Crystallization-improved polybutene materials and their applications

Abstract

This invention discloses a crystallization-improved polybutene material and its applications. The raw materials, by weight, include 100 parts polybutene and 1-10 parts PB-based masterbatch. The PB-based masterbatch raw materials, by weight, include 100 parts PB-based masterbatch carrier resin, 10-100 parts masterbatch component resin, 6-40 parts dispersing component, and 0.5-10 parts nucleating agent. This invention discloses a crystallization-improved polybutene material capable of producing crystallization-improved polybutene pipes. While ensuring pipe performance, it shortens the crystal transformation time, which is of significant importance to production practice.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of high molecular pipe material, in particular to a crystallization-improved polybutene material and application. BACKGROUND

[0002] Polybutene-1 has excellent heat creep resistance, chemical stability, environmental stress cracking resistance and excellent toughness, and is known as plastic gold. In recent years, its application in the heating field in China has been growing. PB-1 is a typical polymorphic semi-crystalline polymer, which has four different crystal forms: I, II, III, and I'. Only the tetragonal crystal form II with 11 / 3 helical conformation and the hexagonal crystal form I with 3 / 1 helical conformation have practical significance for industrial production. The polybutene pipe material just off the line in industrial production is in metastable state crystal form II. According to the requirements of GB / T 19473.2-2020, the polybutene pipe material just off the line needs to be aged at room temperature for not less than 120h, and the crystal form is changed to stable crystal form I, at which time the pipe material size is shrunk and shaped.

[0003] In the prior art, the crystal form transformation time is long, which greatly prolongs the production cycle. Therefore, a processing method capable of shortening the crystal form transformation time and thus shortening the pipe material production cycle is particularly important.

[0004] In view of this, the present application is proposed. SUMMARY

[0005] The purpose of the present application is to provide a crystallization-improved polybutene material, a processing method of crystallization-improved polybutene pipe material, and application of the crystallization-improved polybutene material in polybutene pipe material.

[0006] The present application is realized as follows:

[0007] In a first aspect, the present application provides a crystallization-improved polybutene material, the raw materials of which include 100 parts of polybutene and 1-10 parts of PB-based master batch by weight.

[0008] The raw materials of the PB-based master batch include 100 parts of PB-based master batch carrier resin, 10-100 parts of master batch component resin, 6-40 parts of dispersion component, and 0.5-10 parts of nucleating agent by weight.

[0009] In an optional embodiment, the raw materials of the PB-based master batch satisfy at least one of the following ①-⑨;

[0010] ①The PB-based master batch carrier resin is polybutene with a melt index of 0.5-5g / 10min at 190℃ under a load of 2.16kg;

[0011] ii) the masterbatch component resin is polybutylene having a melt index of 0.5-5 g / 10 min at 190°C under a load of 2.16 kg;

[0012] iii) the PB-based masterbatch carrier resin is polybutylene having a melt index of 0.5-2 g / 10 min at 190°C under a load of 2.16 kg;

[0013] iv) the masterbatch component resin is polybutylene having a melt index of 0.5-2 g / 10 min at 190°C under a load of 2.16 kg;

[0014] v) the PB-based masterbatch carrier resin has a higher melt index than the masterbatch component resin under the same test conditions;

[0015] vi) the dispersing component comprises, by weight, 1-10 parts of PP wax and 5-30 parts of dispersant, the PP wax being at least one of polypropylene wax, propylene-ethylene copolymer wax, maleic anhydride grafted polypropylene wax, and maleic anhydride grafted propylene-ethylene copolymer wax;

[0016] vii) the dispersing component comprises, by weight, 1-10 parts of PP wax and 5-30 parts of dispersant, the dispersant being at least one of aliphatic amide dispersant, fatty acid ester dispersant, saturated hydrocarbon dispersant, and metal soap dispersant; the aliphatic amide dispersant being ethylene bis-stearamide and / or oleic amide; the fatty acid ester dispersant being pentaerythritol stearate and / or glycerol monostearate; the saturated hydrocarbon dispersant being polyethylene wax; and the metal soap dispersant being calcium stearate and / or zinc stearate;

[0017] viii) the nucleating agent is at least one of inorganic small molecule, inorganic salt, inorganic oxide nucleating agent such as sodium benzoate, talc, carbon black, inorganic pigment, aluminum oxide, calcium sulfate, calcium silicate, yttrium oxide, sorbitol nucleating agent, aromatic-substituted phosphate nucleating agent, metal phosphate nucleating agent, metal carboxylate nucleating agent, rosin nucleating agent, condensed ring compound nucleating agent such as γ-quinacridone, triphenyl dithiazine, indigo gray, indigo golden yellow, indigo brown, Ciba blue, organic acid and its salt nucleating agent such as pimelic acid and its salt, suberic acid and its salt, glutaric acid and its salt, amide nucleating agent such as N,N'-dicyclohexyl terephthalamide, N,N'-dicyclohexyl-2,6-naphthalene dicarboxamide, rare earth nucleating agent such as rare earth polybasic complex or double complex of rare earth and Group ⅡA metal;

[0018] ⑨ The PB-based masterbatch carrier resin is Koattro KT MR 05, the masterbatch component resin is Akoafloor PB 4235-1, the PP wax is Licocene PP 3602, the dispersant is KAO WAXEB-FF, and the nucleating agent is TMB-5.

[0019] Secondly, the present invention provides a method for processing polybutene pipes with improved crystallinity, wherein the polybutene and PB-based masterbatch described in the foregoing embodiments are mixed evenly and then processed using an extruder to obtain polybutene pipes.

[0020] In an optional embodiment, the PB-based masterbatch is granulated by uniformly mixing the dispersing component and nucleating agent, then uniformly mixing the PB-based masterbatch carrier resin and masterbatch component resin, and finally extruding the mixture.

[0021] In an optional embodiment, the granulation step is performed by air-cooled die-cutting extrusion granulation, and the temperature range of the granulation step is 120-180℃.

[0022] In an optional embodiment, the extruder head is sequentially connected to a first vacuum cooling box, a heating assembly, and a second vacuum cooling box.

[0023] In an optional embodiment, the heating assembly includes two or more heating zones arranged along the material movement direction, and the temperature of the two or more heating zones is reduced from 110-120°C to 80-90°C.

[0024] Preferably, the heating assembly includes a protective cover, on which a pipe inlet, a pipe outlet, and an air outlet are provided.

[0025] In an optional embodiment, the first vacuum cooling box includes an immersion cooling section and a spray cooling section. The spray cooling section is provided with two or more spray heads, and each spray head is provided with a control device that can adjust the flow rate and water temperature.

[0026] Preferably, the second vacuum cooling box is cooled by immersion.

[0027] In an optional embodiment, the second vacuum cooling box is sequentially connected to a cooling tank, a quality inspection device, a traction device, and a cutting device.

[0028] Thirdly, the present invention provides an application of the crystallization-improved polybutene material described in the foregoing embodiments in polybutene pipes.

[0029] The present invention has the following beneficial effects:

[0030] This invention discloses a crystallization-improved polybutene material that can produce crystallization-improved polybutene pipes. While ensuring the performance of the pipes, it shortens the crystal transformation time, which is of great significance to production practice. Attached Figure Description

[0031] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0032] Figure 1 This is a schematic diagram of the processing apparatus for the crystallization-improved polybutene pipes described in this application.

[0033] Illustration: 1-Extruder head; 2-Vacuum chamber; 3-Heating device; 31-Heating component; 32-Guide wheel; 33-Protective cover; 4-Vacuum chamber; 5-Cooling tank; 6-Quality inspection device; 7-Traction device; 8-Cutting device. Detailed Implementation

[0034] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Where specific conditions are not specified in the embodiments, conventional conditions or conditions recommended by the manufacturer shall apply. Reagents or instruments whose manufacturers are not specified are all conventional products that can be purchased commercially.

[0035] This embodiment provides a polybutene material with improved crystallinity, the raw materials including 100 parts of polybutene and 1-10 parts of PB-based masterbatch by weight;

[0036] The raw materials of the PB-based masterbatch, by weight, include 100 parts of PB-based masterbatch carrier resin, 10-100 parts of masterbatch component resin, 6-40 parts of dispersing component and 0.5-10 parts of nucleating agent.

[0037] In this embodiment, polybutene is the main material, which can ensure the heat and pressure resistance of the pipe base; PB-based masterbatch can shorten the crystal transformation time of the pipe and improve its long-term thermal stability; masterbatch component resin is used to improve the strength, heat and pressure resistance of the product; dispersing component is used to improve the dispersion and lubrication of the masterbatch component; nucleating agent can promote the formation of crystal form and improve the rigidity and toughness balance of the product.

[0038] In the production process of PB pipes, nucleating agents are directly added for co-extrusion molding. Even if dispersing components are added, the nucleating agents will still be unevenly dispersed. The purpose of adding masterbatch to PB base material for pipe extrusion is to improve the dispersion of each component in the masterbatch in the PB base material. If the dispersion is not good, even without pressure testing, i.e., conventional hydrostatic testing, pipe rupture may still occur.

[0039] In some embodiments, the PB-based masterbatch carrier resin is polybutene with a melt index of 0.5-5 g / 10 min at 190°C and a load of 2.16 kg;

[0040] In some embodiments, the masterbatch component resin is polybutene with a melt index of 0.5-5 g / 10 min at 190°C and a load of 2.16 kg;

[0041] In some embodiments, the PB-based masterbatch carrier resin is polybutene with a melt index of 0.5-2 g / 10 min at 190°C and a load of 2.16 kg;

[0042] In some embodiments, the masterbatch component resin is polybutene with a melt index of 0.5-2 g / 10 min at 190°C and a load of 2.16 kg;

[0043] In some embodiments, under the same test conditions, the melt index of the PB-based masterbatch carrier resin is higher than that of the masterbatch component resin, which results in better coating and dispersibility of the PB-based masterbatch carrier resin, and is more conducive to the uniform dispersion of the nucleating agent.

[0044] In some embodiments, the dispersing component comprises 1-10 parts by weight of PP wax and 5-30 parts by weight of dispersant, wherein the PP wax is at least one of polypropylene wax, propylene-ethylene copolymer wax, maleic anhydride-grafted polypropylene wax, and maleic anhydride-grafted propylene-ethylene copolymer wax.

[0045] In some embodiments, the dispersing component comprises, by weight, 1-10 parts of PP wax and 5-30 parts of a dispersant, wherein the dispersant is at least one of aliphatic amide dispersants, fatty acid ester dispersants, saturated hydrocarbon dispersants, and metal soap dispersants; the aliphatic amide dispersant is ethylene bis-stearamide and / or oleamide; the fatty acid ester dispersant is pentaerythritol stearate and / or glyceryl monostearate; the saturated hydrocarbon dispersant is polyethylene wax; and the metal soap dispersant is calcium stearate and / or zinc stearate.

[0046] In some embodiments, the nucleating agent is an inorganic small molecule, inorganic salt, inorganic oxide nucleating agent such as sodium benzoate, talc, carbon black, inorganic pigment, alumina, calcium sulfate, calcium silicate, yttrium oxide, etc., sorbitol nucleating agent, aromatic substituted phosphate nucleating agent, metal phosphate nucleating agent, carboxylic acid metal salt nucleating agent, rosin nucleating agent, fused ring compound (dye, pigment) nucleating agent such as γ-quinacridone, triphenyl benzoate, etc. At least one of the following: thiazide, indigo ash, indigo gold, indigo brown, Ciba blue, organic acids and their salts such as pimelic acid and its salts, octanoic acid and its salts, glutaric acid and its salts, amide nucleating agents such as N,N'-dicyclohexyl terephthalamide, N,N'-dicyclohexyl-2,6-naphthalenediamide, and rare earth nucleating agents such as rare earth multi-component complexes or bi-complex nucleating agents formed by rare earth elements and Group IIA metals;

[0047] In some embodiments, the PB-based masterbatch carrier resin is Koattro KT MR 05, the masterbatch component resin is Akoafloor PB 4235-1, the PP wax is Licocene PP3602, the dispersant is KAO WAX EB-FF, and the nucleating agent is TMB-5. In this embodiment, both the dispersant and the PP wax contribute to the dispersion and lubrication of the masterbatch component, and they have a synergistic effect.

[0048] In practice, the types of PP wax, dispersant, and nucleating agent may differ, and their dosages may vary. Those skilled in the art can adjust the dosage as needed.

[0049] Another embodiment of this application provides a method for processing polybutene pipes with improved crystallization. After the polybutene and PB-based masterbatch described in the foregoing embodiments are mixed evenly, the polybutene pipes are obtained by extrusion. The nucleating agent is first relatively evenly distributed in the PB-based masterbatch and then mixed with the polybutene. This stepwise mixing is beneficial for the uniform mixing of the nucleating agent and the polybutene.

[0050] In an optional embodiment, the PB-based masterbatch is made by uniformly mixing the dispersing component and the nucleating agent, then uniformly mixing the PB-based masterbatch carrier resin and the masterbatch component resin, and then granulating the mixture using an extruder. This stepwise mixing facilitates the uniform distribution of the nucleating agent.

[0051] In an optional embodiment, the granulation step is performed by air-cooled die-cutting extrusion granulation, and the temperature range of the granulation step is 120-180℃.

[0052] Specifically, PP wax, dispersant, and nucleating agent are proportioned by weight and added to a small mixing device for high-speed, uniform mixing. Then, this mixture is added by weight to a large mixing device containing PB-based masterbatch carrier resin and masterbatch component resins in the specified proportions. The mixture is then transferred to the drying hopper of an extruder and extruded using an air-cooled, die-face hot-cutting process at a heating temperature range of 120-180℃ to obtain PB-based masterbatch. Next, the above components, polybutene and PB-based masterbatch, are proportioned by weight, added to a high-speed mixer for uniform mixing, and then transferred to the drying hopper of an extruder. The resulting pipes are then produced through a pipe production line at a processing temperature range of 120-180℃.

[0053] In an optional embodiment, the extruder head is sequentially connected to a first vacuum cooling box, a heating assembly 31, and a second vacuum cooling box, such as... Figure 1 As shown.

[0054] Polybutene crystallizes at a temperature between 80-110℃, beginning crystallization below its melting point. Current PB pipe manufacturing processes involve extruding molten pipes from a die, followed by cooling in a vacuum chamber 2 and cooling tank 5 to achieve the desired dimensions. However, due to the rapid production speed, the temperature drops quickly from the molten state of 180℃ to below 30℃, hindering crystal growth and maturation. By improving the manufacturing process and adding a heating device 3, a relatively longer crystal growth and maturation time is achieved within the 80-110℃ range during cooling, without affecting production speed. This significantly improves the crystallinity of the formed pipes, and the improved crystallization process helps to shorten the crystal transformation time.

[0055] In an optional embodiment, the heating assembly 31 includes two or more heating zones arranged along the material movement direction, and the temperature of the two or more heating zones is reduced from 110-120°C to 80-90°C.

[0056] The crystallization temperature of polybutene is 80-110℃. By controlling the heating temperature of heating device 3, the pipe is cooled down slowly. By controlling the cooling and crystallization processes of the pipe, the crystallization process is improved, and the crystal transformation time of the pipe is significantly shortened. In some embodiments, heating device 3 can heat through infrared radiation, electromagnetic fields, resistance, etc., and the specific structure can be as follows. Figure 1 As shown, it includes four heating components 31 and three guide wheels 32. The four heating components 31 are located in four heating zones, and the temperatures of the four heating zones are 110°C, 100°C, 90°C and 80°C respectively. In other embodiments, the number and temperature of the heating zones can also be adjusted as needed.

[0057] Preferably, the heating component 31 includes a protective cover 33, which is provided with a pipe inlet, a pipe outlet and an air outlet. A certain amount of low-temperature or high-temperature air can be introduced through the air outlet to adjust the temperature and achieve gradient cooling of the product between the heating components 31.

[0058] In an optional embodiment, the first vacuum cooling box includes an immersion cooling section and a spray cooling section. The spray cooling section is provided with two or more spray heads, and each spray head is provided with a control device that can adjust the flow rate and water temperature, so as to facilitate the adjustment of the temperature of the pipe at the outlet of the first vacuum cooling box. The specific number of spray heads can be selected by those skilled in the art as needed.

[0059] Preferably, the second vacuum cooling box uses an immersion cooling method to improve cooling efficiency.

[0060] In an optional embodiment, the second vacuum cooling box is sequentially connected to a cooling tank 5, a quality inspection device 6, a traction device 7, and a cutting device 8, wherein the quality inspection device 6 may include a laser diameter gauge, an impurity detector, etc.

[0061] Another embodiment of this application provides the application of the crystallization-improved polybutene material described in the foregoing embodiments in polybutene pipes.

[0062] The features and performance of the present invention will be further described in detail below with reference to embodiments.

[0063] Examples 1-14 provide a method for processing polybutene pipes with improved crystallinity, comprising the following steps:

[0064] Raw material preparation: The raw materials, by weight, include 100 parts of polybutene and 1-10 parts of PB-based masterbatch; the raw materials of the PB-based masterbatch, by weight, include 100 parts of PB-based masterbatch carrier resin, 10-100 parts of masterbatch component resin, 6-40 parts of dispersing component, and 0.5-10 parts of nucleating agent; the PB-based masterbatch carrier resin is Koattro KT MR 05, manufactured by LyondellBasell; the masterbatch component resin is Akoafloor PB 4235-1, manufactured by LyondellBasell; the PP wax is LicocenePP3602, manufactured by Clariant; the dispersant is KAO WAX EB-FF, manufactured by Kao; the nucleating agent is TMB-5, manufactured by Shanxi Provincial Chemical Research Institute; and the polybutene is PBTYPLEX-2050, manufactured by Ylem Technology.

[0065] PB-based masterbatch processing: The dispersing component and nucleating agent are mixed evenly, and then mixed evenly with the PB-based masterbatch carrier resin and masterbatch component resin. The mixture is then extruded and granulated using an air-cooled die-cutting process. The granulation temperature range is 120-180℃ to obtain the PB-based masterbatch.

[0066] Mixing: After the polybutene and PB-based masterbatch are mixed evenly, the polybutene pipe is obtained by extrusion. The extruder head of the extruder is connected in sequence to a first vacuum cooling box, a heating component 31, a second vacuum cooling box, a cooling tank 5, a quality inspection device 6, a traction device 7, and a cutting device 8. The heating component 31 includes four heating zones arranged along the material movement direction. The temperatures of the four heating zones are 110℃, 100℃, 90℃, and 80℃, respectively, to obtain polybutene pipe with improved crystallinity.

[0067] PB-based masterbatch was obtained by processing according to the proportions in the table below (where S represents the experimental group and D represents the control group).

[0068]

[0069] Adjust the ratio of PB-based masterbatch and polybutene according to the ratio in the table below (where S represents the experimental group and D represents the control group).

[0070]

[0071] In Examples 1-15, the raw materials for the pipes were selected from the proportions in the table above. The performance of the obtained pipes was tested, and the test results are as follows:

[0072]

[0073] In Examples 1-15, the raw materials for the pipes were selected from the proportions in the table above. The dimensions of the obtained pipes were tested, and the test results are as follows:

[0074]

[0075]

[0076] Example 15

[0077] The only difference from Example 1 is that the materials are directly mixed after preparation. The mixing step involves uniformly mixing polybutene, PB-based masterbatch carrier resin, masterbatch component resin, dispersing component and nucleating agent, and then processing them using an extruder to obtain polybutene pipes. The extruder head is sequentially connected to a first vacuum cooling box, a heating component 31, a second vacuum cooling box, a cooling tank 5, a quality inspection device 6, a traction device 7 and a cutting device 8. The heating component 31 includes four heating zones arranged along the material movement direction. The temperatures of the four heating zones are 110°C, 100°C, 90°C and 80°C, respectively, to obtain polybutene pipes with improved crystallinity.

[0078] Example 16

[0079] The only difference from Example 1 (S1+S6) is that the heating device 3 is not provided.

[0080] Example 17

[0081] The only difference from Example 12 is that the heating device 3 is not provided.

[0082] The performance of the pipes obtained in Examples 15-17 was tested, and the test results are as follows:

[0083]

[0084]

[0085] The pipe dimensions obtained in Examples 15-17 were tested, and the test results are as follows:

[0086]

[0087] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A process for the processing of a crystallinity-improved polybutene material, characterized in that, The raw materials include 100 parts of polybutene and 1-10 parts of PB-based masterbatch by weight; The raw materials of the PB-based masterbatch include 100 parts of PB-based masterbatch carrier resin, 10-100 parts of masterbatch component resin, 6-40 parts of dispersion component and 5-10 parts of nucleating agent by weight; the PB-based masterbatch carrier resin is polybutene with a melt index of 0.5-5 g / 10 min at 190℃ under a load of 2.16 kg; the masterbatch component resin is polybutene with a melt index of 0.5-5 g / 10 min at 190℃ under a load of 2.16 kg; under the same test conditions, the melt index of the PB-based masterbatch carrier resin is higher than that of the masterbatch component resin; the dispersion component includes 1-10 parts of PP wax and 5-30 parts of dispersant by weight; The processing method includes uniformly mixing the polybutene and the PB-based masterbatch, and then using an extruder to process polybutene pipes; the PB-based masterbatch is uniformly mixed with the dispersion component and the nucleating agent, and then uniformly mixed with the PB-based masterbatch carrier resin and the masterbatch component resin, and then granulated by using an extruder; The extruder head of the extruder is sequentially connected with a first vacuum cooling box, a heating assembly and a second vacuum cooling box; the heating assembly includes two or more heating zones arranged along the material moving direction, and the temperature of the two or more heating zones decreases from 110-120℃ to 80-90℃.

2. The process for processing a crystallization-improved polybutene material according to claim 1, characterized in that, The raw materials of the PB-based masterbatch meet at least one of the following ①-③; ①The PP wax is at least one of polypropylene wax, propylene-ethylene copolymer wax, maleic anhydride grafted polypropylene wax and maleic anhydride grafted propylene-ethylene copolymer wax; ②The dispersion component includes 1-10 parts of PP wax and 5-30 parts of dispersant by weight; the dispersant is at least one of aliphatic amide dispersant, fatty acid ester dispersant, saturated hydrocarbon dispersant and metal soap dispersant; the aliphatic amide dispersant is ethylene bis-stearamide and / or oleic amide; the fatty acid ester dispersant is pentaerythritol stearate and / or glycerol monostearate; the saturated hydrocarbon dispersant is polyethylene wax; the metal soap dispersant is calcium stearate and / or zinc stearate; ③The nucleating agent is at least one of inorganic salt or inorganic oxide nucleating agent, sorbitol nucleating agent, aromatic substituted phosphate nucleating agent, phosphoric acid metal salt nucleating agent, carboxylic acid metal salt nucleating agent, rosin nucleating agent, condensed ring compound nucleating agent, amide nucleating agent and rare earth nucleating agent.

3. The process for processing a crystallization-improved polybutene material according to claim 1, characterized in that, The PB-based masterbatch carrier resin is Koattro KT MR 05, the masterbatch component resin is Akoafloor PB 4235-1, the PP wax is Licocene PP 3602, the dispersant is KAO WAX EB-FF and the nucleating agent is TMB-5.

4. The process for processing a crystallization-improved polybutene pipe according to claim 1, characterized by, The granulation step is extrusion granulation by using air-cooled die face hot cutting process, and the temperature range of the granulation step is 120-180℃.

5. The process for processing a crystallization-improved polybutene pipe according to claim 1, characterized by, The heating assembly includes a protective cover, and the protective cover is provided with a pipe inlet, a pipe outlet and an air supply port.

6. The process for processing a crystallization-improved polybutene pipe according to claim 1, characterized by, The first vacuum cooling box comprises a soaking cooling section and a spraying cooling section, and the spraying cooling section is provided with two or more spraying heads, and each spraying head is provided with a control device capable of adjusting flow and water temperature.

7. The process for processing a crystallization-improved polybutene pipe according to claim 1, characterized by, The second vacuum cooling box adopts a soaking cooling mode.

8. The process for processing a crystallization-improved polybutene pipe according to claim 1, characterized by, The second vacuum cooling box is sequentially connected with a cooling tank, a quality inspection device, a traction device and a cutting device.

9. Use of a polybutene material with improved crystallization obtained by the process according to any one of claims 1 to 8 in polybutene pipes.

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