WO1996026228A1 - Statistische copolymerisate des propylens für schaumstoffe - Google Patents
Statistische copolymerisate des propylens für schaumstoffe Download PDFInfo
- Publication number
- WO1996026228A1 WO1996026228A1 PCT/EP1996/000576 EP9600576W WO9626228A1 WO 1996026228 A1 WO1996026228 A1 WO 1996026228A1 EP 9600576 W EP9600576 W EP 9600576W WO 9626228 A1 WO9626228 A1 WO 9626228A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- weight
- ethylene
- statistical copolymers
- propylene
- statistical
- Prior art date
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Classifications
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J9/00—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof
- C08J9/16—Making expandable particles
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
- C08F210/00—Copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond
- C08F210/04—Monomers containing three or four carbon atoms
- C08F210/06—Propene
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
- C08F210/00—Copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond
- C08F210/16—Copolymers of ethene with alpha-alkenes, e.g. EP rubbers
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
- C08L23/00—Compositions of homopolymers or copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond; Compositions of derivatives of such polymers
- C08L23/02—Compositions of homopolymers or copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond; Compositions of derivatives of such polymers not modified by chemical after-treatment
- C08L23/10—Homopolymers or copolymers of propene
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J2323/00—Characterised by the use of homopolymers or copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond; Derivatives of such polymers
- C08J2323/02—Characterised by the use of homopolymers or copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond; Derivatives of such polymers not modified by chemical after treatment
- C08J2323/10—Homopolymers or copolymers of propene
Definitions
- the present invention relates to statistical copolymers of propylene copolymerized with 0.1 to 20% by weight.
- [C 2 ] represents the weight fraction of the copolymerized ethylene and the proportion, based on% by weight, of isotactic triads [mm] or of isotactic pentads [mmmm], which is determined by ⁇ 3 C nuclear magnetic resonance spectroscopy, in The range of the following inequalities (Ha) or (Ilb) is:
- the present invention relates to a process for the preparation of the statistical copolymers, their use for the production of expanded polypropylene foam particles and the foam particles and moldings produced therefrom.
- the production of statistical copolymers of propylene with copolymerized ethylene by Ziegler-Natta polymerization has been described several times.
- the catalyst systems used include: Compounds of polyvalent titanium and magnesium compounds as titanium-containing solid component, furthermore an organic aluminum component and electron donor compounds, organic silicon compounds being mostly used (EP-A 45 977, EP-A 86 473,
- a reaction mixture of propylene and ethylene is polymerized, preferably from the gas phase, in conventional reactors.
- Statistical copolymers of this type are used, inter alia, used as films, fibers or moldings.
- the object of the present invention was therefore to remedy the disadvantages described and to provide improved statistical copolymers of propylene with copolymerized ethylene, which are particularly suitable for the production of foam particles. Furthermore, the object of the present invention also extends to the development of improved foam molded parts.
- the static copolymers of propylene according to the invention contain 0.1 to 20% by weight, in particular 0.5 to 10% by weight, of copolymerized ethylene and usually have a melt flow index of 0.1 to 100 g / 10 min. at 230 ° C and under a weight of 2.16 kg.
- the melt flow index corresponds to the amount of polymer which is pressed out within 10 minutes from the test device standardized according to DIN 53 735 at a temperature of 230 ° C. and under a weight of 2.16 kg.
- Preference is given to statistical copolymers of propylene which have a melt flow index of 0.5 to 50 g / 10 min. at
- Particularly preferred statistical copolymers of propylene contain 1.0 to 6.0% by weight and in particular 1.0 to 4.0% by weight of copolymerized ethylene.
- Such statistical copolymers can be carried out either batchwise or preferably continuously in the customary reactors used for the polymerization of propylene.
- Suitable reactors include continuously operated stirred kettles, it also being possible to use a number of several stirred kettles connected in series.
- the reactors contain a fixed bed made of finely divided polymer, which is usually kept in motion by stirring.
- the process can be carried out using the Ziegler-Natta catalysts customary in polymerization technology, both in the gas phase and in a solution or a slurry.
- This contain, in addition to a titanium-containing solid component, also cocatalysts.
- Organic aluminum compounds together with organic silicon compounds can be used as cocatalysts.
- Halides or alcoholates of tri- or tetravalent titanium are generally used as titanium compounds to produce the titanium-containing solid component, with the chlorides of titanium, in particular titanium tetrachloride, being preferred.
- the titanium-containing solid component advantageously contains a finely divided carrier, for which silicon and aluminum oxides, and aluminum silicates of the gross formula SiO 2 -aAl 2 3 3 , where a has a value of 0.001 to 2, in particular 0.01 to 0, 5 stands, have proven themselves.
- the carriers preferably used have a particle diameter of 0.1 to 1000 ⁇ m, in particular 10 to 300 ⁇ m, a pore volume of 0.1 to 10 cm 3 / g, in particular 1.0 to 5.0 cm 3 / g and a specific surface area of 10 to 1000 m / g, in particular of 100 to 500 m 2 / g.
- the titanium-containing solid component i.a. Compounds of magnesium used. Magnesium halides, magnesium alkyls and magnesium aryls, as well as magnesium alkoxy and magnesium arylox compounds are particularly suitable as such, magnesium dichloride, magnesium dibromide and magnesium di (C 1 -C 8 alkyl) compounds being used with preference.
- the titanium-containing solid component can also contain halogen, preferably chlorine or bromine.
- electron donor compounds for example mono- or polyfunctional carboxylic acids, carboxylic acid anhydrides and carboxylic acid esters, ketones, ethers, alcohols, lactones, and organophosphorus and organosilicon compounds are generally used in the preparation of the titanium-containing solid component.
- Preferred electron donor compounds within the titanium-containing solid component are phthalic acid derivatives of the general formula (V)
- X and Y are each chlorine or a C ⁇ to Cio alkoxy radical or together for oxygen.
- Particularly preferred electron donor compounds are phthalic acid esters, where X and Y are Ci-C ⁇ alkoxy, for example methoxy, ethoxy, propyloxy or butyloxy.
- Further preferred electron donor compounds within the titanium-containing solid component include diesters of 3- or 4-membered, optionally substituted cycloalkyl-1,2-dicarboxylic acids, and monoesters of optionally substituted benzophenone-2-carboxylic acids.
- the hydroxy compounds customary in esterification alcohols are used in these esters are, inter alia, C _, - to C_, s alkanols, C 5 - to C 7 alkanols -cycloalkyl which may carry themselves C ⁇ ⁇ C ⁇ o to _ alkyl groups, also phenols, naphthols and the -CC-alkyl derivatives of these compounds.
- the titanium-containing solid component can be prepared by methods known per se. Examples include: in EP-A 45 975, EP-A 86 473, EP-A 171 200, GB-A 2 111 066 and US-A 4 857 613.
- the titanium-containing solid component is used with cocatalysts as the Ziegler-Natta catalyst system.
- Organic aluminum compounds and organic silicon compounds can be used as cocatalysts.
- suitable aluminum components are also those compounds in which an alkyl group has been replaced by an alkoxy group or by a halogen atom, for example by chlorine or bromine.
- Trialkyl aluminum compounds whose alkyl groups each have 1 to 8 C atoms, for example trimethyl, triethyl or methyl diethyl aluminum, are preferably used.
- organosilicon compounds in particular of the general formula (VI), are also used as a further cocatalyst.
- R 1 is the same or different and a C ⁇ ⁇ to C 2 o-al yl group, a 5- to 7-membered cycloalkyl group, which in turn can carry a C ⁇ ⁇ to Cio-alkyl group, or a C ⁇ - to C 2 o - Aryl or arylalkyl group
- R 2 is the same or different and denotes a C 1 -C 20 -alkyl group and n represents the numbers 1, 2 or 3.
- Compounds in which R 1 is a C 1 -C 6 -alkyl group or a 5- to 7-membered cycloalkyl group, R 2 is a C ⁇ ⁇ to C alkyl group and n are the numbers 1 or 2.
- dimethoxydiisopropylsilane dimethoxyisopropylsec.butylsilane, dimethoxyisobutylisopropylsilane, dimethoxydiisobutylsilane, dimethoxydicyclopentylsilane and diethoxyisobutylisopropylsilane are to be emphasized.
- Catalyst systems are preferably used in which the atomic ratio between aluminum from the aluminum compound and titanium from the titanium-containing solid component is 1: 1 to 800: 1, in particular 2: 1 to 200: 1.
- the statistical copolymers of propylene according to the invention can be prepared with the aid of such catalyst systems. This is done by polymerizing a mixture of propylene and ethylene from the gas phase in one or more reactors connected in series.
- the statistical copolymers of propylene according to the invention are preferably obtainable by polymerization in a moving fixed bed in the absence of a liquid reaction medium from the gas phase at a temperature of 50 to 90 ° C., a pressure of 15 to 40 bar and an average residence time of Reaction mixture from 0.5 to 5 hours.
- a liquid reaction medium from the gas phase at a temperature of 50 to 90 ° C., a pressure of 15 to 40 bar and an average residence time of Reaction mixture from 0.5 to 5 hours.
- the statistical copolymers of propylene according to the invention include characterized in that their xylene-soluble portions (XL) of the following inequality (I)
- the xylene-soluble fractions in the statistical copolymer according to the invention are determined by extracting the milled starting materials in boiling xylene over a period of about 8 hours, then separating off the solvent by distillation and drying the residue at a pressure of 2 torr and a temperature of 80 ° C to constant weight.
- the statistical copolymers of ethylene according to the invention are characterized in that the proportion, based on% by weight of isotactic triads [mm] or of isotactic pentads [mmmm], which is determined by 13 C nuclear magnetic resonance spectroscopy, is in the range of the following inequalities ( Ha) or (Ilb) is:
- the isotactic triad ratio [mm] here means a ratio of neighboring propylene monomer units in which three neighboring monomers are continuously isotactically linked to one another.
- the isotactic pentad ratio [mmmm] corresponds to a structural unit consisting of five neighboring propylene monomers that are continuously isotactically linked.
- the isotactic triads [mm] or pentads [mmmm] are determined by means of 13 C nuclear magnetic resonance spectroscopy according to Y. Inoue, Y. Itabashi, R. Chujo and Y. Doi, Polymer, 1984, 2-2., Pages 1640-44 .
- Preferred statistical copolymers of propylene should also obey the following inequality (III) with regard to their rigidity [G modulus],
- the stiffness [G modulus] is specified in N / mm 2 and is determined in accordance with DIN 53 445.
- the statistical copolymers of propylene according to the invention are preferably also characterized in that their melting point [DSC], determined by the DSC method, corresponds to the following equation (IV)
- the statistical copolymers according to the invention are suitable for the production of films, fibers and moldings and, in particular, for the production of foam particles, which in turn can likewise be processed into moldings.
- the statistical copolymers according to the invention in particular have increased xylene-soluble fractions, which among other things has the consequence that their processing properties in the production of foams are significantly better than in conventional statistical copolymers.
- Another object of the invention are polypropylene foam particles with a diameter of 2 to 10 mm and a bulk density of 10 to 150, preferably 30 to 100 g-1 -1 , based on the statistical propylene copolymers according to the invention, and from them by sintering produced foam molded parts with improved properties.
- the foam particles are produced by the known impregnation foam or extrusion processes. In the impregnation foaming process, granulated propylene copolymer is suspended in water together with 2 to 40, preferably 5 to 30,% by weight of a volatile blowing agent.
- Suitable blowing agents are hydrocarbons, such as butane, pentane, cyclopentane, cyclohexane, gases such as carbon dioxide, noble gas, air or nitrogen, and mixtures of these blowing agents.
- the impregnation is preferably carried out in a stirred reactor at temperatures from 100 to 160 ° C. under a pressure of 10 to 100 bar with residence times between 30 and 180 minutes. It is then relaxed, the foam particles being formed.
- the xylene-soluble fraction and the isotactic fraction of the propylene copolymer practically do not change, so that the foam particle and molded parts produced from the copolymers also satisfy the inequalities I, Ha and Ilb.
- Foaming usual additives such as dyes, pigments, nucleating agents, stabilizers, flame retardants, lubricants and antistatic agents are added.
- the foam particles have a density of 10 to 150, preferably 30 to 100 g / l. Their particle diameter is usually 2 to 10 mm. They are predominantly closed cells with a cell number of preferably 1 to 500 cells per mm.
- the foam particles can be welded using conventional steam or hot air to give foam moldings which are used in the automotive and packaging industries.
- a gaseous mixture of propylene and ethylene was introduced into the gas phase reactor at a pressure of 23 bar and a temperature of 80 ° C., the ratio between the partial pressure of propylene and that of ethylene being 89: 1.
- This mixture was polymerized continuously with an average residence time of 3.0 hours with the aid of a Ziegler-Natta catalyst, 1.0 g of a titanium-containing solid component, 60 mmol of triethylaluminum and 1.2 mmol of dimethoxyisobutylisopropylsilane being used per hour Catalyst components were used.
- the molar ratio between the organic aluminum component and the organic silicon component was 66.7: 1.
- the titanium-containing solid component was produced by the following procedure:
- SiO 2 which has a particle diameter of 20 to 45 ⁇ m, a pore volume of
- the resulting titanium-containing solid component contained 3.1% by weight of titanium, 6.3% by weight of mangesiu and 24.8% by weight of chlorine.
- Example 1 was repeated under analogous conditions, but the molar ratio between the organic aluminum component and the organic silicon component was set to 92.3: 1.
- Example 1 was repeated under analogous conditions, but the molar ratio between the organic aluminum component and the organic silicon component was set to 100: 1.
- the powdery copolymers obtained in Examples 1 to 3 were first converted into small granules (grain weight 1.5 mg).
- a commercially available copolymer was also granulated for comparison. This has the following properties:
- Example 1 131.0 ° C 40.5 g / 1
- the foam particles were temporarily stored for 24 hours for drying and regeneration. Then they were filled pneumatically into a preheated molding chamber under dynamic pressure, the mold was let down to atmospheric pressure and then steamed for about 15 seconds. After the vapor pressure was released, the mold was cooled with water and air, then the molded part was removed. Table 3 shows the dynamic pressure which must be used at least to fill the mold with the foam particles, as well as an assessment of the molded part surface and the quality of the weld. + Means a low-gusset surface or good welding of the foam particles; - means a gusset-rich surface or poorer welding.
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- Chemical & Material Sciences (AREA)
- Health & Medical Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Medicinal Chemistry (AREA)
- Polymers & Plastics (AREA)
- Organic Chemistry (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Transition And Organic Metals Composition Catalysts For Addition Polymerization (AREA)
- Addition Polymer Or Copolymer, Post-Treatments, Or Chemical Modifications (AREA)
Abstract
Description
Claims
Priority Applications (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
EP96904058A EP0811024A1 (de) | 1995-02-23 | 1996-02-10 | Statistische copolymerisate des propylens für schaumstoffe |
JP8525352A JPH11500481A (ja) | 1995-02-23 | 1996-02-10 | 発泡体用のプロピレンランダム共重合体 |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE1995106286 DE19506286A1 (de) | 1995-02-23 | 1995-02-23 | Statistische Copolymerisate des Propylens für Schaumstoffe |
DE19506286.8 | 1995-02-23 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO1996026228A1 true WO1996026228A1 (de) | 1996-08-29 |
Family
ID=7754823
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/EP1996/000576 WO1996026228A1 (de) | 1995-02-23 | 1996-02-10 | Statistische copolymerisate des propylens für schaumstoffe |
Country Status (4)
Country | Link |
---|---|
EP (1) | EP0811024A1 (de) |
JP (1) | JPH11500481A (de) |
DE (1) | DE19506286A1 (de) |
WO (1) | WO1996026228A1 (de) |
Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4304890A (en) * | 1976-04-19 | 1981-12-08 | Chisso Corporation | Method for producing propylene copolymers using a catalyst activated prior to copolymerization |
EP0341724A1 (de) * | 1988-05-12 | 1989-11-15 | Union Carbide Corporation | Verfahren zur Herstellung statistischer Copolymere |
EP0550862A1 (de) * | 1992-01-09 | 1993-07-14 | BASF Aktiengesellschaft | Polyolefin-Schaumstoffe mit homogener Zellstruktur |
DE4242056A1 (de) * | 1992-12-14 | 1994-06-16 | Basf Ag | Copolymerisate des Propylens mit verringerter Weißbruchneigung |
EP0629631A2 (de) * | 1993-06-07 | 1994-12-21 | Mitsui Petrochemical Industries, Ltd. | Übergangsmetallverbindung, und diese enthaltender Polymerisationkatalysator |
-
1995
- 1995-02-23 DE DE1995106286 patent/DE19506286A1/de not_active Withdrawn
-
1996
- 1996-02-10 WO PCT/EP1996/000576 patent/WO1996026228A1/de not_active Application Discontinuation
- 1996-02-10 EP EP96904058A patent/EP0811024A1/de not_active Withdrawn
- 1996-02-10 JP JP8525352A patent/JPH11500481A/ja active Pending
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4304890A (en) * | 1976-04-19 | 1981-12-08 | Chisso Corporation | Method for producing propylene copolymers using a catalyst activated prior to copolymerization |
EP0341724A1 (de) * | 1988-05-12 | 1989-11-15 | Union Carbide Corporation | Verfahren zur Herstellung statistischer Copolymere |
EP0550862A1 (de) * | 1992-01-09 | 1993-07-14 | BASF Aktiengesellschaft | Polyolefin-Schaumstoffe mit homogener Zellstruktur |
DE4242056A1 (de) * | 1992-12-14 | 1994-06-16 | Basf Ag | Copolymerisate des Propylens mit verringerter Weißbruchneigung |
EP0629631A2 (de) * | 1993-06-07 | 1994-12-21 | Mitsui Petrochemical Industries, Ltd. | Übergangsmetallverbindung, und diese enthaltender Polymerisationkatalysator |
Also Published As
Publication number | Publication date |
---|---|
EP0811024A1 (de) | 1997-12-10 |
DE19506286A1 (de) | 1996-08-29 |
JPH11500481A (ja) | 1999-01-12 |
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