WO2016153455A1

WO2016153455A1 - Method of obtaining a coal pitch polymeric thermoplastic composition

Info

Publication number: WO2016153455A1
Application number: PCT/UA2015/000024
Authority: WO
Inventors: Sergiy MEDYANTSEV; Oleksandr RYZHENKOV; Anatolii KOMAROV; Valeriy KHILKO
Original assignee: Medyantsev Sergiy; Ryzhenkov Oleksandr; Komarov Anatolii; Khilko Valeriy
Priority date: 2015-03-20
Filing date: 2015-03-20
Publication date: 2016-09-29

Abstract

The invention is related to the field of processing of high temperature coal pitch, in particular, to the method of obtaining coal pitch polymeric thermoplastic composition, wherein high temperature coal pitch is mixed with polyvinyl chloride, a compatibilizer representing a complex of grafted copolymers of ethylene vinyl acetate, polyethylene and acrylonitrile butadiene styrene, a plasticizer, a filler and targeted additives, the mixture is stirred under exothermic reaction conditions to the temperature of 115 - 125 °C, with subsequent cooling to the temperature of 40 - 45 °C. The obtained coal pitch polymeric thermoplastic composition can be used in the manufacture of construction articles for general technical as well as engineering and technical purposes, in particular, for use in the manufacture of pipes for various purposes, composite shaped articles, and other high strength, corrosion-resistant articles with the use of extrusion method.

Description

METHOD OF OBTAINING A COAL PITCH POLYMERIC THERMOPLASTIC

COMPOSITION

Field of the Invention

The invention relates to the field of coal pitch processing and can be used in the manufacture of construction articles for general technical as well as engineering and technical purposes, in particular, for use in manufacture o f pipes for various purposes, composite shaped articles and other high strength, corrosion-resistant articles with the use of extrusion method.

Background of the Invention

A method of obtaining a thermoplastic composition based on coal pitch for the manufacture of polymeric fibre-glass pipes is known, the method comprises mixing of high temperature coal pitch with plasticizer and a mineral filler, the second and the third anthracene fractions are taken as plasticizer instead of bitumen, as bitumen will not be combined with high temperature coal pitch, and such mass tends to flaking off on cooling, the preferable temperature within a mixer being 200 to 230 °C. The process of preparing the composition comes down to complete wetting a filler (kaolin) with plasticized coal pitch and formation of homogeneous mass, which is mobile at a temperature of 140 - 160 °C [ ripnBajiOB B.B., C enaHeHKO M.J1. KaMeHH oyrojib Hbiii πεκ , M. : Me ajiJiyp rM^ , 1981 r., οτρ. 139, 167 - 170 (Privalov V.B., Stepanenko M.L. Kamennougolny pek, M . : Metallurgiya, 1981, pages 139, 167 - 170) ] . Drawbacks of the known method include high temperatures of the process, the necessity in multiple stages thereof, long duration, the emission of hazardous volatile compounds due to the use of the second and the third anthracene fractions as a plasticizer, with their high content of hazardous polycondensated aromatic compounds (20 - 40% of pitch weight ) .

The closest to the claimed invention, by its technical essence, is a method of obtaining a coal pitch polymeric thermoplastic composition [Ukrainian Patent for Invention No. 98286, IPC class CIOC 3/00, published on 25.04.2012], the method includes mixing of coal pitch with plasticizer and mineral filler, wherein medium temperature coal pitch is taken and initially mixed with polyvinyl chloride, and then with a modified ethylene - vinyl acetate copolymer as a plasticizer, the thus obtained mixture is admixed with chrysotile as a fibrous mineral filler, the mixture is stirred, warmed to the temperature of 150 to 170 °C and held at this temperature till formation of a homogeneous mass with the following component ratio, in parts by weight:

Drawbacks of the known method include low thermal stability of articles made of the proposed composition (72 - 80 °C according to Vicat test) and, accordingly, impossibility of production of articles providing for the use at elevated temperatures, for example pipes for hot water and heating systems, which fact substantially limits a field of use thereof. Summary of the Invention

The invention is based on the object of obtaining a coal pitch polymeric thermoplastic composition, which would be free of drawbacks of prior art composition. As a result of numerous experiments, the inventors have obtained a coal pitch polymeric thermoplastic composition, component ratio of which provided for achievement of said technical object, i.e. higher thermal stability of articles made of a coal pitch polymeric composition, without loss of their high mechanical strength.

The specified object is achieved according to the method of obtaining the coal pitch polymeric thermoplastic composition, wherein coal pitch is mixed with polyvinyl chloride, a plasticizer, a filler and targeted additives, the obtained mixture is warmed and then cooled, wherein a high temperature coal pitch is used as a coal pitch, the mixture is admixed with a compatibilizer representing a complex of grafted copolymers of ethylene vinyl acetate, polyethylene and acrylonitrile butadiene styrene, the mixture is stirred under exothermic reaction conditions to the temperature of 115 - 125 °C, with subsequent cooling to the temperature of 40 - 45 °C.

In the preferred embodiment, component ratio of the composition is as follows, in % by weight:

High temperature coal pitch 45 - 70;

Polyvinyl chloride 15 - 30;

Compatibilizer 2 - 5;

Plasticizer 4 - 7;

Filler 4 - 10;

Targeted additives 2 - 6. In one of the preferred embodiments of the invention the complex of grafted copolymers of ethylene vinyl acetate, polyethylene and acrylonitrile butadiene styrene represents a grafted copolymer known as "LARTEN Complex". In further preferred embodiment of the invention, plasticizer is dioctyl phthalate, trioctyl trimellitate, dipropylheptyl phthalate, dioctyl adipate, diisononyl phthalate or diisodecyl phthalate, and/or any combination thereof, preferably dioctyl phthalate. In still further preferred embodiment of the invention, the targeted additive represents Ca stearate, Zn stearate, Na stearate, wax, and/or a mixture thereof with any component ratio .

In still further preferred embodiment of the invention, the filler is selected from hydrates, oxides, clays, carbonates, silicates, dolomite, or mixture of said substances, chrysotile and/or chalk being preferable fillers.

In an additional embodiment, the invention refers to the coal pitch polymeric thermoplastic composition obtainable according to the claimed method of obtaining.

In an additional embodiment, the invention refers to the article obtainable from the claimed coal pitch polymeric thermoplastic composition (Pekoplast).

In still further preferred embodiment of the invention, the article is a pipe for various purposes, a drain cover, a sink drain element, and a nondisposable pallet made of the coal pitch polymeric thermoplastic composition. It should also be noted that the material for manufacture of pipes must have a high impact stability and chip resistance, and softening temperature of at least 90 °C to be used in hot water supply.

In still further preferred embodiment of the invention, the article is manufactured from the coal pitch polymeric thermoplastic composition by extrusion.

Detailed Description of the Invention

For the purposes of the present invention, it should be understood that coal pitch means a material, which represents a solid derivative product of coal tar resin. Visually homogeneous, thermoplastic black substance with a glossy shell-like fracture, and having the following elemental formulation (%): C 92 - 93, H 4.3 - 4.7, S 0.3 - 0.85, N 1.7 - 1.8, and O 0.8 - 1.0; density of 1.2 - 1.3 g/cm³, and ash content of 0.2 - 0.3%, and having no definite melting and solidification temperatures; it is melted within the range characterized by the softening temperature.

There are medium temperature coal pitch (softening temperature of 65 - 90 °C; flash point 200 - 250 °C; 53 - 63% yield of volatile matter formed during thermodynamic decomposition, and high temperature coal pitch (135 - 150 °C; 360 - 400 °C; and 43 - 54%, accordingly) .

Production of the high temperature pitch is achieved by distillation of the medium temperature pitch with water steam or inert gases and air processing in the amount of 100 - 130 m³/t of pitch at a temperature of 370 - 380 °C and contact time of 12 - 14 hours. In this process lighter components are distilled off the medium temperature pitch. In the course o f thermal processing of the medium temperature pitch in the presence of air, new densifying products are formed as a result of oxidative dehydropolycondensation . Softening temperature of pitch rises to 135 - 150 °C ( ripMBajioB B.B., CTenaHeHKO M.J1. KaMeHHoyrojibHbM ΠΘΚ. - M . : Me ajuiyprMH , 1981 r . , C. 139, 167 - 170 (Privalov V.B., Stepanenko M.L. Kamennougolny pek. - M. : Metallurgiya, 1981, pages 139, 167 - 170) ) . For the purposes of the present invention, the high temperature coal pitches may be used, for example, those obtainable at the coking plants of Ukraine, in particular, at Gorlovka Coking Plant (OJSC "Smolopererabatyvayushchiy Zavod", Ukraine) . Softening temperature of the high temperature pitch obtained at the Gorlovka Coking Plant is 135 - 160 °C, ash content is 0.07 - 0.19%, and humidity is 1.4 - 2.0%.

In the preferred embodiment, 45 to 70 % by weight of the high temperature coal pitch is used to obtain the coal pitch polymeric thermoplastic composition according to the invention .

Polyvinyl chloride is a colourless, transparent plastic, thermoplastic vinyl chloride polymer. It is characterized by chemical stability to alkali, mineral oils, many acids and solvents.

As PVC, for example, polymers from such companies as Larta (Belarus), Hydro Polymers (Norway) , Ineos (Switzerland) , Georgia Gulf (USA) or Solvin (Belgium) may be used . In the preferred embodiment, 15 to 40 % by weight of polyvinyl chloride is used to obtain the coal pitch polymeric thermoplastic composition according to the invention.

It should be understood for the purposes of the present invention that compatibilizers mean substances intended for the formation of strong bonds at the "filler - polymer" interface, said substances being obtained on the basis of non-polar polymers, such as polypropylene, polyethylene and EVA or ABS copolymers, to which maleic anhydride (in the amount of 0.5 to 1.5%) or acrylic acid (about 6%) are grafted, with active functional groups. Such compounds are used in the production of composition polymeric materials filled with glass fibres (short and long), mineral (talc, mica, wollastonite and chalk) and wood filler, cellulose or halogen-free antipyrenes, such as aluminium and magnesium hydroxides.

Particularly efficient compatibilizers for providing compatibility of the high temperature coal pitch and polyvinyl chloride and increase of impact viscosity of Pekoplast are those based on the mixture of grafted EVA (ethylene vinyl acetate) , PE (polyethylene) and ABS ( acrylonitrile butadiene styrene) , with functional groups grafted thereto by reaction extrusion.

Mechanism of action of compatibilizer is that the grafted copolymer based on EVA, PE and ABS is thermodynamically related to polymer (PVC) being filled and is well compatible with it. At the same time, compatibilizer, by means of active functional groups, forms strong bonds with pitch and fibrous filler (chrysotile) also having active functional groups, thereby preventing from delamination of the material and forming its spatial structure.

The use of compatibilizer in the amount of 2 to 10% allows to remove negative effects arising in cases of combining the high temperature coal pitch and PVC (laminated structure of material and brittleness and aggressive odour attributable thereto) and obtain high quality, highly filled composition providing for the necessary level of physical and mechanical properties and rheological characteristics of the compositions. Polymeric compositions of PVC with the high temperature coal pitch are thereby rendered more resilient and capable of deforming under the action of mechanical stress without brittle rupture, more resistant to impact loading and stronger, the aggressive inherent for characteristic of coal pitch disappears.

In the preferred embodiment, 2 to 10 % by weight of compatibilizer is used, preferably a graft copolymer based on the mixture of grafted EVA, PE and ABS, in more preferred embodiment grafted copolymer "LARTEN Complex" from ALC "Research and Development Center LARTA" (Belarus) to obtain the coal pitch polymeric thermoplastic composition according to the invention.

As a plasticizer, according to the present invention, plasticizers usable in combination with PVC are used. Examples of such plasticizers include, for example, dioctyl phthalate, trioctyl trimellitate , dipropylheptyl phthalate, dioctyl adipate, diisononyl phthalate or diisodecyl phthalate, and/or any compatible combination thereof, in particular, dioctyl phthalate being preferable as a plasticizer .

In the preferred embodiment, 2 to 7 % by weight of plasticizer is used to obtain the coal pitch polymeric thermoplastic composition according to the invention. According to the present invention, for example, materials selected from hydrates, oxides, clays, carbonates, silicates, dolomite or mixture of the mentioned substances may be used as fillers, preferable filler being chrysotile and/or chalk. Chrysotile, due to its fibrous structure, represents a reinforcing mineral filler and provides for high strength and flexibility. Its active functional hydroxyl groups form strong bonds with polar groups of a coal pitch polymeric matrix. As a result of interphase interaction, strong bonds are formed at the pitch polymer <→ filler polymer borderline, with substantially improved adhesion of coal pitch polymer with a mineral filler, which provides for high strength of material thus obtained. Furthermore, chrysotile in a coal pitch polymeric thermoplastic composition may function as a halogen-free antipyrene, because at a temperature of above 300 °C it is capable of evolving water vapours. Fire behaviour of Pekoplast also decreases a content of chlorine- containing substances therein, thermal decomposition of said substances being accompanied with the formation of radicals that transform active oxygen-containing fragments (RO and OH) that are formed during combustion into less active and stable molecules (RX or H₂0) . Chlorine-containing substances also promote coke production, with a resulting self-quenching effect. Therefore, Pekoplast takes on the properties of an incombustible material. Chalk, as a mineral filler, represents a natural material in the form of sedimentary rock, or it may be obtained chemically from calcium-containing compounds. It has high dispersability, low hygroscopicity and low abrasivity.

In the preferred embodiment, 2 to 10% by weight of filler is used, preferably chrysotile and/or chalk, to obtain the coal pitch polymeric thermoplastic composition according to the invention.

As targeted additives, according to the present invention, Ca stearate, Zn stearate, Na stearate, wax, and/or a mixture thereof are used with any component ratio. Targeted additives are used as stabilizers of chemical stability, as well as modifiers that confer certain properties to final materials .

In the preferred embodiment, 4 to 20 % by weight of targeted additives is used to obtain the coal pitch polymeric thermoplastic composition according to the invention.

The method of obtaining the coal pitch polymeric thermoplastic composition provides for the following order of operations .

The pre-milled high temperature coal pitch is charged into a mixer, then polyvinyl chloride, compatibilizer , as a crosslinking agent between macromolecules of coal pitch and polyvinyl chloride, dioctyl phthalate a s a plasticizer, chrysotile as a fibrous mineral filler or chalk as a mineral filler (depending on the intended use of articles made of the composition) and targeted additives are added, the components are stirred in the mixer under exothermic reaction conditions till the temperature reaches 115 - 125 °C, then the obtained mixture is transferred to a cooled mixer and mixing is continued to cooling the resulting composition to 40 - 45 °C. The resulting powdered composition of coal pitch polymer is charged into an extruder for the manufacture of articles. Production of articles with the use of an extruder is well known in the art of plastics processing and described, for example, in Β . Π . BOJIO^MH "3κο ργ3Μ« npocJmjibHbix M3¾ejiM¾ M3 TepMonjia cTO B " , H3fl-BO " npo<J>ecci/i« " , CaHKT-neTepbypr, 2005 r. (V.P. Volodin "Ekstruziya profilnykh izdeliy iz termoplastov" , "Professiya" , Saint-Petersburg, 2005) .

Cause-and-effect relation between plurality of the essential features of the claimed invention and the obtainable technical result is as described below. When components are stirred in the mixer, the mixture passes to the state of exothermic reaction and is held in such state till the temperature reaches 115 - 125 °C, without passing to liquid state (up to charging into an extruder the mixture must remain in a powdered state) and herewith, due to compatibilizer, the composition provides a modifying effect because of formation of stronger bonds at the interphase boundary: filler polymer (polyvinyl chloride) <→ compatibilizer <→ coal pitch polymer (high temperature coal pitch) , as well as at the interphase boundary between polymers in a mixed polymeric material. At the second stage the obtained mixture is transferred to a cooled mixer and stirring is continued till the temperature of the mixture reaches 40 - 45 °C, then the resulting mixture in a powdered state is charged into an extruder for the manufacture of end products .

Thus, as a result of complex physicochemical transformations and interphase interactions within the system of the high temperature coal pitch - polyvinyl chloride - compatibilizer - filler - targeted additives the incombustible thermoplastic coal pitch polymeric composition is formed having high strength. The claimed component ratio is necessary and sufficient for solution of the set task.

Practical Embodiment of the Invention.

Materials

High temperature coal pitch having a softening temperature of 135 - 160 °C was purchased from Metinvest Company, Avdeyevka Coking Plant. Polyvinyl chloride as a white powder with a particle size of 100 - 200 μπι, density of 1380 - 1400 kg/m³, was purchased from the company "Halych-Kabel" Private Enterprise.

Compatibilizer as a grafted copolymer "LARTEN Complex" manufactured in accordance with TU 49032155 .0010Π-2013 , was purchased from the company ALC "Research and Development Center LARTA" (Belarus) .

Plasticizer, dioctyl phthalate with a density of 20 °C in the range of 0.982 - 0.986 g/cm³, and a weight fraction of volatile substances less than or equal to 0.1%, was purchased from the company "Krasitel", Rubezhnoye.

Filler, chrysotile, short-fibered natural mineral, hydrated magnesium silicate with a density of 2,400 - 2,600 kg/m³, was purchased from the company PJSC "MAKEYEVKOKS" . Filler, chalk, natural material, white, soft and friable, water-insoluble sedimentary rock of organic (zoogenic) origin, having high dispersability, low hygroscopicity and low abrasivity, was purchased from the company LLC "Plasten". Targeted additives as a mixture of Ca, n, Na stearates and wax, was purchased from the company LLC "Severodonetskoye NPO "Khimresurs" .

Tes Methods

Testing of the obtained samples for maximum tension stress was carried out according to GOST 11262-80 for plastics using the method of tension test.

Testing of the obtained samples for softening temperature of sample material was carried out according to GOST 15088-83 for plastics using the method of determining Vicat softening point for thermoplastics.

Example 1

SRL-Z mixer ( Zhangj iagang Yisu Machinery Co., Ltd., People' s Republic of China) was charged with 70 g of pre- milled high temperature coal pitch, 15 g of PVC, 2 g of "LARTEN Complex" compatibilizer, 4 g of chalk, 7 g of dioctyl phthalate, 2 g of a target additive (mixture of Ca stearate, Zn stearate, Na stearate and wax) . When mixture components were stirred, exothermic reaction took place with increase of the mixture temperature till it reached 115 - 125 °C, then the resulting mixture was transferred to a cooled mixer, and stirring was continued to the temperature of 40 - 45 °C. The obtained formulation in a powdered state was loaded into SRL- Z 500/1000 twin screw extruder ( Zhang iagang Yisu Machinery Co., Ltd., People's Republic of China) and heated, the thermoplastic polymer successively passed from a solid powdered state to a molten state, and then again to a solid state after leaving a forming equipment. In testing the obtained sample maximum tension stress was 15 MPa, and softening temperature of the coal pitch polymeric thermoplastic composition for the production of a sample was 90 °C.

Example 2 Manufacturing technique was similar to that described in

Example 1, with the use of the following components in the following amounts: 45 g of pre-milled high temperature coal pitch, 30 g of PVC, 5 g of "LARTEN Complex" compatibilizer, 10 g of chalk, 4 g of dioctyl phthalate, 6 g of a target additive (mixture of Ca stearate, Zn stearate, Na stearate and wax) . In testing the obtained sample maximum tension stress was 20 MPa, and softening temperature of the coal pitch polymeric thermoplastic composition was 85 °C.

Example 3 (comparative, according to the Patent of Ukraine No. 98286)

32 g (64 % by weight) of pre-milled medium temperature coal pitch was mixed with 1.5 g (3 % by weight) of modified ethylene - vinyl acetate copolymer, 1.5 g (3 % by weight) of PVC and 15 g (30 % by weight) of chrysotile. The mixture was thoroughly stirred. The obtained mixture was placed into a reactor prewarmed to 160 °C. After melting the components of the mixture, the mixer was switched on and the mixture was held till obtaining a homogeneous mass, whereafter it was discharged and samples were formed. The results of testing the obtained sample were as follows: maximum tension stress was 10 MPa, and softening temperature of the coal pitch polymeric thermoplastic composition was 78 °C.

Example 4 (comparative) Manufacturing technique was similar to that described in

Example 1, with the use of the following components in the following amounts: 60% of pre-milled medium temperature coal pitch, 20% of PVC, 5% of "LARTEN Complex" compatibilizer , 5% of chrysotile, 4% of dioctyl phthalate, 6% of targeted additives (mixture of Ca stearate, Zn stearate, Na stearate and wax) .

The results of testing the obtained sample were as follows: maximum tension stress was 18 MPa, and softening temperature of the coal pitch polymeric thermoplastic composition was 80 °C. Example 5

Manufacturing technique was similar to that described in Example 1, with the use of the following components in the following amounts: 60% of pre-milled of high temperature coal pitch, 25% of PVC, 5% of chrysotile, 4% of dioctyl phthalate, 6% of targeted additives (mixture of Ca, Zn and Na stearates and wax) .

The results of testing the obtained sample were as follows: maximum tension stress was 15 MPa, and softening temperature of the coal pitch polymeric thermoplastic composition was 85 °C.

Example 6

Manufacturing technique was similar to that described in Example 1, with the use of the following components in the following amounts: 60 g of pre-milled high temperature coal pitch, 20 g of PVC, 5 g of "LARTEN Complex" compatibilizer , 5 g of chrysotile, 4 g of dioctyl phthalate, 6 g of a target additive (mixture of Ca, Zn and Na stearates and wax) .

In testing the obtained sample maximum tension stress was 30 MPa, and softening temperature of the coal pitch polymeric thermoplastic composition was 95 °C.

The test results for the above examples are summarized in Table 1. Table 1

* according to the Patent of Ukraine No. 98286 "Method of Obtaining a Coal Pitch Polymeric Thermoplastic

Composition On the basis of the obtained data, it can be concluded that the most successful material in terms of its tensile strength and softening point is the material of Example 6. Pipes manufactured from the material of Example 6 are both impact resistant and tensile strong, they have softening temperature of 95 °C and can be used in housing and utility sector for heating.

Comparison of the materials of Examples 6 and 3 has revealed fundamental differences between the obtained products. Inclusion of "LARTEN Complex" to the composition as compatibilizer (Example 4) has not either provided for desirable characteristics of the material obtained from the medium temperature pitch. Pipes manufactured by extrusion method from the material of Example 3 had poor characteristics of an ultimate tensile strength and low softening temperature, which made them unsuitable for use in hot water transportation, including the use in housing and utility sector heating systems. Pipes manufactured by extrusion method from the material of Example 4, do not either meet the requirement for the desired softening point.

High degree of oxidation of the high temperature pitch increases the softening point thereof to 135 - 150 °C, which, accordingly, has also an effect on the softening temperature of end products made therefrom. However, as demonstrated by the results, such high degree of oxidation significantly lowers mechanical strength properties of the material.

Achievement of high characteristics in terms of tensile strength and softening point of material has become possible only with the use of additional compatibilizer in the composition of the high temperature pitch, said compatibilizer consisting of the mixture of grafted EVA, PE and ABS . The mentioned compatibilizer is well compatible with PVC and, at the same time, due to the presence of functional groups, forms strong bonds with the high temperature pitch, which also has active functional groups. Combination of the active functional groups of compatibilizer and the pitch excludes delamination of the pitch and forms a single spatial structure of material.

Claims

1. A method of obtaining a coal pitch polymeric thermoplastic composition, wherein coal pitch is mixed with polyvinyl chloride, a plasticizer, a filler and targeted additives, the obtained mixture is warmed and then cooled, characterized in that a high temperature coal pitch is used as a coal pitch, the mixture is admixed with a compatibilizer representing a complex of grafted copolymers of ethylene vinyl acetate, polyethylene and acrylonitrile butadiene styrene, the mixture is stirred under exothermic reaction conditions to the temperature of 115 - 125 °C, with subsequent cooling to the temperature of 40 - 45 °C.

2. The method according to claim 1, characterized in that the component ratio of the mixture, in % by weight, is as follows:

3. The method according to claims 1 or 2, characterized in that the compatibilizer represents a grafted copolymer "LARTEN Complex".

4. The method according to any one of claims 1 to 3, characterized in that the plasticizer is dioctyl phthalate, trioctyl trimellitate, dipropylheptyl phthalate, dioctyl adipate, diisononyl phthalate or diisodecyl phthalate, and/or a combination thereof.

5. The method according to claim 4, characterized in that the plasticizer is dioctyl phthalate.

6. The method according to any one of claims 1 to 5, characterized in that the targeted additive is Ca stearate, Zn stearate, Na stearate, wax, and/or a mixture thereof.

7. The method according to any one of claims 1 to 6, characterized in that the filler is selected from hydrates, oxides, clays, carbonates, silicates, dolomite, and/or a mixture thereof.

8. The method according to claim 7, characterized in that the filler is chrysotile and/or chalk.

9. A coal pitch polymeric thermoplastic composition obtained by the method according to any one of claims 1 to 8.

10. An article obtained from the coal pitch polymeric thermoplastic composition according to claim 9.

11. The article according to claim 10, characterized in that it is a pipe.

12. The article according to claim 11, characterized in that it is manufactured by extrusion method.