CN1093093A - vinyl polymerization or copolymerization catalyst - Google Patents
vinyl polymerization or copolymerization catalyst Download PDFInfo
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- CN1093093A CN1093093A CN 93103264 CN93103264A CN1093093A CN 1093093 A CN1093093 A CN 1093093A CN 93103264 CN93103264 CN 93103264 CN 93103264 A CN93103264 A CN 93103264A CN 1093093 A CN1093093 A CN 1093093A
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Abstract
The present invention is a kind of ethene (being total to) polymeric high activated catalyst and method for making thereof of being used for.Magnesium dichloride is dissolved in the mixture of liquid organophosphate and alcohols, form the magnesium chloride homogeneous solution, again in the presence of precipitation additive organic carboxyl acid acid anhydride, be added drop-wise in the liquid titaniferous compound, thereupon, solid sediment is separated out from solution, after filtration, the washing, obtain the main catalyst component A that the sundown powder is titaniferous, magnesium, chlorine, phosphorus, alkoxyl group, constitute polymerizing catalyst with promotor alkyl aluminum compound B component.Catalyst activity height of the present invention, polymer beads form are good, narrow diameter distribution, apparent density are big, are suitable for industrial production and use.
Description
The invention belongs to the ethylene rolymerization catalyst field
Conventional Ziegler-Natta catalyst is produced polyethylene need carry out aftertreatment removing the catalyzer ash content, and the service efficiency of titanium is not high, and every gram titanium can only be produced the polyethylene less than nine hectograms.After this, effective catalyst research occurred, made Ziegler-Natta catalyst obtain new development, early seventies begins industrialization, has brought dramatic change for ethene low-pressure polymerization technology, has reduced the polyethylene production cost widely and has produced investment.On technology, can save the polymkeric substance postprocessing working procedures, simplify technical process; But flexible polymericular weight, molecular weight distribution and side chain branch etc.; Can improve apparent density, the uniform particles degree of polymkeric substance.
The research of effective catalyst mainly concentrates on three aspects: the carrier of 1. choosing system super-active; The Primary Catalysts of the many dentates of 2. choosing system; 3. select fixture that the special organo-aluminium compound of greater activity is arranged.The method for making of efficient Primary Catalysts mainly contains common polishing, grind three kinds of pickling process and chemical reaction methods.There are shortcomings such as particle form is bad, size distribution is wide in the catalyzer that preceding two kinds of methods make; And the catalyzer that chemical reaction method makes is used for vinyl polymerization, can improve the particle form of polymkeric substance and improve apparent density, and many patents are arranged.This method is that solid magnesium compound such as magnesium dichloride are dissolved in earlier in some solvent, forms the magnesium chloride homogeneous solution, separates out solid sediment again in the presence of titanium tetrachloride, and this throw out is exactly a kind of solids containing titanium catalyzer.Employed solvent can be selected electron donor compounds such as ethers, alcohols, carboxylic-acid, ester class in the preparation.
Different companies, each is variant for its production technique, and relative merits are also respectively arranged.The technology that Mitsubishi changes into Industrial Co., Ltd's (spy opens clear 50-131887) is that the solid magnesium dichloride is dissolved in tetrahydrofuran (THF) (the being abbreviated as THF) solvent, forms MgCl
2-THF complex compound homogeneous solution is used TiCl then
4Handle, make Primary Catalysts, be used for vinyl polymerization and obtain having polyethylene, but activity of such catalysts is not high than high apparent density, every gram titanium obtain approximately 10 myriagrams polyethylene (polymerizing condition: 90 ℃, 1.0MPa).
The technology of Mitsui petrochemical industry Co., Ltd. (spy opens clear 57-158204) is that the solid magnesium dichloride is dissolved in organic alcohol compound such as the 2-Ethylhexyl Alcohol, separate out precipitation again, made Primary Catalysts, be used for vinyl polymerization, catalyst activity is higher, the polyethylene particle form is better, but in the catalyst preparation process, the solvent temperature height of magnesium compound, be 120 ℃, and need to use a large amount of solvents, therefore exist the solvent recuperation amount big, the aftertreatment technology complexity, shortcoming such as the polymerizer equipment utilization ratio is low.
The present invention adopts chemical reaction method to prepare effective catalyst, is conceived to improve Primary Catalysts, has overcome the shortcoming of above each company's catalyzer.The objective of the invention is to develop a kind of high titanium content, highly active ethylene rolymerization catalyst, be used for vinyl polymerization, resulting polymer beads form is good, narrow diameter distribution, and apparent density is big, and is convenient to industrial production and use.
Basic process of the present invention is that magnesium dichloride is dissolved in the mixture of liquid organophosphate and alcohols, form the transparent homogeneous solution of magnesium chloride, again in the presence of precipitation additive organic carboxyl acid acid anhydride, this drips of solution is added to temperature is-30～25 ℃, be preferably in-5～10 ℃ the compound titanium solution, dropwise, mixed solution is warming up to 50～120 ℃, thereupon, solids is separated out from mixed solution, and this suspension was stirred under this temperature 0.5～10 hour, filtered while hot, remove mother liquor, use 1 respectively, the 2-ethylene dichloride, the solids that hexane wash stays, made the pressed powder of sundown, be titaniferous main catalyst component A, its titaniferous amount is that 6～7%(is heavy), specific surface area is 150～250 meters
2/ gram.
The proportioning (mol ratio) of each main raw material that preparation A component is used is a magnesium dichloride: organophosphate: alcohols: organic carboxyl acid acid anhydride: titanium compound=1: (0.5～5): (0.05～2.0): (0.05～0.3): (5～20), preferably 1: (1～2): (0.1～1.0): (0.1～0.2): (10～18).Wherein organophosphate can be selected trimethyl phosphite 99, triethyl phosphate, tributyl phosphate, triphenylphosphate etc., is best with the tributyl phosphate; Alcohols can be selected C
1～C
8Straight chain alcohol or isomery alcohol as methyl alcohol, ethanol, propyl alcohol, Virahol, butanols, isopropylcarbinol, 2-Ethylhexyl Alcohol etc., are preferably selected ethanol; The organic carboxyl acid acid anhydride can be selected aliphatics polybasic acid anhydride, Tetra hydro Phthalic anhydride, Succinic anhydried etc., is best with the Tetra hydro Phthalic anhydride; Titanium compound is that to have general formula be TiX
n(OR)
4-nCompound, R is alkyl, X halogen, 0≤n≤4, as titanium tetrachloride, titanium tetrabromide, titanium tetra iodide, four titanium butoxide, purity titanium tetraethoxide and chlorinated alkoxy titanium etc., is best with the titanium tetrachloride.
Cocatalyst component B has general formula R
nAlX
3-nAlkylaluminium cpd, R is an alkyl in the formula, X is a halogen, mainly is chlorine, n=1～3 are selected triethyl aluminum, triisobutyl aluminium, aluminium diethyl monochloride, dichloro one aluminium triethyl, sesquialter chloroethyl aluminium etc. usually for use, preferably select triethyl aluminum, triisobutyl aluminium for use.
Constitute polymerizing catalyst of the present invention by main catalyst component A and cocatalyst component B, be used for vinyl polymerization or copolymerization.Catalyst consumption be in the control B component among aluminium and the component A mol ratio of titanium be 20～250, be preferably 50～150.
Adopting Ti-Al polymerizing catalyst of the present invention, under 85 ℃, 1.0MPa pressure, is that solvent carries out vinyl polymerization with the hexane, and polymerization 2 hours obtains the polyethylene of white.Draw as calculated, the activity of this polymerizing catalyst is greater than 90 myriagrams polyethylene/gram titanium, and the polymer yield of unit catalyzer is greater than 6 myriagrams polyethylene/gram catalyzer, and poly apparent density is at 0.37 gram per centimeter
3More than, median size is 320 μ, and wherein 140～630 μ account for more than 76%, and melting index (MI) is adjustable in 0.01～1000 scope.
Catalyzer of the present invention has following characteristics and advantage:
1, catalyzer of the present invention shows high reactivity.The result shows by the catalyst chemical compositional analysis, contains oxyethyl group (OC in the catalyzer
2H
5), and Ti-O key charateristic avsorption band, declaratives TiCl appear on the infrared spectra spectrogram
4Generated Ti(OR with ethanol synthesis)
nCl
4-nThe active centre of (n=1～4) form.Because (OC
2H
5) dentate stronger push away electronic effect, the electron density on the Ti of active centre is increased, weaken the Ti-C key, reduced the activation energy of displacement insertion reaction, impel the rate of chain growth of vinyl monomer on the titanium active centre to accelerate, activity is increased.
2, Ti content height in the catalyzer of the present invention, the polymer yield height of unit catalyzer, the polymer beads form is good, narrow diameter distribution, apparent density is big.
3, catalyzer of the present invention is used for vinyl polymerization, can adopt the hydrogen regulate polymer molecular weight, melting index is adjustable in/10 minutes scopes of 0.01～1000 gram, product grade and range of application have been enlarged, and when making melting index up to the polymkeric substance of 900 grams more than/10 minutes, catalyzer still has higher activity.
4, use alcohols in the catalyst preparation process of the present invention, reduced the viscosity of magnesium chloride solution, increased the stability of magnesium chloride solution, need not add inert solvent in addition, therefore improved the yield of throughput and minimizing solvent.
5, catalyst preparation process condition of the present invention is not harsh, as MgCl
2Solvent temperature is low, and the time is short, with TiCl
4The blended temperature does not require very low, and operation is simple, is convenient to industrial applying.
Embodiment 1
(1) preparation of catalyst component A
1, dissolving: fully clean the reaction flask that has agitator with high-purity nitrogen.Afterwards, in reaction flask, add 0.1 mole of phosphoric acid tri-n-butyl, under agitation, add 0.05 mole of solid water-free magnesium dichloride again, be warming up to 80 ℃ gradually, stirred 2 hours, the solid dissolving, shape solution is translucent; Treat that solution cooling back adds 0.03 mole of dehydrated alcohol, stir half an hour, be transparent homogeneous solution, add 0.0075 mole of Tetra hydro Phthalic anhydride again, when being warming up to 80 ℃, constant temperature 1 hour has obtained the magnesium chloride homogeneous solution.
2, throw out is separated out: the magnesium chloride solution that will newly obtain moves in the gauge line, and splashes in advance the 0.9 mole of TiCl that fills that is cooled to-5 ℃
4Another reaction flask in.Dropwise the back and heat up, thereupon, from solution, separate out solid sediment; Then, under 80 ℃, this solids suspension was stirred 3 hours.
3, washing solids: the reaction flask that will fill solids suspension moves in the nitrogen drying case, leaches mother liquor while hot; Use 1 then, the solids that the washing of 2-ethylene dichloride stays 3 times is used hexane wash 2 times again, logical nitrogen drying, and having obtained the sundown solids is main catalyst component A.Calculate by analysis and learn that the composition (weight %) of solids is a titanium 7.14, magnesium 12.86, chlorine 49.16, oxyethyl group 1.82, phosphorus 1.65; Specific surface area is 250 meters
2/ gram.
(2) polymerization
Fully cleaning volume with high-purity nitrogen is 2 liters stainless steel polymerization reaction kettle, uses hydrogen exchange nitrogen again.Afterwards, in reactor, add through 1.0 liters of exsiccant industrial hexane, promotor triethyl aluminum 1.0 mmoles and 0.0067 mmole (in titanium) (one) ingredient of solid catalyst A of making set by step; With reactor still temperature rise to 75 ℃, feed hydrogen, the control gauge pressure is 0.15MPa; Subsequently, feed ethene, ethylene pressure is controlled at the 0.75MPa(gauge pressure); The still temperature is transferred to 85 ℃, and polymerization 2 hours obtains white polyethylene, is weighed as 287.5 grams.Draw as calculated: activity of such catalysts is 91 myriagrams polyethylene/gram titanium; Polymer yield is 6.5 myriagrams polyethylene/gram catalyzer.Poly melting index (MI) is 0.56 gram/10 minutes; Poly apparent density is 0.37 gram per centimeter
3, median size is 320 μ, wherein 140～630 μ account for 78.8%(heavily).
Comparative example 1
Adopt with embodiment 1 identical operations condition and operation steps to prepare main catalyst component A and ethene polymers, different is not add ethanol in this process of the test.Test-results is listed table 1 in.Table 1 shows that titanium content almost reduces by 40% in the catalyzer, and activity of such catalysts reduces greatly, has only 31 myriagrams polyethylene/gram titanium, and apparent density also is lower than the data of embodiment 1.
Comparative example 2
Test conditions is identical with comparative example 1 with operation steps.Different is neither to add ethanol, does not also add Tetra hydro Phthalic anhydride.Test-results: reactant is gelatin liquid, can not get solid sediment.
Embodiment 2
Fully cleaning volume with high-purity nitrogen is 2 liters stainless steel polymerization reaction kettle, uses hydrogen exchange nitrogen again.Afterwards, in reactor, add dry 1.0 liters of industrial hexane, promotor triethyl aluminum 1.0 mmoles of crossing and ingredient of solid catalyst A 0.006 mmole (in titanium) that makes by embodiment 1.Heating makes still temperature rise to 60 ℃, feeds the 0.15MPa(gauge pressure) hydrogen, feed the 0.75MPa(gauge pressure subsequently) ethene-butylene
-1Gas mixture (contains butylene
-16.0 mole %); When the still temperature arrived 70 ℃, polymerization 2 hours made 190 gram ethylene copolymers.Calculate by analysis: catalyst activity is 66.2 myriagrams polyethylene/gram titanium, and multipolymer density is 0.9405 gram per centimeter
3, oligopolymer is few in the solvent hexane, and it is heavy to be about 0.03%().
Embodiment 3
The solids that employing is made by embodiment 1 is main catalyst component A, and other polymerizing conditions are also identical with embodiment 1 with method, and the add-on and the corresponding ethene input of control that change hydrogen are tested.Test-results obtains the polyethylene of many different molecular weights.Its result lists table 2 in.
Table 2
| Test number | Hydrogen add-on MPa | Ethene input MPa | Catalyst activity myriagram PE/ restrains Ti | Melting index MI gram/10 minutes |
| Embodiment 3-1 3-2 3-3 3-4 | 0.25 0.51 0.72 0.92 | 0.75 0.51 0.31 0.11 | 91 44.6 12.8 4.0 | 0.56 7.94 91.48 944.00 |
Claims (8)
1, a kind of Ziegler-Natta type heterogeneous catalyst composition that is used for vinyl polymerization or copolymerization, it is made up of main catalyst component A that contains magnesium, titanium, chlorine, phosphorus, alkoxyl group and alkylaluminium cpd cocatalyst component B, it is characterized in that:
(1) method for making of component A is under 20～100 ℃ of temperature, the solid magnesium dichloride is dissolved in the mixture of liquid organophosphate and alcohols, form the transparent homogeneous solution of magnesium chloride, again in the presence of precipitation additive organic carboxyl acid acid anhydride, this drips of solution is added to temperature in-30～25 ℃ the compound titanium solution, and this mixed solution is warmed up to 50～120 ℃, thereupon, solids is separated out from mixed solution, solids suspension after filtration, washing, the pressed powder that has obtained sundown is titaniferous main catalyst component A, after tested, calculate, titanium content is 6～7% (weights) in the Primary Catalysts, and specific surface area of catalyst is 150～250 meters
2/ gram;
(2) polymerizing catalyst that adopts the main catalyst component A that obtains by (1) and promotor component B to form, with the hexane is solvent, under 85 ℃, 1.0MPa pressure, carry out vinyl polymerization, polymerization obtained polyethylene powder after 2 hours, the activity of this polymerizing catalyst is greater than 90 myriagrams polyethylene/gram titanium, the polymer yield of unit catalyzer is greater than 6 myriagrams polyethylene/gram catalyzer, and poly apparent density is at 0.37 gram per centimeter
3More than, median size is 320 μ, and wherein 140～630 μ account for more than 76%, and melting index (MI) is adjustable in 0.01～1000 scope.
2, the method for making of ethylene rolymerization catalyst composition according to claim 1, the consumption that it is characterized in that main catalyst component A and cocatalyst component B be in the control B component among aluminium and the component A mol ratio of titanium be 20～250.
3, the method for making of main catalyst component A according to claim 1 is characterized in that the proportioning (mol ratio) of each main raw material is magnesium dichloride: organophosphate: alcohols: organic carboxyl acid acid anhydride: titanium compound=1: (0.5～5): (0.05～2.0): (0.05～0.3): (5～20).
4, cocatalyst component B according to claim 1 is characterized in that it is that to have general formula be R
nAlX
3-nAlkylaluminium cpd, R is an alkyl in the formula, X is a halogen, mainly is chlorine, n=1～3 are selected triethyl aluminum, triisobutyl aluminium, aluminium diethyl monochloride, dichloro one aluminium triethyl, sesquialter chloroethyl aluminium etc. usually for use.
5,, it is characterized in that the main raw material titanium compound is that to have general formula be TiX according to the method for making of claim 1 or 3 described main catalyst component A
n(OR)
4-nCompound, R is that alkyl, X are halogen, 0≤n≤4, as titanium tetrachloride, titanium tetrabromide, titanium tetra iodide, four titanium butoxide, purity titanium tetraethoxide and chlorinated alkoxy titanium etc.
6,, it is characterized in that the main raw material organophosphate can select trimethyl phosphite 99, triethyl phosphate, tributyl phosphate, triphenylphosphate etc. according to the method for making of claim 1 or 3 described main catalyst component A.
7,, it is characterized in that the main raw material alcohols can select C according to the method for making of claim 1 or 3 described main catalyst component A
1～C
8Straight chain alcohol or isomery alcohol are as methyl alcohol, ethanol, propyl alcohol, Virahol, butanols, isopropylcarbinol, 2-Ethylhexyl Alcohol etc.
8, according to the method for making of claim 1 or 3 described main catalyst component A, it is characterized in that precipitation additive organic carboxyl acid acid anhydride can select aliphatics polybasic acid anhydride and aromatic series polybasic acid anhydride, as MALEIC ANHYDRIDE, Tetra hydro Phthalic anhydride, Succinic anhydried etc.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 93103264 CN1034579C (en) | 1993-03-26 | 1993-03-26 | Catalyst for ethylene polymerization or copolymerization |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 93103264 CN1034579C (en) | 1993-03-26 | 1993-03-26 | Catalyst for ethylene polymerization or copolymerization |
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| Publication Number | Publication Date |
|---|---|
| CN1093093A true CN1093093A (en) | 1994-10-05 |
| CN1034579C CN1034579C (en) | 1997-04-16 |
Family
ID=4984554
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 93103264 Expired - Lifetime CN1034579C (en) | 1993-03-26 | 1993-03-26 | Catalyst for ethylene polymerization or copolymerization |
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| Country | Link |
|---|---|
| CN (1) | CN1034579C (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101280031B (en) * | 2007-04-06 | 2010-05-19 | 中国石油化工股份有限公司 | Catalyst system for preparing dual-peak or widely distributed polyethylene and its application |
| CN103360523A (en) * | 2012-04-03 | 2013-10-23 | 通用汽车环球科技运作有限责任公司 | Partly fluorinated polyolefins by Ziegler-Natta polymerization |
| CN104530272A (en) * | 2014-12-23 | 2015-04-22 | 中国科学院长春应用化学研究所 | Catalyst for polydiene synthesis and preparation method thereof |
| CN116715793A (en) * | 2023-06-12 | 2023-09-08 | 中国石化中原石油化工有限责任公司 | Preparation method of transparent polypropylene random copolymer |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100422226C (en) * | 2005-05-12 | 2008-10-01 | 北京燕化高新催化剂有限公司 | Preparation process of catalyst for ethylene polymerization |
-
1993
- 1993-03-26 CN CN 93103264 patent/CN1034579C/en not_active Expired - Lifetime
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101280031B (en) * | 2007-04-06 | 2010-05-19 | 中国石油化工股份有限公司 | Catalyst system for preparing dual-peak or widely distributed polyethylene and its application |
| CN103360523A (en) * | 2012-04-03 | 2013-10-23 | 通用汽车环球科技运作有限责任公司 | Partly fluorinated polyolefins by Ziegler-Natta polymerization |
| US9260542B2 (en) | 2012-04-03 | 2016-02-16 | GM Global Technology Operations LLC | Partly fluorinated polyolefins by Ziegler-Natta polymerization |
| CN104530272A (en) * | 2014-12-23 | 2015-04-22 | 中国科学院长春应用化学研究所 | Catalyst for polydiene synthesis and preparation method thereof |
| CN104530272B (en) * | 2014-12-23 | 2017-04-19 | 中国科学院长春应用化学研究所 | Catalyst for polydiene synthesis and preparation method thereof |
| CN116715793A (en) * | 2023-06-12 | 2023-09-08 | 中国石化中原石油化工有限责任公司 | Preparation method of transparent polypropylene random copolymer |
| CN116715793B (en) * | 2023-06-12 | 2024-06-11 | 中国石化中原石油化工有限责任公司 | Preparation method of transparent polypropylene random copolymer |
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| Publication number | Publication date |
|---|---|
| CN1034579C (en) | 1997-04-16 |
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