 22 carbon atoms that are substituted or unsubstituted, saturated or unsaturated. Preferred fatty acids are as follows; decanoic acid, lauric acid, myristic acid, palmitic acid, pentadecanoic acid, stearic acid, arachidic acid, behenic acid, margaric acid, myristoleic acid, palmitoleic acid, oleic acid, gadoleic acid, erucic acid, ricinoleic acid, linoleic acid, licanic acid, margaroleic acid, arachidonic acid, clupanadonic acid, eicosapentaeonic acid, docosahexaenoic acid, fatty acids derived from soybean, fatty acids derived from coconut, fatty acids derived from palm oil, fatty acids derived from palm kernel, fatty acids derived from tallow.

In a preferred embodiment of the invention, the fatty acid source contains oleic acid or stearic acid.

The oil components to be used in the present invention are as follows; corn oil, cottonseed oil, linseed oil, soybean oil, sunflower oil, safflower oil, canola oil and palm oil. Said oil components are preferred because they are vegetable-based and when they are decomposed, the required fatty acids are obtained.

Among the alcohol components to be used in the present invention, there are the following; methanol, ethanol, pentaerythritol, tris-trimethylolpropane (TMP), sorbitol, glycerol, diglycerol, polyglycerol, or polyethylene glycol with certain molecular weights.

Adding the anti-agglomeration additives according to the invention to the fatty acid esters in solid form after the synthesis of said esters and prior to the grinding stage with the present invention prevents the adhesion and contamination of said esters to the metal parts while they are in molten form during their grinding into powder form. When the softening temperature of fatty acid esters is at low temperature values such as between 40-60 C°, the thermal resistance of the mixture is also increased by high melting temperatures of the anti agglomeration additives according to the invention, the temperature increase depending on friction and rotation and contamination risk of the mixture on the internal surface of the equipment after it is melted are eliminated.

Moreover, as of the packing of the internal and external lubricants prepared according to the invention, during operations such as storage, transportation, keeping in stock, also agglomeration and petrification are prevented.

The lubricant compositions prepared according to the inventive process can be used in plastic polymer shaping processes. Said lubricant compositions are specifically appropriate for shaping chlorinated polymers such as polyvinyl chloride (PVC), polyvinylidine chloride and shaping the derivatives thereof as copolymers. The lubricant compositions prepared according to the inventive process can be added to plastic, for example hard or soft PVC mixtures, in varying ratios. The inventive lubricant compositions are used by adding the same into the plastic material that will be processed prior to processing. The amount of lubricant composition to be added depends on the plastic material to be processed and the type of processing. Preferably said plastic product contains lubricant composition of 0.2 to 0.6% by total weight.

As examples of the PVC products wherein the lubricant compositions prepared according to the inventive process are used, the following can be given; window profiles, automobile seat leather, floor coverings, wallpaper, shoe soles, electrical cables, and various packages.

Moreover, the lubricant compositions prepared according to the inventive process can also be used advantageously in forming all polymers which have plastic features such as polypropylene, polyethylene and are used in extrusion, injection studies and in which any lubricant is used in the formulations.

After the lubricant composition is homogeneously dispersed in the plastic, shaping process can be carried in one of the methods in known in the literature.

EXAMPLES

Pentaerythritol adipate stearate was used as fatty acid ester in the studies.

Example 1

2.12 moles (603 g) of stearic acid and 1 mole of (136.15 g) pentaerythritol and 0.645 g of PTSA as catalyst were added to a 1 liter flask with a nitrogen inlet, a mechanical stirrer inlet, a thermometer inlet and a vacuum outlet. The temperature was adjusted to 170 C°. A slight vacuum was applied to remove the formed water. The reaction continued in this way until the amount of acid decreases below 1 mg KOH/g. Then the vacuum was cut off and the temperature was reduced below 150 C°. 0.85 mol (124 g) adipic acid and 0.22 g PTSA were added into the medium. The temperature was adjusted to 170 C° again and the water formed during the reaction was removed from the medium by applying a slight vacuum. When the acid number reduces below 12 mg KOH/g, the reaction was completed, the medium was cooled and the solid product of pentaerythritol adipate stearate complex ester was achieved. Number of saponification for the obtained product is as follows: 272 mg KOH/gr, Melting Point (°C) 56-57.

Example 2

The anti-agglomeration additive was added into 1kg of pentaerythritol adipate stearate compound during the cooling phase with different percentages by weight. Prepared mixtures are given in Table I.

Table I

Example 3

The performances of pentaerythritol adipate stearate and A-F mixtures without additives were tested on a grinder. The results are summarized in the following.

- Melting and adhesion was observed immediately when pentaerythritol adipate stearate itself was taken into the grinder without adding any additives.

- When the mixture A was taken into the grinder, melting and adhering was not seen on the razor of the grinder for a certain period of time. While the process continued, slight melting and adhesion started on the razor.

- When the mixture B was taken into the grinder, no melting and no adhering was seen on the razor of the grinder and thus powder form is obtained.

- When the mixture C was taken into the grinder, melting and adhering was not seen on the razor of the grinder for a certain period of time. While the process continued, slight melting and adhesion started on the razor. - When the mixture D was taken into the grinder, no melting and no adhering was seen on the razor of the grinder and thus powder form is obtained.

- When the mixture E was taken into the grinder, melting and adhering was seen on the razor of the grinder after a short period of time.

Claims

1. A process for preparing prepare a fatty acid ester-based internal or external lubricant composition for use in shaping plastics, characterized in that, it comprises the following steps;

- esterification of at least one fatty acid or oil component with at least one alcohol component under suitable conditions to obtain at least one fatty acid ester;

- adding at least one anti-agglomeration additive to the fatty acid ester obtained from the reaction before grinding; and grinding the obtained mixture into powder form.

2. Process according to claim 1 , characterized in that; said fatty acid component is selected from decanoic acid, lauric acid, myristic acid, palmitic acid, pentadecanoic acid, stearic acid, arachidic acid, behenic acid, margaric acid, myristoleic acid, palmitoleic acid, oleic acid, gadoleic acid, erucic acid, ricinoleic acid, linoleic acid, licanic acid, margaroleic acid, arachidonic acid, clupanadonic acid, eicosapentaeonic acid, docosahexaenoic acid.

3. Process according to claim 2, characterized in that; said fatty acid component is stearic acid and/or oleic acid.

4. Process according to any of the previous claims, characterized in that; said oil component is selected from corn oil, cottonseed oil, linseed oil, soybean oil, sunflower oil, safflower oil, canola oil and palm oil.

5. Process according to any of the previous claims, characterized in that; said alcohol component is selected from methanol, ethanol, pentaerythritol, tris-trimethylolpropane (TMP), sorbitol, glycerol, diglycerol, polyglycerol, or polyethylene glycol with certain molecular weights.

6. Process according to any of the previous claims, characterized in that; said anti agglomeration additive is selected from fillers and/or stabilizers suitable for use in the plastic formulation.

7. Process according to claim 6, characterized in that; said anti-agglomeration additive is selected from calcium stearate, magnesium stearate, calcite and talc.

8. Process according to claim 6, characterized in that; said anti-agglomeration additive is selected from calcium-based stabilizers, organotin-based stabilizers and metal stabilizers.

9. A method for preparing a fatty acid ester-based internal or external lubricant composition for use in shaping plastics, characterized in that, it comprises the following steps;

- providing at least one fatty acid ester;

- providing at least one anti-agglomeration additive;

- adding said anti-agglomeration additive to said fat ester prior to grinding; and grinding the obtained mixture into powder form.

10. Method according to claim 9, characterized in that; the physical state of said fatty acid ester is solid at room conditions.

11 . Method according to claim 10, characterized in that; said fatty acid ester is selected from pentaerythritol adipate stearate, glycerolmonostearate, stearylstearate and distearylphthalate.

12. Method according to claims 9 to 11 , characterized in that; said anti-agglomeration additive is selected from fillers and/or stabilizers suitable for use in the plastic formulations.

13. Method according to claim 12, characterized in that; said anti-agglomeration additive is selected from calcium stearate, magnesium stearate, calcite and talc.

14. Method according to claim 12, characterized in that; said anti-agglomeration additive is selected from calcium-based stabilizers, organotin-based stabilizers and metal stabilizers.

15. A process for preparing a PVC formulation comprising fatty ester-based at least one internal and/or external lubricant composition, characterized in that; said method comprises the following steps;

- adding at least one anti-agglomeration additive to the fatty acid ester obtained from the reaction before grinding; grinding the obtained mixture into powder form; and adding the mixture in powder form to the PVC formulation.

16. Process according to claim 15, characterized in that; said fatty acid component is selected from decanoic acid, lauric acid, myristic acid, palmitic acid, pentadecanoic acid, stearic acid, arachidic acid, behenic acid, margaric acid, myristoleic acid, palmitoleic acid, oleic acid, gadoleic acid, erucic acid, ricinoleic acid, linoleic acid, licanic acid, margaroleic acid, arachidonic acid, clupanadonic acid, eicosapentaeonic acid, docosahexaenoic acid.

17. Process according to claim 16, characterized in that; said fatty acid component is stearic acid and/or oleic acid.

18. Process according to claims 15 to 17, characterized in that; said oil component is selected from corn oil, cottonseed oil, linseed oil, soybean oil, sunflower oil, safflower oil, canola oil and palm oil.

19. Process according to claims 15 to 18, characterized in that; said alcohol component is selected from methanol, ethanol, pentaerythritol, tris-trimethylolpropane (TMP), sorbitol, glycerol, diglycerol, polyglycerol, or polyethylene glycol with certain molecular weights.

20. Process according to claims 15 to 19, characterized in that; said anti-agglomeration additive is selected from fillers and/or stabilizers suitable for use in the plastic formulation.

21 . Process according to claim 20, characterized in that; said anti-agglomeration additive is selected from calcium stearate, magnesium stearate, calcite and talc.

22. Process according to claim 20, characterized in that; said anti-agglomeration additive is selected from calcium-based stabilizers, organotin-based stabilizers and metal stabilizers.

23. Method for preparing a PVC formulation comprising fatty ester-based at least one internal and/or external lubricant composition, characterized in that; the method comprises the following steps;

- providing at least one fatty acid ester as an internal and/or external composition; - providing at least one anti-agglomeration additive;

- adding at least one anti-agglomeration additive to the fatty acid ester obtained from the reaction before grinding; and grinding the obtained mixture into powder form; and - adding the mixture in powder form to the PVC formulation.

24. Method according to claim 23, characterized in that; the physical state of said fatty acid ester is solid at room conditions.

25. Method according to claim 24, characterized in that; said fatty acid ester is selected from pentaerythritol adipate stearate, glycerolmonostearate, stearylstearate and distearylphthalate.

26. Method according to claims 23 to 25, characterized in that; said anti-agglomeration additive is selected from fillers and/or stabilizers suitable for use in the PVC formulation.

27. Method according to claim 26, characterized in that; said anti-agglomeration additive is selected from calcium stearate, magnesium stearate, calcite and talc.

28. Method according to claim 26, characterized in that; said anti-agglomeration additive is selected from calcium-based stabilizers, organotin-based stabilizers and metal stabilizers.