KR20070080085A - Polyolefin using antistatic agent and manufacturing method thereof - Google Patents

Abstract

Provided are a method for preparing a polyolefin to improve syndiotacticity and polymerization activity by using an antistatic agent, and a polyolefin prepared by the method. The method comprises the steps of polymerizing an alpha-olefin monomer of C3 or more in the presence of an antistatic agent. Preferably the polyolefin is polybutene-1 or polypropylene. A part of the antistatic agent is directly injected into a reactor and another part of the antistatic agent is provided in a form added to a catalyst. Preferably the antistatic agent is selected from the group consisting of a anionic surfactant, a cationic surfactant, an amphiphilic surfactant, or a nonionic surfactant.

Description

Polyolefin prepared using an antistatic agent and a method of preparing the same {Polyolefin prepared using an antistatic agent and a method of preparing the same}

The present invention relates to a polymerization method of α-olefin having 3 or more carbon atoms and to a polyolefin prepared by the above method, and more specifically, to a polyolefin (eg, polypropylene or polybutene-1 by polymerizing α-olefin monomer having 3 or more carbon atoms). ) And a polyolefin produced by the above method.

Commercialization of polybutene-1 in addition to polypropylene, which is mainly used as a general purpose plastic material, began with the development of Mobil's solution process, which has been followed by research on slurry and gas phase processes. In addition, since polybutene-1 generally has excellent characteristics in terms of pressure resistance, creep resistance, and impact strength, development is being made for pipe manufacture and film use.

In particular, process development with high stereoregularity and high activity has been in progress. In general, in order to obtain a polymer having high stereoregularity in polymerizing α-olefin having 3 or more carbon atoms, an electron donor is introduced in advance into the catalyst system (this is called an internal electron donor), and additionally, a polymerization system is introduced. (Called external electron donors) has been used. However, the electron donor used at this time tends to improve the stereoregularity of the polymer to be produced while reducing the polymerization activity.

A closer look at electron donor research can be divided into two categories. First, the synthesis of electron donors with a new structure is examined. Secondly, the existing electron donors are applied to the system to check each characteristic and then to reach the optimum point through proper combination (mixing).

However, electron donors which have been used to date have improved the stereotypic index (I.I.) but have not increased the activity. Therefore, there is a need for improvement.

It is an object of the present invention to provide a process for producing polyolefins with improved stereoregularity and activity.

Another object of the present invention is to provide a polyolefin produced by the above method.

In order to achieve the above object of the present invention, the first aspect of the present invention provides a method for producing a polyolefin by polymerizing an α-olefin monomer having 3 or more carbon atoms in the presence of an antistatic agent.

In order to achieve the above another object of the present invention, a second aspect of the present invention provides a polyolefin produced by the above method.

Polyolefins produced by the process according to the invention exhibit high stereoregularity and improved polymerization activity.

Hereinafter, the present invention will be described in more detail.

The present invention relates to a method for producing a polyolefin containing an α-olefin monomer having 3 or more carbon atoms in the main chain, characterized in that an antistatic agent is added to the polymerization reaction.

In this case, the polymerized polyolefin may be a polypropylene having a main chain having 3 carbon atoms, a polybutene-1 having 4 carbon atoms, or a polyolefin formed of an α-olefin having 5 or more carbon atoms, preferably polypropylene or polybutene-1, More preferably polybutene-1.

Methods of adding an antistatic agent to the polymerization reaction include (i) directly adding the antistatic agent to the reactor, (ii) providing the antistatic agent in the form contained in the catalyst, or (iii) some of the antistatic agent Directly into the reactor and some of them are provided in the form of the catalyst.

As the antistatic agent, the antistatic agent is selected from the group consisting of anionic surfactants, cationic surfactants, amphoteric surfactants and nonionic surfactants, preferably anionic surfactants or nonionic surfactants, most preferably nonionic Surfactant.

The polyolefin prepared by the method of further injecting an antistatic agent into the polymerization reaction system not only improves the stereoregularity thereof but also achieves the effect of improving the polymerization activity. Previously used electron donors improved the isotactic index (I.I), a stereoregularity index, but did not increase activity. In the present invention, by introducing the antistatic agent solved the above problems of the existing electron donor. On the other hand, by additionally injecting an antistatic agent into the polymerization reaction, the amount of external electron donor can be reduced, and by controlling the amount of use of the antistatic agent and the external electron donor, the polymerization performance such as activity and physical properties can be simultaneously extended in a wider range. I can regulate it.

The catalyst used in the polymerization reaction may be supported on inorganic oxides, magnesium compounds, clays or clay minerals, preferably on magnesium compounds, more preferably MgCl ₂ . Such catalysts may include Ti compounds and internal electron donors.

The compound of Ti is TiCl ₃ Or Ti (OR) _n X _4-n and the like halogenated titanium compound (and wherein, R is C _{1 -18} alkyl, n is an integer from 0 to 3, X is halogen). Examples of such a titanium halide compound include titanium tetrahalide such as TiCl ₄ , TiBr ₄ and TiI ₄ ; Ti (OCH ₃₎ Cl _3, alkoxy titanium trihalide such as _{Ti (OC 2 H 5) Cl} 3, Ti (OC 2 H 5) Br 3; Alkoxy titanium dihalide such as Ti (OCH ₃ ) ₂ Cl ₂ , Ti (OC ₂ H ₅ ) ₂ Cl ₂ , Ti (OC ₂ H ₅ ) ₂ Br ₂ ; Alkoxy tritide halides such as Ti (OCH ₃ ) ₃ Cl, Ti (OC ₂ H ₅ ) ₃ Cl, Ti (OC ₂ H ₅ ) ₃ Br, etc. Among them, titanium tetrahalide is preferable, and titanium tetrachloride (TiCl) is particularly preferred. ₄ ) is more preferable.

The internal electron donor is included in the supported catalyst, and the compound which can be used as the internal electron donor includes an ester, ether, amine or ketone compound. The internal electron donor is preferably selected from alkyl, cycloalkyl or aryl esters of monocarboxylic acids such as benzoic acid or polycarboxylic acids (eg phthalic acid or malonic acid), wherein alkyl, cycloalkyl or The aryl group has 1 to 18 carbon atoms. Examples of the electron donor compound include methyl benzoate, ethyl benzoate, diisobutyl phthalate, and the like. The molar ratio of MgCl ₂ (= molar ratio of internal electron donor / MgCl ₂ ) to the internal electron donor used in the preparation of the solid catalyst component is 0.01 to 10, preferably 0.01 to 1, more preferably 0.01 to 0.5.

The cocatalyst component may be supported together with the catalyst for polymerization or further injected into the reaction separately from the catalyst. Alkyl aluminum may be used as the cocatalyst component, and examples thereof include triethylaluminum (TEA), triisobutylaluminum (TIBA), tributylaluminum, trihexylaluminum, trioctylaluminum, and the like, or a mixture thereof. Preferably, triethylaluminum, triisobutylaluminum alone, or its compound is used.

The amount of cocatalyst used in the prepolymerization is used so that the molar ratio of Al / Ti is 1 to 100, preferably 1 to 50, more preferably 5 to 20, and the molar ratio is 10 to 1000, preferably in the main polymerization. Preferably from 50 to 500, more preferably from 100 to 400.

An external electron donor, stabilizer or additive may be further included in the polymerization method of the polyolefin according to the present invention.

The external electron donor may be the same as or different from the internal electron donor. Examples of such external electron donors include silane compounds, ethers, 1,3-diethers, esters, amines, heterocyclic compounds, and the like, and preferably R1 _a R2 _b Si (OR3) _c (wherein R 1, R 2, and R 3 are each independently an alkyl, cycloalkyl, or allyl group, a and b are each an integer of 1 to 2, c is an integer of 1 to 3, and the sum of a, b, and c is 4 Silane compound, more preferably R1 _a R2 _b Si (OR3) _c (where R1 and R2 are each alkyl, cycloalkyl or allyl group, R3 is methyl group, a and b are each 1, c Is an integer of 2, and the sum of a, b, and c is 4), and examples thereof include cyclohexyldimethoxysilane, dicyclopentyldimethoxysilane, diisobutyldimethoxysilane, and the like.

The molar ratio of Ti to the external electron donor used during prepolymerization (molar ratio of the external electron donor / Ti) is 0 to 50, preferably 0 to 20, more preferably 0 to 10, The molar ratio of Ti (external electron donor / Ti) to the external electron donor used is 0.1 to 100, preferably 0.5 to 50, more preferably 5 to 25.

Stabilizers or additives may be added as needed to prevent deformation of the polyolefin due to the high temperature heat required to remove unreacted monomers. As such a tablet or additive, a phenol-based, phosphorus-based or sulfur-based antioxidant commonly used in polyolefin resin can be used.

In the process according to the invention, comonomers which can be added to the polymerization reaction include ethylene, propylene, 3-methyl-1-butene, 1-pentene, 4-methyl-1-pentene, 1-hexene, 1-heptene, 1-decene, 1-undecene, 1-dodecene, 1-tetradecene, 1-hexadecene, 1-ikocene, norbornene, norbonadiene, ethylidenenorbornene, vinylnorbornene, dicyclopentadiene, 1,4-butadiene, 1,5-pentadiene, 1,6-hexadiene, styrene, alpha-methylstyrene, divinylbenzene, 3-chloromethylstyrene, and the like, and preferably an olefin monomer having 2 to 10 carbon atoms, Most preferred are ethylene, propylene, 3-methyl-1butene, 4-methyl-1pentene, 1-hexene, 1-heptene, 1-decene, norbornene.

The reaction conditions of the process according to the invention, the prepolymerization reaction conditions when the prepolymerization is carried out at a reaction temperature of 20 to 80 ℃, preferably 0 to 60 ℃, more preferably 10 to 40 ℃, prepolymerization reaction The time is carried out for the prepolymerization reaction for a time to obtain 0.1 to 500 g, preferably 1 to 200 g, more preferably 2 to 40 g of polymer per gram of catalyst.

The present polymerization reaction is carried out at a temperature of 10 to 120 ° C, preferably 40 to 90 ° C, more preferably 50 to 70 ° C. The reaction time is selected in consideration of the catalytic activity so that the concentration of the (co) polymer in the reactor does not exceed 50% by weight, preferably 10 to 40%, more preferably 20 to 30%. Minutes to 20 hours, preferably 20 minutes to 10 hours, more preferably 30 minutes to 4 hours. Hydrogen may be used to control the molecular weight of the (co) polymer, and the molecular weight may be controlled by controlling the reaction temperature. The pressure in the polymerization reaction is carried out from its own vapor pressure in the reactor to 1000 bar, preferably 5 to 100 bar, more preferably 8 to 20 bar.

The steps for preparing a high-stereoregular butene-1 (co) polymer, respectively, are detailed according to the following examples (batch reactors). The preparation of polyolefins according to the invention is not limited to batch reactor types, but is a continuous batch reactor. (CSTR), tubular reactors, and other reactors can be applied without being limited to the type of reactor

Analysis and measurement method

¹³ Measurement of Stereoregularity Index (mmm%) by C NMR

A positive field Waltz16 in FT mode with a 10 wt% solution of polymer in C ₂ Cl ₄ D ₂ , having a spectral width of 10 KHz, pulse angle of 90 Hz, pulse repetition time of 16 seconds, and scan of 3600 The measurements were performed by recording the spectrum at a temperature of 120 ° C. with a DRX 500 MHz device operating at 125.7 MHz under decoupling. Then, the isotropic index was calculated according to:

Chemical of mobile computing and the five kinds of the polyolefin, measured from the polymerization mechanism ¹³ C NMR spectrum allocation (Carbon-13 NMR Spectral Assignment of Five Polyolefins Determined from the Chemical Shift Calculation and the Polymerization Mechanism) (T. Asakura and others, Macromolecules, 1991, 24 , 2334-2340).

Xylene Insolubility Index ( Xylene  Insolubles, X.I.) measurement

100 mL of xylene and 1 g of a sample in which 0.002 g of antioxidant (Igarnox 1010, Ciba, Switzerland) were dissolved were added to a flask and stirred while heating at about 130 ° C. for 40 minutes. Then, it was precipitated at 0 ° C. for about 1 hour and then further precipitated at room temperature for about 30 minutes. Using a filter paper (Whatman no.4 Filter Paper), the filtered filtrate was heated at about 130 ° C. for about 30 minutes until the solution evaporated, and then the mass change was measured to calculate XI. It was. At this time, the mass was measured using an analytical scale that can measure up to 4 digits after the decimal point, that is, 0.0001 g.

Melt Index Measurement

ASTM D 1238 Condition "E"

Gel Permeation Chromatography (GPC)  by MWD Measure

Flow rate 1 ml / min and operated at 135 ° C. using 1,2-dichlorobenzene (ODCB) as stabilized (stabilized by 0.1 vol. 2,6-di-t-butyl p-cresol (BHT)) Measurements were made using a Waters 150-C ALC / GPC system with a TSK column set (type GMHXL-HT). The sample was dissolved in ODCB by continuous stirring for 1 hour at a temperature of 140 ° C. The solution was filtered through a 0.45 μm Teflon membrane. The filtrate (concentration 300 μl injection volume 300 μl) was subjected to GPC. Monodisperse fractions of polystyrene (provided by Polymer Laboratories) were used as standard. Universal calibration of PB copolymers by using a linear combination of Mark-Houwink constants for PS (K = 7.11 10-5dl / g; α = 0.743) and PB (K = 1.18 10-4dl / g; α = 0.725) Was performed.

Hereinafter, the present invention will be described in more detail using examples.

Preparation Example: Preparation of Solid Catalyst Components

29.5 g of MgCl ₂ and 148.5 mL of 2-ethyl-hexanol were added to a 1 L glass reactor (Buchi) equipped with a magnetic stirrer, and the total volume of the reactor was adjusted to 650 mL by adding hexane, and the temperature of the reactor was increased to 130 ° C. It was then stirred for 3 hours at 200 rpm. After lowering the temperature of the reactor to 35 ° C, 178mL of TiCl ₄ was injected for 4 hours, and then 4.5mmol of diisobutylphthalate was added to the internal electron donor at the same temperature, and then the temperature of the reactor was increased to 110 ° C for 2 hours. Stir at 250 rpm. After cooling the temperature of the reactor to 35 ℃ to precipitate the solid component was filtered the supernatant and washed twice with hexane. After adding 150 mL of TiCl ₄ to the solid product thus obtained, the total volume of the reactor was changed to 500 mL with hexane, and then the reactor temperature was raised to 130 ° C. and stirred at 300 rpm for 2 hours. After stirring and lowering the reactor temperature to 80 ℃ and precipitated, the supernatant was filtered off, washed four times with hexane and dried under vacuum at 60 ℃. As a result of analysis of the resulting solid product, Ti was 1.7% by weight, Mg was 20.2% by weight, and internal electron donor (diaisobutyl phthalate) was 11.3% by weight.

Example  One: Butene Polymerization of -1 Polymer

First, purge the 3L stainless steel reactor equipped with a mechanical stirrer with argon at about 110 ° C, apply vacuum, and repeat the process of reducing the pressure to 0.95 atm based on atmospheric pressure to remove enough water or air that can act as a catalyst poison inside the reactor. It was.

After injecting 500 mL of purified decane into the reactor, the reaction mixture was lowered to about 5 ° C. or less from 50 ° C. while stirring. 0.1 g (total Ti amount of about 35 μmol) of the solid catalyst component prepared in the preparation example was added to the cocatalyst component, TIBA (Triisobutyl Aluminum) so that the Al / Ti ratio is 200 and stirred for about 3 to 5 minutes, and then Si Diisobutyldimethoxysilane was added as an external electron donor compound so that the ratio of / Ti was 5. After adding 0.4 mmol of the antistatic agent ATMER 163 (Ciba, Switzerland) to 30 g of hexane and diluting the total volume to 1 L, 0.1 g of the solid catalyst component prepared in Preparation Example was added to the reactor. Input. Thereafter, the reaction mixture was filled with N ₂ to a reaction pressure of 5 bar, and the polymerization reaction was started while injecting the butene-1 monomer.

The polymerization was carried out at a temperature of 50 ° C. and a pressure of 7 bar. After completion of the polymerization reaction, 10 mL of a hexane solution in which an antioxidant (Igarnox 1010, Ciba, Switzerland) was diluted to 5% by weight was added to terminate the polymerization reaction to obtain a butene-1 polymer.

Example  2: Butene Polymerization of -1 Polymer

The butene-1 polymer was obtained in the same manner as in Example 2 except that 0.8 mmol of the antistatic agent ATMER 163 was injected.

Example  3: Butene Polymerization of -1 Polymer

A butene-1 polymer was obtained in the same manner as in Example 1, except that 1.0 mmol of the antistatic agent ATMER 163 was injected and a diisobutyldimethoxysilane, which was an external electron donor compound, was not used.

Example  4: Butene Polymerization of -1 Polymer

A butene-1 polymer was obtained by the same method as Example 1 except that the polymerization temperature was performed at 40 ° C.

Example  5: Butene Polymerization of -1 Polymer

Except for ATMER 163, 0.174 g of Stadis 450 (the Associated Octel Company Limited, UK) was diluted with toluene and used at a concentration of 10% by weight, instead of ATMER 163. The process was carried out to obtain a butene-1 polymer.

Comparative example  One: Butene Polymerization of -1 Polymer

The butene-1 polymer was obtained in the same manner as in Example 1 except that no antistatic agent and an external electron donor were used.

Comparative example  2

A butene-1 polymer was obtained in the same manner as in Comparative Example 1 except that 0.2 mmol of diisobutyldimethoxysilane, which was an external electron donor compound, was used.

Comparative example  3

A butene-1 polymer was obtained in the same manner as in Comparative Example 1 except that 0.4 mmol of diisobutyldimethoxysilane, which was an external electron donor compound, was used.

Comparative example  4

A butene-1 polymer was obtained by the same method as Comparative Example 2 except that the polymerization temperature was performed at 40 ° C.

The reaction conditions performed in the examples and the comparative examples and the physical properties of the obtained butene-1 polymer are summarized in Table 1 below.

division Antistatic agent Antistatic Agent Usage External electron donor Si (mmol) Polymerization temperature (℃) Yield (g) MW (X10 ³ ) MWD X.I. (%) Stereoregularity index mmmm (%) Example 1 ATMER163 0.4 mmol 0.2 50 26 1580 6.06 95.5 90.4 Example 2 ATMER163 0.8 mmol 0.2 50 30 1514 6.17 96.3 92.1 Example 3 ATMER163 0.4 mmol 0 50 38 25.2 7.62 52.8 62.6 Example 4 ATMER163 1.0 mmol 0 50 40 794 5.96 73.2 59.3 Example 5 ATMER163 0.4 mmol 0.2 40 7.7 1393 7.85 93.2 86.8 Example 6 Stadis450 0.174 g 0 50 39 99.2 12.66 52.2 61.7 Comparative Example 1 - - 0 50 50 61.3 11.4 46.8 51.1 Comparative Example 2 - - 0.2 50 21 1701 7.07 88.3 79.6 Comparative Example 3 - - 0.2 40 6.6 1472 6.4 89.9 80.5

As shown in Table 1, by injecting an antistatic agent into the polymerization system according to the method of the present invention, the yield of polybutene-1, that is, the activity was improved, and furthermore, the XI index and the stereoregularity index were considered to be higher. Regularity was improved.

The present invention achieves the effect of introducing an antistatic agent into the process for preparing butene-1 (co) polymers, together with the improvement of the isotactic index (II) of the butene-1 (co) polymers, and also the polymerization activity. do.

Although described above with reference to a preferred embodiment of the present invention, those skilled in the art will be variously modified and changed within the scope of the invention without departing from the spirit and scope of the invention described in the claims below I can understand that you can.

Claims (15)

A method of producing a polyolefin by polymerizing an α-olefin monomer having 3 or more carbon atoms in the presence of an antistatic agent. The method of claim 1 wherein the polyolefin is polybutene-1 or polypropylene. The method of claim 1 wherein the antistatic agent is introduced directly into the reactor. The method of claim 1 wherein the antistatic agent is provided in the form contained in the catalyst. The method of claim 1, wherein some of the antistatic agent is added directly to the reactor and some is provided in the form contained in the catalyst. The method of claim 1 wherein the antistatic agent is selected from the group consisting of anionic surfactants, cationic surfactants, amphoteric surfactants, and nonionic surfactants. The method of claim 6, wherein the antistatic agent is a nonionic surfactant. The method of claim 1 wherein the polyolefin is prepared in the presence of a catalyst comprising a Ti compound and an internal electron donor. The method according to claim 8, wherein the catalyst is supported on MgCl ₂ . 9. The Ti compound according to claim 8, wherein the Ti compound is TiCl ₃ or Ti (OR) _n X _4-n , wherein R is C _1-18 alkyl, n is an integer from 0 to 3 and X is halogen. How to. The method of claim 8, wherein the internal electron donor is selected from the group consisting of esters, ethers, amines and ketones. The method of claim 11, wherein the internal electron donor is selected from the group consisting of benzoic acid or polycarboxylic acid of the C _{1 -18} alkyl, C _{1 -18} cycloalkyl, and C _{1 -18} aryl ester. The method of claim 8, further comprising alkylaluminum as a promoter. The method of claim 13 wherein the alkylaluminum is selected from the group consisting of triethylaluminum, triisobutylaluminum, tributylaluminum, trihexylaluminum, trioctylaluminum and mixtures thereof. A polyolefin prepared by the process according to any one of claims 1 to 14.