EP1606336A1 - Procede pour produire des copolymeres organopolysiloxane et leur utilisation - Google Patents

Procede pour produire des copolymeres organopolysiloxane et leur utilisation

Info

Publication number
EP1606336A1
EP1606336A1 EP04719417A EP04719417A EP1606336A1 EP 1606336 A1 EP1606336 A1 EP 1606336A1 EP 04719417 A EP04719417 A EP 04719417A EP 04719417 A EP04719417 A EP 04719417A EP 1606336 A1 EP1606336 A1 EP 1606336A1
Authority
EP
European Patent Office
Prior art keywords
carbon atoms
diisocyanate
general formula
radical
sir
Prior art date
Legal status (The legal status 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 status listed.)
Withdrawn
Application number
EP04719417A
Other languages
German (de)
English (en)
Inventor
Oliver SCHÄFER
Sabine Delica
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Wacker Chemie AG
Original Assignee
Consortium fuer Elektrochemische Industrie GmbH
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 Consortium fuer Elektrochemische Industrie GmbH filed Critical Consortium fuer Elektrochemische Industrie GmbH
Publication of EP1606336A1 publication Critical patent/EP1606336A1/fr
Withdrawn legal-status Critical Current

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
    • C08G77/00—Macromolecular compounds obtained by reactions forming a linkage containing silicon with or without sulfur, nitrogen, oxygen or carbon in the main chain of the macromolecule
    • C08G77/42—Block-or graft-polymers containing polysiloxane sequences
    • C08G77/452—Block-or graft-polymers containing polysiloxane sequences containing nitrogen-containing sequences
    • C08G77/458—Block-or graft-polymers containing polysiloxane sequences containing nitrogen-containing sequences containing polyurethane sequences

Definitions

  • the invention relates to a process for the solvent-free production of organopolysiloxane / polyurea / polyurethane block copolymers and the use thereof.
  • polyurethanes and silicone elastomers are complementary in a wide range.
  • Polyurethanes are characterized by their excellent mechanical strength, elasticity and very good adhesion, abrasion resistance and simple processing by extrusion from the melt.
  • Silicone elastomers on the other hand, have excellent temperature, UV and weathering stability. They maintain their elastic properties at lower temperatures and therefore do not tend to become brittle. In addition, they have special water-repellent and non-stick surface properties.
  • urethane and silicone polymers make materials with good mechanical properties accessible ⁇ which are also characterized by processing options that are greatly simplified compared to silicones, but still have the positive properties of silicones.
  • the combination of the advantages of both systems can therefore lead to compounds with low glass transition temperatures, low surface energies, improved thermal and photochemical stabilities, low water absorption and physiologically inert materials.
  • the silicone and isocyanate polymer building blocks can be mixed in a wide range without problems. Due to the strong interactions of the hydrogen bonds between the urea units, these compounds have a defined softening point and thermoplastic materials are obtained.
  • thermoplastic materials are conceivable in many applications: in sealing compounds, adhesives, as a material for fibers, as a plastic additive e.g.
  • thermoplastic, thermoplastic elastomer, elastomer as packaging material for electronic components, in insulation or shielding materials, in cable sheathing, in antifouling materials, as an additive for cleaning, cleaning or care products, as an additive for personal care products, as a coating material for wood, paper and cardboard, as a mold release agent, as a biocompatible material in medical applications such as contact lenses, as a coating material for textile fibers or textile fabrics, as a coating material for natural substances such as Leather and furs, as material for membranes and as material for photoactive systems e.g. for lithographic processes, opt. Data backup or optical data transmission.
  • siloxane-urea copolymers which have high molecular weights and, as a result, favorable mechanical properties, such as high tear strength and elongation at break, and additionally have good processing properties, such as low viscosity at elevated temperatures and freedom from solvents.
  • good processing properties such as low viscosity at elevated temperatures and freedom from solvents.
  • the corresponding polymers are produced in solution, which is an expensive process for industrial use, since the solvent has to be removed in an additional process step.
  • European patent EP 0 822 951 describes a continuous reactor process for the solvent-free synthesis of such siloxane-urea block copolymers, in which the starting materials are reacted directly with one another.
  • organic diamines are additionally added in small amounts, which generates additional urea groups and thus increases the tensile strength of the corresponding polymers.
  • a disadvantage of this method is the sharp increase in the
  • Polyurea polymers are generally not processed by extrusion processes, since they have so many polar groups that bring the softening range of the material up to the decomposition temperatures of the urea bond.
  • RIM methods are usually used here, i.e. the polyreaction takes place in the mold.
  • the reaction of siloxane diamines with diisocyanates and organic bishydroxy compounds also gives thermoplastic products which have sufficient mechanical strength and can be processed in a temperature range below 200 ° C. without yellowing.
  • the organic dihydroxy compounds can also be used in proportions by weight of more than 20%. This shows that the softening temperatures no longer rise above a certain percentage, but remain almost constant, but the mechanical properties are improved even further.
  • the Ho et al. the process described is a two-stage process in which the second polymerization stage is carried out in dilute solution. For a technical process, this has the major disadvantage that the solvent then has to be removed again.
  • the object of the present invention was to provide a process for the continuous, solvent-free production of thermoplastic silicone-urea copolymers with improved mechanical properties and, at the same time, good extrudability in a temperature range from 80 to 190 ° C. Furthermore, the process should overcome the difficulty that the reaction of amines with isocyanates proceeds significantly faster than the reaction of alcohols with isocyanates, so that in a continuous process, a two-step reaction must be completed quantitatively during a certain residence time, in which it Segregation phenomena or viscosity increases in the polymer melt are overcome.
  • Dihydroxy compounds are also used in proportions by weight of more than 20%. It shows that the softening temperatures no longer exceed a certain percentage increase, but remain almost constant, but the mechanical properties are further improved.
  • the invention therefore relates to a process for the preparation of an organopolysiloxane / polyurea / polyurethane block copolymer (A) of the general formula (1):
  • R is a monovalent hydrocarbon radical with 1 to 20 carbon atoms, optionally substituted by fluorine or chlorine
  • X is an alkylene radical with 1 to 20 carbon atoms, in which methylene units which are not adjacent to one another can be replaced by groups -0-
  • R is hydrogen or an alkyl radical with 1 to 10
  • Y is a divalent hydrocarbon radical with 1 to 20 carbon atoms, optionally substituted by fluorine or chlorine,
  • D one optionally by fluorine, chlorine, C 1 -C 6 -alkyl or
  • Methylene units can be replaced by groups -0-, -COO-, -OCO-, or - OCOO-,
  • D 'a optionally by fluorine, chlorine, C] _- Cg-alkyl or
  • n is a number from 1 to 4000, a is a number of at least 1, b is a number larger 1, b 'is a number from 0 to 40, c is a number from 0 to 30 and d is a number greater than 0.
  • the aminoalkylpolydiorganosiloxane of the general formula (2) can be prepared by known methods such as equilibration reactions, hydrosilylation reactions or functionalization reactions with reactive aminosilanes.
  • R is preferably a monovalent, hydrocarbon radical having 1 to 6 carbon atoms, in particular unsubstituted. Particularly preferred radicals R are methyl, ethyl, vinyl and phenyl.
  • X is preferably an alkylene radical having 2 to 10 carbon atoms.
  • the alkylene radical X is preferably not interrupted.
  • the NR 'group preferably denotes an NH group.
  • Y is preferably a hydrocarbon radical having 3 to 13 carbon atoms, which is preferably unsubstituted.
  • Y is preferably an aralkylene, linear or cyclic alkylene radical.
  • D is preferably an alkylene radical having at least 2, in particular at least 4, carbon atoms and at most 12 carbon atoms.
  • D is likewise preferably a polyoxyalkylene radical, in particular polyoxyethylene radical or
  • the radical D is particularly preferably unsubstituted.
  • n preferably denotes a number of at least 3, in particular at least 25 and preferably at most 800, in particular at most 400, particularly preferably at most 250.
  • A is preferably a number of at most 50.
  • B is preferably a number of at least 5 but at most 100, in particular at most 50.
  • c preferably means a number of at most 10, in particular at most 5.
  • the polydiorganosiloxane-urea-urethane copolymer of the general formula (1) shows high molecular weights and good mechanical properties with good processing properties.
  • the chain extender of the general formula (6) can also be reacted with diisocyanate of the general formula (5) before the reaction in the second step.
  • water can also be used as a chain extender.
  • diisocyanates of the general formula (5) to be used are aliphatic compounds, such as isophorone diisocyanate, hexamethylene-1, 6-diisocyanate, tetramethylene-1, 4-diisocyanate and methylene dicyclohexy-4, 4 - diisocyanate or aromatic compounds such as methylene diphenyl 4 4 ⁇ - diisocyanate, 2, 4-toluene diisocyanate, 2, 5-toluenediisocyanate, 2, 6-toluenediisocyanate, m-phenylene diisocyanate, p-phenylene diisocyanate, m-xylene diisocyanate, tetramethyl-m-xylene diisocyan
  • Polyalkylenes or polyoxyalkylenes can also be copolymerized. These are preferably largely free of contamination from mono-, tri- or higher-functional polyoxyalkylenes.
  • polyether polyols, polytetramethylene diols, polyester polyols, polycaprolactone diols but also ⁇ , ⁇ -OH-terminated polyalkylenes based on polyvinyl acetate, polyvinyl acetate ethylene copolymers, polyvinyl chloride copolymer, polyisobutyl diols can be used.
  • Polyoxyalkyls are preferably used, particularly preferably polypropylene glycols.
  • Such compounds are commercially available as base materials, inter alia, for flexible polyurethane foams and for coating applications with molecular weights Mn of up to over 10,000.
  • base materials include the BAYCOLL® polyether polyols and polyester polyols from Bayer AG, Germany or the Acclaim® polyether polyols from Lyondell Inc., USA.
  • dihydroxy compounds within the meaning of the invention are also to be understood as bis-hydroxyalkyl silicones, such as those sold by the Goldschmidt company under the name Tegomer H-Si 2111, 2311 and 2711. These can include can be used to influence the softening ranges of the copolymers obtained in certain ranges.
  • copolymers of the general formula (1) described above are produced in a continuous process. It is essential that the selected polymer mixture is mixed optimally and homogeneously under the reaction conditions.
  • the production should generally take place in the absence of moisture and under protective gas, usually nitrogen or argon.
  • the low molecular weight components such as the isocyanate and the hydroxy compound are first metered into the reactor, a thorough mixing being obtained without the components reacting to a greater extent with one another in the absence of appropriate catalysts, i.e. they remain in a liquid state.
  • the aminosilicones and the catalyst are then metered in, and there is an immediate reaction between the amino groups and the isocyanate groups, which can be seen from a strong increase in viscosity.
  • the diol component is also already dissolved in the polymer due to the previous mixing with the isocyanate and can react in the further process with the isocyanate groups still present in the polymer with an increase in molecular weight.
  • the urea groups are first formed in one process step and then the urethane groups only afterwards, without additional solvent having to be removed.
  • the reaction is preferably carried out by adding a catalyst.
  • Suitable catalysts for the production are Dialkyltin compounds such as dibutyltin dilaurate, dibutyltin diacetate, or amines such as N, -dimethylcyclohexanamine, 2-dimethylaminoethanol, 4-dimethylaminopyridine.
  • Preferred applications of the polydiorganosiloxane-urea-urethane copolymers of the general formula (1) are uses as a constituent in adhesives and sealants, as a base material for thermoplastic elastomers such as, for example, cable sheaths, hoses, seals, keyboard mats, for membranes, such as selectively gas-permeable membranes , as additives in polymer blends, or for
  • Coating applications e.g. in non-stick coatings, fabric compatible coatings, flame retardant coatings and as biocompatible materials.
  • Example 1 (not according to the invention):
  • Examples 4 and 5-10 In a twin-shaft kneader from Collin, Ebersberg / Germany, with 6 heating zones, the first heating zone was under a nitrogen atmosphere
  • IPDI Isophorone diisocyanate
  • Dibutyltin dilaurate added.
  • the temperature profile of the heating zones was programmed as follows: Zone 1 30 ° C, Zone 2 100 ° C, Zone 3 160 ° C, Zone 4 180 ° C, Zone 5 160 ° C, Zone 6 125 ° C.
  • the speed was 50 rpm.
  • colorless polydimethylsiloxane-polyurea At the nozzle of the extruder, colorless polydimethylsiloxane-polyurea
  • Polyurethane block copolymer are removed, which were granulated after cooling.
  • Example 11 (not according to the invention): In a twin-shaft kneader from Collin, Ebersberg / Germany, with 6 heating zones, isophorone diisocyanate (IPDI) with a molecular weight of 222 g / mol at 1.09 g / min and Dytek TM was used in the first heating zone under nitrogen atmosphere A (methyl-diaminopentane) at 0.395 g / min and in the second heating zone aminopropyl-terminated silicone oil from Example 2 with a molecular weight of 3200 g / mol at 4 g / min.
  • IPDI isophorone diisocyanate
  • Dytek TM was used in the first heating zone under nitrogen atmosphere A (methyl-diaminopentane) at 0.395 g / min and in the second heating zone aminopropyl-terminated silicone oil from Example 2 with a molecular weight of 3200 g / mol at 4 g / min.
  • the temperature profile of the heating zones was programmed as follows: Zone 1 30 ° C, Zone 2 100 ° C, Zone 3 180 ° C, Zone 4 210 ° C, Zone 5 180 ° C, Zone 6 140 ° C.
  • the speed was 50 rpm.
  • Polydimethylsiloxane-polyurea block copolymers were partially removed at the extruder die and were granulated after cooling. However, a continuous process was not possible because the extruder kept clogging.
  • isophorone diisocyanate (IPDI) with a molecular weight was in the first heating zone under nitrogen atmosphere of 222 g / mol at 0.75 g / min and butanediol at 0.205 g / min and in the second heating zone the aminopropyl-terminated silicone oil from Example 3 with a molecular weight of 11000 g / mol at 13.5 g / min.
  • the aminopropyl-terminated silicone oil was mixed with 200 ppm of dibutyltin dilaurate.
  • the temperature profile of the heating zones was programmed as follows: Zone 1 30 ° C, Zone 2 100 ° C, Zone 3 160 ° C, Zone 4 180 ° C, Zone 5 160 ° C, Zone 6 125 ° C.
  • the speed was 50 rpm.
  • Colorless polydimethylsiloxane-polyurea-polyurethane block copolymer could be removed from the extruder die, which were granulated after cooling. It showed a softening point of 110 ° C and a tensile strength of 2.1 MPa.

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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)
  • Polyurethanes Or Polyureas (AREA)
  • Silicon Polymers (AREA)

Abstract

L'invention concerne un procédé pour la production continue et sans solvants de copolymères séquencés organopolysiloxane / polyurée / polyuréthane, par réaction de siloxanes à fonction amino avec des polyisocyanates et des composés polyhydroxy organiques. L'invention concerne également l'utilisation des copolymères séquencés organopolysiloxane / polyurée / polyuréthane produits selon ce procédé.
EP04719417A 2003-03-27 2004-03-11 Procede pour produire des copolymeres organopolysiloxane et leur utilisation Withdrawn EP1606336A1 (fr)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
DE10313938 2003-03-27
DE10313938A DE10313938A1 (de) 2003-03-27 2003-03-27 Verfahren zur Herstellung von Organopolysiloxane-Copolymeren und deren Verwendung
PCT/EP2004/002533 WO2004085517A1 (fr) 2003-03-27 2004-03-11 Procede pour produire des copolymeres organopolysiloxane et leur utilisation

Publications (1)

Publication Number Publication Date
EP1606336A1 true EP1606336A1 (fr) 2005-12-21

Family

ID=32980760

Family Applications (1)

Application Number Title Priority Date Filing Date
EP04719417A Withdrawn EP1606336A1 (fr) 2003-03-27 2004-03-11 Procede pour produire des copolymeres organopolysiloxane et leur utilisation

Country Status (6)

Country Link
US (1) US20060194937A1 (fr)
EP (1) EP1606336A1 (fr)
JP (1) JP2006521430A (fr)
CN (1) CN1764684A (fr)
DE (1) DE10313938A1 (fr)
WO (1) WO2004085517A1 (fr)

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DE102004041379A1 (de) * 2004-08-26 2006-03-02 Wacker-Chemie Gmbh Vernetzbare Siloxan-Harnstoff-Copolymere
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US20080318065A1 (en) 2007-06-22 2008-12-25 Sherman Audrey A Mixtures of polydiorganosiloxane polyamide-containing components and organic polymers
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CN109593197B (zh) * 2018-12-14 2021-01-05 东华大学 一种N-Si系纳米水凝胶阻燃剂及其制备和应用
CN110396172B (zh) * 2019-08-14 2022-04-08 上海鑫普新材料有限公司 一种用于轨道交通轨下垫块的弹性体及其制备方法
EP4132994B1 (fr) * 2020-04-06 2024-06-19 Setup Performance SAS Matériaux thermoplastiques à base de silicone pour impression 3d
CN112048067B (zh) * 2020-09-10 2022-04-22 广东宏昊化工有限公司 一种聚氨酯改性氨基聚醚硅油及其制备方法和应用
KR20230132471A (ko) * 2020-12-18 2023-09-15 셋업 퍼포먼스 에스에이에스 3d 프린팅용 실리콘 기반 열가소성 재료
CN112680167A (zh) * 2020-12-25 2021-04-20 成都硅宝科技股份有限公司 一种耐候性高强度聚氨酯密封胶及其制备方法
FR3149011A1 (fr) 2023-05-23 2024-11-29 Universite de Bordeaux Copolymères contenant des parties polydiméthylsiloxane (PDMS)

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Also Published As

Publication number Publication date
DE10313938A1 (de) 2004-10-14
WO2004085517A1 (fr) 2004-10-07
CN1764684A (zh) 2006-04-26
JP2006521430A (ja) 2006-09-21
US20060194937A1 (en) 2006-08-31

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