Method for producing functionalized polyolefins

Abstract

To enable a polyolefin having a double bond to be continuously produced, thereby making it possible to provide the double bond-bearing polyolefin at low cost and stably; to introduce an epoxy group, a hydroxy group, or a carboxyl group to the polyolefin for denaturation, allowing the polyolefin to be used as the raw material for adhesives, coatings, or additives; and, thus, to improve poor affinity with other materials, such as adhesiveness and coatability, which is a weak point in the polyolefin.SOLUTION: A method for producing a pyrolytic polyolefin having a double bond includes the steps of: preparing a base polyolefin; and continuously pyrolyzing the prepared base polyolefin at a pyrolytic temperature of 300°C or higher.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a method for producing a pyrolytic polyolefin having double bonds produced from a raw material polyolefin. [Background technology]

[0002] Polyolefins such as polypropylene have excellent properties such as excellent oil resistance, chemical resistance, and reduced environmental impact. Taking advantage of these properties of polyolefins, their application to various uses is being considered. In applying polyolefins to various uses, polyolefins may be used to produce molded articles in desired shapes such as films.

[0003] On the other hand, polyolefins are non-polar polymers and it is difficult to introduce functional groups into them, so they have poor interaction with polar substances and are difficult to mix with polymers having polar groups. Therefore, polyolefins have a limited range of application, such as problems of inability to obtain paintability and adhesiveness, and problems of inability to obtain sufficient strength in molded products. Therefore, in order to expand the range of application of polyolefins, methods of introducing polar groups or functional groups into polyolefins have been attempted.

[0004] As a method for introducing polar groups or functional groups into polyolefins, particularly polypropylene-based resins, the present inventors have investigated precision pyrolysis, which can efficiently produce polypropylene-based resins containing double bonds at both ends (Non-Patent Documents 1 and 2).

[0005] Furthermore, as a method for synthesizing polyolefins having functional groups at both ends, a synthesis method based on olefin polymerization rather than on polyolefin decomposition has also been reported (Patent Document 1).

[0006] Patent Document 2 also describes a method for producing polyolefins with terminal double bonds by pyrolyzing polyolefins in a Kolben. Patent Document 2 specifically discloses that the number of double bonds per molecule is about 1.5, since there are 4.2 terminal double bonds per 1000 carbons when the reaction time is 1.5 hours and the number average molecular weight is 5000. The above disclosure statistically estimates that about 56 mol% of polyolefins with double bonds at both ends are contained.

[0007] Patent Document 3 discloses continuous thermal degradation (pyrolysis) of polyolefin in a tubular reactor. The low molecular weight polyolefin obtained in Patent Document 3 has a number average molecular weight of 500 to 10,000, but the number of double bonds is not specified. Patent Document 3 also discloses that a long reaction time of 0.5 to 10 hours is required.

[0008] In producing polyolefins having functional groups such as double bonds at both ends, olefin polymerization has not been put to practical use due to problems such as the use of a dedicated catalyst and the inability to precisely accommodate various commercially available polyolefins. On the other hand, in producing polyolefins having functional groups such as double bonds at both ends, a production method using pyrolysis has the advantage that double bond polyolefins can be synthesized at low cost by using inexpensive commercially available polyolefins, and that it is easy to accommodate various commercially available polyolefins. [Prior art documents] [Non-patent literature]

[0009] [Non-Patent Document 1] Macromolecules, 28, 7973(1995) [Non-Patent Document 2] Journal of Analytical and Applied Pyrolysis, 80, 312-318(2007) [Patent documents]

[0010] [Patent Document 1] JP 2005-97588 A [Patent Document 2] Japanese Patent Application Publication No. 3-91547 [Patent Document 3] Japanese Patent Application Publication No. 3-62804 Summary of the Invention [Problem to be solved by the invention]

[0011] In view of the above circumstances, an object of the present invention is to provide a method for producing pyrolytic polyolefins having double bonds, which can efficiently produce polyolefins having double bonds using a pyrolysis method, in order to expand the range of application of polyolefins. [Means for solving the problem]

[0012] The gist of the configuration of the present invention is as follows. [1] preparing a raw material polyolefin; The method for producing a pyrolytic polyolefin having double bonds includes a step of continuously pyrolyzing the prepared raw material polyolefin at a pyrolysis temperature of 300° C. or higher. [2] The method according to [1], wherein the pyrolysis temperature is 300°C or higher and 500°C or lower. [3] The method according to [1] or [2], wherein the thermal decomposition time is from 30 seconds to 1200 seconds. [4] The method according to any one of [1] to [3], wherein the starting polyolefin is a starting polyolefin having no tertiary carbon or quaternary carbon in its side chain. [5] The method according to [4], wherein the starting polyolefin having no tertiary or quaternary carbon in its side chain is a polyolefin having a chain olefin monomer having 2 to 10 carbon atoms as a constituent unit. [6] The method according to [4] or [5], wherein the raw material polyolefin having no tertiary or quaternary carbon in its side chain is a polymer containing ethylene, propylene and / or 1-butene as monomer constituent units, and the pyrolytic polyolefin having double bonds is a pyrolytic polyolefin having double bonds only at the terminals. [7] The method according to any one of [1] to [3], wherein the starting polyolefin is a starting polyolefin having a tertiary carbon in a side chain. [8] The method according to [7], wherein the starting polyolefin having a tertiary carbon in its side chain is a polyolefin having a chain olefin monomer having 5 to 10 carbon atoms as a constituent unit, or a cycloolefin polymer. [9] The method according to [7] or [8], wherein the starting polyolefin having a tertiary carbon in its side chain is a polymer containing 4-methylpentene and / or cycloolefin as a monomer unit, and the pyrolytic polyolefin having a double bond is a pyrolytic polyolefin having double bonds at the terminal and inside the molecular chain.

[0013] The "continuous pyrolysis" in [1] above includes precision pyrolysis. Precision pyrolysis refers to the precision pyrolysis (highly controlled pyrolysis) developed by the present inventors (see Macromolecules, 28, 7973 (1995)). Thus, the pyrolysis polyolefin having double bonds obtained by the production method of the present invention is a pyrolysis product of the raw polyolefin, which can be obtained by subjecting the raw polyolefin to a pyrolysis treatment using the precision pyrolysis (highly controlled pyrolysis). In addition, the double bond of the "pyrolysis polyolefin having double bonds" includes an ethylenic double bond. Effect of the Invention

[0014] According to the embodiment of the method for producing pyrolytic polyolefins having double bonds of the present invention, pyrolytic polyolefins having double bonds with an improved number of double bonds per molecule can be efficiently produced by continuously pyrolyzing raw polyolefins at a pyrolysis temperature of 300° C. or higher. In addition, since the number average molecular weight of pyrolytic polyolefins having double bonds obtained by the production method of the present invention is smaller than the number average molecular weight of the raw polyolefins, the thermally melted pyrolytic polyolefins having double bonds have high fluidity. Therefore, pyrolytic polyolefins having double bonds have excellent moldability during injection molding and the like.

[0015] The pyrolyzed polyolefin having double bonds obtained by the production method of the present invention maintains the properties of the raw material polyolefin, such as the melting point and solvent solubility, and therefore, depending on the properties of the raw material polyolefin, various pyrolyzed polyolefins having desired properties, such as pyrolyzed polyolefins with excellent heat resistance or pyrolyzed polyolefins with excellent solubility in solvents, can be produced.

[0016] The pyrolyzed polyolefin having double bonds obtained by the production method of the present invention has excellent chemical reactivity, and by utilizing the reactivity of the double bonds, it is possible to convert them into various functional groups. For example, by converting the double bonds of pyrolyzed polyolefins into epoxy groups, hydroxyl groups, carboxyl groups, etc., they can be used as additives for paints, adhesives, resins, etc.

[0017] Furthermore, according to the embodiment of the method for producing pyrolytic polyolefins having double bonds of the present invention, the pyrolysis is continuous by the precision pyrolysis method, and therefore the yield and productivity of pyrolytic polyolefins having double bonds are improved.

[0018] According to an embodiment of the method for producing pyrolytic polyolefins having double bonds of the present invention, the pyrolysis temperature is 300°C or higher and 500°C or lower, so that pyrolytic polyolefins having double bonds with a more reliably improved number of double bonds per molecule can be produced more efficiently while preventing thermal degradation of the pyrolytic polyolefins produced.

[0019] According to an embodiment of the method for producing pyrolytic polyolefins having double bonds of the present invention, the pyrolysis time is from 30 seconds to 1200 seconds, whereby pyrolytic polyolefins having double bonds with a more reliably improved number of double bonds per molecule can be produced more efficiently while preventing the pyrolytic polyolefins produced from being reduced in molecular weight. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0020] The method for producing a pyrolytic polyolefin having a double bond of the present invention is described in detail below. The method for producing a pyrolytic polyolefin having a double bond of the present invention includes a step of preparing a raw material polyolefin and a step of continuously pyrolyzing the prepared raw material polyolefin at a pyrolysis temperature of 300° C. or higher.

[0021] <Raw polyolefin> The raw polyolefin may be, for example, a raw polyolefin having no tertiary or quaternary carbon in the side chain. When the raw polyolefin has a chemical structure having no tertiary or quaternary carbon in the side chain, the pyrolytic polyolefin obtained by the production method of the present invention has double bonds derived from pyrolysis at both ends or one end, and does not have double bonds derived from pyrolysis in the molecular chain. Therefore, the pyrolytic polyolefin having double bonds may be, for example, a pyrolytic polyolefin having double bonds only at the ends.

[0022] Examples of raw polyolefins having no tertiary or quaternary carbon in the side chain include polymers of linear olefins. More specifically, examples of raw polyolefins having no tertiary or quaternary carbon in the side chain include polyolefins having a structural unit of a linear olefin monomer having 2 to 10 carbon atoms, preferably a linear olefin monomer having 3 to 5 carbon atoms. Examples of the linear olefin monomer having 2 to 10 carbon atoms include ethylene, propylene, 1-butene, etc. The linear olefin monomer constituting the raw polyolefin may be one type, or two or more types may be used in combination. Examples of raw polyolefins having one type of linear olefin monomer include polyethylene, polypropylene, poly(1-butene), etc. When two or more types of linear olefin monomers are used in combination, the raw polyolefin is a copolymer.

[0023] In addition, the raw polyolefin may, for example, be a raw polyolefin having a tertiary carbon in the side chain. When the raw polyolefin has a chemical structure having a tertiary carbon in the side chain, the pyrolytic polyolefin obtained by the production method of the present invention has double bonds derived from pyrolysis at both ends or one end, and also has double bonds derived from pyrolysis in the molecular chain corresponding to the position of the tertiary carbon in the side chain. Therefore, the pyrolytic polyolefin having double bonds may, for example, be a pyrolytic polyolefin having double bonds at the end and in the molecular chain.

[0024] Examples of the raw material polyolefin having a tertiary carbon in the side chain include a polymer of a chain olefin and a polymer of a cyclic olefin (cycloolefin). More specifically, in the case of a polymer of a chain olefin, examples of the raw material polyolefin having a tertiary carbon in the side chain include a polyolefin having a chain olefin monomer having 5 to 10 carbon atoms, preferably a chain olefin monomer having 6 to 8 carbon atoms, as a constituent unit. Examples of the chain olefin monomer having 5 to 10 carbon atoms include 4-methylpentene. The chain olefin monomer constituting the raw material polyolefin may be one type, or two or more types may be used in combination. Examples of the raw material polyolefin having one type of chain olefin monomer include poly(4-methylpentene).

[0025] In addition, the raw material polyolefin having a tertiary carbon in the side chain may be, for example, a polymer of an olefin having a cyclopentane skeleton in the case of a polymer of a cyclic olefin (cycloolefin). The polymer of a cyclic olefin (cycloolefin) may be a polymer of a cyclic olefin (cycloolefin) or a copolymer of a cyclic olefin (cycloolefin) and the above-mentioned chain olefin.

[0026] <Process for continuous pyrolysis of raw polyolefin> As a method for continuously pyrolyzing raw polyolefin, the raw polyolefin is fed to a pyrolysis apparatus for precision pyrolysis, and pyrolyzed by a precision pyrolysis method. The pyrolysis apparatus for precision pyrolysis is not particularly limited, but includes a batch type apparatus and a continuous type apparatus. As an example of a batch type apparatus, the apparatus disclosed in Journal of Polymer Science: Polymer Chemistry Edition, 21, 703 (1983) can be used. More specifically, the raw polyolefin (e.g., polypropylene) is fed into a reaction vessel of a pyrolysis apparatus made of Pyrex (registered trademark) glass, and the molten polymer phase is vigorously bubbled with nitrogen gas under reduced pressure, and the volatile products are extracted, thereby causing a pyrolysis reaction at a predetermined temperature for a predetermined time while suppressing secondary reactions. After the pyrolysis reaction is completed, the residue in the reaction vessel is dissolved in hot xylene, filtered while hot, and then reprecipitated with alcohol for purification. The reprecipitate is collected by filtration and vacuum dried to obtain a polyolefin having double bonds (e.g., polypropylene containing double bonds at both ends).

[0027] The continuous type apparatus has a structure in which raw polyolefin is continuously fed into the reaction vessel, and the fed raw polyolefin is sequentially moved in the reaction vessel toward the outlet of the reaction vessel while being pyrolyzed. The reaction vessel is equipped with a preheating zone for melting the fed raw polyolefin, a high-temperature heating zone for pyrolyzing the raw polyolefin, and a preliminary cooling zone for facilitating solidification of the raw polyolefin, and each zone may be independent or integrated. As the pyrolysis apparatus for precision pyrolysis, a continuous type apparatus is preferred from the viewpoints of improving the yield of pyrolyzed polyolefin having double bonds and productivity.

[0028] The method for heating the high-temperature heating zone of the pyrolysis device for precision pyrolysis is not particularly limited, and examples thereof include electric heaters and flames. Among these, electric heaters are preferred from the viewpoint of temperature control and safe operation. In addition, it is also possible to effectively utilize the shear heat generated when stirring the raw polyolefin in the pyrolysis device for precision pyrolysis.

[0029] In the pyrolysis device for precision pyrolysis, the raw polyolefin is preferably stirred in order to remove the generated gas and to proceed pyrolysis uniformly. The stirring speed of the raw polyolefin varies depending on the shape of the pyrolysis device for precision pyrolysis and the shape of the stirring blade, but is preferably 50 rpm or more and 5000 rpm or less in order to proceed pyrolysis more uniformly while reliably removing the generated gas. In the high rotation range exceeding 1000 rpm, shear heat is generated, but it is desirable to effectively utilize the generated heat to heat efficiently.

[0030] The thermal decomposition conditions are adjusted taking into consideration the number average molecular weight of the raw polyolefin and the number average molecular weight of the thermally decomposed polypropylene having double bonds. In the present invention, the thermal decomposition temperature of the raw polyolefin is 300°C or higher. By having the thermal decomposition temperature of the raw polyolefin be 300°C or higher, a thermally decomposed polyolefin having double bonds with an improved number of double bonds per molecule can be efficiently produced. The thermal decomposition temperature of the raw polyolefin is not particularly limited as long as it is 300°C or higher, but for example, from the viewpoint of the balance between the promotion of the thermal decomposition reaction and the prevention of thermal degradation of the thermal decomposition product, the range of 300°C to 500°C is preferable, the range of 320°C to 480°C is more preferable, and the range of 370°C to 430°C is particularly preferable.

[0031] The thermal decomposition time of the raw material polyolefin is preferably from 30 to 1,200 seconds, particularly preferably from 50 to 900 seconds, in order to reliably obtain a thermal decomposition product having a double bond while preventing a decrease in strength of the molded product due to the degradation of the molecular weight of the thermal decomposition product.

[0032] In a continuous precision pyrolysis pyrolysis apparatus, for example, the pyrolysis time of the raw polyolefin can be adjusted by adjusting the feed rate per unit time and the extrusion speed of the raw polyolefin.

[0033] <Characteristics of polyolefin> The number average molecular weight (Mn) of the raw material polyolefin is not particularly limited, but since the number of double bonds in the pyrolyzed polyolefin decreases when the number of molecular cleavage due to pyrolysis is small, it is preferable that the raw material polyolefin has a molecular weight of a certain level or more. The number average molecular weight (Mn) of the raw material polyolefin is preferably 20,000 or more and 1,500,000 or less, for example, in order to ensure a sufficient number of double bonds. It is also possible to reduce the number of double bonds in the pyrolyzed polyolefin by lowering the number average molecular weight (Mn) of the raw material polyolefin. In addition, when using a polyolefin that is commercially available as the raw material polyolefin, it is preferable to use a polyolefin with the highest number average molecular weight from the viewpoint of cost.

[0034] The number average molecular weight of the pyrolyzed polyolefin having double bonds may vary depending on the number average molecular weight of the raw material polyolefin, but is preferably from 10,000 to 50,000 in terms of obtaining strength of molded products while reliably imparting excellent moldability during injection molding, etc. On the other hand, when the pyrolyzed polyolefin having double bonds is used as a raw material for paints or adhesives, the number average molecular weight is preferably from 1,000 to 20,000 in terms of reactivity and solubility.

[0035] The value of weight average molecular weight (Mw) / number average molecular weight (Mn), which indicates the degree of dispersion of the molecular weight distribution of the pyrolytic polyolefin having double bonds, is not particularly limited, but is preferably 1.0 to 3.5, particularly preferably 1.5 to 3.0. In this specification, the number average molecular weight (Mn) and the weight average molecular weight (Mw) refer to the molecular weight measured by gel permeation chromatography (GPC).

[0036] In the method for producing a pyrolytic polyolefin having a double bond of the present invention, a pyrolytic polyolefin having a double bond and a chemical structure that maintains the stereoregularity and monomer composition of the raw polyolefin can be obtained. For example, when the raw polyolefin is a polymer of a chain olefin, a polymer of a chain olefin having a double bond can be obtained as a pyrolytic product, and when the raw polyolefin is a polymer of a cyclic olefin (cycloolefin), a polymer of a cyclic olefin (cycloolefin) having a double bond can be obtained as a pyrolytic product. More specifically, when the raw polyolefin is polyethylene, a polyethylene having a double bond can be obtained as a pyrolytic product; when the raw polyolefin is polypropylene, a polypropylene having double bonds at both ends can be obtained as a pyrolytic product; when the raw polyolefin is poly(1-butene), a poly(1-butene) having double bonds at both ends can be obtained as a pyrolytic product; and when the raw polyolefin is poly(4-methylpentene), a poly(4-methylpentene) having double bonds at both ends and further having a double bond in the molecular chain can be obtained as a pyrolytic product.

[0037] <Molding of pyrolyzed polyolefins containing double bonds> The pyrolytic polyolefin having double bonds obtained by the production method of the present invention can be used to obtain molded articles in an appropriate shape, such as a film, a sheet, a block, a flake, a powder, etc. Examples of methods for molding molded articles using pyrolytic polyolefin having double bonds include injection molding. EXAMPLES

[0038] Next, examples of the present invention will be described. However, the present invention is not limited to these examples as long as they do not depart from the spirit of the present invention.

[0039] Example 1 As the raw polyolefin, isotactic polypropylene (Novatec EA9, manufactured by Japan Polypropylene Corporation, Mn = 92000, Mw / Mn = 5.5) was prepared. This raw polypropylene was subjected to precision pyrolysis treatment in a continuous pyrolysis apparatus for precision pyrolysis to obtain isotactic polypropylene having double bonds at both ends as a pyrolysis product. The pyrolysis temperature was 430 ° C., and the pyrolysis time was 70 seconds, 150 seconds, and 210 seconds. When the pyrolysis time was 70 seconds, the supply amount of raw isotactic polypropylene was 3 kg / hr, and the number average molecular weight of pyrolysis product 1-1 was 20000, when the pyrolysis time was 150 seconds, the supply amount of raw isotactic polypropylene was 1 kg / hr, and the number average molecular weight of pyrolysis product 1-2 was 10000, and when the pyrolysis time was 210 seconds, the supply amount of raw isotactic polypropylene was 0.5 kg / hr, and the number average molecular weight of pyrolysis product 1-3 was 6600.

[0040] The number average molecular weights of the pyrolysis products 1-1 to 1-3 were measured by high-temperature gel permeation chromatography (high-temperature GPC). Specifically, the instrument used was "HLC-8321GPC / HT" manufactured by Tosoh Corporation, and the column used was "TSKgel GMHHR-H(20)HT" manufactured by Tosoh Corporation. In the measurement method, trichlorobenzene was used as the mobile phase as a solvent in which the pyrolysis products 1-1 to 1-3 are dissolved, and polystyrene (PS) was used as the standard substance. A differential refractometer was used as the detector.

[0041] The average number of double bonds per molecule of the pyrolysis products was measured by a nuclear magnetic resonance spectroscopy (NMR) device. The measuring device was 1HNMR or 13CNMR. In the case of 1HNMR, it was estimated from the intensity ratio of the double bonds to the main chain and the molecular weight obtained by GPC, etc. In the case of 13CNMR, it was estimated from the intensity ratio of the double bond end to the saturated end. The number of terminal double bonds per molecule of pyrolysis products 1-1 to 1-3 was 1.8. In addition, with infrared spectroscopy, a calibration curve was created in advance from the intensity ratio of the main chain and double bonds, and the number of double bonds can be estimated by clarifying the molecular weight of the pyrolysis products.

[0042] Evaluation items (1) Formability Each of the pyrolysis products 1-1 to 1-3 obtained as described above was compression molded at 200°C (compression molding machine manufactured by Toyo Seiki Co., Ltd., model number MP-WCH) to produce a film-like molded product having a length of 40 mm, a width of 40 mm, and a thickness of 2 mm.

[0043] The condition of each molded article obtained as described above was visually observed and evaluated according to the following three-level scale. ◯: No defects such as cracks or fissures were found in the molded product. △: Some cracks were observed in the molded product. ×: The molded product is cracked.

[0044] (2) Heat resistance (melting point) The melting points of the pyrolysis products 1-1 to 1-3 were determined by differential scanning calorimetry (DSC). The melting points were measured in the temperature range of 0°C to 230°C using a DSC6100 manufactured by Seiko Instruments Inc.

[0045] (3) Chemical reactivity To assess the chemical reactivity of the double bond, the following reaction was performed. 80 mL of tetrahydrofuran was added to 10 g of isotactic polypropylene having double bonds at the ends obtained by thermal decomposition, 20 mL of borane-tetrahydrofuran complex / tetrahydrofuran solution (1M) was added, and the mixture was stirred at 60°C for 5 hours. Then, 10 mL of 5N NaOH aqueous solution was added, followed by 10 mL of 30% by mass hydrogen peroxide solution, and the mixture was stirred at 60°C for 5 hours. After the reaction, whether or not the double bonds were converted to hydroxyl groups by reprecipitation purification was measured by infrared spectroscopy or 1H-NMR, and evaluated as follows. ○: Reactive ×: No reactivity

[0046] Example 2 As the raw material polyolefin, random polypropylene A (manufactured by Japan Polypropylene Corporation, Novatec EG8B, Mw = 71000, Mw / Mn = 6.2) was prepared. This raw material random polypropylene A was subjected to precision pyrolysis treatment in a continuous pyrolysis apparatus for precision pyrolysis to obtain random polypropylene A having double bonds at both ends as a pyrolysis product. The pyrolysis temperature was 430 ° C., and the pyrolysis time was 70 seconds, 150 seconds, and 210 seconds. When the pyrolysis time was 70 seconds, the supply amount of raw material random polypropylene A was 3 Kg / hr, and the number average molecular weight of pyrolysis product 2-1 was 18000, when the pyrolysis time was 150 seconds, the supply amount of raw material random polypropylene A was 1 Kg / hr, and the number average molecular weight of pyrolysis product 2-2 was 8500, and when the pyrolysis time was 210 seconds, the supply amount of raw material random polypropylene A was 0.5 Kg / hr, and the number average molecular weight of pyrolysis product 2-3 was 5300. The number average molecular weights of the pyrolysis products 2-1 to 2-3 were measured in the same manner as in Example 1. The average number of terminal double bonds per molecule was measured in the same manner as in Example 1 and was found to be 1.8.

[0047] Example 3 Random polypropylene B (manufactured by Mitsui Chemicals, Inc., Toughmer, Mn = 91000, Mw / Mn = 2.4) was prepared as a raw material polyolefin. This raw material random polypropylene B was subjected to precision pyrolysis treatment in a continuous pyrolysis apparatus for precision pyrolysis to obtain a pyrolysis product, random polypropylene B having double bonds at both ends. The pyrolysis temperature was 430 ° C., and the pyrolysis time was 70 seconds, 150 seconds, and 210 seconds. When the pyrolysis time was 70 seconds, the supply amount of raw material random polypropylene B was 3 Kg / hr, and the number average molecular weight of pyrolysis product 3-1 was 37000. When the pyrolysis time was 150 seconds, the supply amount of raw material random polypropylene B was 1 Kg / hr, and the number average molecular weight of pyrolysis product 3-2 was 8900. When the pyrolysis time was 210 seconds, the supply amount of raw material random polypropylene B was 0.5 Kg / hr, and the number average molecular weight of pyrolysis product 3-3 was 5400. The number average molecular weights of the pyrolysis products 3-1 to 3-3 were measured in the same manner as in Example 1. The average number of terminal double bonds per molecule was measured in the same manner as in Example 1 and was found to be 1.8.

[0048] Example 4 As the raw material polyolefin, a cycloolefin polymer (ZEON Corporation, Zeonor, Mw=33000, Mw / Mn=1.8) was prepared. This raw material cycloolefin polymer was subjected to precision pyrolysis in a continuous pyrolysis apparatus for precision pyrolysis to obtain a pyrolysis product, a cycloolefin polymer having a double bond. The pyrolysis temperature was 430° C., and the pyrolysis time was 70 seconds, 150 seconds, and 210 seconds. When the pyrolysis time was 70 seconds, the supply amount of the raw material cycloolefin polymer was 3 kg / hr, and the number average molecular weight of the pyrolysis product 4-1 was 25000. When the pyrolysis time was 150 seconds, the supply amount of the raw material cycloolefin polymer was 1 kg / hr, and the number average molecular weight of the pyrolysis product 4-2 was 15000. When the pyrolysis time was 210 seconds, the supply amount of the raw material cycloolefin polymer was 0.5 kg / hr, and the number average molecular weight of the pyrolysis product 4-3 was 9500. The average number of double bonds per molecule was measured in the same manner as in Example 1 and was found to be 1.8.

[0049] Example 5 Cycloolefin copolymer (manufactured by Mitsui Chemicals, Inc., APEL, Mn=48000, Mw / Mn=2.1) was prepared as the raw material polyolefin. This raw material cycloolefin copolymer was subjected to precision pyrolysis treatment in a continuous pyrolysis apparatus for precision pyrolysis to obtain a pyrolysis product, a cycloolefin copolymer having a double bond. The pyrolysis temperature was 430°C, and the pyrolysis time was 70 seconds, 150 seconds, and 210 seconds. When the pyrolysis time was 70 seconds, the supply amount of the raw material cycloolefin copolymer was 3Kg / hr, and the number average molecular weight of the pyrolysis product 5-1 was 19000. When the pyrolysis time was 150 seconds, the supply amount of the raw material cycloolefin copolymer was 1Kg / hr, and the number average molecular weight of the pyrolysis product 5-2 was 9800. When the pyrolysis time was 210 seconds, the supply amount of the raw material cycloolefin copolymer was 0.5Kg / hr, and the number average molecular weight of the pyrolysis product 5-3 was 5500. The average number of double bonds per molecule was measured in the same manner as in Example 1 and was found to be 1.8.

[0050] Example 6 Poly(4-methylpentene) (Mitsui Chemicals, Inc., TPX, Mn=73000, Mw / Mn=7.1) was prepared as the raw polyolefin. This raw poly(4-methylpentene) was subjected to precision pyrolysis in a continuous pyrolysis apparatus for precision pyrolysis to obtain poly(4-methylpentene) having double bonds at the terminals and inside the molecular chain as the pyrolysis product. The pyrolysis temperature was 430°C, and the pyrolysis time was 70 seconds, 150 seconds, and 210 seconds. When the pyrolysis time was 70 seconds, the supply amount of the raw material poly(4-methylpentene) was 3 kg / hr, and the number average molecular weight of the pyrolysis product 6-1 was 19000. When the pyrolysis time was 150 seconds, the supply amount of the raw material poly(4-methylpentene) was 1 kg / hr, and the number average molecular weight of the pyrolysis product 6-2 was 11000. When the pyrolysis time was 210 seconds, the supply amount of the raw material poly(4-methylpentene) was 0.5 kg / hr, and the number average molecular weight of the pyrolysis product 6-3 was 6800. The number average molecular weights of the pyrolysis products 6-1 to 6-3 were measured in the same manner as in Example 1. The average number of double bonds per molecule was measured in the same manner as in Example 1 and was 1.8.

[0051] Example 7 Poly(1-butene) (Mitsui Chemicals, Inc., Mn=210000, Mw / Mn=3.8) was prepared as the raw polyolefin. This raw poly(1-butene) was subjected to precision pyrolysis in a continuous pyrolysis apparatus for precision pyrolysis to obtain poly(1-butene) having double bonds at both ends as the pyrolysis product. The pyrolysis temperature was 430°C, and the pyrolysis time was 70 seconds, 150 seconds, and 210 seconds. When the pyrolysis time was 70 seconds, the supply amount of raw material poly(1-butene) was 3 kg / hr, and the number average molecular weight of pyrolysis product 7-1 was 19000. When the pyrolysis time was 150 seconds, the supply amount of raw material poly(1-butene) was 1 kg / hr, and the number average molecular weight of pyrolysis product 7-2 was 11000. When the pyrolysis time was 210 seconds, the supply amount of raw material poly(1-butene) was 0.5 kg / hr, and the number average molecular weight of pyrolysis product 7-3 was 6800. The number average molecular weights of pyrolysis products 7-1 to 7-3 were measured in the same manner as in Example 1. The average number of terminal double bonds per molecule was measured in the same manner as in Example 1 and was 1.8.

[0052] Example 8 As the raw material polyolefin, polyethylene (Prime Polymer, Hi-Zex, Mn=210000, Mw / Mn=3.8) was prepared. This raw material polyethylene was subjected to precision pyrolysis in a continuous pyrolysis apparatus for precision pyrolysis to obtain a polyethylene having a double bond as a pyrolysis product. The pyrolysis temperature was 430° C., and the pyrolysis time was 70 seconds, 150 seconds, and 210 seconds. When the pyrolysis time was 70 seconds, the supply amount of the raw material polyethylene was 3 kg / hr, and the number average molecular weight of the pyrolysis product 8-1 was 15000. When the pyrolysis time was 150 seconds, the supply amount of the raw material polyethylene was 1 kg / hr, and the number average molecular weight of the pyrolysis product 8-2 was 8200. When the pyrolysis time was 210 seconds, the supply amount of the raw material polyethylene was 0.5 kg / hr, and the number average molecular weight of the pyrolysis product 8-3 was 6100. The number average molecular weights of the pyrolysis products 8-1 to 8-3 were measured in the same manner as in Example 1. The average number of double bonds per molecule was measured in the same manner as in Example 1 and was found to be 1.3.

[0053] Example 9 Waste polypropylene (mainly polypropylene derived from home appliances, Mn=53000, Mw / Mn=5.4) was prepared as raw polyolefin. This raw waste polypropylene was subjected to precision pyrolysis treatment in a continuous pyrolysis device for precision pyrolysis to obtain waste polypropylene having double bonds as a pyrolysis product. The pyrolysis temperature was 430°C, and the pyrolysis time was 70 seconds, 150 seconds, and 210 seconds. When the pyrolysis time was 70 seconds, the supply amount of raw waste polypropylene was 3Kg / hr, and the number average molecular weight of pyrolysis product 9-1 was 13000. When the pyrolysis time was 150 seconds, the supply amount of raw waste polypropylene was 1Kg / hr, and the number average molecular weight of pyrolysis product 9-2 was 8100. When the pyrolysis time was 210 seconds, the supply amount of raw waste polypropylene was 0.5Kg / hr, and the number average molecular weight of pyrolysis product 9-3 was 3900. The number average molecular weights of pyrolysis products 9-1 to 9-3 were measured in the same manner as in Example 1. The average number of double bonds per molecule was measured in the same manner as in Example 1 and was found to be 1.6.

[0054] Example 10 Waste polyethylene (mainly polyethylene derived from packaging materials, Mn=25000, Mw / Mn=5.4) was prepared as the raw material polyolefin. This raw material waste polyethylene was subjected to precision pyrolysis treatment in a continuous pyrolysis device for precision pyrolysis to obtain waste polyethylene having double bonds as a pyrolysis product. The pyrolysis temperature was 430°C, and the pyrolysis time was 70 seconds, 150 seconds, and 210 seconds. When the pyrolysis time was 70 seconds, the supply amount of raw material waste polyethylene was 3Kg / hr, and the number average molecular weight of pyrolysis product 10-1 was 11000. When the pyrolysis time was 150 seconds, the supply amount of raw material waste polyethylene was 1Kg / hr, and the number average molecular weight of pyrolysis product 10-2 was 7300. When the pyrolysis time was 210 seconds, the supply amount of raw material waste polyethylene was 0.5Kg / hr, and the number average molecular weight of pyrolysis product 10-3 was 4100. The number average molecular weights of pyrolysis products 10-1 to 10-3 were measured in the same manner as in Example 1. The average number of double bonds per molecule was measured in the same manner as in Example 1 and was found to be 1.2.

[0055] Comparative Example 1 As the raw material polyolefin, isotactic polypropylene (Novatec EA9, manufactured by Japan Polypropylene Corporation, Mn=92000, Mw / Mn=5.5) was prepared. This raw material isotactic polypropylene was subjected to precision pyrolysis treatment in a continuous pyrolysis apparatus for precision pyrolysis to obtain isotactic polypropylene having double bonds at both ends as a pyrolysis product. The pyrolysis temperature was 280°C, and the pyrolysis time was 70 seconds. When the pyrolysis time was 70 seconds, the supply amount of the raw material random polypropylene was 3Kg / hr, and the number average molecular weight of the pyrolysis product C1-1 was 87000. The number average molecular weight of the pyrolysis product C1-1 was measured in the same manner as in Example 1. The average number of terminal double bonds per molecule was measured in the same manner as in Example 1, but the concentration of double bonds was low and could not be detected.

[0056] Comparative Example 2 The number average molecular weight of a commercially available pyrolyzed polypropylene (Hiwax, NP055, manufactured by Mitsui Chemicals, Inc.) was measured in the same manner as in Example 1 and was found to be 6800. The average number of terminal double bonds per molecule was measured in the same manner as in Example 1 and was found to be 1.3.

[0057] Comparative Example 3 The number average molecular weight of a commercially available pyrolyzed polypropylene (Viscol, 660-P, manufactured by Sanyo Chemical Co., Ltd.) was measured in the same manner as in Example 1 and was found to be 7400. The average number of terminal double bonds per molecule was measured in the same manner as in Example 1 and was found to be 1.3.

[0058] For the above-mentioned Examples 2 to 10 and Comparative Examples 1 to 3, the moldability, heat resistance (melting point), and chemical reactivity were evaluated in the same manner as in Example 1.

[0059] The evaluation results of Examples 1 to 10 and Comparative Examples 1 to 3 are shown in the following Tables 1 and 2. The weight average molecular weights in Tables 1 and 2 were measured by gel permeation chromatography (GPC) in the same manner as the number average molecular weight.

[0060] [Table 1]

[0061] [Table 2]

[0062] From Table 1 above, in Examples 1 to 10 in which the raw material polyolefin was continuously pyrolyzed at 430°C to produce pyrolytic polyolefin having double bonds, a film that was prevented from defects such as cracks and cracks could be molded from the pyrolytic polyolefin regardless of the pyrolysis time of 70 seconds to 210 seconds, and the moldability was excellent. In addition, in Examples 1 to 10, the melting point drop compared to the raw material was only 15°C or less at a pyrolysis time of 70 seconds, and it was found that the heat resistance was also excellent. In addition, the pyrolytic polyolefin obtained in Examples 1 to 10 was also excellent in chemical reactivity, and it was found that it could be used as a raw material for adhesives, paints, additives, etc. by modifying the pyrolytic polyolefin by introducing epoxy groups, hydroxyl groups, carboxyl groups, etc.

[0063] On the other hand, from Table 2 above, in Comparative Example 1, in which a pyrolytic polyolefin having double bonds was produced by continuously pyrolyzing a raw material polyolefin at temperatures less than 280°C and 300°C, moldability and heat resistance were obtained, but the number of double bonds was small, and chemical reactivity was not obtained. Therefore, in Comparative Example 1, it was found that it is difficult to use the pyrolytic polyolefin as a raw material for adhesives, paints, additives, etc. by modifying it by introducing epoxy groups, hydroxyl groups, carboxyl groups, etc. into the pyrolytic polyolefin. In addition, in Comparative Examples 2 and 3, in which a commercially available pyrolytic polypropylene was used, heat resistance and chemical reactivity were obtained, but moldability was not obtained. [Industrial Applicability]

[0064] The present invention makes it possible to continuously produce polyolefins having double bonds, and thus to stably provide polyolefins having double bonds at low cost. Therefore, by modifying pyrolyzed polyolefins by introducing epoxy groups, hydroxyl groups, carboxyl groups, etc., the polyolefins can be used as raw materials for adhesives, paints, additives, etc. This improves the drawback of conventional polyolefins, namely, low affinity with other materials, such as adhesion and paintability. For example, it is expected that the adhesion between polypropylene and carbon fiber will be improved, and the strength of carbon fiber-reinforced polypropylene will be improved.

Claims

1. providing a raw polyolefin; A step of continuously pyrolyzing the prepared raw material polyolefin at a pyrolysis temperature of 300° C. or higher. A method for producing a molded article of a pyrolyzed polyolefin having a double bond, comprising: The thermal decomposition time is 30 seconds or more and 1200 seconds or less, The number average molecular weight of the pyrolyzed polyolefin having a double bond is 1,000 or more and 50,000 or less, the raw material polyolefin has no tertiary carbon or quaternary carbon in its side chain, The method for producing a molded article of a pyrolytic polyolefin having a double bond, wherein the molded article of a pyrolytic polyolefin having a double bond is a film-like or sheet-like molded article.

2. The method according to claim 1, wherein the pyrolysis temperature is 300°C or higher and 500°C or lower.

3. 3. The method according to claim 1, wherein the thermal decomposition time is from 50 seconds to 900 seconds.

4. 4. The method according to claim 1, wherein the raw material polyolefin having no tertiary or quaternary carbon in its side chain is a polyolefin having a monomer unit of a chain olefin having 2 to 10 carbon atoms.

5. The method according to any one of claims 1 to 4, wherein the raw material polyolefin having no tertiary carbon or quaternary carbon in its side chain is a polymer containing ethylene, propylene and / or 1-butene as monomer constituent units, and the pyrolytic polyolefin having a double bond is a pyrolytic polyolefin having a double bond only at its terminal.

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