WO2002032295A2 - Method for post-processing styrene polymers - Google Patents

Method for post-processing styrene polymers Download PDF

Info

Publication number
WO2002032295A2
WO2002032295A2 PCT/EP2001/011998 EP0111998W WO0232295A2 WO 2002032295 A2 WO2002032295 A2 WO 2002032295A2 EP 0111998 W EP0111998 W EP 0111998W WO 0232295 A2 WO0232295 A2 WO 0232295A2
Authority
WO
WIPO (PCT)
Prior art keywords
styrene
rubber
polymer
auxiliary
impact
Prior art date
Application number
PCT/EP2001/011998
Other languages
German (de)
French (fr)
Other versions
WO2002032295A3 (en
Inventor
Christian Schade
Original Assignee
Basf Aktiengesellschaft
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Basf Aktiengesellschaft filed Critical Basf Aktiengesellschaft
Priority to AU1904202A priority Critical patent/AU1904202A/en
Publication of WO2002032295A2 publication Critical patent/WO2002032295A2/en
Publication of WO2002032295A3 publication Critical patent/WO2002032295A3/en

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
    • C08L51/00—Compositions of graft polymers in which the grafted component is obtained by reactions only involving carbon-to-carbon unsaturated bonds; Compositions of derivatives of such polymers
    • C08L51/003—Compositions of graft polymers in which the grafted component is obtained by reactions only involving carbon-to-carbon unsaturated bonds; Compositions of derivatives of such polymers grafted on to macromolecular compounds obtained by reactions only involving unsaturated carbon-to-carbon bonds
    • 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
    • C08F6/00—Post-polymerisation treatments
    • C08F6/001—Removal of residual monomers by physical means
    • C08F6/005—Removal of residual monomers by physical means from solid polymers
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
    • C08L25/00—Compositions of, homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by an aromatic carbocyclic ring; Compositions of derivatives of such polymers
    • C08L25/02—Homopolymers or copolymers of hydrocarbons
    • C08L25/04—Homopolymers or copolymers of styrene
    • C08L25/06—Polystyrene
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
    • C08L25/00—Compositions of, homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by an aromatic carbocyclic ring; Compositions of derivatives of such polymers
    • C08L25/02—Homopolymers or copolymers of hydrocarbons
    • C08L25/04—Homopolymers or copolymers of styrene
    • C08L25/08—Copolymers of styrene
    • C08L25/12—Copolymers of styrene with unsaturated nitriles
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
    • C08L25/00—Compositions of, homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by an aromatic carbocyclic ring; Compositions of derivatives of such polymers
    • C08L25/02—Homopolymers or copolymers of hydrocarbons
    • C08L25/04—Homopolymers or copolymers of styrene
    • C08L25/08—Copolymers of styrene
    • C08L25/14—Copolymers of styrene with unsaturated esters
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
    • C08L51/00—Compositions of graft polymers in which the grafted component is obtained by reactions only involving carbon-to-carbon unsaturated bonds; Compositions of derivatives of such polymers
    • C08L51/04—Compositions of graft polymers in which the grafted component is obtained by reactions only involving carbon-to-carbon unsaturated bonds; Compositions of derivatives of such polymers grafted on to rubbers
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
    • C08L53/00—Compositions of block copolymers containing at least one sequence of a polymer obtained by reactions only involving carbon-to-carbon unsaturated bonds; Compositions of derivatives of such polymers
    • C08L53/02—Compositions of block copolymers containing at least one sequence of a polymer obtained by reactions only involving carbon-to-carbon unsaturated bonds; Compositions of derivatives of such polymers of vinyl-aromatic monomers and conjugated dienes
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
    • C08L51/00—Compositions of graft polymers in which the grafted component is obtained by reactions only involving carbon-to-carbon unsaturated bonds; Compositions of derivatives of such polymers
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
    • C08L71/00—Compositions of polyethers obtained by reactions forming an ether link in the main chain; Compositions of derivatives of such polymers
    • C08L71/02—Polyalkylene oxides

Definitions

  • the invention relates to a process for the aftertreatment of styrene polymers by mixing liquid stripping agents into the melt of the styrene polymer and subsequent degassing.
  • This process is used on an industrial scale in the production of styrene polymers by bulk or solution polymerization for degassing residual monomers and solvent residues.
  • the preferred stripping agent is water, see e.g. US-A 3 773 740, EP-A 584 926 and the publications "Static Vacuum Degassing Apparatus in the Production of Quality Enhancement of Plastics" by J.E. Juvet and F.A. Streiff in "Vacuum in Research and Practice” (1998), No. 4, pages 285.293, WILEY-VCH-Verlag.
  • polymeric aids e.g. rubber-elastic toughness modifiers
  • two process principles are usually used in styrene polymers.
  • the rubbers are added on an industrial scale directly during the polymerization of the monomers; on the other hand, they can be incorporated into the finished polymers on an extruder, which, however, requires an additional work step.
  • the polymeric auxiliary is mixed into the melt of the styrene polymer as a dispersion or solution in a liquid stripping agent.
  • Styrene polymers are to be understood as: homopolystyrene (PS), impact-resistant modified polystyrene (HIPS) with polybutadiene rubber, styrene / butadiene block copolymers, copolymers of styrene with acrylonitrile (SAN), methyl methacrylate and maleic anhydride, and styrene / acrylonitrile copolymer which are modified with a polybutadiene or polyacrylate rubber (ABS or ASA).
  • PS homopolystyrene
  • HIPS impact-resistant modified polystyrene
  • SAN acrylonitrile
  • ABS polybutadiene or polyacrylate rubber
  • the preferred stripping agent is water, and C 1 -C 4 alcohols are also suitable, in principle also gases in the supercritical state, such as carbon dioxide, nitrogen and C 4 -C 6 alkanes.
  • Preferred polymeric auxiliaries are rubber-elastic impact modifiers, which are preferably used as an aqueous dispersion; According to the process of the invention, polyalkylene oxides, such as polyethylene glycol, which act as antistatic agents, can also be incorporated as aqueous solutions.
  • Emulsion graft polymers which consist of at least one hard phase and at least one soft phase and have a shell structure are particularly preferred.
  • the hard phase is formed primarily by monomers forming hard polymers, such as styrene, ⁇ -methylstyrene, methyl methacrylate, acrylonitrile, methacrylonitrile and maleic anhydride or mixtures thereof.
  • the outer phase is preferably a hard phase.
  • At least one of the inner phases is a soft phase, which is preferably formed from monomers forming soft polymers, such as butadiene, butyl acrylate or ethylhexyl acrylate.
  • These emulsion graft polymers preferably have a glass transition temperature of less than 0 ° C., in particular of less than -20 ° C.
  • those graft polymers are added whose hard phase is at least partially compatible with the polymer matrix of the melt.
  • the selected proportions of stripping agent and polymeric auxiliary depend on the content of residual monomers and solvent residues to be degassed in the styrene polymer, and on the other hand on the desired amount of polymeric auxiliary in the styrene polymer.
  • 0.5 to 20, in particular 1 to 10 parts by weight of the auxiliary dispersion or solution are preferably used per 100 parts by weight of styrene polymer.
  • the solids content of the dispersion or solution is preferably 20 to 80, in particular 30 to 65,% by weight.
  • a preferred graft consists of polybutadiene particles that contain occluded polystyrene cells, preferred emulsion grafts have a hard shell made of polystyrene or styrene copolymers and a soft core made of a polyacrylate rubber, polybutadiene or a butadiene / styrene copolymer.
  • the stripping process is carried out according to known, e.g. carried out in the methods described above.
  • the stripping agent is mixed into the polymer melt together with the polymeric auxiliary.
  • the stripping agent is then withdrawn again together with the volatile impurities in a degassing device from the polymer melt.
  • This process is preferably carried out continuously, preferably in static mixers or screw mixers, for example extruders. Heat is expediently added to the mixture or the components in order to facilitate the degassing process.
  • the degassing is preferably carried out under reduced pressure. Suitable degassing devices can be, for example, flash degassers, degassing extruders or thin-film evaporators.
  • auxiliaries and stripping agents are mixed into a polymer melt via a static mixer and the mixture is then expanded into a degassing pot operated under vacuum.
  • the stripping process efficiently removes residual styrene and other volatile compounds.
  • Polymers with a residual volatile compound content of less than 500, particularly preferably less than 300 ppm are preferably obtained.
  • the residual styrene content is preferably less than 200 ppm, very particularly preferably less than 160 ppm.
  • the rubber particles have an average particle size of 2.3 ⁇ m.
  • Latex 1 is a polymer dispersion with a soft phase made from butadiene (60%) and a hard phase made from styrene and acrylonitrile (80/20; 40%). The solids content of the aqueous dispersion was 39.6%.
  • Latex 2 is a polymer dispersion with a soft phase made from butyl acrylate and butanediol diacrylate (98/2; 60%) and a hard phase made from styrene (40%).
  • the solids content of the aqueous dispersion was 34.3%.
  • the rubber particles have an average particle size of 0.5 ⁇ m.
  • the styrene polymer granules are introduced into a twin-screw extruder (ZSK 30, W & P) with two filler necks and a degassing neck and melted at a temperature of around 240 ° C.
  • the polymer dispersion is pressed into this melt and mixed. Water, residual styrene and other volatile compounds are drawn off at a vacuum of 100 mbar through the expansion nozzle.

Abstract

The invention relates to a method for post-processing styrene polymers by admixing a preferably aqueous emulsion of a polymeric auxiliary agent to the melt of the styrene polymer and subsequently degassing it.

Description

Verfahren zur Nachbehandlung von StyrolpolymerisatenProcess for the aftertreatment of styrene polymers
Beschreibungdescription
Die Erfindung betrifft ein Verfahren zur Nachbehandlung von Styrolpolymerisaten durch Einmischen von flüssigen Stripmitteln in die Schmelze des Styrolpolymerisats und anschließendes Entgasen. Dieses Verfahren wird in großtechnischem Maßstab bei der Herstellung von Styrolpolymerisaten durch Masse- oder Lösungspolymerisation zur Entgasung von Restmonomeren und Lösungsmittel - resten eingesetzt. Bevorzugtes Stripmittel ist dabei Wasser, siehe z.B. US-A 3 773 740, EP-A 584 926 und die Veröffentlichungen "Statische Vakuumentgasungsapparate bei der Herstellung von Qualitätserhöhung von Kunststoffen" von J.E. Juvet und F.A. Streiff in "Vakuum in der Forschung und Praxis" (1998) , Nr. 4, Seiten 285.293, WILEY-VCH-Verlag .The invention relates to a process for the aftertreatment of styrene polymers by mixing liquid stripping agents into the melt of the styrene polymer and subsequent degassing. This process is used on an industrial scale in the production of styrene polymers by bulk or solution polymerization for degassing residual monomers and solvent residues. The preferred stripping agent is water, see e.g. US-A 3 773 740, EP-A 584 926 and the publications "Static Vacuum Degassing Apparatus in the Production of Quality Enhancement of Plastics" by J.E. Juvet and F.A. Streiff in "Vacuum in Research and Practice" (1998), No. 4, pages 285.293, WILEY-VCH-Verlag.
Zum Einarbeiten von polymeren Hilfsmitteln, wie z.B. kautschukelastischen Zähmodifikatoren, in Styrolpolymerisate werden üblicherweise zwei Verfahrensprinzipien angewandt. Zum einen werden in großtechnischem Maßstab die Kautschuke direkt bei der Polymerisation der Monomeren zugesetzt; zum anderen können sie in die fertigen Polymerisate auf einem Extruder eingearbeitet werden, was allerdings einen zusätzlichen Arbeits- schritt erfordert.For incorporating polymeric aids, e.g. rubber-elastic toughness modifiers, two process principles are usually used in styrene polymers. On the one hand, the rubbers are added on an industrial scale directly during the polymerization of the monomers; on the other hand, they can be incorporated into the finished polymers on an extruder, which, however, requires an additional work step.
Es bestand daher das Bedürfnis, ein kostengünstiges Verfahren zur Einarbeitung von Kautschuken in Styrolpolymerisate bereitzustellen, bei dem insbesondere bei kleineren Produktions -Serien eine problemlöse Umstellung der Art und Menge des Kautschuks möglich ist.There was therefore a need to provide an inexpensive process for incorporating rubbers into styrene polymers, in which a problem-free change in the type and amount of the rubber is possible, particularly in the case of smaller production series.
Es hat sich gezeigt, daß schlagfest modi iziertes Polystyrol mit bimodaler Teilchengrößenverteilung der Kautschukteilchen eine verbesserte Steifigkeit und einen höheren Glanz bei Erhalt der Schlagzähigkeit aufweist als solches mit unimodaler Teilchengrößenverteilung. Eine weitere Aufgabe der Erfindung bestand nun darin, ein elegantes Verfahren zur Herstellung derartiger Polymerisate zu entwickeln.It has been shown that impact-modified polystyrene with a bimodal particle size distribution of the rubber particles has an improved rigidity and a higher gloss while maintaining the impact resistance than that with a unimodal particle size distribution. Another object of the invention was to develop an elegant process for the preparation of such polymers.
Diese Aufgaben werden erfindungsgemäß dadurch gelöst, daß das poiymere Hilfsmittel als Dispersion oder Lösung in einem flüssigen Stripmittel in die Schmelze des Styrolpolymerisats eingemischt wird. Unter Styrolpolymerisate sind zu verstehen: Homopolystyrol (PS) , mit Polybutadienkautscb.uk schlagfest modifiziertes Polystyrol (HIPS) , Styrol/Butadien-Blockcopolymerisate, Copolymerisate des Styrols mit Acrylnitril (SAN), Methylmethacrylat und Malein- säureanhydrid, sowie Styrol/Acrylnitril-Copolymerisate, die mit einem Polybutadien- oder Polyacrylatkautschuk modifiziert sind (ABS bzw. ASA) .According to the invention, these objects are achieved in that the polymeric auxiliary is mixed into the melt of the styrene polymer as a dispersion or solution in a liquid stripping agent. Styrene polymers are to be understood as: homopolystyrene (PS), impact-resistant modified polystyrene (HIPS) with polybutadiene rubber, styrene / butadiene block copolymers, copolymers of styrene with acrylonitrile (SAN), methyl methacrylate and maleic anhydride, and styrene / acrylonitrile copolymer which are modified with a polybutadiene or polyacrylate rubber (ABS or ASA).
Bevorzugtes Stripmittel ist Wasser, daneben sind auch Cι-C - Alkohole geeignet, grundsätzlich auch Gase im überkritischen Zustand, wie Kohlendioxid, Stickstoff und C4-Cg-Alkane.The preferred stripping agent is water, and C 1 -C 4 alcohols are also suitable, in principle also gases in the supercritical state, such as carbon dioxide, nitrogen and C 4 -C 6 alkanes.
Bevorzugte polymere Hilfsmittel sind kautschukelastische Schlag- zägmodifikatoren, die vorzugsweise als wäßrige Dispersion ein- gesetzt werden; nach dem erfindungsgemäßen Verfahren können auch Polyalkylenoxide, wie Polyethylenglykol, die als Antistatika wirken, als wäßrige Lösungen eingearbeitet werden. Besonders bevorzugt sind Emulsionspfropfpolymerisate, die aus mindestens einer harten Phase und mindestens einer weichen Phase bestehen und einen Schalenaufbau besitzen. Die harte Phase wird vor allem von harte Polymere bildenden Monomeren, wie Styrol, α-Methylsty- rol, Methylmethacrylat, Acrylnitril, Methacrylnitril und Maleinsäureanhydrid oder Mischungen davon gebildet. Die äußere Phase ist bevorzugt eine harte Phase. Mindestens eine der inneren Pha- sen ist eine weiche Phase, die bevorzugt aus weiche Polymere bildenden Monomeren, wie Butadien, Butylacrylat oder Ethylhexyl- acrylat gebildet wird. Diese Emulsionspropfpolymerisate weisen vorzugsweise eine Glasübergangstemperatur von niedriger als 0°C, insbesondere von niedriger als -20°C auf. Bei einer besonders be- vorzugten Ausfύhrungsform der Erfindung werden solche Pfropfpolymerisate zugesetzt, deren Hartphase mit der Polymermatrix der Schmelze mindestens teilweise verträglich ist.Preferred polymeric auxiliaries are rubber-elastic impact modifiers, which are preferably used as an aqueous dispersion; According to the process of the invention, polyalkylene oxides, such as polyethylene glycol, which act as antistatic agents, can also be incorporated as aqueous solutions. Emulsion graft polymers which consist of at least one hard phase and at least one soft phase and have a shell structure are particularly preferred. The hard phase is formed primarily by monomers forming hard polymers, such as styrene, α-methylstyrene, methyl methacrylate, acrylonitrile, methacrylonitrile and maleic anhydride or mixtures thereof. The outer phase is preferably a hard phase. At least one of the inner phases is a soft phase, which is preferably formed from monomers forming soft polymers, such as butadiene, butyl acrylate or ethylhexyl acrylate. These emulsion graft polymers preferably have a glass transition temperature of less than 0 ° C., in particular of less than -20 ° C. In a particularly preferred embodiment of the invention, those graft polymers are added whose hard phase is at least partially compatible with the polymer matrix of the melt.
Die gewählten Mengenverhältnisse von Stripmittel und polymerem Hilfsmittel richten sich einmal nach dem Gehalt des Styrolpolymerisats an zu entgasenden Restmonomeren und Lösungsmittelresten, zum anderen nach der gewünschten Menge an polymerem Hilfsmittel im Styrolpolymerisat . Bevorzugt werden auf 100 Gew. -Teile Styrol- polymerisat 0,5 bis 20, insbesondere 1 bis 10 Gew. -Teile der Hilfsmittel-Dispersion bzw. -Lösung eingesetzt. Der Feststoffgehalt der Dispersion bzw. Lösung beträgt dabei vorzugsweise 20 bis 80, insbesondere 30 bis 65 Gew.-%.The selected proportions of stripping agent and polymeric auxiliary depend on the content of residual monomers and solvent residues to be degassed in the styrene polymer, and on the other hand on the desired amount of polymeric auxiliary in the styrene polymer. 0.5 to 20, in particular 1 to 10 parts by weight of the auxiliary dispersion or solution are preferably used per 100 parts by weight of styrene polymer. The solids content of the dispersion or solution is preferably 20 to 80, in particular 30 to 65,% by weight.
In einer bevorzugten Ausführungsform der Erfindung wird schlag - fest modfiziertes Polystyrol mit bimodaler Teilchengrößen-In a preferred embodiment of the invention, impact-modified polystyrene with bimodal particle sizes-
Verteilung der Kautschukteilchen und einem Reststyrolgehalt von weniger als 200 ppm dadurch hergestellt, daß man in geschmolzenes HIPS, welches einen Pfropfkautschuk in Form von Zellenteilchen mit einem mittleren Durchmesser von 1 bis 8 [ enthält, eine wäßrige Dispersion einarbeitet, die einen Emulsionspfropfkautschuk in Form von Kern/Schale-Teilchen mit einem mittleren Durchmesser von 0,1 bis 0,8 μm, enthält. Bevorzugter Pfropf autschuk besteht aus Polybutadienteilchen, die Polystyrolzellen okkludiert enthalten, bevorzugte Emulsionspfropf autschuke haben eine harte Hülle aus Polystyrol oder Styrolcopolymeren und einen weichen Kern aus einem Polyacrylatkautschuk, Polybutadien oder einem Butadien/Sty- rol -Copolymerisat.Distribution of the rubber particles and a residual styrene content of less than 200 ppm by making in melted HIPS, which contains a graft rubber in the form of cell particles with an average diameter of 1 to 8, incorporates an aqueous dispersion which contains an emulsion graft rubber in the form of core / shell particles with an average diameter of 0.1 to 0.8 μm, contains. A preferred graft consists of polybutadiene particles that contain occluded polystyrene cells, preferred emulsion grafts have a hard shell made of polystyrene or styrene copolymers and a soft core made of a polyacrylate rubber, polybutadiene or a butadiene / styrene copolymer.
Der Stripprozeß wird nach bekannten, z.B. in den oben genannten Literaturstellen beschriebenen Verfahren durchgeführt. Dazu wird das Stripmittel zusammen mit dem polymeren Hilfsmittel in die Polymerisatschmelze eingemischt. Das Stripmittel wird dann anschließend zusammen mit den flüchtigen Verunreinigungen in einer Entgasungseinrichtung der Polymerisat -Schmelze wieder entzogen. Bevorzugt wird dieser Prozeß kontinuierlich durchgeführt, vorzugsweise in statischen Mischern oder Schneckenmischern, bei- spielsweise Extrudern. Zweckmäßigerweise wird der Mischung oder den Komponenten Wärme zugeführt, um den Entgasungsprozeß zu erleichtern. Die Entgasung wird bevorzugt unter reduziertem Druck druchgeführt . Geeignete Entgasungseinrichtungen können beispielsweise Entspannungsentgaser, Entgasungsextruder oder Dünnschicht - Verdampfer sein.The stripping process is carried out according to known, e.g. carried out in the methods described above. For this purpose, the stripping agent is mixed into the polymer melt together with the polymeric auxiliary. The stripping agent is then withdrawn again together with the volatile impurities in a degassing device from the polymer melt. This process is preferably carried out continuously, preferably in static mixers or screw mixers, for example extruders. Heat is expediently added to the mixture or the components in order to facilitate the degassing process. The degassing is preferably carried out under reduced pressure. Suitable degassing devices can be, for example, flash degassers, degassing extruders or thin-film evaporators.
Besonders bevorzugt ist ein Prozeß, bei dem Hilfsmittel und Stripmittel einer Polymerschmelze über einen statischen Mischer zugemischt werden und die Mischung anschließend in einen unter Vakuum betriebenen Entgasungstopf entspannt wird.A process is particularly preferred in which auxiliaries and stripping agents are mixed into a polymer melt via a static mixer and the mixture is then expanded into a degassing pot operated under vacuum.
Durch den Stripprozeß werden Reststyrol und andere flüchtige Verbindungen effizient entfernt. Bevorzugt erhält man Polymerisate mit einem Restgehalt an flüchtigen Verbindungen von weniger als 500, besonders bevorzugt weniger als 300 ppm. Bei styrol- haltigen Polymerisaten beträgt der Restgehalt an Styrol bevorzugt weniger als 200 ppm, ganz besonders bevorzugt weniger als 160 ppm.The stripping process efficiently removes residual styrene and other volatile compounds. Polymers with a residual volatile compound content of less than 500, particularly preferably less than 300 ppm are preferably obtained. In the case of styrene-containing polymers, the residual styrene content is preferably less than 200 ppm, very particularly preferably less than 160 ppm.
Die in den Beispielen genannten Prozente beziehen sich auf das Gewicht .The percentages given in the examples relate to the weight.
BeispieleExamples
PS 1 ist ein Homopolystyrol mit einer mittleren Molmasse von Mw = 330 kg/mol und einer Breite der Verteilung von Mw/Mn = 3,1. PS 2 ist ein schlagzäg modifiziertes Polystyrol mit einem Matrix- Molekulargewicht von Mw = 185 kg/mol und einer Breite der Verteilung von Mw/Mn = 2.9. Es enthält 8 Gew. -% Polybutadien. Die Kautschukteilchen besitzen eine mittlere Teilchengröße von 2,3 μm.PS 1 is a homopolystyrene with an average molecular weight of M w = 330 kg / mol and a breadth of distribution of M w / M n = 3.1. PS 2 is an impact modified polystyrene with a matrix molecular weight of M w = 185 kg / mol and a width of distribution of M w / M n = 2.9. It contains 8% by weight of polybutadiene. The rubber particles have an average particle size of 2.3 μm.
Latex 1 ist eine Polymerdispersion mit einer Weichphase aus Butadien (60 %) und einer Hartphase aus Styrol und Acrylnitril (80/20; 40 %) . Der Feststoffgehalt der wäßrigen Dispersion betrug 39,6 %.Latex 1 is a polymer dispersion with a soft phase made from butadiene (60%) and a hard phase made from styrene and acrylonitrile (80/20; 40%). The solids content of the aqueous dispersion was 39.6%.
Latex 2 ist eine Polymerdispersion mit einer Weichphase aus Butylacrylat und Butandioldiacrylat (98/2; 60 %) und einer Hartphase aus Styrol (40 %) . Der Feststoffgehalt der wäßrigen Dispersion betrug 34,3 %. Die Kautschukteilchen besitzen eine mittlere Teilchengröße von 0,5 μm.Latex 2 is a polymer dispersion with a soft phase made from butyl acrylate and butanediol diacrylate (98/2; 60%) and a hard phase made from styrene (40%). The solids content of the aqueous dispersion was 34.3%. The rubber particles have an average particle size of 0.5 μm.
In einem Zweiwellextruder (ZSK 30, W & P) mit zwei Einfüllstutzen und einem Entgasungsstutzen werden die Styrolpolymerisat-Granu- late eingegeben und bei einer Temperatur von etwa 240°C aufge- schmolzen. In diese Schmelze wird die Polymerdispersion eingepreßt und vermischt. Durch den Entspannungstutzen werden Wasser, Reststyrol und andere flüchtige Verbindungen bei einem Unterdruck von 100 mbar abgesaugt.The styrene polymer granules are introduced into a twin-screw extruder (ZSK 30, W & P) with two filler necks and a degassing neck and melted at a temperature of around 240 ° C. The polymer dispersion is pressed into this melt and mixed. Water, residual styrene and other volatile compounds are drawn off at a vacuum of 100 mbar through the expansion nozzle.
Die Tabelle zeigt die Ergebnisse:The table shows the results:
Figure imgf000005_0001
Figure imgf000005_0001
Die Beispiele VI und V2 sind nicht erfindungsgemäß Examples VI and V2 are not according to the invention

Claims

Patentansprüche claims
1. Verfahren zur Nachbehandlung von Styrolpolymerisaten durch Einmischen von flüssigen Stripmitteln in die Schmelze des1. Process for the aftertreatment of styrene polymers by mixing liquid stripping agents into the melt of
Styrolpolymerisats und anschließendes Entgasen, dadurch gekennzeichnet, daß das Stripmittel ein polymeres Hilfsmittel zur Modifizierung des Styrolpolymerisats dispergiert oder gelöst enthält.Styrene polymer and subsequent degassing, characterized in that the stripping agent contains or disperses a polymeric auxiliary for modifying the styrene polymer.
2. Verfahren nach Anspruch 1, dadurch gekennzeichnet, daß das Styrolpolymerisat Polystyrol, schlagfest modifiziertes Polystyrol, ein Styrol/Butadien-Blockcopolymerisat, ein Copoly- merisat des Styrols mit Acrylnitril, Methylmethacrylat oder Maleinsäureanhydrid oder ein Styrol/Acrylnitril-Copolymerisat ist, welches mit einem Polybutadien- oder einem Polyacrylat- Kautschuk schlagfest modifiziert ist.2. The method according to claim 1, characterized in that the styrene polymer polystyrene, impact-resistant modified polystyrene, a styrene / butadiene block copolymer, a copolymer of styrene with acrylonitrile, methyl methacrylate or maleic anhydride or a styrene / acrylonitrile copolymer, which is with a Polybutadiene or a polyacrylate rubber is impact resistant modified.
3. Verfahren nach Anspruch 1, dadurch gekennzeichnet, daß das Stripmittel ein C1-C3 -Alkohol oder vorzugsweise Wasser ist.3. The method according to claim 1, characterized in that the stripping agent is a C 1 -C 3 alcohol or preferably water.
4. Verfahren nach Anspruch 1, dadurch gekennzeichnet, daß das polymere Hilfsmittel ein Kautschuk-elastischer Schlagzäh- modifikator oder ein Polyalkylenoxid ist.4. The method according to claim 1, characterized in that the polymeric auxiliary is a rubber-elastic impact modifier or a polyalkylene oxide.
5. Verfahren nach Anspruch 4, dadurch gekennzeichnet, daß das polymere Hilfsmittel ein Emulsionspfropfpolymerisat mit einer Glasübergangstemperatur von kleiner als 0°C von harte Polymere bildenden Monomeren auf ein Kautschuk-elastisches Poly- dien, Polydiencopolymer oder Polyacrylat ist.5. The method according to claim 4, characterized in that the polymeric auxiliary is an emulsion graft polymer with a glass transition temperature of less than 0 ° C of hard polymer-forming monomers on a rubber-elastic poly- diene, polydiene copolymer or polyacrylate.
6. Verfahren nach Anspruch 1, dadurch gekennzeichnet, daß auf 100 Gew. -Teile des Styrolpolymerisats 0,5 bis 20, vorzugsweise 1 bis 10 Gew. -Teile der Hilfsmittel -Dispersion bzw. -Lösung eingesetzt werden.6. The method according to claim 1, characterized in that 0.5 to 20, preferably 1 to 10 parts by weight of the auxiliary dispersion or solution are used per 100 parts by weight of the styrene polymer.
7. Verfahren nach Anspruch 1, dadurch gekennzeichnet, daß der Feststoffgehalt der Hilfsmittel -Dispersion bzw. -Lösung 20 bis 80 Gew.-% beträgt.7. The method according to claim 1, characterized in that the solids content of the auxiliary dispersion or solution is 20 to 80 wt .-%.
8. Verfahren zur Herstellung von schlagfest-modifiziertem Polystyrol (HIPS) mit bimodaler Teilchengrößenverteilung der Kautschukteilchen und einem Reststyrolgehalt von weniger als 200 ppm nach Anspruch 1, dadurch gekennzeichnet, daß man in geschmolzenes HIPS, welches einen Pfropfkautschuk in Form von Zellenteilchen mit einem mittleren Durchmesser von 1 bis 8 μm enthält, eine wäßrige Dispersion einarbeitet, die einen Emul- sionspfropf -Kautschuk in Form von Kern/Schale-Teilchen mit einem mittleren Durchmesser von 0,1 bis 0,8 μm enthält. 8. A process for the preparation of impact-modified polystyrene (HIPS) with a bimodal particle size distribution of the rubber particles and a residual styrene content of less than 200 ppm according to claim 1, characterized in that in melted HIPS, which is a graft rubber in the form of cell particles with an average diameter contains from 1 to 8 μm, incorporates an aqueous dispersion which contains an emulsion sion graft rubber in the form of core / shell particles with an average diameter of 0.1 to 0.8 microns.
PCT/EP2001/011998 2000-10-18 2001-10-17 Method for post-processing styrene polymers WO2002032295A2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AU1904202A AU1904202A (en) 2000-10-18 2001-10-17 Method for post-processing styrene polymers

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE10051602.5 2000-10-18
DE2000151602 DE10051602A1 (en) 2000-10-18 2000-10-18 Post-treatment of polystyrene to modify the impact strength comprises mixing a melt with a liquid stripping agent containing a dispersed or dissolved polymer aid and degassing

Publications (2)

Publication Number Publication Date
WO2002032295A2 true WO2002032295A2 (en) 2002-04-25
WO2002032295A3 WO2002032295A3 (en) 2002-07-04

Family

ID=7660189

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/EP2001/011998 WO2002032295A2 (en) 2000-10-18 2001-10-17 Method for post-processing styrene polymers

Country Status (3)

Country Link
AU (1) AU1904202A (en)
DE (1) DE10051602A1 (en)
WO (1) WO2002032295A2 (en)

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5899909A (en) 1994-08-30 1999-05-04 Medscand Medical Ab Surgical instrument for treating female urinary incontinence
US6273852B1 (en) 1999-06-09 2001-08-14 Ethicon, Inc. Surgical instrument and method for treating female urinary incontinence

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE4445141A1 (en) * 1994-12-17 1996-06-20 Basf Ag Process for the production of impact modified polystyrene molding compounds
ES2104481T3 (en) * 1995-03-27 1997-10-01 Basf Ag PROCEDURE FOR OBTAINING THERMOPLASTICS.
DE19713039A1 (en) * 1997-03-27 1998-10-01 Bayer Ag Process for the production of elastomer-modified thermoplastics
US5985997A (en) * 1997-05-23 1999-11-16 Chevron Chemical Company In situ process for making a bimodal HIPS having both high gloss and high impact strength
ES2198627T3 (en) * 1997-09-30 2004-02-01 Mitsui Chemicals, Inc. METHOD FOR REMOVING VOLATILE MATERIALS FROM A POLYMER COMPOSITION.

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5899909A (en) 1994-08-30 1999-05-04 Medscand Medical Ab Surgical instrument for treating female urinary incontinence
US6273852B1 (en) 1999-06-09 2001-08-14 Ethicon, Inc. Surgical instrument and method for treating female urinary incontinence

Also Published As

Publication number Publication date
DE10051602A1 (en) 2002-04-25
AU1904202A (en) 2002-04-29
WO2002032295A3 (en) 2002-07-04

Similar Documents

Publication Publication Date Title
DE69524336T3 (en) Transparent, rubber modified styrene resin and process for its preparation
EP0244856B1 (en) Thermoplastic moulding composition based on polycarbonate, asa and copolymers containing vinyl aromatics and an
DE3409066C2 (en)
EP0052732B1 (en) Thermoplastic moulding masses
DE60112213T2 (en) Oil resistant rubber modified polystyrene composition
DE102005001637A1 (en) Styrene-butadiene block copolymer blends for shrink films
DE1207621B (en) Thermoplastic compound for the production of impact-resistant molded bodies
EP0199846B1 (en) Fine particle dispersions of incompatible folymers in polymer matrices
EP1290075B1 (en) Stabilized thermoplastic moulding materials
DE1268833B (en) Thermoplastic compound for the production of impact-resistant molded bodies
DE69534119T2 (en) STYROL POLYMER RESINS WITH IMPROVED GLOSS AND IMPACT STRENGTH
EP0258741B1 (en) Thermoplastic moulding mass based on abs
DE4030351A1 (en) ABS-MOLDING MATERIAL
EP0219090A2 (en) Molding compounds on the basis of polycarbonate, SAN copolymers and one graft copolymer
WO2002032295A2 (en) Method for post-processing styrene polymers
DE3730886A1 (en) TRANSPARENT, IMPACT-RESISTANT THERMOPLASTIC MOLD, METHOD FOR THE PRODUCTION THEREOF AND THEIR USE
DE3140565A1 (en) Thermoplastic moulding composition
DE3106758A1 (en) METHOD FOR PRODUCING A MIXTURE FROM POLYCARBONATES AND POLYMERISATES CONTAINING STYRENE, USE OF THE MIXTURE AND MOLDED PARTS THEREOF
EP1017731B1 (en) Styrene polymer with bimodal molecular weight distribution
EP0071785B1 (en) Thermoplastic moulding masses
EP0261396B1 (en) Thermoplastic moulding mass based on abs
DE19743504A1 (en) High impact strength polystyrene for e.g. office equipment casings
DE102004013008A1 (en) Molding compositions comprising rubber finely dispersed in thermoplastic matrix, obtained by mixing organic solvent solutions of rubber and plastics having specific viscosity ratio
DE19951679A1 (en) Production of impact-resistant plastics, involves making crosslinked rubber from a conjugated diene-based monomer mixture, adding this to a styrene-based monomer mixture and polymerizing this mixture
DE10003511A1 (en) Process for the production of impact-resistant plastics

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A2

Designated state(s): AE AG AL AM AT AU AZ BA BB BG BR BY BZ CA CH CN CO CR CU CZ DE DK DM DZ EC EE ES FI GB GD GE GH GM HR HU ID IL IN IS JP KE KG KP KR KZ LC LK LR LS LT LU LV MA MD MG MK MN MW MX MZ NO NZ PH PL PT RO RU SD SE SG SI SK SL TJ TM TR TT TZ UA UG US UZ VN YU ZA ZW

AL Designated countries for regional patents

Kind code of ref document: A2

Designated state(s): GH GM KE LS MW MZ SD SL SZ TZ UG ZW AM AZ BY KG KZ MD RU TJ TM AT BE CH CY DE DK ES FI FR GB GR IE IT LU MC NL PT SE TR BF BJ CF CG CI CM GA GN GQ GW ML MR NE SN TD TG

AK Designated states

Kind code of ref document: A3

Designated state(s): AE AG AL AM AT AU AZ BA BB BG BR BY BZ CA CH CN CO CR CU CZ DE DK DM DZ EC EE ES FI GB GD GE GH GM HR HU ID IL IN IS JP KE KG KP KR KZ LC LK LR LS LT LU LV MA MD MG MK MN MW MX MZ NO NZ PH PL PT RO RU SD SE SG SI SK SL TJ TM TR TT TZ UA UG US UZ VN YU ZA ZW

AL Designated countries for regional patents

Kind code of ref document: A3

Designated state(s): GH GM KE LS MW MZ SD SL SZ TZ UG ZW AM AZ BY KG KZ MD RU TJ TM AT BE CH CY DE DK ES FI FR GB GR IE IT LU MC NL PT SE TR BF BJ CF CG CI CM GA GN GQ GW ML MR NE SN TD TG

121 Ep: the epo has been informed by wipo that ep was designated in this application
REG Reference to national code

Ref country code: DE

Ref legal event code: 8642

122 Ep: pct application non-entry in european phase
NENP Non-entry into the national phase

Ref country code: JP