JP2010235787A - Method for producing halogen-modified olefinic polymer pellet - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for facilitating the recovery of a polymer after the reaction by suppressing the adhesion of the polymer to a reactor wall or agitation blades in halogenating a polyolefin having a relatively low melting point and being difficult to isolate from a solution. <P>SOLUTION: Pellets of an olefin polymer selected from among specified α-olefin (co)polymers and having a melting point of 20 to below 70°C and a number-average molecular weight in the range of 5×10<SP>3</SP>to 1×10<SP>6</SP>are reacted with a halogenating agent under conditions in which the pellets are not molten(namely, dispersed in water at 20-50°C) to produce halogen-modified olefinic polymer pellets. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a method for producing halogen-modified olefin polymer pellets.

  The halogenated polyolefin having a specific halogenated alkyl structure at the terminal or inside of the polyolefin main chain acts as a macroinitiator for the atom transfer radical polymerization reaction. It is disclosed that a block / graft copolymer in which a polyolefin segment and a polar segment are chemically bonded is produced by this atom transfer radical polymerization reaction (see Patent Documents 1 to 3).

  As a method for producing a halogenated polyolefin used as a macroinitiator, a powdery or pelleted polyolefin is generally dissolved in an appropriate solvent, and then halogenated with a halogenating agent such as N-bromosuccinimide, and then the macroinitiator. Or an organic compound having a specific alkyl halide structure that can serve as an initiator of atom transfer radical polymerization and a polyolefin are reacted in a solvent to be converted into a macroinitiator. And the halogenated polyolefin is collect | recovered by pouring the solution containing the obtained macroinitiator in a lot of poor solvents, or cooling and depositing a powdery polymer and filtering.

  However, when the melting point of the polyolefin used as a raw material is low, the crystallinity of the polymer obtained after the halogenation reaction is low, so that it is difficult to precipitate the polymer by the above method or even if it can be precipitated. Even if it is immediately aggregated, in addition to recovery by filtration, it often adheres to the reactor wall or stirring blade, making it impossible to take out the reactor itself.

International Publication No. 2006/088197 Pamphlet JP 2007-169318 A JP 2004-131620 A

  In such a situation, the problem to be solved by the present inventors is to provide a method for easily recovering the halogenated polyolefin after the halogenation reaction from the reaction solution even if the melting point of the polyolefin raw material is relatively low. That is. That is, it is to provide a method for facilitating the recovery by suppressing the adhesion of the polymer after the reaction to the reactor wall and the stirring blade.

The method for producing halogen-modified olefin polymer pellets according to the present invention is a polymer selected from the group consisting of the following (A1) to (A5), having a melting point of 20 ° C. or higher and lower than 70 ° C., and a number average molecular weight. Olefin polymer pellets having a range of 5 × 10 ³ to 1 × 10 ⁶ under conditions where the pellets do not melt (that is, dispersed in water at 20 ° C. or higher and 50 ° C. or lower) It is characterized by reacting.
(A1) A homopolymer or copolymer of an α-olefin compound represented by CH ₂ ═CH—C _X H _{2X + 1} (x is 0 or a positive integer).
(A2) A copolymer of an α-olefin compound represented by CH ₂ ═CH—C _X H _{2X + 1} (x is 0 or a positive integer) and a monoolefin compound having an aromatic ring.
(A3) A copolymer of an α-olefin compound represented by CH ₂ ═CH—C _X H _{2X + 1} (x is 0 or a positive integer) and a cyclic monoolefin compound represented by the following general formula (1).
(A4) A random copolymer of an α-olefin compound represented by CH ₂ ═CH—C _X H _{2X + 1} (x is 0 or a positive integer) and an unsaturated carboxylic acid or a derivative thereof.
(A5) A polymer obtained by modifying the polymer represented by (A1) to (A4) with an unsaturated carboxylic acid or a derivative thereof.

（式（１）において、ｎは０または１であり、ｍは０または正の整数であり、ｑは０または１であり、Ｒ^１〜Ｒ^１８ならびにＲ^ａおよびＲ^ｂは、それぞれ独立に、水素原子、ハロゲン原子および炭化水素基よりなる群から選ばれる原子または基を表し、Ｒ^１５〜Ｒ^１８は、互いに結合して単環または多環を形成していてもよい。）

(In Formula (1), n is 0 or 1, m is 0 or a positive integer, q is 0 or 1, and R ^{1 to} R ¹⁸ and R ^a and R ^b are each independently, Represents an atom or group selected from the group consisting of a hydrogen atom, a halogen atom and a hydrocarbon group, and R ^{15 to} R ¹⁸ may be bonded to each other to form a monocyclic or polycyclic ring.

  In the method for producing halogen-modified olefin polymer pellets according to the present invention, raw material pellets having a relatively low melting point and difficult to isolate from a solution state are halogenated without dissolving them in a solvent. Therefore, there is no need for a step of precipitating the produced polymer after the reaction, and there is little adhesion of the produced polymer to the reactor wall and stirring blade, and the produced polymer can be easily recovered. Moreover, since efficient filtration and washing can be performed without agglomerating the polymer, it is possible to obtain a polymer with less coloring and good properties. Moreover, since water is used as the reaction solvent, a process with high safety in terms of environment and hygiene can be constructed.

Hereinafter, the method for producing the halogen-modified olefin polymer pellet of the present invention will be specifically described.
The present invention relates to a method for producing halogen-modified olefin polymer pellets, characterized in that specific olefin polymer pellets having a relatively low melting point are reacted with a halogenating agent under conditions where the pellets do not melt. More specifically, the pellet is dispersed in water and reacted with a halogenating agent at a temperature of 20 ° C. or higher and 50 ° C. or lower.

  The olefin polymer pellet used as a raw material in the present invention has a melting point measured by DSC in the range of 20 ° C. or higher and lower than 70 ° C., preferably 30 ° C. or higher and lower than 70 ° C.

  An olefin polymer having a melting point of 70 ° C. or higher has a relatively high crystallinity, so that the halogenation reaction may be difficult if the pellets remain as they are. A polymer having a melting point of 70 ° C. or higher can be cooled and precipitated after the polymer is dissolved, and hardly adheres to the reactor or stirring blade. Low need to do. On the other hand, in the case of a polymer having a melting point of less than 20 ° C., the crystallinity is too low, so that the pellets are likely to be fused even at room temperature, and it may be difficult to stably produce halogen-modified polymer pellets.

Moreover, the olefin polymer pellet used as a raw material in the present invention has a polystyrene-equivalent number average molecular weight measured by GPC in the range of 5 × 10 ³ to 1 × 10 ⁶ , preferably 1 × 10 ^{4 to} 5. It is * 10 < ⁵ >, More preferably, it is 1 * 10 < ⁴ > -3 * 10 < ⁵ >.

  Furthermore, the olefin polymer pellet used in the present invention is preferably composed of a monoolefin compound having only one carbon-carbon double bond or a monoolefin compound having an aromatic ring. On the other hand, compounds having a plurality of carbon-carbon double bonds (for example, linear diene compounds such as hexadiene and octadiene, styrene-based diene compounds such as divinylbenzene, and cyclic diolefin compounds such as vinyl norbornene and ethylidene norbornene) The use of polymer pellets as a polymer component is not preferred because unsaturated bonds derived from diene compounds are cross-linked and gelled at the stage of the halogenation reaction described below.

  Therefore, in the present invention, as the olefin polymer pellet to be halogenated, an olefin polymer pellet selected from the group consisting of the following (A1) to (A5) is used. Two or more olefin polymers selected from the group consisting of the following (A1) to (A5) may be used in combination.

式（１）におけるｎ、ｍ、ｑ、Ｒ^１〜Ｒ^１８ならびにＲ^ａおよびＲ^ｂの定義は後述する。 (A1) A homopolymer or copolymer of an α-olefin compound represented by CH ₂ ═CH—C _X H _{2X + 1} (x is 0 or a positive integer).
(A2) A copolymer of an α-olefin compound represented by CH ₂ ═CH—C _X H _{2X + 1} (x is 0 or a positive integer) and a monoolefin compound having an aromatic ring.
(A3) A copolymer of an α-olefin compound represented by CH ₂ ═CH—C _X H _{2X + 1} (x is 0 or a positive integer) and a cyclic monoolefin compound represented by the following general formula (1).
(A4) A random copolymer of an α-olefin compound represented by CH ₂ ═CH—C _X H _{2X + 1} (x is 0 or a positive integer) and an unsaturated carboxylic acid or a derivative thereof.
(A5) A polymer obtained by modifying the polymer represented by (A1) to (A4) with an unsaturated carboxylic acid or a derivative thereof.

The definitions of n, m, q, R ^{1 to} R ¹⁸ and R ^a and R ^{b in} the formula (1) will be described later.

Homopolymer or Copolymer (A1) The homopolymer or copolymer (A1) used in the present invention is represented by CH ₂ ═CH—C _X H _{2X + 1} (x is 0 or a positive integer). -A homopolymer or copolymer of an olefin compound. Specific examples of the α-olefin compound represented by CH ₂ ═CH—C _X H _{2X + 1} (x is 0 or a positive integer) include ethylene, propylene, 1-butene, 1-pentene, and 3-methyl-1. -Butene, 1-hexene, 4-methyl-1-pentene, 3-methyl-1-pentene, 1-octene, 1-decene, 1-dodecene, 1-tetradecene, 1-hexadecene, 1-octadecene, 1-eicosene Examples thereof include linear or branched α-olefins having 4 to 20 carbon atoms. Among these exemplified olefins, it is preferable to use at least one olefin selected from ethylene, propylene, 1-butene, 1-hexene, 4-methyl-1-pentene and 1-octene, more preferably. Uses ethylene, propylene or 1-butene.

  The homopolymer or copolymer (A1) used in the present invention is not particularly limited as long as it is obtained by homopolymerizing or copolymerizing the α-olefin compound, but an ethylene-propylene copolymer, Ethylene-butene copolymer, ethylene-hexene copolymer, ethylene-octene copolymer, ethylene- (4-methyl-1-pentene) copolymer, propylene-butene copolymer, propylene- (4-methyl-) (1-pentene) copolymer, propylene-hexene copolymer, propylene-octene copolymer and the like are preferable. Of these, an ethylene-propylene copolymer and an ethylene-butene copolymer are more preferable.

Copolymer (A2) The copolymer (A2) used in the present invention comprises an α-olefin compound represented by CH ₂ ═CH—C _X H _{2X + 1} (x is 0 or a positive integer), an aromatic ring. It is a copolymer with the monoolefin compound which has. Examples of the α-olefin compound represented by CH ₂ ═CH—C _X H _{2X + 1} (x is 0 or a positive integer) include the α-olefin compounds described in the section of the polymer (A1). Specific examples of the monoolefin compound having an aromatic ring include styrene compounds such as styrene, vinyltoluene, α-methylstyrene, chlorostyrene, styrenesulfonic acid and salts thereof, and vinylpyridine.

  The copolymer (A2) used in the present invention is not particularly limited as long as it is obtained by copolymerizing the α-olefin compound and a monoolefin compound having an aromatic ring, but preferably ethylene-styrene. Examples include copolymers, propylene-styrene copolymers, ethylene-propylene-styrene terpolymers, and ethylene-butene-styrene terpolymers. The content of the unit derived from the α-olefin compound contained in the copolymer (A2) is preferably 50 mol% or more, more preferably 60 mol% or more in order to maintain the properties as an olefin polymer. .

Copolymer (A3) The copolymer (A3) used in the present invention is composed of an α-olefin compound represented by CH ₂ ═CH—C _X H _{2X + 1} (x is 0 or a positive integer), and the following general formula: It is a copolymer with the cyclic monoolefin compound represented by (1). Examples of the α-olefin compound represented by CH ₂ ═CH—C _X H _{2X + 1} (x is 0 or a positive integer) include the α-olefin compounds described in the section of the polymer (A1).

In the above formula (1), n is 0 or 1, m is 0 or a positive integer, and q is 0 or 1. R ^{1 to} R ¹⁸ each independently represents an atom or group selected from the group consisting of a hydrogen atom, a halogen atom and a hydrocarbon group. In the above formula (1), R ^a and R ^b each independently represents an atom or group selected from the group consisting of a hydrogen atom, a halogen atom and a hydrocarbon group when q is 1, q is 0 In the case of, each bond joins to form a 5-membered ring.

The halogen atom represented by R ^{1 to} R ¹⁸ and R ^a and R ^b is a fluorine atom, a chlorine atom, a bromine atom or an iodine atom. Moreover, as a hydrocarbon group, a C1-C20 alkyl group, a C1-C20 halogenated alkyl group, and a C3-C15 cycloalkyl group are each independently mentioned normally, respectively. More specifically, examples of the alkyl group include a methyl group, an ethyl group, a propyl group, an amyl group, a hexyl group, an octyl group, a decyl group, a dodecyl group, and an octadecyl group. Examples of the halogenated alkyl include groups in which at least part of the hydrogen atoms forming the alkyl group as described above is substituted with a fluorine atom, a chlorine atom, a bromine atom or an iodine atom. A cyclohexyl group is mentioned as a cycloalkyl group.

Further, in the general formula (1), R ¹⁵ and R ¹⁶ are R ¹⁷ and R ¹⁸ , R ¹⁵ and R ¹⁷ are R ¹⁶ and R ¹⁸ , R ¹⁵ and R ¹⁸ are R ¹⁶ and R ¹⁷ may be bonded to each other (in cooperation with each other) to form a monocyclic or polycyclic ring. Specific examples of the monocyclic or polycyclic ring formed here include the following.

In the above examples, the carbon atom numbered 1 and the carbon atom numbered 2 are the carbon atom to which R ¹⁵ and R ¹⁶ are bonded, and R ¹⁷ and R ¹⁸ , respectively, in the general formula (1). Represents a carbon atom to which is bonded.

Specific examples of the cyclic olefin represented by the general formula (1) include a bicyclo [2.2.1] hept-2-ene derivative, a tricyclo [4.3.0.1 ^2,5 ] -3-decene derivative, and a tricyclo [ 4.3.0.1 ^{2, 5]-3-undecene} derivative, tetracyclo [4.4.0.1 ^2,5 .1 ^7,10] -3- dodecene derivatives, pentacyclo [7.4.0.1 ^2,5 .1 ^9,12 .0 ^{8, 13]} -3-pentadecene derivatives, pentacyclo ^{[6.5.1.1 3,6 .0 2,7 .0 9,13]} -4- pentadecene derivatives, pentacyclo [8.4.0.1 ^2,3 .1 ^9,12 .0 ^{8, 13]} -3-hexadecene derivative, pentacyclo ^{[6.6.1.1 3,6 .0 2,7 .0 9,14]} -4- hexadecene derivatives, penta cyclopentadiene decadiene derivative, hexacyclo [6.6.1.1 ^{3, 6} .1 ^10,13 .0 ^2,7 .0 ^9,14] -4-heptadecene derivatives, heptacyclo ^{[8.7.0.1 3,6 .1 10,17 .1 12,15 .0} 2,7 .0 11,16] - 4-eicosene derivatives, heptacyclo-5-eicosene derivatives, hep Cyclo ^{[8.8.0.1 4,7 .1 11,18 .1 13,16 .0} 3,8 .0 12,17] -5- heneicosene derivatives, octacyclo [8.8.0.1 ^2,9 .1 ^4,7 .1 ^11,18 .1 ^13,16 .0 ^3,8 .0 ^12,17] -5-docosene derivatives, Nonashikuro ^{[10.9.1.1 4,7 .1 13,20 .1 15,18 .0} 3,8 .0 ^2,10 .0 ^12,21 .0 ^14,19] -5-pentacosene derivatives, Nonashikuro ^{[10.10.1.1 5,8 .1 14,21 .1 16,19 .0} 2,11 .0 4,9 .0 ^{13, 22} .0 ^15,20] -5-hexacosenoic derivatives.

  The cyclic monoolefin compound represented by the general formula (1) can be produced by subjecting cyclopentadiene and an olefin having a corresponding structure to Diels-Alder reaction. These cyclic olefins can be used alone or in combination of two or more.

式（２）において、ｎ、ｍ、ｑ、Ｒ^１〜Ｒ^１８ならびにＲ^ａおよびＲ^ｂは式（１）と同じ意味である。 The structural unit derived from the cyclic monoolefin compound represented by the general formula (1) is represented by the following general formula (2).

In the formula (2), n, m, q, R ^{1 to} R ¹⁸ and R ^a and R ^b have the same meaning as in the formula (1).

The copolymer (A3) used in the present invention is not particularly limited as long as it is obtained by copolymerizing the α-olefin compound and the cyclic monoolefin compound, but preferably ethylene and bicyclo [2.2. 1] a copolymer of hept-2-ene, and copolymers of ethylene and tetracyclo [4.4.0.1 ^2,5 .1 ^7,10] -3- dodecene. The content of the unit derived from the α-olefin compound contained in the copolymer (A3) is preferably 50 mol% or more, more preferably 60 mol% or more in order to maintain the properties as an olefin polymer. .

About Random Copolymer (A4) The polymer (A4) used in the present invention includes an α-olefin compound represented by CH ₂ ═CH—C _X H _{2X + 1} (x is 0 or a positive integer), an unsaturated carboxylic acid, A random copolymer with an acid or a derivative thereof. Examples of the α-olefin compound represented by CH ₂ ═CH—C _X H _{2X + 1} (x is 0 or a positive integer) include the α-olefin compounds described in the section of the polymer (A1). As unsaturated carboxylic acid or its derivative (s), unsaturated monocarboxylic acid and its derivative (s), unsaturated dicarboxylic acid and its derivative (s), and vinyl esters are mentioned, for example. Specifically, (meth) acrylic acid, (meth) acrylic acid ester, (meth) acrylic acid halide, (meth) acrylic acid amide, maleic acid, maleic anhydride, maleic acid ester, maleic acid halide, maleic acid Examples include amides, maleic imides, aliphatic vinyl esters such as vinyl acetate and vinyl butyrate.

  The random copolymer (A4) used in the present invention is not particularly limited as long as it is a random copolymer of the above α-olefin compound and an unsaturated carboxylic acid or a derivative thereof, but preferably ethylene- (meta ) Acrylic acid copolymer, ethylene- (meth) acrylic acid ester copolymer, ethylene-maleic anhydride copolymer, ethylene-vinyl acetate copolymer. The content of the unit derived from the α-olefin compound contained in the copolymer (A4) is preferably 50 mol% or more, more preferably 60 mol% or more in order to maintain the properties as an olefin polymer. .

About Modified Polymer (A5) The polymer (A5) used in the present invention is obtained by modifying the polymers (A1) to (A4) with an unsaturated carboxylic acid or a derivative thereof. Specific examples of the unsaturated carboxylic acid or derivative thereof for modification include maleic acid, maleic anhydride, maleic ester, maleic halide, maleic amide, maleic imide and the like. Of these, maleic anhydride is preferred.

  As a method for modifying the polymers (A1) to (A4) with an unsaturated carboxylic acid or a derivative thereof, for example, in the presence of a radical generator such as an organic peroxide, or in the presence of ultraviolet rays or radiation, Examples thereof include a method in which an unsaturated carboxylic acid or a derivative thereof is reacted with the polymers (A1) to (A4).

  There are no particular restrictions on the conditions and method for producing an olefin polymer selected from the group consisting of (A1) to (A5), but known transition metals such as Ziegler-Natta catalysts, metallocene catalysts, post-metallocene catalysts, etc. Methods such as coordination anion polymerization using a catalyst and radical polymerization under high pressure or irradiation can be used. Further, the olefin polymer produced by the above method may be produced by thermal decomposition or radical decomposition.

  Examples of the shape of the polymer pellet used in the present invention include a spherical shape, a cylindrical shape, a lens shape, and a cubic shape. These can be produced by known pelletizing methods. For example, the polymer obtained by polymerization by the above method is uniformly melt-mixed, extruded with an extruder, and then hot cut or strand cut to obtain spherical, cylindrical, or lens-like pellets. . The cutting in this case may be performed in any of air currents such as water and air. The cubic pellets can be obtained by, for example, uniformly mixing, forming into a sheet shape with a roll or the like, and using a sheet pelletizing machine. As for the size of the pellet, the length of the longest part of the pellet is preferably 3 cm or less.

  Specific examples of the halogenating agent used in the present invention include chlorine, bromine, iodine, phosphorus trichloride, phosphorus tribromide, phosphorus triiodide, phosphorus pentachloride, phosphorus pentabromide, phosphorus pentaiodide, Thionyl chloride, sulfuryl chloride, thionyl bromide, N-chlorosuccinimide, N-bromosuccinimide, N-bromocaprolactam, N-bromophthalimide, 1,3-dibromo-5,5-dimethylhydantoin, N-chloroglutarimide, N -Bromoglutarimide, N, N'-dibromoisocyanuric acid, N-bromoacetamide, N-bromocarbamic acid ester, dioxane dibromide, phenyltrimethylammonium tribromide, pyridinium hydrobromide perbromide, pyrrolidone hydrotribromide, hypochlorous acid T-butyl acid, t-butyl hypobromite, copper (II) chloride, copper bromide ( II), iron (III) chloride, oxalyl chloride, IBr and the like. Of these, chlorine, bromine, N-chlorosuccinimide, N-bromosuccinimide, N-bromocaprolactam, N-bromophthalimide, 1,3-dibromo-5,5-dimethylhydantoin, N-chloroglutarimide, N -Bromoglutarimide, N, N'-dibromoisocyanuric acid; more preferably bromine, and N-bromosuccinimide, N-bromocaprolactam, N-bromophthalimide, 1,3-dibromo-5,5-dimethylhydantoin, It is a compound having an N-Br bond such as N-bromoglutarimide and N, N′-dibromoisocyanuric acid.

  The reaction between the olefin polymer pellets selected from (A1) to (A5) and the halogenating agent is preferably performed in an inert gas atmosphere. Examples of the inert gas include inert gases such as nitrogen, argon, and helium.

  In the reaction with the halogenating agent, a radical initiator may be added as necessary to accelerate the reaction. Examples of the radical initiator include azobisisobutyronitrile, azobis-2,4-dimethylvaleronitrile, azobiscyclohexanecarbonitrile, azobis-2-amidinopropane hydrochloride, azobisisobutyric acid dimethyl, azobisisobutylamidine hydrochloride Or an azo initiator such as 4,4′-azobis-4-cyanovaleric acid; benzoyl peroxide, 2,4-dichlorobenzoyl peroxide, di-tert-butyl peroxide, lauroyl peroxide, acetyl peroxide, peroxy Diisopropyl oxide dicarbonate, cumene hydroperoxide, tert-butyl hydroperoxide, dicumyl peroxide, p-menthane hydroperoxide, pinane hydroperoxide, methyl ethyl ketone peroxide, cyclohexanone peroxide, diisopropyl peroxydicarbonate, tert-butyl Peroxide initiators such as ruoxylaurate, di-tert-butylperoxyphthalate, dibenzyl oxide or 2,5-dimethylhexane-2,5-dihydroperoxide; and benzoyl peroxide-N, N-dimethylaniline Alternatively, redox initiators such as peroxodisulfuric acid-sodium hydrogen sulfite are listed.

  Of these, azo initiators or peroxide initiators are preferred, and more preferred are benzoyl peroxide, di-tert-butyl peroxide, lauroyl peroxide, acetyl peroxide, diisopropyl dicarbonate, cumene hydro Peroxide, tert-butyl hydroperoxide, dicumyl peroxide, azobisisobutyronitrile, azobis-2,4-dimethylvaleronitrile, azobiscyclohexanecarbonitrile, dimethyl azobisisobutyrate.

  These radical initiators may be used alone or in combination of two or more; they may be added to the polymerization reaction system all at once or sequentially.

  In the present invention, in order to cause the olefin polymer pellet selected from (A1) to (A5) to react with the halogenating agent, the halogenating agent and, if necessary, a radical, under conditions where the pellet does not melt. An initiator or the like may be added to the polymerization reaction system and reacted. More specifically, the pellets are dispersed in an aqueous solvent and maintained at a temperature of 20 ° C. or higher and 50 ° C. or lower, more preferably 30 ° C. or higher and 50 ° C. or lower, and further preferably 40 ° C. or higher and 50 ° C. or lower. And a method in which a radical initiator or the like is added and mixed as necessary. In addition, the reaction may be carried out under reduced pressure, normal pressure, or pressurized conditions depending on circumstances.

  In the present invention, water is used as a reaction solvent, which not only has an advantage of being able to construct a process that is highly safe in terms of environment and hygiene, but also at a relatively high temperature compared to the case of using an organic solvent as a reaction solvent. However, there is also an advantage that the halogenation reaction can be efficiently performed without melting the pellet.

  If the halogenation reaction temperature is lower than 20 ° C., the reactivity of the halogenation reaction may be reduced. In general, the higher the reaction temperature, the more efficiently the halogenation reaction can be achieved, but the yield is reduced (due to melting of the pellet, adhesion to the reactor wall or stirring blade, etc.) There is a risk that the quality of the pellets may be deteriorated (for example, due to homogenization or fusion between the pellets). In the present invention, if the olefin polymer is halogenated at a high temperature exceeding 50 ° C., the yield of the halogen-modified olefin polymer pellet may be lowered; the temperature higher than the melting point of the olefin polymer (70 ° C. When the halogenation is performed as described above, not only the yield but also the quality may be lowered.

  The halogen-modified olefin polymer pellets produced by the above-described method are preferably washed. As the washing method, various conventionally known methods can be used. For example, the obtained halogen-modified olefin polymer pellets are suspended in a solvent in which the pellets are not dissolved and stirred for a certain time, followed by filtration. The method of doing is mentioned. By this operation, the solvent used for the halogenation, the unreacted halogenating agent, the radical initiator, the reaction residue derived from those compounds, and the like can be removed.

  Any solvent can be used as the solvent used for washing the halogen-modified olefin polymer pellets as long as it dissolves unreacted substances and reaction residues. Specifically, aromatic hydrocarbon solvents such as benzene, toluene and xylene; aliphatic hydrocarbon solvents such as pentane, hexane, heptane, octane, nonane and decane; such as cyclohexane, methylcyclohexane and decahydronaphthalene Alicyclic hydrocarbon solvents: Chlorinated hydrocarbon solvents such as chlorobenzene, dichlorobenzene, trichlorobenzene, methylene chloride, chloroform, carbon tetrachloride and tetrachloroethylene; methanol, ethanol, n-propanol, iso-propanol, n Alcohol solvents such as butanol, sec-butanol and tert-butanol; ketone solvents such as acetone, methyl ethyl ketone and methyl isobutyl ketone; ester solvents such as ethyl acetate, butyl acetate and dimethyl phthalate; It can be exemplified dimethyl sulfoxide, N, N- dimethylformamide, dioxane, water and the like; Le, diethyl ether, di -n- amyl ether, diphenyl ether, ether solvents such as tetrahydrofuran and anisole.

  Among these, alcohol solvents, ketone solvents, ester solvents, ether solvents, dimethyl sulfoxide, N, N-dimethylformamide, dioxane, water, which are solvents that do not dissolve the obtained halogen-modified olefin polymer pellets Either is preferred; more preferred are alcohol solvents and ketone solvents.

  EXAMPLES Hereinafter, although this invention is demonstrated further more concretely based on an Example, this invention is not limited to these Examples.

The physical properties in the examples were measured as follows.
(i) Measurement of molecular weight and molecular weight distribution GPC (gel permeation chromatography) was used for measurement under the following conditions.
Measuring device: alliance GPC2000 (manufactured by Waters)
Analysis device: Empower Professional (manufactured by Waters)
Column: TSKgel GMH6HT x 2 + TSKgel GMH6HTL x 2
Column temperature: 140 ° C
Mobile phase: o-dichlorobenzene (ODCB)
Detector: differential refractometer flow rate: 1 mL / min
Sample concentration: 30 mg / 20 mL-ODCB
Injection volume: 500 μL
Column calibration: monodisperse polystyrene (manufactured by Tosoh Corporation)

(ii) Analysis of halogen content The sample was precisely weighed in a quartz sample boat and burned and decomposed at 900 ° C. in an Ar / O ₂ stream. The generated gas was absorbed into the absorbing solution and the volume was adjusted with pure water. The amount of halogen contained in this test solution was quantified by ion chromatography.
Ion chromatograph: DX-500 (Dionex)
Column: IonPacAS12A (manufactured by Dionex)

[Example 1]
Halogenation of ethylene / 1-butene copolymer (EBR) pellets Into a 1 L glass reactor sufficiently purged with nitrogen, 150 g of EBR pellets (Mn = 131,000; melting point = 35.7 ° C.) and distilled water 750 ml was added and stirred at 25 ° C. for 2 hours under a nitrogen atmosphere. Thereafter, 0.75 ml of bromine was added in the dark and reacted at 25 ° C. for 2 hours. After the reaction, the inside of the reactor was in a state where red-orange pellets were dispersed in the yellow liquid, and polymer adhesion to the reactor wall and stirring blades and blocking of the pellets were not observed. The reaction solution was filtered through a glass filter, the pellet on the filter was put in 2 L of acetone, stirred for 1 hour, and then filtered again to dry the pellet obtained at room temperature under reduced pressure. The polymer after drying was a colorless and transparent pellet, and there was no blocking.

  The content of bromine atoms contained in the obtained polymer was 0.20 wt% from ion chromatography analysis. When the molecular weight (converted to PS) of the polymer was measured by GPC, it was Mw = 189,000, Mn = 99,200, and Mw / Mn = 1.9. The results are shown in Table 1.

[Example 2]
Halogenation of ethylene / 1-butene copolymer (EBR) pellets The reaction was performed under the same conditions as in Example 1 except that the amount of bromine added was 1.5 mL. After the reaction, the inside of the reactor was in a state where red-orange pellets were dispersed in the yellow liquid, and polymer adhesion to the reactor wall and stirring blades and blocking of the pellets were not observed. The reaction solution was filtered through a glass filter, the pellet on the filter was put in 2 L of acetone, stirred for 1 hour, and then filtered again to dry the pellet obtained at room temperature under reduced pressure. The polymer after drying was a colorless and transparent pellet, and there was no blocking. The results are shown in Table 1.

[Example 3]
Halogenation of ethylene / 1-butene copolymer (EBR) pellets The reaction was performed under the same conditions as in Example 1 except that the reaction temperature was 50 ° C. After the reaction, the inside of the reactor was in a state where red-orange pellets were dispersed in the yellow liquid, and polymer adhesion to the reactor wall and stirring blades and blocking of the pellets were not observed. The reaction solution was filtered through a glass filter, the pellet on the filter was put in 2 L of acetone, stirred for 1 hour, and then filtered again to dry the pellet obtained at room temperature under reduced pressure. The polymer after drying was a colorless and transparent pellet, and there was no blocking. The results are shown in Table 1.

[Example 4]
Halogenation of ethylene / 1-butene copolymer (EBR) pellets The reaction was performed under the same conditions as in Example 2 except that the reaction temperature was 50 ° C. After the reaction, the inside of the reactor was in a state where red-orange pellets were dispersed in the yellow liquid, and polymer adhesion to the reactor wall and stirring blades and blocking of the pellets were not observed. The reaction solution was filtered through a glass filter, the pellet on the filter was put in 2 L of acetone, stirred for 1 hour, and then filtered again to dry the pellet obtained at room temperature under reduced pressure. The polymer after drying was a colorless and transparent pellet, and there was no blocking. The results are shown in Table 1.

[Comparative Example 1]
Halogenation of ethylene / 1-butene copolymer (EBR) pellets Into a 500 mL glass reactor sufficiently purged with nitrogen, 40 g of EBR pellets similar to those used in Example 1 and 400 ml of distilled water were placed. The mixture was stirred at 25 ° C. for 2 hours under a nitrogen atmosphere. Thereafter, 0.4 ml of bromine was added in the dark and reacted at 70 ° C. for 2 hours. After the reaction, the inside of the reactor was in a state in which red-orange pellets were adhered to each other in the yellow liquid, and some of the pellets were melted and adhered to the reactor wall and stirring blades.

  When the reaction solution was filtered with a glass filter, some of the polymer remained strongly attached to the reactor wall and the stirring blade and was not easily peeled off. After filtration, the polymer on the filter was put into 2 L of acetone and stirring was attempted. After immersion in acetone for 1 hour, the polymer obtained by filtration again was dried under reduced pressure at room temperature. The polymer after drying was in the form of colorless and transparent pellets, but most of the pellets remained blocked. The results are shown in Table 1.

[Comparative Example 2]
Halogenation of ethylene / 1-butene copolymer (EBR) pellets 75 g of EBR pellets similar to those used in Example 1 and 1.5 L of chlorobenzene were placed in a 2 L glass reactor sufficiently purged with nitrogen. When the mixture was stirred at 25 ° C. for 2 hours under a nitrogen atmosphere, a uniform solution was obtained. Thereafter, 0.8 ml of bromine was added in the dark and reacted at 100 ° C. for 2 hours. The inside of the reactor after the reaction was a brown uniform solution. When 500 mL of acetone was added to the reaction solution under stirring, the polymer was precipitated in a lump and strongly adhered to the reactor wall and the stirring blade, making stirring impossible. The precipitated bulk polymer was scraped with a spatula and dried under reduced pressure at 120 ° C. to obtain a brown rubbery polymer. The results are shown in Table 1.

[Example 5]
Halogenation of ethylene / 1-butene copolymer (EBR) pellets Into a glass reactor with an internal volume of 500 mL sufficiently purged with nitrogen, 60 g of EBR pellets (Mn = 91,000; melting point = 66.3 ° C.) and distilled water 300 ml was added and stirred at 25 ° C. for 2 hours under a nitrogen atmosphere. Thereafter, 0.6 ml of bromine was added in the dark and reacted at 50 ° C. for 2 hours. After the reaction, the inside of the reactor was in a state where red-orange pellets were dispersed in the yellow liquid, and polymer adhesion to the reactor wall and stirring blades and blocking of the pellets were not observed. The reaction solution was filtered through a glass filter, the pellet on the filter was placed in 1 L of acetone, stirred for 1 hour, and then filtered again to dry the pellet obtained at room temperature under reduced pressure. The polymer after drying was a colorless and transparent pellet, and there was no blocking. The results are shown in Table 1.

[Comparative Example 3]
Halogenation of ethylene / 1-butene copolymer (EBR) pellets Into a glass reactor having an internal volume of 500 mL sufficiently purged with nitrogen, 60 g of EBR pellets (Mn = 60,000; melting point = 76.8 ° C.) and distilled water 300 ml was added and stirred at 25 ° C. for 2 hours under a nitrogen atmosphere. Thereafter, 0.6 ml of bromine was added in the dark and reacted at 50 ° C. for 2 hours. After the reaction, the inside of the reactor was in a state where red-orange pellets were dispersed in the yellow liquid, and polymer adhesion to the reactor wall and stirring blades and blocking of the pellets were not observed. The reaction solution was filtered through a glass filter, the pellet on the filter was placed in 1 L of acetone, stirred for 1 hour, and then filtered again to dry the pellet obtained at room temperature under reduced pressure. The polymer after drying was a colorless and transparent pellet, and there was no blocking. The results are shown in Table 1.

[Example 6]
Halogenation of ethylene / propylene copolymer (EPR) pellets Into a glass reactor with an internal volume of 500 mL sufficiently purged with nitrogen, 60 g of EPR pellets (Mn = 51,900; melting point = 33.8 ° C.) and 300 ml of distilled water were added. The mixture was stirred at 25 ° C. for 2 hours under a nitrogen atmosphere. Thereafter, 0.6 ml of bromine was added in the dark and reacted at 50 ° C. for 2 hours. After the reaction, the inside of the reactor was in a state where red-orange pellets were dispersed in the yellow liquid, and polymer adhesion to the reactor wall and stirring blades and blocking of the pellets were not observed. The reaction solution was filtered through a glass filter, the pellet on the filter was placed in 1 L of acetone, stirred for 1 hour, and then filtered again to dry the pellet obtained at room temperature under reduced pressure. The polymer after drying was a colorless and transparent pellet, and there was no blocking. The results are shown in Table 1.

[Comparative Example 4]
Halogenation of Ethylene / Propylene Copolymer (EPR) Pellet 75 g of EPR pellets similar to those used in Example 6 and 1.5 L of chlorobenzene were placed in a 2 L glass reactor sufficiently purged with nitrogen. When the mixture was stirred at 25 ° C. for 2 hours under an atmosphere, a uniform solution was obtained. Thereafter, 0.75 ml of bromine was added in the dark and reacted at 50 ° C. for 2 hours. The inside of the reactor after the reaction was a brown uniform solution. When 500 mL of acetone was added to the reaction solution under stirring, the polymer was precipitated in a lump and strongly adhered to the reactor wall and the stirring blade, making stirring impossible. The precipitated bulk polymer was scraped with a spatula and dried under reduced pressure at 120 ° C. to obtain a pale yellow rubber-like polymer. The results are shown in Table 1.

[Example 7]
Halogenation of ethylene / propylene copolymer (EPR) pellets Into a glass reactor with an internal volume of 500 mL sufficiently purged with nitrogen, 60 g of EPR pellets (Mn = 16,800; melting point = 31.1 ° C.) and 300 ml of distilled water were added. The mixture was stirred at 25 ° C. for 2 hours under a nitrogen atmosphere. Thereafter, 0.6 ml of bromine was added in the dark and reacted at 50 ° C. for 2 hours. After the reaction, the inside of the reactor was in a state where red-orange pellets were dispersed in the yellow liquid, and polymer adhesion to the reactor wall and stirring blades and blocking of the pellets were not observed. The reaction solution was filtered through a glass filter, the pellet on the filter was placed in 1 L of acetone, stirred for 1 hour, and then filtered again to dry the pellet obtained at room temperature under reduced pressure. The polymer after drying was a colorless and transparent pellet, and there was no blocking. The results are shown in Table 1.

[Comparative Example 5]
Halogenation of ethylene / propylene copolymer (EPR) pellets The reaction was performed under the same conditions as in Example 7 except that the reaction temperature was 80 ° C. After the reaction, the inside of the reactor was in a state in which red-orange pellets were adhered to each other in the yellow liquid, and some of the pellets were melted and adhered to the reactor wall and stirring blades. When the reaction solution was filtered with a glass filter, some of the polymer remained strongly attached to the reactor wall and stirring blade, and did not peel off easily. After filtration, the polymer on the filter was put into 2 L of acetone to attempt stirring, but blocking was not achieved and stirring was not possible. After immersion in acetone for 1 hour, the polymer obtained by filtration again was dried under reduced pressure at room temperature. The polymer after drying was in the form of colorless and transparent pellets, but most of the pellets remained blocked. The results are shown in Table 1.

  As shown in Table 1, if the olefin polymer pellets are halogenated in an aqueous solvent at an appropriate temperature, the pellets of the desired halogenated olefin polymer are produced without melting or aggregation of the pellets. It can be seen that can be obtained.

  According to the present invention, even when a polyolefin raw material having a relatively low melting point and difficult to isolate from a solution state is halogenated in a solvent, the halogenated polyolefin as a reaction product adheres to the reactor wall and stirring blade. Since it can suppress, halogenated polyolefin can be collect | recovered easily. Furthermore, since the halogenated polyolefin polymer can be efficiently filtered and washed without agglomerating, it is possible to obtain a halogenated polyolefin polymer with less coloring and good properties. Moreover, since water is used as the reaction solvent, a process with high safety in terms of environment and hygiene can be constructed. Thus, the present invention provides a useful method for producing halogen-modified olefin polymer pellets.

Claims (4)

Among olefin polymers selected from the group consisting of the following (A1) to (A5), the melting point is 20 ° C. or higher and lower than 70 ° C., and the number average molecular weight (in terms of standard polystyrene) is 5 × 10 ³ to 1 × 10. ^6. A process for producing halogen-modified olefin polymer pellets, characterized in that olefin polymer pellets in the range of ⁶ are dispersed in water and reacted with a halogenating agent at 20 to 50 ° C.
(A1) A homopolymer or copolymer of an α-olefin compound represented by CH ₂ ═CH—C _X H _{2X + 1} (x is 0 or a positive integer).
(A2) A copolymer of an α-olefin compound represented by CH ₂ ═CH—C _X H _{2X + 1} (x is 0 or a positive integer) and a monoolefin compound having an aromatic ring.
(A3) A copolymer of an α-olefin compound represented by CH ₂ ═CH—C _X H _{2X + 1} (x is 0 or a positive integer) and a cyclic monoolefin compound represented by the following general formula (1).
(A4) A random copolymer of an α-olefin compound represented by CH ₂ ═CH—C _X H _{2X + 1} (x is 0 or a positive integer) and an unsaturated carboxylic acid or a derivative thereof.
(A5) A polymer obtained by modifying the polymer represented by (A1) to (A4) with an unsaturated carboxylic acid or a derivative thereof.

(In Formula (1), n is 0 or 1, m is 0 or a positive integer, q is 0 or 1, and R ^{1 to} R ¹⁸ and R ^a and R ^b are each independently, And represents an atom or group selected from the group consisting of a hydrogen atom, a halogen atom and a hydrocarbon group, and R ^{15 to} R ¹⁸ may be bonded to each other to form a monocyclic or polycyclic ring)   The production method according to claim 1, wherein the olefin polymer pellets are dispersed in water and reacted with a halogenating agent at 25 ° C or more and 50 ° C or less.   The method according to claim 1 or 2, wherein the olefin polymer is the olefin polymer (A1). The method according to claim 3, wherein the olefin polymer (A1) is an ethylene-propylene copolymer or an ethylene-butene copolymer, and the halogenating agent is bromine.