Method for preparing polysiloxane-polycarbonate block copolymers using at least one specialized condensation reactor

Abstract

The present invention relates to a multi-stage method for the continuous preparation of polysiloxane-polycarbonate block copolymers by polycondensation, characterized in that in a first stage an oligocarbonate and a hydroxyaryl-terminated polysiloxane are provided, and in a second stage at least one special condensation reactor is used, preferably exactly one special condensation reactor or exactly two special condensation reactors are used in the second stage. The method is also characterized in that a certain amount of a certain cocatalyst is added, which is added before the first special condensation reactor. The polysiloxane-polycarbonate block copolymers prepared by the method according to the invention are characterized by a high proportion of small polysiloxane domains, good mechanical properties, especially tough fracture behavior in the notch impact test according to ISO 7391 / ISO 180A, good processability, for example in injection molding or extrusion, and good flowability.

Description

[Technical field]

[0001] The present invention relates to a multi-stage method for the continuous production of polysiloxane-polycarbonate block copolymers by polycondensation, characterized in that in a first stage an oligocarbonate and a hydroxyaryl-terminated polysiloxane are provided, and in a second stage at least one special condensation reactor is used, preferably exactly one special condensation reactor or exactly two special condensation reactors arranged in series are used in the second stage. The method is further characterized in that a certain amount of a specific cocatalyst (described further below) is added, which is added upstream of the first special condensation reactor. The method according to the present invention preferably comprises the production of an oligocarbonate in a horizontal reactor in a first stage, which is reacted with a hydroxyaryl-terminated polysiloxane in a second stage to obtain a polysiloxane-polycarbonate block copolymer, also known as SiCoPC. The method is further characterized in that certain process parameters are observed in the reaction of the oligocarbonate with the hydroxyaryl-terminated polysiloxane in at least one special condensation reactor. The polysiloxane-polycarbonate block copolymers produced by the method according to the invention are characterized by a high proportion of small polysiloxane domains, good mechanical properties, in particular tough fracture behavior in the notched impact test according to ISO 7391 / ISO 180A, good processability, for example in injection molding or extrusion, and good flowability.

[0002] Here, the particular promoter is selected from one or more promoters based on alkali metals or alkaline earth metals.

[0003] In the context of the present invention, a high proportion of small polysiloxane domains results when the numerical proportion of polysiloxane domains ≧12 nm and <200 nm is greater than 99.0%, preferably greater than 99.2%, particularly preferably greater than 99.5%, very particularly preferably greater than 99.9%, in each case based on the total number of polysiloxane domains ≧12 nm.

[0004] To determine the size of the polysiloxane domains, polymer samples are cut at low temperatures and subjected to scanning electron microscopy examination as described in more detail below. In the context of the present invention, the diameter of a polysiloxane domain is understood here to mean the diameter of the circular equivalent projected area of ​​the cross section of the polysiloxane domain as seen by cutting. [Background technology]

[0005] It is known that polysiloxane-polycarbonate block copolymers show good properties in terms of low-temperature impact strength / low-temperature notched impact strength, chemical resistance and outdoor weathering resistance, as well as aging properties and fire resistance.Polysiloxane-polycarbonate block copolymers are superior in these properties to conventional polycarbonates, i.e. standard polycarbonates.In the context of the present invention, conventional polycarbonates or standard polycarbonates are understood to mean homopolycarbonates based on bisphenol-A as diphenol monomer units.

[0006] In the context of the present invention, the relative solution viscosity is determined in each case in dichloromethane at a concentration of 5 g / l at 25° C. using an Ubbelohde viscometer.

[0007] According to the prior art, polysiloxane-polycarbonate block copolymers are industrially produced starting from diphenol monomers and polydiorganosiloxanes by the so-called phase interface process using phosgene. The production of polysiloxane-polycarbonate block copolymers starting from diphenol monomers and polydiorganosiloxanes by the so-called melt transesterification process using diphenyl carbonate is also known from the prior art. However, this melt transesterification process has not been implemented on an industrial scale to produce polysiloxane-polycarbonate block copolymers.

[0008] In the case of the phase interface process, the production of polysiloxane-polycarbonate block copolymers by the prior art has the disadvantage of requiring starting materials with special handling requirements, such as phosgene. Furthermore, when an industrial plant configured to produce standard polycarbonate is used to produce polysiloxane-polycarbonate block copolymers in the melt transesterification process, the residence time of the reaction mixture for producing polysiloxane-polycarbonate block copolymers at high temperatures in the reactor becomes very long. This significantly increases the thermal stress on the polysiloxane-polycarbonate block copolymer, adversely affecting the properties of the polysiloxane-polycarbonate block copolymer.

[0009] The preparation of polysiloxane-polycarbonate block copolymers by a melt transesterification process is also described in US Pat. No. 5,399,623 or US Pat. No. 5,499,636. However, the reaction times disclosed therein are not economically viable for large-scale industrial processes. These documents do not contain any practical teachings on how the reaction time, and therefore the residence time, can be reduced.

[0010] Although Patent Document 2 also discloses that a small polysiloxane domain size of up to 15 nm can be achieved, the polysiloxane domain size that is evident only from the drawing is not useful for current demands, and furthermore, no method is disclosed that can obtain a high proportion of small polysiloxane domains.

[0011] Large polysiloxane domains in polysiloxane-polycarbonate block copolymers, i.e., polysiloxane domains larger than 200 nm, especially when present in large numbers, can adversely affect the aesthetic appearance and / or mechanical properties of molded articles made from polysiloxane-polycarbonate block copolymers. Large polysiloxane domains can lead to demixing of the polysiloxane phase from the polycarbonate phase in polysiloxane-polycarbonate block copolymers, which can manifest as a non-uniform surface structure of the polysiloxane-polycarbonate block copolymer, causing flow lines and striping, as well as undesirable optical interference, in injection molded molded articles made from polysiloxane-polycarbonate block copolymers. The aesthetic appearance of such molded articles is unsatisfactory, and such molded articles are no longer uniformly colorable, and therefore are not suitable for many commercial applications. Such polysiloxane-polycarbonate block copolymers are more difficult to process in injection molding because the large polysiloxane domains are susceptible to shear and can cause delamination in molded articles produced from such polysiloxane-polycarbonate block copolymers by injection molding, and as a result, often only very low injection speeds can be used, which is undesirable because of the long cycle times.

[0012] Furthermore, neither Patent Document 1 nor Patent Document 2 teaches any method by which the flowability of the resulting polysiloxane-polycarbonate block copolymer can be adjusted.

[0013] US Pat. No. 5,399,433 describes a two-stage process for producing polycarbonates using alkali metal-based or alkaline earth metal-based cocatalysts. US Pat. No. 5,399,433 further describes the reactor configurations for the individual reaction stages. It is particularly noted that the last reaction stage thus requires the use of a high-viscosity reactor, in particular a twin-screw extruder (particularly referred to as ZSK in US Pat. No. 5,399,433). However, it has surprisingly been found that such an arrangement is detrimental to the product properties / does not meet the requirements for economical production. It has been found that such a process cannot be scaled up to an industrial-scale process. Thus, as mentioned above, the melt transesterification process cannot be utilized in an industrial process.

[0014] In addition, US Pat. No. 5,399,633 does not disclose a method by which polysiloxane-polycarbonate block copolymers having a large proportion of small polysiloxane domains can be produced.

[0015] The skilled artisan will recognize what is understood by polysiloxane domains, which can be found, for example, in both "Polysiloxane Domains" by G. K. et al., "Plastic Polymers and Their Applications," Journal of Polymer Science, Vol. 13, No. 1, pp. 1171-1175, 2002 and "Polysiloxane Domains" by G. K. et al., "Plastic Polymers and Their Applications," Journal of Polymer Science, Vol.

[0016] Methods are known in principle that can reduce the proportion of large polysiloxane domains in polysiloxane-polycarbonate block copolymers. The addition of compatibilizers is described, for example, in US Pat. No. 5,399,433 / US Pat. No. 5,399,433. However, the compatibilizers described in US Pat. No. 5,399,433 / US Pat. No. 5,399,433 are very expensive and significantly increase the raw material costs of polysiloxane-polycarbonate block copolymers. Other compatibilizers are also disadvantageous because they are very expensive or decompose due to the high temperatures in the melt transesterification process or result in products with insufficient melt stability and cannot be used. [Prior art documents] [Patent documents]

[0017] [Patent Document 1] European Patent No. 0864599 [Patent Document 2] European Patent Application Publication No. 0770636 [Patent Document 3] European Patent Application Publication No. 0726285 [Patent Document 4] European Patent Application Publication No. 3719077 [Patent Document 5] International Publication No. 2020201178 [Non-patent literature]

[0018] [Non-Patent Document 1] "Structure to Property Relationship in Polycarbonate / Polydimethylsiloxane Copolymers", by Matthew R. Pixton, published in "Associacao Brasileira de Polimeros, Sao Paulo, SP (Brazil); [vp.]; 2005; 2 p; 8. Brazilian congress on polymers; 8. congresso brasileiro de polimeros; Aguas de Lindoia, SP (Brazil); 6-10 Nov 2005" [Non-Patent Document 2] "Structure to Property Relationship in Polycarbonate / Polydimethylsiloxane Copolymers", by Matthew R. Pixton, published in "ANTEC 2006, Annual Technical Conference, Charlotte, North Carolina, 7-11 May 2006, Conference Proceedings, pages 2655-2659" Summary of the Invention [Problem to be solved by the invention]

[0019] Starting from the above-mentioned prior art, it was therefore an object to overcome at least one of the disadvantages of the prior art. In particular, it was an object of the present invention to provide a method for the preparation of polysiloxane-polycarbonate block copolymers, which avoids starting materials with special handling requirements such as phosgene, can be carried out without solvent, can be scaled up to industrial scale and is economical to operate. Furthermore, it was an object to develop a melt transesterification process which is scalable and allows the preparation of polysiloxane-polycarbonate block copolymers with a high proportion of small polysiloxane domains, while at the same time having good flowability. Good flowability is advantageous during further processing of the polysiloxane-polycarbonate block copolymers in injection molding, since it allows the production of parts with complex shapes and thin wall thicknesses. Furthermore, it was an object to configure the method in such a way that it allows short residence times and is cost-effective. In this context, residence time means the time required for the preparation of the desired polysiloxane-polycarbonate block copolymers with the desired relative solution viscosity by incorporation of the polysiloxane component, and in the method according to the invention described below, the residence time corresponds to the reaction time.

[0020] The process must be carried out continuously. Furthermore, it was an aim to make it possible to avoid expensive compatibilizers.

[0021] In particular, it was an object to provide a process which is capable of being scaled up, i.e. starting from a laboratory process capable of discontinuously producing, for example, 1 g to 200 g, at most 1 kg, of polysiloxane-polycarbonate block copolymer per batch in a single laboratory plant, via a pilot-scale process capable of continuously producing, for example, 1 kg to 100 kg of polysiloxane-polycarbonate block copolymer per hour in a single pilot plant, to an industrial scale capable of continuously producing, in one production line, 100 kg / h to more than 500 kg / h of polysiloxane-polycarbonate block copolymer, preferably more than 1000 kg / h of polysiloxane-polycarbonate block copolymer.

[0022] It is understood here that in the polysiloxane-polycarbonate block copolymers, the numerical proportion of polysiloxane domains ≧12 nm and <200 nm is greater than 99.0%, preferably greater than 99.2%, particularly preferably greater than 99.5% and very particularly preferably greater than 99.9%, in each case based on the total number of polysiloxane domains ≧12 nm.

[0023] At the same time, the flowability must remain high. However, the flowability must not exceed values ​​that would result in a deterioration of the mechanical properties of the molded articles produced from the polysiloxane-polycarbonate block copolymers produced by the process according to the invention, in particular by injection molding. The relative solution viscosity can be regarded as a measure of the flowability. For this purpose, the relative solution viscosity of the polysiloxane-polycarbonate block copolymers produced by the process according to the invention, having a polysiloxane content of 2% by weight to 15% by weight, preferably 3% by weight to 10% by weight, particularly preferably 4% by weight to 8% by weight, should preferably be 1.24 to 1.38, preferably 1.26 to 1.36, particularly preferably 1.27 to 1.35. The polysiloxane-polycarbonate block copolymers produced according to the invention are easily processable, for example by injection molding or extrusion, with a relative solution viscosity in this range.

[0024] Very particularly preferably, the relative solution viscosity of the polysiloxane-polycarbonate block copolymers produced by the process according to the invention having a polysiloxane content of 4.5% to 5.5% by weight is 1.24 to 1.34, preferably 1.26 to 1.33, particularly preferably 1.27 to 1.32.

[0025] Here, the particularly preferred range is selected so that the combination of this polysiloxane content with the specified viscosity can achieve not only good mechanical properties but also good processability. As a result of the solution viscosity increasing especially at higher polysiloxane concentrations, the processability may not be optimal. However, by incorporating conventional polycarbonates with lower viscosities, it is possible to establish polysiloxane contents corresponding to the very particularly preferred range. This material is also characterized by good flowability and at the same time good mechanical properties. Those skilled in the art are also familiar with the mixing / formulation of such components, and in particular which viscosity of conventional polycarbonates needs to be used to achieve the corresponding viscosity.

[0026] Here too, in the polysiloxane-polycarbonate block copolymers, the numerical proportion of polysiloxane domains ≧12 nm and <200 nm should be more than 99.0%, preferably more than 99.2%, particularly preferably more than 99.5% and very particularly preferably more than 99.9%, in each case based on the total number of polysiloxane domains ≧12 nm.

[0027] The polysiloxane-polycarbonate block copolymers prepared according to the invention are very particularly easily processable, for example by injection molding or extrusion, at relative solution viscosities in the very particularly preferred range.

[0028] It is further particularly preferred that the polysiloxane-polycarbonate block copolymers produced by the method according to the invention exhibit a tough fracture behavior in the notched impact test according to ISO 7391 / ISO 180A down to -60°C. This is particularly true when the polysiloxane-polycarbonate block copolymers produced by the method according to the invention have a polysiloxane content of 4.5% to 5.5% by weight. It should be noted, however, that the same good mechanical properties can be achieved in this case, even with a higher polysiloxane content in the polysiloxane-polycarbonate block copolymers, by blending these polysiloxane-polycarbonate block copolymers with conventional polycarbonates according to the prior art. [Means for solving the problem]

[0029] These objects are surprisingly achieved by a method for preparing polysiloxane-polycarbonate block copolymers from oligocarbonates and hydroxyaryl-terminated polysiloxanes, characterized in that the method is a multi-stage method using a series of different reactors. These objects are surprisingly achieved in particular by a method in which oligocarbonates and hydroxyaryl-terminated polysiloxanes are provided in a first stage, and at least one special condensation reactor is used in a second stage, preferably exactly one special condensation reactor or exactly two special condensation reactors are used in the second stage, where a certain amount of a specific cocatalyst is added, and where this certain amount of this specific cocatalyst is added upstream of the first special condensation reactor. Wherein the specific cocatalyst is selected from one or more cocatalysts based on alkali metals or alkaline earth metals. In addition, specific process conditions are also observed. In the method according to the invention, in the first stage, the oligocarbonate is preferably prepared using a horizontal reactor.

[0030] In the context of the present invention, horizontal reactors, as disclosed, for example, in DE 4447422 or EP 0460466, which are preferably used in the first step of the method according to the invention, comprise a reaction space with at least one shaft, characterized in that the length of the reaction space is greater than the largest cross-sectional diameter of the reaction space. The length and cross-sectional diameter of the reaction space are mutually perpendicular spatial extents. Here, the longitudinal axis of the reaction space is horizontal with a deviation of at most ±0.2° as an inclination from the inlet of the reaction chamber to the outlet of the reaction chamber. The at least one shaft with which the reaction chamber is provided is preferably oriented parallel to the longitudinal axis of the reaction chamber. The reaction space of the horizontal reactor is preferably cylindrical if it comprises only one shaft. If the reaction space of the horizontal reactor comprises several shafts, in particular shafts parallel to each other and parallel to the longitudinal axis of the reaction space, it is preferably composed of mutually parallel interpenetrating cylindrical housings, as disclosed, for example, in EP 0460466.

[0031] It should be noted that, for the sake of clarity, in the context of the present invention, single screw extruders, twin screw extruders or multi-screw extruders are not considered horizontal reactors.

[0032] A special condensation reactor in the context of the present invention is characterized by: The reaction chamber comprises a shaft, the length of the reaction chamber in the direction of the axis of rotation being greater than the largest cross-sectional diameter of the reaction chamber. The length and cross-sectional diameter of the reaction chamber are mutually perpendicular spatial extents, where the front-rear axis of the reaction chamber is perpendicular with a maximum deviation of ±0.1° as an inclination to the vertical. The shaft with which the reaction chamber comprises is mounted parallel to the front-rear axis of the reaction chamber. At least one spreader, for example in the form of a wiper or wiper blade element or a spiral or screw, is fixed by press-fitting to the periphery of the shaft or configured as a component of the shaft, which, upon rotation of the shaft, (1) Rotates with the shaft. (2) oriented from the shaft toward a surface area within the reaction chamber; (3) Its outer edge, which is oriented towards the inner surface area of ​​the reaction chamber, wipes the inner surface area of ​​the reaction chamber during the rotation of the shaft, without touching the inner surface area of ​​the reaction chamber. Thus, there is a gap between the outer edge of the spreader, which is oriented towards the inner surface area of ​​the reaction chamber, and the inner surface area of ​​the reaction chamber. This wiping is preferably carried out so that the layer thickness of the reaction mixture spread on the inner surface area of ​​the reaction chamber is at least 0.5 mm and at most 20 mm, particularly preferably at least 1 mm and at most 10 mm, particularly preferably at least 1.5 mm and at most 6 mm. It is preferred that the special condensation reactor comprises a large number of spreaders, for example 2, 3, 4 or even more, for example 20 or more.

[0033] In the context of the present invention, "surface area in the reaction chamber" is understood to mean the surface area of ​​the specific condensation reactor to which the reaction mixture is applied. The surface area in the reaction chamber of each thin-film evaporator is a characteristic that is clearly specified by the manufacturer for the individual thin-film evaporator as a result of the construction and can be determined by simple measurements.

[0034] The reaction mixture can traverse the special condensation reactor from top to bottom and from bottom to top, preferably from top to bottom.When the reaction mixture traverses the special condensation reactor from top to bottom, it is at least partially gravity driven.When the reaction mixture traverses the special condensation reactor from bottom to top, the presence of a device that maintains this flow against gravity is required, such as a screw or spiral.

[0035] The special condensation reactor can be configured, for example, as a thin-film evaporator or an extruder.

[0036] A special condensation reactor in the context of the present invention, in proper operation, has a capacity of 20 kg / m based on the surface area within the reaction chamber. 2 h~100kg / m 2h of the reaction mixture into this special condensation reactor. This reaction mixture input into the special condensation reactor based on the surface area inside the reaction chamber is hereinafter referred to as the "application rate". When two or more special condensation reactors are used, the surface area used to calculate the application rate is the sum of the surface areas inside the reaction chambers of the special condensation reactors arranged in series, and the application rate of the surface area inside the reaction chamber by the reaction mixture is 20 kg / m 2 h~100kg / m 2 The value of h is maintained. This is true regardless of whether only one special condensation reactor or several special condensation reactors arranged in series are used.

[0037] It is preferred if the special condensation reactor is a thin-film evaporator.

[0038] In the context of the present invention, a thin-film evaporator is a vertically arranged device with an axially extending, rotationally symmetric, preferably cylindrical, reaction chamber, at the upper end of which a reaction mixture consisting of a polymer melt in the form of a molten dispersion and a liquid polysiloxane is fed, and at the lower end of which said mixture is discharged from the device in the form of a further reacted reaction mixture, and which is fitted with a rotor, i.e. a rotating shaft, on whose periphery at least two wiper blade elements, generally three, four or more wiper blade elements, are fixed. Here, each wiper blade element has an outer edge, which extends in the axial direction and is directed towards the inner surface area of ​​the axially extending rotationally symmetric reaction chamber, ensuring a constant surface renewal of the reaction mixture by spreading the reaction mixture over the inner peripheral edge of the axially extending rotationally symmetric reaction chamber. Here, the inner surface area of ​​the reaction chamber has the same geometric shape as the reaction chamber, i.e. the cylindrical reaction chamber also has a cylindrical inner surface area. Here, the wiper blade elements can be arranged parallel to the axial direction or at an action angle to the longitudinal axis.Thin-film evaporators which are in principle suitable for carrying out the process according to the invention are described, for example, in EP-A-3318311, EP-A-1792643, EP-A-0356419, DE-A-19535817, DE-A-102012103749, DE-A-2011493 or GDR-P-226778 or in the publication (1) "Platzer (ed.): Polymerization Kinetics and Technology, Advances in Chemistry; American Chemical Society: Washington, DC, 1973, pages 51 to 67: Fritz Widmer: Behaviour of Viscous Polymers during Solvent Stripping or Reaction in an Agitated Thin Film; Swiss Federal Institute of Technology, Zurich, Switzerland", where thin-film evaporators as disclosed in DE-A-19535817, GDR-A-226778 or EP-A-3318311 or as disclosed in FIG. 7, page 58 and FIG. 9, page 60 of (1) are particularly suitable for carrying out the method according to the invention. Further options for constructing thin-film evaporators are disclosed in the article "Scaleup of Agitated Thin-film Evaporators", William B. Glover, reprinted from Chemical Engineering, April 2004.

[0039] In the polycondensation of oligocarbonates and polysiloxanes to obtain polysiloxane-polycarbonate block copolymers, it is important to spread the melt of the reaction mixture over the surface area in the reaction chamber of the thin film evaporator, because the hydroxyl compounds formed during polycondensation, generally phenols, must be effectively removed by evaporation, thus requiring constant surface renewal.In such operations, which provide a large surface area in addition to good surface renewal, reactors are usually used, such as high-viscosity rotating disk reactors, as disclosed in DE-A-4447422 or EP-A-0460466, or other high-viscosity reactors, such as mesh basket reactors, as disclosed in WO-A-02085967.However, such high-viscosity reactors have the disadvantage of long residence times, especially in the production of polysiloxane-polycarbonate block copolymers.

[0040] Long residence times make the process of producing polysiloxane-polycarbonate block copolymers inflexible, so that when changing from one polysiloxane-polycarbonate block copolymer to be produced in a continuous process to another polysiloxane-polycarbonate block copolymer to be produced, long residence times generate a large amount of transition products, which are often not usable for further processing.Long residence times also have a negative effect on product quality, because long residence times increase thermal damage.

[0041] Furthermore, as already presented above, WO 2006 / 023666 describes the preferred use of a twin screw extruder (specifically referred to as ZSK in WO 2006 / 023666) in the final process section to ensure surface renewal. However, it has been found that the reactor combination described in WO 2006 / 0236666 is not optimal for product quality, the process cannot be scaled up to industrial scale, and / or product quality in terms of a high proportion of small polysiloxane domains is not achievable. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0042] (1) The object is in particular achieved in a first embodiment of the present invention by: A multi-step process for the continuous production of polysiloxane-polycarbonate block copolymers using exactly one specialized condensation reactor, comprising: The method comprises the following method steps: (1) providing an oligocarbonate having a relative solution viscosity of 1.08 to 1.22 and an OH group content of 1000 ppm to 2500 ppm; (2) the process step of combining the oligocarbonate from step (1) with the hydroxyaryl-terminated polysiloxane to provide a reaction mixture containing the oligocarbonate and the hydroxyaryl-terminated polysiloxane; (3) the process step of introducing the reaction mixture provided in step (2) containing the oligocarbonate and the hydroxylaryl-terminated polysiloxane into exactly one specific condensation reactor; wherein the specialized condensation reactor comprises a reaction chamber having a shaft with at least one spreader on its periphery, the spreader having an outer edge, the outer edge of the at least one spreader rotating at a specified distance from an outer wall of the reaction chamber; (4) a process step of reacting the reaction mixture from step (3) to obtain a polysiloxane-polycarbonate block copolymer; Wherein, the reaction mixture is conveyed from the inlet of the special condensation reactor to the outlet of the special condensation reactor; (5) discharging the polysiloxane-polycarbonate block copolymer obtained from step (4) from the special condensation reactor; It is characterized by: In step (4), exactly one specific condensation reactor is subjected to the following process conditions: (4.a) Pressure in the reaction chamber between 0.01 mbara and 10 mbara; (4.b) a temperature of the reaction mixture in the reaction chamber between 280° C. and 380° C., preferably between 290° C. and 370° C.; (4.c) a peripheral speed of at least one spreader at the periphery of the surface area of ​​the rotationally symmetric reaction chamber extending in the axial direction of the reactor of between 1 m / s and 5 m / s; was observed, The rate of application of the reaction mixture to the reaction chamber is 20 kg / m 2 h~100kg / m 2 h, Prior to introducing the reaction mixture provided in step (2) containing the oligocarbonate and the hydroxyaryl-terminated polysiloxane in accordance with step (3), the reaction mixture is added with 5×10 hydroxyaryl-terminated polysiloxane per kg of the hydroxyaryl-terminated polysiloxane, based on the weight of the hydroxyaryl-terminated polysiloxane. -7 mol~1×10 -3 mol amount of cocatalyst, Preferably, 1 x 10 per kg of hydroxyaryl-terminated polysiloxane -6 mol~5×10 -4 mol amount of cocatalyst, Particularly preferably, 5 x 10 per kg of hydroxyaryl-terminated polysiloxane -6 mol~2×10 -4 mol amount of cocatalyst, Very particularly preferably, 1 x 10 per kg of hydroxyaryl-terminated polysiloxane -5 mol~1×10 -4 mol amount of cocatalyst, Mix in The process wherein the cocatalyst is selected from one or more cocatalysts based on alkali metals and / or alkaline earth metals.

[0043] (2) Alternatively, the object is achieved in a second embodiment of the present invention by: A multi-stage process for the continuous production of polysiloxane-polycarbonate block copolymers using multiple special condensation reactors 1 arranged in series, comprising: The method comprises the following method steps: (1) providing an oligocarbonate having a relative solution viscosity of 1.08 to 1.22 and an OH group content of 1000 ppm to 2500 ppm; (2) the process step of combining the oligocarbonate from step (1) with the hydroxyaryl-terminated polysiloxane to provide a reaction mixture containing the oligocarbonate and the hydroxyaryl-terminated polysiloxane; (3) introducing the reaction mixture provided in step (2) containing the oligocarbonate and the hydroxylaryl-terminated polysiloxane into the first reactor of multiple specialized condensation reactors arranged in series; wherein each of the multiple specialized condensation reactors arranged in series comprises a reaction chamber having a shaft with at least one spreader on its periphery, the spreader having an outer edge, the outer edge of the at least one spreader rotating at a specified distance from an outer wall of the reaction chamber; (4) a process step of reacting the reaction mixture from step (3) to obtain a polysiloxane-polycarbonate block copolymer; The reaction mixture is conveyed from the inlet of the first special condensation reactor to the outlet of the last special condensation reactor of the multiple special condensation reactors arranged in series; (5) a process step of discharging the polysiloxane-polycarbonate block copolymer obtained from step (4) from the last special condensation reactor; It is characterized by: In step (4), the last reactor of a number of special condensation reactors arranged in series is subjected to the following process conditions: (4.a) Pressure in the reaction chamber between 0.01 mbara and 10 mbara; (4.b) a temperature of the reaction mixture in the reaction chamber between 280° C. and 380° C., preferably between 290° C. and 370° C.; (4.c) a peripheral speed of at least one spreader at the periphery of the surface area of ​​the rotationally symmetric reaction chamber extending in the axial direction of the reactor of between 1 m / s and 5 m / s; was observed, The rate of application of the reaction mixture to the reaction chamber is 20 kg / m 2 h~100kg / m 2 h, Prior to introducing the reaction mixture provided in step (2) containing the oligocarbonate and the hydroxyaryl-terminated polysiloxane in accordance with step (3), the reaction mixture is added with 5×10 hydroxyaryl-terminated polysiloxane per kg of the hydroxyaryl-terminated polysiloxane, based on the weight of the hydroxyaryl-terminated polysiloxane. -7 mol~1×10 -3 mol amount of cocatalyst, Preferably, 1 x 10 per kg of hydroxyaryl-terminated polysiloxane -6 mol~5×10 -4 mol amount of cocatalyst, Particularly preferably, 5 x 10 per kg of hydroxyaryl-terminated polysiloxane -6 mol~2×10 -4 mol amount of cocatalyst, Very particularly preferably, 1 x 10 per kg of hydroxyaryl-terminated polysiloxane -5 mol~1×10 -4 mol amount of cocatalyst, Mix in The process wherein the cocatalyst is selected from one or more cocatalysts based on alkali metals and / or alkaline earth metals.

[0044] In both the first embodiment of the process according to the invention and the second embodiment of the process according to the invention, when the cocatalyst is a sodium-based cocatalyst, the amount of cocatalyst added is in particular 1×10 per kg of hydroxyaryl-terminated polysiloxane. -6 mol~2×10 -4 mol of cocatalyst, very particularly 1×10 per kg of hydroxyaryl-terminated polysiloxane -5 mol~1×10 -4 mol of cocatalyst.

[0045] In both the first embodiment of the method according to the invention and the second embodiment of the method according to the invention, it applies that the layer thickness of the reaction mixture present on the inner surface area of ​​the reaction chamber is at least 0.5 mm and at most 20 mm, preferably at least 1 mm and at most 10 mm, particularly preferably at least 1.5 mm and at most 6 mm, very particularly preferably at least 3 mm and at most 4 mm.

[0046] In both the first embodiment of the method according to the invention and the second embodiment of the method according to the invention, it applies here that the thickness of the layer of the reaction mixture present on the surface area in the reaction chamber does not have to be identical in all respects, but rather the layer may comprise ridges and depressions, for example in the form of waves, i.e. areas of higher and lower layer thickness. These ridges and depressions in the layer of the reaction mixture are preferably spread by the movement of the rotor over the surface area in the reaction chamber. Such ridges and depressions are preferred because they improve the mass transfer and increase the surface area of ​​the layer of the reaction mixture, thus facilitating the removal of the hydroxyl compounds, generally phenols, formed during polycondensation.

[0047] In both the first embodiment of the method according to the invention and the second embodiment of the method according to the invention the following applies: The pressure measurement can be carried out, for example, using a WIKA IS-3 pressure sensor or an Endress+Hauser Cerabar pressure sensor, however, it is also possible to use other suitable prior art pressure sensors known to those skilled in the art.

[0048] In the context of the present invention, the term "mbara" denotes the unit for reporting absolute pressure in mbar, "mbar absolute."

[0049] The temperature of the reaction mixture can be measured, for example, by means of an L-type thermocouple or a Pt100 resistance thermometer, the measuring tip of which is immersed sufficiently deep in the reaction mixture. However, it is also possible to use other suitable prior art temperature measuring means known to the skilled artisan. The temperature measurement inside the thin-film evaporator can here be carried out in a manner known from EP 3 318 311 A1.

[0050] The rotational speed can be preferably measured via a conventional initiator / pulser on the rotor in a manner known to those skilled in the art. However, it is also possible to use other suitable conventional tachometers known to those skilled in the art. The surface renewal frequency is obtained by multiplying the rotational speed by the number of peripheral wiper blade elements.

[0051] In the second embodiment of the present invention, the multiple special condensation reactors arranged in series may be two or three or four or more special condensation reactors arranged in series.

[0052] According to the present invention, it is preferred that in the second embodiment of the present invention, the number of special condensation reactors arranged in series is exactly two.

[0053] In both the first embodiment of the process according to the invention and the second embodiment of the process according to the invention, it applies that the reaction mixture in process step (1) and the polysiloxane-polycarbonate block copolymer obtained on discharge from the last special condensation reactor of a number of special condensation reactors arranged in series, and the reaction mixture intermediately formed from the reaction mixture in process step (1) in the reaction to obtain the polysiloxane-polycarbonate block copolymer, are in molten form, where in the first embodiment of the process according to the invention, the only special condensation reactor can be considered as the last special condensation reactor.

[0054] The special condensation reactor that can be used according to the invention is preferably a thin film evaporator, characterized in that it comprises at least two wiper blade elements at its periphery that can rotate in the thin film evaporator. It is preferred that the thin film evaporator comprises three or more wiper blade elements, in particular three, four or more wiper blade elements, at its periphery that can rotate in the thin film evaporator.

[0055] At least a part of the axially extending rotationally symmetric inner surface area of ​​the axially extending rotationally symmetric reaction chamber of the thin film evaporator also serves as a heat transfer area. Heat can be supplied to the reaction chamber via the heat transfer area or heat can be removed from the reaction chamber via the heat transfer area. In the thin film evaporator, the proportion of the axially extending rotationally symmetric inner surface area of ​​the axially extending rotationally symmetric reaction chamber for applying the reaction mixture that serves as a heat transfer area is between 90% and 100%, preferably 100%. The respective heat transfer area of ​​the thin film evaporator is a feature that is clearly specified for the individual thin film evaporator by the manufacturer as a result of the construction and can be determined by simple measurements, but can also be clearly changed by the user, for example by partial or complete non-use of a heating device.

[0056] Here, in both the first embodiment of the method according to the invention and the second embodiment of the method according to the invention, the temperature of the heat transfer zone is between 280° C. and 350° C., preferably between 290° C. and 340° C., and any heat generated during the reaction of the reaction mixture in method step (4), for example by shearing of the reaction mixture, can be removed via the heat transfer zone, where the heat transfer zone may have a temperature profile or may have two or more temperature zones, or both.

[0057] In both the first embodiment of the process according to the invention and the second embodiment of the process according to the invention, the residence time of the reaction mixture in step (4) is preferably 6 minutes to 12 minutes, particularly preferably 7 minutes to 10 minutes.

[0058] In both the first embodiment of the process according to the invention and the second embodiment of the process according to the invention, the polysiloxane-polycarbonate block copolymers produced thereby can thus be obtained with short residence times.

[0059] According to the present invention, the term "intermediate polysiloxane-polycarbonate block copolymer", for example as formed intermediately in step (4), i.e. after introduction according to step (3) and before discharge in step (5), is used to distinguish it from the polysiloxane-polycarbonate block copolymer as obtained upon discharge from the special condensation reactor according to step (5).

[0060] Therefore, the term "intermediate" is used to clarify that the intermediate polysiloxane-polycarbonate block copolymer has a lower molecular weight than the polysiloxane-polycarbonate block copolymer. For this reason, the intermediate polysiloxane-polycarbonate block copolymer has a lower relative solution viscosity than the polysiloxane-polycarbonate block copolymer obtained at the outlet of the special condensation reactor according to step (5). The intermediate polysiloxane-polycarbonate block copolymer preferably has a relative solution viscosity of 1.20 to 1.27. It is clear to those skilled in the art that the use of oligocarbonates with lower relative solution viscosities generally also results in intermediate polysiloxane-polycarbonate block copolymers with lower relative solution viscosities. It is also clear to those skilled in the art that the intermediate polysiloxane-polycarbonate block copolymer also includes further condensed oligocarbonates with higher relative solution viscosities than the oligocarbonates used in step (1).

[0061] In a second embodiment of the method according to the invention the following applies: The reaction mixture for producing polysiloxane-polycarbonate block copolymers traverses continuously two series-arranged special condensation reactors, which are directly connected to each other via a pipe conduit. It is preferred that there are no further reactors between these two special condensation reactors. However, pumps or mixing elements, such as static mixers or dynamic mixers, can be used in the connection between the special condensation reactors. These pumps or these mixing elements are not considered as reactors, since the purpose of these pumps or these mixing elements is simply the mechanical processing of the materials. The second special condensation reactor may be followed by a further special condensation reactor or two or more further special condensation reactors, all arranged in series.

[0062] Both the polysiloxane-polycarbonate block copolymers obtained according to the first embodiment of the process according to the invention and the polysiloxane-polycarbonate block copolymers obtained according to the second embodiment of the process according to the invention have a high proportion of small polysiloxane domains, i.e. In both the polysiloxane-polycarbonate block copolymers obtainable according to the first embodiment of the process according to the invention and in the polysiloxane-polycarbonate block copolymers obtainable according to the second embodiment of the process according to the invention, the numerical proportion of polysiloxane domains ≧12 nm and <200 nm is in each case more than 99.0%, preferably more than 99.2%, particularly preferably more than 99.5% and very particularly preferably more than 99.9%, based on the total number of polysiloxane domains ≧12 nm.

[0063] Although the polysiloxane-polycarbonate block copolymers produced according to the present invention may have many polysiloxane domains having diameters less than 12 nm, these polysiloxane domains are not significant to the disadvantages discussed further above for a numerically high proportion of polysiloxane domains greater than or equal to 200 nm.

[0064] For this reason, both the polysiloxane-polycarbonate block copolymers obtained according to the first embodiment of the method according to the invention and the polysiloxane-polycarbonate block copolymers obtained according to the second embodiment of the method according to the invention are superior to prior art polysiloxane-polycarbonate block copolymers having a polysiloxane content of 2% to 15% by weight, in particular to prior art polysiloxane-polycarbonate block copolymers having a polysiloxane content of 3% to 10% by weight, in particular to prior art polysiloxane-polycarbonate block copolymers having a polysiloxane content of 4% to 8% by weight, where the polysiloxane content refers to the total weight of the polysiloxane-polycarbonate block copolymer. This is especially true when comparing the polysiloxane-polycarbonate block copolymers produced according to the invention with those produced by the melt transesterification process.

[0065] However, the polysiloxane-polycarbonate block copolymers prepared by the process according to the invention have a polysiloxane content of 4.5% to 5.5% by weight, which polysiloxane-polycarbonate block copolymers have a relative solution viscosity of 1.24 to 1.34, preferably 1.26 to 1.33, particularly preferably 1.27 to 1.325, where again the following applies: Both the polysiloxane-polycarbonate block copolymers obtained according to the first embodiment of the process according to the invention and the polysiloxane-polycarbonate block copolymers obtained according to the second embodiment of the process according to the invention have a high proportion of small polysiloxane domains, i.e. In both the polysiloxane-polycarbonate block copolymers obtainable according to the first embodiment of the process according to the invention and in the polysiloxane-polycarbonate block copolymers obtainable according to the second embodiment of the process according to the invention, the numerical proportion of polysiloxane domains ≧12 nm and <200 nm is in each case more than 99.0%, preferably more than 99.2%, particularly preferably more than 99.5% and very particularly preferably more than 99.7%, based on the total number of polysiloxane domains ≧12 nm.

[0066] The advantageous relative solution viscosity of the polysiloxane-polycarbonate block copolymers produced by the process according to the invention, which have a polysiloxane content in the very particularly preferred range of 4.5% to 5.5% by weight, means that the above-mentioned advantages of such polysiloxane-polycarbonate block copolymers are achieved to a particular extent, in particular such polysiloxane-polycarbonate block copolymers are particularly easily processable, for example by injection molding or extrusion.

[0067] Here, the very particularly preferred range is selected so that the polysiloxane-polycarbonate block copolymer with this polysiloxane content can achieve good mechanical properties and good processability at the same time as the specified relative solution viscosity.The increase in relative solution viscosity, especially at higher polysiloxane contents, can lead to non-optimal processability.However, by mixing in conventional polycarbonates with lower relative solution viscosity, it is possible to establish a polysiloxane content that corresponds to the very particularly preferred range.Such a mixture is again characterized by good flowability and good mechanical properties at the same time.

[0068] In further processing steps, the polysiloxane-polycarbonate block copolymer obtained by the method according to the invention may be blended with colorants and additives, and optionally with further polycarbonates.Those skilled in the art are also familiar with the mixing / blending of conventional polycarbonates with polysiloxane-polycarbonate block copolymers, and in particular with the relative solution viscosity that the conventional polycarbonate must have in order to achieve the desired relative solution viscosity of the mixture of conventional polycarbonates with polysiloxane-polycarbonate block copolymers.Therefore, the particularly preferred range of polysiloxane content is not limited, since the preferred combination of polysiloxane content and relative solution viscosity can be achieved by conventional blending of polysiloxane-polycarbonate block copolymers with conventional polycarbonates, especially when the polysiloxane content in the polysiloxane-polycarbonate block copolymer is high. However, it also applies when the relative solution viscosity values ​​of polysiloxane-polycarbonate block copolymers having a high polysiloxane content are excessive, such that the good processability of the polysiloxane-polycarbonate block copolymers still makes it impossible to reduce these high relative solution viscosity values ​​to reliable relative solution viscosity values ​​by blending with conventional polycarbonates having a lower relative solution viscosity.

[0069] The polysiloxane-polycarbonate block copolymers produced by the process according to the invention show robust fracture behavior down to -60°C in the notched impact test according to ISO 7391 / ISO 180A, even at low polysiloxane contents, i.e. less than 5% by weight.

[0070] 20 kg / m of reaction mixture into the reaction chamber 2 h~100kg / m 2It is surprising that the polysiloxane-polycarbonate block copolymers produced by the process according to the invention have such a high proportion of small polysiloxane domains and exhibit such good properties, since it was not expected that application rates as high as 10 ...

[0071] It is also surprising that such low amounts of cocatalyst addition can result in polysiloxane-polycarbonate block copolymers with such good characteristics and properties.

[0072] (3) In both the first embodiment of the method according to the invention and the second embodiment of the method according to the invention, the following applies: Already prior to step (2), the cocatalyst is added to the hydroxyaryl-terminated polysiloxane in a specified amount.

[0073] (4) Wherein, according to the present invention, in process step (4), the following process conditions are performed in a single special condensation reactor or in the last special condensation reactor of a number of special condensation reactors arranged in series: (4.a) The pressure in the reaction chamber of the special reaction reactor is 0.1 mbara to 6 mbara, preferably 0.2 mbara to 2 mbara; It is more preferable that the following is observed:

[0074] This more preferred embodiment of the method according to the invention is the fourth embodiment according to the first embodiment described above or the second embodiment described above.

[0075] (5) Here, according to the present invention, it is also preferred that the relative solution viscosity of the oligocarbonate provided in step (1) is 1.11 to 1.22, particularly preferably 1.13 to 1.20.

[0076] This very particularly preferred embodiment of the method according to the invention is the fifth embodiment according to the first embodiment described above or the second embodiment described above.

[0077] (6) Here, according to the present invention, it is further preferred that the polysiloxane content of both the polysiloxane-polycarbonate block copolymer produced according to the first embodiment of the method according to the present invention and the polysiloxane-polycarbonate block copolymer produced according to the second embodiment of the method according to the present invention is 2% by weight to 15% by weight, the polysiloxane content being based on the total weight of the polysiloxane-polycarbonate block copolymer.

[0078] This more preferred embodiment of the method according to the invention is the sixth embodiment according to the first embodiment described above or the second embodiment described above.

[0079] (7) Here, according to the present invention, it is particularly preferred that the polysiloxane content of the polysiloxane-polycarbonate block copolymer is 3% by weight to 10% by weight, and the polysiloxane content is based on the total weight of the polysiloxane-polycarbonate block copolymer.

[0080] This particularly preferred embodiment of the method according to the invention is the seventh embodiment according to the sixth embodiment described above.

[0081] (8) Here, according to the invention, it is very particularly preferred if the polysiloxane content of the polysiloxane-polycarbonate block copolymer is between 4% by weight and 8% by weight, said polysiloxane content being based on the total weight of the polysiloxane-polycarbonate block copolymer.

[0082] This very particularly preferred embodiment of the method according to the invention is the eighth embodiment according to the sixth embodiment described above.

[0083] (9) Here, according to the invention, it is very particularly preferred if the polysiloxane content of the polysiloxane-polycarbonate block copolymer is between 4.5% by weight and 5.5% by weight, said polysiloxane content being based on the total weight of the polysiloxane-polycarbonate block copolymer.

[0084] This very particularly preferred embodiment of the method according to the invention is the ninth embodiment according to the sixth embodiment described above.

[0085] (10) Here, according to the present invention, it is further preferred that the OH group content of the oligocarbonate provided in step (1) is 1200 ppm to 2300 ppm, particularly preferably 1400 ppm to 2200 ppm.

[0086] This more preferred embodiment of the method according to the invention is the tenth embodiment according to the first embodiment described above or the second embodiment described above.

[0087] (11) Here, according to the present invention, in step (1), it is more preferable to produce the reaction mixture containing an oligocarbonate having a relative solution viscosity of 1.08 to 1.22, preferably 1.11 to 1.22, and particularly preferably 1.13 to 1.20, and having an OH group content of 1000 ppm to 2500 ppm, preferably 1200 ppm to 2300 ppm, and particularly preferably 1400 ppm to 2200 ppm, and containing a hydroxyaryl-terminated polysiloxane, using a dynamic mixer and / or a static mixer.

[0088] This further preferred embodiment of the method according to the invention is the eleventh embodiment according to the first embodiment described above or the second embodiment described above.

[0089] (12) When the number of special condensation reactors arranged in series is at least two, in step (4) of the process, the following process conditions are satisfied: In the first special condensation reactor, (4.1.a) Pressure in the reaction chamber between 1 mbara and 10 mbara; (4.1.b) the temperature of the reaction mixture in the reaction chamber between 270°C and 350°C; (4.1.c) a surface renewal frequency of the reaction mixture between 10 Hz and 30 Hz; In the final special condensation reactor, (4.2.a) a pressure in the reaction chamber of 0.1 mbara to 3 mbara, preferably 0.2 mbara to 2 mbara; (4.2.b) the temperature of the reaction mixture in the reaction chamber between 280°C and 370°C; (4.2.c) a surface renewal frequency of the reaction mixture between 10 Hz and 30 Hz; is preferably observed, The reaction mixture application rate to the reaction chamber was 30 kg / m 2 h~60kg / m 2 h.

[0090] This embodiment of the method according to the invention is a twelfth embodiment according to the second embodiment described above.

[0091] It applies here that the layer thickness of the reaction mixture present on the inner surface area of ​​the reaction chamber is at least 1 mm and at most 10 mm, particularly preferably at least 1.5 mm and at most 6 mm, very particularly preferably at least 3 mm and at most 4 mm.

[0092] The present invention has the following features: the polysiloxane content is 2% to 15% by weight based on the total weight of the polysiloxane-polycarbonate block copolymer; the numerical proportion of polysiloxane domains ≥ 12 nm and < 200 nm is in each case greater than 99.0%, preferably greater than 99.2%, particularly preferably greater than 99.5% and very particularly preferably greater than 99.9%, based on the total number of polysiloxane domains ≥ 12 nm, The present invention further provides a polysiloxane-polycarbonate block copolymer comprising:

[0093] Here, the polysiloxane-polycarbonate block copolymer has a relative solution viscosity of 1.24 to 1.34, preferably 1.26 to 1.33, and particularly preferably 1.27 to 1.325.

[0094] The present invention has the following features: the polysiloxane content is 3% to 10% by weight based on the total weight of the polysiloxane-polycarbonate block copolymer; the numerical proportion of polysiloxane domains ≥ 12 nm and < 200 nm is in each case greater than 99.0%, preferably greater than 99.2%, particularly preferably greater than 99.5% and very particularly preferably greater than 99.9%, based on the total number of polysiloxane domains ≥ 12 nm, The present invention further provides a polysiloxane-polycarbonate block copolymer comprising:

[0095] At the same time, the polysiloxane-polycarbonate block copolymer has a relative solution viscosity of 1.24 to 1.34, preferably 1.26 to 1.33, particularly preferably 1.27 to 1.325.

[0096] The present invention has the following features: the polysiloxane content is 4% to 8% by weight based on the total weight of the polysiloxane-polycarbonate block copolymer; the numerical proportion of polysiloxane domains ≥ 12 nm and < 200 nm is in each case greater than 99.0%, preferably greater than 99.2%, particularly preferably greater than 99.5% and very particularly preferably greater than 99.9%, based on the total number of polysiloxane domains ≥ 12 nm, The present invention further provides a polysiloxane-polycarbonate block copolymer comprising:

[0097] At the same time, the polysiloxane-polycarbonate block copolymer has a relative solution viscosity of 1.24 to 1.34, preferably 1.26 to 1.33, particularly preferably 1.27 to 1.325.

[0098] The present invention has the following features: the polysiloxane content is 4.5% to 5.5% by weight based on the total weight of the polysiloxane-polycarbonate block copolymer; the numerical proportion of polysiloxane domains ≥ 12 nm and < 200 nm is in each case greater than 99.0%, preferably greater than 99.2%, particularly preferably greater than 99.5% and very particularly preferably greater than 99.9%, based on the total number of polysiloxane domains ≥ 12 nm, The present invention further provides a polysiloxane-polycarbonate block copolymer comprising:

[0099] At the same time, the polysiloxane-polycarbonate block copolymer has a relative solution viscosity of 1.24 to 1.34, preferably 1.26 to 1.33, particularly preferably 1.27 to 1.325.

[0100] The invention further provides the use of the polysiloxane-polycarbonate block copolymers according to the invention for the production of mouldings, such as, for example, housings, helmets, dishwasher-safe household items, kettle sight glasses, control knobs and buttons, snap closures, cake and chocolate moulds, plug connectors for photovoltaic power plants, couplings for photovoltaic power plants, etc.

[0101] As regards their use for the manufacture of housings, the polysiloxane-polycarbonate block copolymers according to the invention are suitable for the manufacture of housings for the following articles: Medical equipment, mobile electrical small appliances, mobile scanners, mobile play stations, mobile music players, wearable devices, sensors or computing equipment for the Internet of Things, mobile electrical charging equipment, mobile electrical adapters, control means for mechanical engineering, smart meters, mobile wireless devices, tablet computers, charging stations for electrical equipment, antenna housings for 5G base stations, outdoor electrical applications, switchboards, automated teller machines, parking meters.

[0102] The oligocarbonate used according to the invention and the hydroxyaryl-terminated polysiloxane used according to the invention are reacted with each other in step (4) using a cocatalyst.

[0103] Suitable catalysts for the process according to the invention for producing oligocarbonates, in particular oligocarbonates based on bisphenol A and diphenyl carbonate (DPC) as diphenol monomer units, include, for example: Ammonium catalysts such as tetramethylammonium hydroxide, tetramethylammonium acetate, tetramethylammonium fluoride, tetramethylammonium tetraphenylborate, dimethyldiphenylammonium hydroxide, tetraethylammonium hydroxide, cetyltrimethylammonium tetraphenylborate and cetyltrimethylammonium phenoxide. Particularly suitable catalysts include those of formula (K): [ka] (In the formula, R a , R b , R c and R d can be the same or different C1-C10 alkyl, C6-C14 aryl, C7-C15 arylalkyl or C5-C6 cycloalkyl, preferably methyl or C6-C14 aryl, particularly preferably methyl or phenyl; A - can be an anion such as hydroxide, sulfate, hydrogen sulfate, hydrogen carbonate, carbonate or a halide, preferably chloride, or an alkoxide or aroxide of formula -OR, where R can be C6-C14 aryl, C7-C15 arylalkyl or C5-C6 cycloalkyl, preferably phenyl).

[0104] Particularly preferred catalysts are tetraphenylphosphonium chloride, tetraphenylphosphonium hydroxide or tetraphenylphosphonium phenoxide, with tetraphenylphosphonium phenoxide being very particularly preferred. It is particularly preferred to use the alkali metal or alkaline earth metal salts of these ammonium and / or phosphonium catalysts.

[0105] The catalyst is preferably used in an amount of 0.0001% to 1.0% by weight, preferably 0.001% to 0.5% by weight, particularly preferably 0.005% to 0.3% by weight and very particularly preferably 0.01% to 0.15% by weight, based on the weight of the oligocarbonate used.

[0106] The catalysts can be used alone or as a catalyst mixture and can be added in pure form or as a solution, for example in water or phenol, for example as a solid solution with phenol. The catalysts can be introduced into the reaction, preferably together with the oligocarbonate, for example by means of a masterbatch, or can be added separately / additionally.

[0107] Oligocarbonates and hydroxyaryl-terminated polysiloxanes are mixed at pK values ​​ranging from 3 to 7. A It is also preferred to react in the presence of an organic or inorganic salt of a weak acid having a molecular weight of 0.1 to 0.25° C. (25° C.). This salt is also referred to as a cocatalyst in the context of the present invention. Suitable weak acids include carboxylic acids, preferably C2 to C22 carboxylic acids, such as acetic acid, propanoic acid, oleic acid, stearic acid, lauric acid, benzoic acid, 4-methoxybenzoic acid, 3-methylbenzoic acid, 4-tert-butylbenzoic acid, p-tolueneacetic acid, 4-hydroxybenzoic acid and salicylic acid, partial esters of polycarboxylic acids, such as monoesters of succinic acid, partial esters of phosphoric acid, such as mono- or di-organophosphates, branched aliphatic carboxylic acids, such as 2,2-dimethylpropionic acid, 2,2-dimethylbutanoic acid, 2,2-dimethylpentanoic acid and 2-ethylhexanoic acid.

[0108] Suitable organic or inorganic salts are selected or derived from hydrogen carbonate, potassium hydrogen carbonate, lithium hydrogen carbonate, sodium carbonate, potassium carbonate, lithium carbonate, sodium acetate, potassium acetate, lithium acetate, sodium stearate, potassium stearate, lithium stearate, sodium oleate, potassium oleate, lithium oleate, sodium benzoate, potassium benzoate, lithium benzoate, disodium, dipotassium or dilithium salts of bisphenol A. The salts may further comprise calcium hydrogen carbonate, barium hydrogen carbonate, magnesium hydrogen carbonate, strontium hydrogen carbonate, calcium carbonate, barium carbonate, magnesium carbonate, strontium carbonate, calcium acetate, barium acetate, magnesium acetate, strontium acetate, calcium stearate, barium stearate, magnesium stearate, strontium stearate and the corresponding oleates. All these salts can be used alone or in any desired mixture.

[0109] The salts are particularly preferably selected from the group consisting of the alkali metal, alkaline earth metal and phosphonium salts of carboxylic acids. In a further preferred embodiment, the organic or inorganic salts are derived from carboxylic acids.

[0110] According to the present invention, the organic or inorganic salt is 5×10 per kg of hydroxyaryl-terminated polysiloxane. -7 mol~1×10 -3 mol of cocatalyst, preferably 1×10 per kg of hydroxyaryl-terminated polysiloxane -6 mol~5×10 -4 mol of cocatalyst, particularly preferably 5×10 per kg of hydroxyaryl-terminated polysiloxane -6 mol~2×10 -4 mol of cocatalyst, very particularly preferably 1×10 per kg of hydroxyaryl-terminated polysiloxane -5 mol~1×10 -4 The amount of cocatalyst used is in moles.

[0111] In a preferred embodiment, the organic or inorganic salt is a sodium salt, preferably a sodium salt of a carboxylic acid. The cocatalyst is preferably dissolved in the hydroxyaryl-terminated polysiloxane in a suitable solvent. The sodium content of the polysiloxane-polycarbonate block copolymer can be determined, for example, by atomic absorption spectroscopy.

[0112] It is advantageous to have a lower sodium content in the resulting polysiloxane-polycarbonate block copolymer than the prior art, since higher sodium contents can increase decomposition of the polysiloxane-polycarbonate block copolymer under thermal stress.

[0113] The organic or inorganic salt, i.e., the cocatalyst, can be used alone or in any desired mixture. The cocatalyst may be added as a solid or in a solution. In a preferred embodiment, the organic or inorganic salt is added in the form of a mixture containing the hydroxyaryl-terminated polysiloxane and the organic or inorganic salt.

[0114] The catalysts may be used alone or in admixture with other catalysts and may be added in pure form or as a solution, for example in water or phenol. The cocatalysts may also be used alone or in admixture with other cocatalysts and may be added in pure form or as a solution.

[0115] It is particularly preferred when at least one catalyst is incorporated into the oligocarbonate and a co-catalyst is incorporated into the hydroxyaryl-terminated polysiloxane.

[0116] Oligocarbonate (Component A) The oligocarbonates in the context of the present invention (hereinafter also referred to as component (A)) are preferably homooligocarbonates. The oligocarbonates may be linear or branched in a known manner. The preparation of the oligocarbonates used according to the present invention is carried out as described above, preferably by a melt transesterification process, in particular according to WO 2019238419. The preparation of oligocarbonates useful in the process according to the present invention is also described in DE 10119851 A1, WO 02077066 A1, WO 02077067 A1 or WO 02085967 A1. The preparation of oligocarbonates useful in the process according to the present invention according to WO 02085967 A1 is particularly advantageous, in which the oligocarbonates are removed from a mesh basket reactor which forms the penultimate stage of the polycondensation to obtain the polycarbonate.

[0117] To prepare the polysiloxane-polycarbonate block copolymers according to the invention, it is preferable to use oligocarbonates having a molecular weight (Mw) of 5000 g / mol to 20000 g / mol, particularly preferably 8000 g / mol to 19000 g / mol, particularly preferably 10000 g / mol to 18000 g / mol. The oligocarbonates preferably have a phenolic OH group content of 1000 ppm to 2500 ppm, preferably 1300 ppm to 2300 ppm, particularly preferably 1400 ppm to 2200 ppm. The phenolic OH groups are preferably determined by IR spectroscopy. In the context of the present invention, ppm is understood to mean parts by weight, unless otherwise stated.

[0118] The method used to determine the molar masses reported in the context of this invention for oligocarbonates, hydroxyaryl-terminated polysiloxanes or polysiloxane-polycarbonate block copolymers is Method No. 2301-0257502-09D of Currenta GmbH & Co. OHG, available at any time upon request from Currenta GmbH & Co. OHG.

[0119] In the context of the present invention, the compound of formula: Mw(oligocarbonate)(g / mol)=160799×(solution viscosity-1)exp(1.3862) It is also possible to calculate the molar mass of the oligocarbonate by:

[0120] It is further preferred when oligocarbonates having a relative solution viscosity of 1.08 to 1.22 are used for the preparation of the polysiloxane-polycarbonate block copolymers according to the invention, where the relative solution viscosity (ηrel; also called eta rel) is preferably determined in dichloromethane at a concentration of 5 g / l at 25° C. using an Ubbelohde viscometer.

[0121] Preferred diphenols for the preparation of oligocarbonates are 4,4'-dihydroxydiphenyl, 2,2-bis(4-hydroxyphenyl)-1-phenylpropane, 1,1-bis(4-hydroxyphenyl)phenylethane, 2,2-bis(4-hydroxyphenyl)propane, 2,2-bis(3-methyl-4-hydroxyphenyl)propane, 2,4-bis(4-hydroxyphenyl)-2-methylbutane, 1,3-bis[2-(4-hydroxyphenyl)-2-propyl]benzene (bisphenol M), 2,2-bis(3-methyl-4-hydroxyphenyl)propane, 2,4-bis(4-hydroxyphenyl)-2-methylbutane, 1,3-bis[2-(4-hydroxyphenyl)-2-propyl]benzene (bisphenol M), 2,2-bis(3-methyl-4-hydroxyphenyl)propane, 2,4-bis(4-hydroxyphenyl)-2-methylbutane, 2,4-bis(4-hydroxyphenyl)-2-propyl]benzene ... bis(3,5-dimethyl-4-hydroxyphenyl)propane, bis(3,5-dimethyl-4-hydroxyphenyl)methane, 2,2-bis(3,5-dimethyl-4-hydroxyphenyl)propane, bis(3,5-dimethyl-4-hydroxyphenyl)sulfone, 2,4-bis(3,5-dimethyl-4-hydroxyphenyl)-2-methylbutane, 1,3-bis[2-(3,5-dimethyl-4-hydroxyphenyl)-2-propyl]benzene, 1,1-bis(4-hydroxyphenyl)cyclohexane, and 1,1-bis(4-hydroxyphenyl)-3,3,5-trimethylcyclohexane.

[0122] Particularly preferred diphenols are 2,2-bis(4-hydroxyphenyl)propane (BPA), hydroquinone, 1,1-bis(4-hydroxyphenyl)-3,3,5-trimethylcyclohexane and 2,2-bis(3-methyl-4-hydroxyphenyl)propane.

[0123] The oligocarbonates are in particular homooligocarbonates based on bisphenol A and diphenyl carbonate (DPC) as diphenol monomer building blocks. Very particular preference is given to the homooligocarbonates which contain phenol as end group.

[0124] Oligocarbonates having phenol as a terminal group (phenyl-terminated oligocarbonates) are also preferred. Tert-butylphenol and cumylphenol are further possible terminal groups.

[0125] The polysiloxane-polycarbonate block copolymers obtainable by the process according to the invention preferably comprise at least one, particularly preferably two or more, of the following structures (4) to (7): [ka] Here, the phenyl rings may be mono- or di-substituted, independently of one another, with C1-C8 alkyl, halogen, preferably C1-C4 alkyl, particularly preferably methyl, X represents a single bond, C1-C6 alkylene, C2-C5 alkylidene or C5-C6 cycloalkylidene, preferably a single bond or C1-C4 alkylene, particularly preferably isopropylidene, and the total amount of structural units (4)-(7) (preferably determined by total hydrolysis using quantitative HPLC) is generally in the range of 50 ppm-1000 ppm, preferably in the range of 80 ppm-850 ppm. For this reason, the polysiloxane-polycarbonate block copolymer produced according to the present invention preferably contains at least one of the above-mentioned structures (4)-(7), particularly preferably two or more.

[0126] To determine the amount of rearrangement structures, each polysiloxane-polycarbonate block copolymer is subjected to total hydrolysis to form the corresponding degradation products of formula (4a) to formula (7a), the amount of which is determined by HPLC. This can be achieved, for example, as follows: A polysiloxane-polycarbonate block copolymer sample is hydrolyzed under reflux with sodium methoxide. The corresponding solution is acidified and concentrated to dryness. The dry residue is dissolved in acetonitrile and the phenolic compounds of formula (4a) to formula (7a) are determined using HPLC with UV detection, where the compound of formula (4a) is a degradation product of the compound of formula (4), the compound of formula (5a) is a degradation product of the compound of formula (5), the compound of formula (6a) is a degradation product of the compound of formula (6), and the compound of formula (7a) is a degradation product of the compound of formula (7), and in all of these cases X is assumed to be isopropylidene: [ka]

[0127] The amount of the compound of formula (4a) thus liberated is preferably 10 ppm to 500 ppm, particularly preferably 30 ppm to 300 ppm.

[0128] The amount of the compound of formula (5a) thus liberated is preferably 0 ppm (ie, below the detection limit of 10 ppm) to 100 ppm, particularly preferably 1 ppm to 50 ppm.

[0129] The amount of the compound of formula (6a) thus liberated is preferably from 1 ppm (ie, below the detection limit of 10 ppm) to 100 ppm, more preferably from 1 ppm to 50 ppm.

[0130] The amount of the compound of formula (7a) thus liberated is preferably from 10 ppm (ie, detection limit of 10 ppm) to 300 ppm, preferably from 20 ppm to 250 ppm.

[0131] Hydroxyaryl-terminated polysiloxane (Component B) The polysiloxanes used according to the invention are hydroxyaryl-terminated, which means that at least one end of the polysiloxane, preferably at least two ends, and particularly preferably all ends (if three or more ends are present) have a hydroxyaryl end group.

[0132] Component B is represented by formula (1): [ka] (In the formula, R 5 is hydrogen or C 1 ~C 4 Alkyl, C 1 ~C 3 alkoxy, preferably hydrogen, methoxy or methyl; R 6 , R 7 , R 8 and R 9 are each independently C 1 ~C 4 Alkyl or C 6 ~C 12 aryl, preferably methyl or phenyl; Y is a single bond, SO 2 -, -S-, -CO-, -O-, C 1 ~C 6 Alkylene, C 2 ~C 5 Alkylidene, C 6 ~C 12 arylene, optionally fused to a further aromatic ring containing a heteroatom, or C 1 ~C 4 C optionally mono- or polysubstituted by alkyl 5 ~C 6 is a cycloalkylidene radical, preferably a single bond, -O-, isopropylidene, or C 1 ~C 4 C optionally mono- or polysubstituted by alkyl 5 ~C 6 is a cycloalkylidene radical, V is oxygen, C 2 ~C6 Alkylene or C 3 ~C 6 Alkylidene, preferably oxygen or C 3 is alkylene, p, q and r each independently represent 0 or 1; When q=0, W is a single bond, preferably simultaneously r=0, When q=1 and r=0, W is oxygen, C 2 ~C 6 Alkylene or C 3 ~C 6 Alkylidene, preferably oxygen or C 3 is alkylene, When q=1 and r=1, W and V are each independently oxygen or C. 2 ~C 6 Alkylene or C 3 ~C 6 Alkylidene, preferably C 3 is alkylene, Z is C 1 ~C 6 Alkylene, preferably C 2 is alkylene, o is the average number of repeat units from 10 to 500, preferably from 10 to 100; Preferably, the polysiloxane is a hydroxyaryl-terminated polysiloxane of the general formula (1a), in which m is the average number of repeating units from 1 to 10, preferably from 1 to 6, more preferably from 1.5 to 5. It is likewise possible to use diphenols in which two or more siloxane blocks of the general formula (1a) are linked to one another via terephthalic and / or isophthalic acid to form ester groups.

[0133] Equation (2) and Equation (3): [ka] (Wherein, R1 is hydrogen, C 1 ~C 4 alkyl, preferably hydrogen or methyl, particularly preferably hydrogen, each R2 is independently aryl or alkyl, preferably methyl; X is a single bond, -SO 2-, -CO-, -O-, -S-, C 1 ~C 6 Alkylene, C 2 ~C 5 Alkylidene or C 6 ~C 12 is arylene, optionally fused to a further aromatic ring containing a heteroatom; X is preferably a single bond, C 1 ~C 5 Alkylene, C 2 ~C 5 Alkylidene, C 5 ~C 12 Cycloalkylidene, -O-, -SO-, -CO-, -S-, -SO 2 -, and particularly preferably, X is a single bond, isopropylidene, C 5 ~C 12 cycloalkylidene or oxygen, very particularly preferably isopropylidene, n is an average number of 10 to 400, preferably 10 to 100, particularly preferably 15 to 50; (m is an average number of 1 to 10, preferably 1 to 6, and particularly preferably 1.5 to 5).

[0134] The siloxane block preferably has the following structure: [ka] In the formulae (VII), (VIII) and (IX), a represents an average number of 10 to 400, preferably 10 to 100, and particularly preferably 15 to 50.

[0135] It is also preferred here that at least two identical or different siloxane blocks of general formula (VII), general formula (VIII) or general formula (IX) are linked to one another via terephthalic acid and / or isophthalic acid to form an ester group.

[0136] In formula (1a), p=0 and V is C 3 alkylene, r=1, and Z is C2 alkylene, R 8 and R 9 is methyl, q=1, and W is C 3 alkylene, m=1, R 5 is hydrogen or C 1 ~C 4 alkyl, preferably hydrogen or methyl; R 6 and R 7 are each independently C 1 ~C 4 It is alkyl, preferably methyl, and the case where o is 10 to 500 is also preferred.

[0137] The preparation of hydroxyaryl-terminated polysiloxanes according to any of formulas (1) to (3) is described, for example, in EP 0122535, US 20130267665 or WO 2015 / 052229.

[0138] The hydroxyaryl-terminated polysiloxanes of formula (1), (2) or (3) or of formula (VII) or (VIII) are used in an amount of 0.5% to 50% by weight, preferably 1% to 40% by weight, particularly preferably 2% to 20% by weight and very particularly preferably 2.5% to 10% by weight, in each case based on the sum of the masses of the oligocarbonate and the hydroxyaryl-terminated polysiloxane.

[0139] The polysiloxane-polycarbonate block copolymers obtainable by the process according to the invention and the polymer compositions further prepared therefrom can be processed into any desired moldings in the manner known for thermoplastic polymers, in particular for polycarbonates.

[0140] In this connection, the polysiloxane-polycarbonate block copolymers obtainable by the process according to the invention and the polymer compositions further produced therefrom can be converted, for example, into articles, moldings or mouldings (summarised as moulded parts) by hot pressing, spinning, blow moulding, thermoforming, extrusion or injection moulding. The use in multi-layer systems is also interesting. The application of the compositions obtainable according to the invention can be, for example, in multi-component injection moulding or as a substrate for coextrusion layers. However, application can also be to pre-formed bodies, for example by lamination with a film or coating with a solution.

[0141] Sheets or mouldings (multilayer systems) consisting of a base layer and optional outer layer(s) can be produced by (co)extrusion, direct skinning, direct coating, insert moulding, in-mold coating or any other suitable method known to the skilled person.

[0142] The polysiloxane-polycarbonate block copolymers obtainable by the process according to the invention and the polymer compositions, in particular the polycarbonate compositions, further produced therefrom can be used in any field where known aromatic polycarbonates have been used up to now and where good flowability, high toughness at low temperatures and better chemical resistance, in addition to improved demolding properties, are additionally required, for example in the production of exterior parts and exterior control boxes, seats, twin-wall seats, electrical and electronic components for large automobiles, as well as optical storage media.The polysiloxane-polycarbonate block copolymers obtainable by the process according to the invention can thus be used in the IT field for computer housings and multimedia housings, mobile phone housings, in the household field for washing machines or dishwashers, etc., and in the sports field, for example as material for helmets. EXAMPLES

[0143] The present invention will now be described in more detail with reference to examples, but is not intended to be limited to these examples in any way. Hereinafter, the following determination methods will be used for all corresponding parameters in the present invention, unless otherwise stated.

[0144] Relative Solution Viscosity The relative solution viscosity (η rel; also called eta rel) was determined in dichloromethane at a concentration of 5 g / l at 25° C. using an Ubbelohde viscometer.

[0145] Characterization of polysiloxane domain size by atomic force microscopy (AFM) The polysiloxane domain size was determined by atomic force microscopy. For this purpose, each sample (in the extrusion batches in the form of pellet material) was sectioned under nitrogen cooling (-196°C) using an ultramicrotome. A Bruker D3100 AFM microscope was used. The AFM images were recorded at room temperature (25°C, 30% relative humidity). The "soft intermittent contact mode" or "tapping mode" was used for the measurements. Approximately 2.8 Nm -1 A "tapping mode cantilever" (pointprobe from Nanoworld) with a spring constant of 0.01 and a resonant frequency of about 75 kHz was used to scan the sample. The tapping force is controlled by the ratio of the target amplitude to the free vibration amplitude (amplitude of the probe tip oscillating freely in air). The sampling rate was set to 1 Hz. To document the surface morphology, phase contrast and topography images were recorded with an area of ​​2.5 μm × 2.5 μm. Polysiloxane domains were automatically evaluated by light-dark contrast from the phase contrast images using Olympus SIS image processing software (Olympus Soft Imaging Solutions GmbH, 48149, Münster, Germany). The diameter of the polysiloxane domains was determined by the diameter of the circle-equivalent projected area of ​​the cross-section of the polysiloxane domains seen by cutting. The resolution of the image evaluation was 12 nm.

[0146] Starting material: Oligocarbonate (Component A) The starting material used to prepare the polysiloxane-polycarbonate block copolymer was a linear bisphenol A oligocarbonate with phenyl end groups and phenolic OH end groups and a relative solution viscosity of 1.17. This oligocarbonate did not contain any additives such as UV stabilizers, mold release agents or heat stabilizers. The oligocarbonate was prepared by the melt transesterification method described in WO 02085967 and was immediately removed at the outlet from the first horizontal reactor. The oligocarbonate had a phenolic end group content of 0.16%.

[0147] The oligocarbonates were dried at 120° C. in a circulating air oven for at least 2 hours before use.

[0148] Hydroxyaryl-terminated polysiloxane containing a compatibilizer (Component B1) The hydroxyaryl-terminated polysiloxanes used had a hydroxy content of 14 mg KOH / g to 20 mg KOH / g and a viscosity (23°C) of 350 mPas to 650 mPas, with n ranging from 25 to 32 and m ranging from 2.5 to 4 (R 1 =H, R 2 = methyl; X = isopropylidene), the bisphenol A terminated polydimethylsiloxane of formula (3). Sodium benzoate was mixed into the polysiloxane, and the sodium content was 0.3 ppm to 1.5 ppm. One part of the siloxane Dow Corning™ 40-001 (Dow Corning Corporation) was added as a compatibilizer to 9 parts of the hydroxyaryl terminated polysiloxane.

[0149] Hydroxyaryl-terminated polysiloxane without compatibilizer (component B2) The hydroxyaryl-terminated polysiloxanes used had a hydroxy content of 14 mg KOH / g to 20 mg KOH / g and a viscosity (23°C) of 350 mPas to 650 mPas, with n ranging from 25 to 32 and m ranging from 2.5 to 4 (R 1 =H, R 2= methyl; X = isopropylidene), the bisphenol A-terminated polydimethylsiloxane of formula (3) was mixed with sodium benzoate, and the sodium content was 0.8 ppm to 1.3 ppm.

[0150] Experimental setup for Example 7 and Example 8 (invention) using exactly one special condensation reactor FIG. 4 shows the experimental setup for the experiments relating to one of the embodiments of the method according to the invention, steps (1) to (5) of the method according to the invention in an embodiment in which exactly one special condensation reactor, in this setup exactly one thin-film evaporator, is used for the production of polysiloxane-polycarbonate block copolymers by polycondensation.

[0151] The oligocarbonate (component A) and the hydroxyaryl-terminated polysiloxane containing a compatibilizer (component B1) were introduced as a physical mixture in the form of pelletized material by means of a weighing balance 4 into the plasticizing extruder 1 where they were melted.

[0152] The thin film evaporator 2 was evacuated using a vacuum pump 8. The off-gas was passed to a condenser 9 where the condensable components, especially phenols, were separated. The resulting polysiloxane-polycarbonate block copolymer was discharged from the thin film evaporator 2 via a gear pump 3, spun through a die plate (not shown) and pelletized.

[0153] The thin-film evaporator 2 is 0.5 m 2 The reaction chamber surface area of ​​the thin film evaporator 2 was wiped by a vertical rotor having four wiper blade elements around its periphery.

[0154] Experimental setup for Example 9 and Example 10 (invention) using exactly two special condensation reactors FIG. 1 shows the experimental setup for the experiments on one of the embodiments of the method according to the invention, steps (1) to (5) of the method according to the invention in the embodiment in which exactly two special condensation reactors, in this setup exactly two thin-film evaporators, are used for the production of polysiloxane-polycarbonate block copolymers by polycondensation. The oligocarbonate (component A) was introduced in the form of pellet material by means of a weighing balance 4 into the plasticizing extruder 1 and melted. The hydroxyaryl-terminated polysiloxane (component B) was fed in liquid form into a reservoir vessel 6 and was metered continuously into the plasticizing extruder 1 via a pump 7. The metering of the hydroxyaryl-terminated polysiloxane into the plasticizing extruder 1 was carried out in the melt of the oligocarbonate, i.e. downstream of the plasticizing zone of the extruder 1. The plasticizing extruder carried out a premixing of components A and B. The mixture was fed into an INDAG DLS / M 007 dynamic mixer 5. The mixer was operated at 500 rpm. The resulting molten mixture was subsequently sent to the first thin film evaporator 2. The first thin film evaporator 2 was evacuated using a vacuum pump 9. The off-gas was passed to a condenser 8, where the condensable components, in particular phenol, were separated. After being discharged from the first thin film evaporator 2, the resulting reaction mixture, containing the intermediate polysiloxane-polycarbonate block copolymer and the unconverted oligocarbonates and the unconverted hydroxyaryl-terminated polysiloxanes, was sent by a gear pump 3 through a melt conduit to a second thin film evaporator 2'. After the second thin film evaporator 2', the resulting polysiloxane-polycarbonate block copolymer was spun through a die plate (not shown) using a gear pump 3' and pelletized. The second thin film evaporator 2' was also evacuated via a vacuum pump 9', and the condensable components of the off-gas, in particular phenol, were separated in a condenser 8'.

[0155] The two thin-film evaporators 2 and 2' each have a thickness of 0.5 m 2 The reaction chamber surface areas of the two thin film evaporators 2 and 2' were each wiped by a vertical rotor having a number of wiper blade elements on its periphery, in particular exactly four wiper blade elements.

[0156] Experimental setup using a twin screw extruder (For the preparation of intermediate polysiloxane-polycarbonate block copolymers used in Comparative Examples 3 and 4, and Comparative Examples 1 and 2) The scheme of the experimental setup is evident from FIG.

[0157] FIG. 2 shows a scheme for the preparation of polysiloxane-polycarbonate block copolymers. The oligocarbonate (component A) was metered into the twin-screw extruder 1 via a gravimetric feeder 2. The extruder (ZSE 27 MAXX, Leistritz Extrusionstechnik GmbH, Nuremberg) was a co-rotating twin-screw extruder 1 with a vacuum zone for the removal of vapors. The twin-screw extruder 1 consisted of eleven barrel sections (a-k), see FIG. 2. The addition of the oligocarbonate (component A) was carried out in barrel section a via a differential weighing balance 2, and the melting of the oligocarbonate was carried out in barrels b and c. Barrel sections d and e were also used to incorporate the liquid hydroxyaryl-terminated polysiloxane (component B). Barrel sections e, g, i and j were equipped with vents for the removal of condensation products, especially phenol. Barrel section e was assigned to the first vacuum stage, barrel sections g, i and j to the second vacuum stage. The pressure in the first vacuum stage was 45 mbara to 65 mbara, unless otherwise stated. The pressure in the second vacuum stage was less than 1 mbara. The hydroxyaryl-terminated polysiloxane (component B) was initially charged in tank 3 and introduced into twin-screw extruder 1 via metering pump 4. Negative pressure was generated via vacuum pumps 5 and 6. Steam was withdrawn from twin-screw extruder 1 and passed through two condensers 7 and 8, where the condensation products, in particular phenol, were condensed. The molten strands of polysiloxane-polycarbonate block copolymer were passed through a water bath 9 and comminuted by a granulator 10.

[0158] Experimental setup using high viscosity reactor (For Comparative Examples 5 and 6, and as a preliminary step for Examples 7 to 10) The scheme of the experimental setup is evident from FIG.

[0159] Figure 3 shows a scheme for the preparation of polysiloxane-polycarbonate block copolymers. The oligocarbonate (component A) was metered into the twin-screw extruder 1 via a gravimetric feed means 4. The twin-screw extruder 1 (ZSE 27 MAXX, Leistritz Extrusionstechnik GmbH, Nuremberg) was a co-rotating twin-screw extruder with a vacuum zone for the removal of vapors. The twin-screw extruder 1 consisted of eleven barrel sections (a-k), see Figure 3. The addition of the oligocarbonate took place in barrel section a, and the melting of this oligocarbonate took place in barrel sections b and c. The addition of the liquid hydroxyaryl-terminated polysiloxane (component B) took place in barrel section d. Barrel sections e and f were used to incorporate the liquid hydroxyaryl-terminated polysiloxane. Barrel sections g, h, i and j were equipped with vents for the removal of condensation products. Barrel sections g and h were assigned to the first vacuum stage, and barrel sections i and j were assigned to the second vacuum stage. The pressure in the first vacuum stage was 250 mbara to 500 mbara, unless otherwise stated. The pressure in the second vacuum stage was less than 1 mbara. The hydroxyaryl-terminated polysiloxane was initially charged in a tank 6 and introduced into the twin-screw extruder 1 via a metering pump 7. Negative pressure was generated via two vacuum pumps 8. Vapors were drawn off from the twin-screw extruder 1 and collected in two condensers 9. The melt thus degassed and partially condensed was sent from barrel section k of the twin-screw extruder 1 via a conduit to the high-viscosity reactor 2.

[0160] The high-viscosity reactor 2 was a self-cleaning device with two counter-rotating rotors arranged horizontally and axially parallel. This setup is described in EP 0 460 466 A, see FIG. 7 therein. The high-viscosity reactor 2 used had a barrel diameter of 187 mm with a length of 924 mm. The inside of the high-viscosity reactor 2 had a total volume of 44.6 liters. The high-viscosity reactor 2 was likewise connected to a vacuum pump 8 and a condenser 9. The pressure in the high-viscosity reactor 2 was 0.1 mbara to 5 mbara. After the end of the reaction, the resulting polysiloxane-polycarbonate block copolymer was discharged via the discharge screw 3 and subsequently pelletized (via a water bath 10 and a granulator 11).

[0161] Comparative Example 1: Experiments with a rotating disk reactor The experimental setup according to Figure 2 was initially used for the preparation of intermediate polysiloxane-polycarbonate block copolymers. For this purpose, 9.5 kg / h of oligocarbonate (component A) with a relative solution viscosity of 1.17 were metered into barrel a of a twin-screw extruder 1 (see Figure 2). The compatibilizer and 5.22 x 10 per kg of hydroxyaryl-terminated polysiloxane used were added. -5 A hydroxyaryl-terminated polysiloxane (component B1) containing 1.2 ppm Na, based on the mass of the hydroxyaryl-terminated polysiloxane used, corresponding to 1.0 mol Na, was introduced at 0.475 kg / h into barrel d of the twin-screw extruder 1. The twin-screw extruder 1 was operated at a speed of 400 rpm.

[0162] The extruder barrels were heated according to the following scheme: barrel a was unheated, barrel b was at 170°C, barrels c and d were at 240°C, barrel e was at 250°C, barrel f was at 260°C, barrel g and h were at 270°C, barrel i was at 275°C, barrel j was at 285°C, and barrel k was at 295°C. A pressure of 40 mbara was applied to barrel e. A pressure of 0.6 mbara was applied to barrels g, i, and j. The intermediate polysiloxane-polycarbonate block copolymer was extruded at a melt temperature of 323°C, passed through a water bath 10, and pelletized.

[0163] 10 kg of the intermediate polysiloxane-polycarbonate block copolymer thus produced was melted in a rotating disk reactor of Uhde Inventa Fischer GmbH, with two disks, each with a diameter of 800 mm. The melt was polycondensed in the rotating disk reactor at 300° C. and 1 mbara for 87 minutes, with a rotor speed of 2.5 rpm. Phenol was continuously removed. The polysiloxane-polycarbonate block copolymer thus obtained was discharged and pelletized. The polysiloxane-polycarbonate block copolymer thus obtained had a relative solution viscosity of eta rel 1.26.

[0164] The reactor disk has a surface area of ​​2 m2 for application of the reaction mixture. 2 The application rate based on the surface area over which the reaction mixture is applied is 3.4 kg / m 2 h.

[0165] Comparative Example 2: Experiments with a rotating disk reactor 10 kg of intermediate polysiloxane-polycarbonate block copolymer (FIG. 2), produced using twin-screw extruder 1 as in Comparative Example 1, was melted in the rotating disk reactor of Comparative Example 1. The intermediate polysiloxane-polycarbonate block copolymer was polycondensed in the rotating disk reactor at 300° C. and 1 mbar for 110 minutes at a speed of 2.5 rpm. Phenol was continuously removed. The polysiloxane-polycarbonate block copolymer obtained was discharged and pelletized. The polysiloxane-polycarbonate block copolymer thus obtained has a relative solution viscosity of eta rel 1.33.

[0166] The size of the polysiloxane domains in the polysiloxane-polycarbonate block copolymers of Comparative Example 1 and Comparative Example 2 was determined by AFM as further described above. In the polysiloxane-polycarbonate block copolymer of Comparative Example 1, the numerical ratio of polysiloxane domains 12 nm or more and less than 200 nm was found to be 96.8% based on the total number of polysiloxane domains 12 nm or more. In the polysiloxane-polycarbonate block copolymer of Comparative Example 2, the numerical ratio of polysiloxane domains 12 nm or more and less than 200 nm is 98.9% based on the total number of polysiloxane domains 12 nm or more. Experience has shown that polysiloxane domains with a size of 200 nm or more in particular cause significant surface defects in injection molded articles. Polysiloxane domains with a size of 200 nm or more may also cause deterioration of the aesthetic appearance of injection molded articles. Therefore, the products of Comparative Example 1 and Comparative Example 2 do not meet the requirement of a high percentage of small polysiloxane domains.

[0167] The reactor disk has a surface area of ​​2 m2 for application of the reaction mixture. 2 The application rate based on the surface area over which the reaction mixture is applied is 2.7 kg / m 2 h.

[0168] Comparative Example 3: Experiments using a twin screw extruder Using the experimental setup according to Figure 2, 1.2 kg / h of oligocarbonate (component A) were metered into the twin-screw extruder 1 via the gravimetric addition means 2. The extruder speed was set at 190 rpm. The concentration of 5.22 x 10 per kg of hydroxyaryl-terminated polysiloxane used was -50.060 kg / h of hydroxyaryl-terminated polysiloxane containing a compatibilizer (component B1), containing 1.2 ppm Na based on the mass of the hydroxyaryl-terminated polysiloxane used, corresponding to 1.0 mol Na, was introduced into barrel d of twin-screw extruder 1 via pump 4. A negative pressure of 40-50 mbara was applied to barrel e, and a negative pressure of 0.5 mbara was applied to each of barrels g, i and j. The extruder barrels were heated according to the following scheme: barrel a was unheated, barrel b was at 170°C, barrels c and d were at 240°C, barrel e was at 250°C, barrel f was at 260°C, barrels g and h were at 270°C, barrel i was at 275°C, barrel j was at 285°C, and barrel k was at 295°C.

[0169] In the section of the extruder equipped with barrels g to k usable for polycondensation, 0.229 m 2 is available for application of the reaction mixture. This surface area is comprised of the surface area of ​​the two screw shafts and the barrel bore. The application rate of the extruder based on the surface area to which the reaction mixture is applied is 5.5 kg / m 2 It was h.

[0170] The resulting polysiloxane-polycarbonate block copolymer was light in color and had a length of 5.8 cm. 3 / 10min / eta rel has an MVR of 1.318.

[0171] Comparative Example 4 Experiments using a twin screw extruder Using the experimental setup according to Figure 2, 2.0 kg / h of oligocarbonate (component A) were metered into the twin-screw extruder 1 via the gravimetric addition means 2. The speed of the twin-screw extruder 1 was set at 380 rpm. -50.10 kg / h of hydroxyaryl-terminated polysiloxane (component B1) containing 1.2 ppm Na based on the mass of the hydroxyaryl-terminated polysiloxane used, corresponding to 1.0 mol Na, was introduced into barrel d of twin-screw extruder 1 via pump 4. A negative pressure of 40-50 mbara was applied to barrel e, and a negative pressure of 0.5 mbara was applied to each of barrels g, i and j. The extruder barrels were heated according to the following scheme: barrel a was unheated, barrel b was at 170°C, barrels c and d were at 240°C, barrel e was at 250°C, barrel f was at 260°C, barrels g and h were at 270°C, barrel i was at 275°C, barrel j was at 285°C, barrel k was at 295°C.

[0172] The resulting polysiloxane-polycarbonate block copolymer was light in color and had an eta rel of 1.270.

[0173] The surface area for applying the reaction mixture in the region of the extruder utilized for polycondensation is 0.229 m 2 The application rate based on the surface area of ​​the extruder over which the reaction mixture is applied is 9.2 kg / m 2 It was h.

[0174] In Comparative Examples 3 and 4, a twin screw extruder was used in process step 2. Comparative Example 3 could demonstrate that a high percentage of small polysiloxane domains is achievable. Comparative Example 3 shows that the polysiloxane-polycarbonate block copolymer does not contain domains larger than 200 nm. However, the application rate based on the surface area of ​​the reaction mixture application is very low in Comparative Example 3. Since the polycondensation process without phenol generally scales with the surface area available for mass transfer to the gas phase, this process cannot be transferred to an industrial scale for continuous production of 100 kg / h to more than 500 kg / h of polysiloxane-polycarbonate block copolymer in one production line.

[0175] To allow a higher throughput in Comparative Example 4, the screw speed was increased by more than 2 times and the application rate based on the surface area where the reaction mixture is applied was increased by about 80%. It is clear from Table 1 that the domains become larger. Even domains larger than 500 nm occur. The viscosity also decreases. Thus, a further increase in the throughput would be expected to worsen the product quality in terms of viscosity and polysiloxane domain size. The application rate based on the surface area where the reaction mixture is applied is higher than in Comparative Example 3, but is still not satisfactory. Furthermore, the quality requirements are not met. In view of Patent Document 3, it is particularly surprising here that when an extruder is used for the last method step, scale-up to an industrial process is not possible / the product quality is too poor at the throughput required for an industrial process.

[0176] Therefore, Comparative Example 3 and Comparative Example 4 show that the process using a twin-screw extruder is uneconomical. Therefore, it has been surprisingly shown that the process configuration for polysiloxane-polycarbonate block copolymers described in Patent Document 3 does not provide good product quality and is not economical.

[0177] Comparative Example 5 Experiments with a high viscosity reactor Using the experimental setup according to FIG. 3, 28.6 kg / h of oligocarbonate (component A) and compatibilizer were used, with 5.22×10 per kg of hydroxyaryl-terminated polysiloxane. -51.43 kg / h of hydroxyaryl-terminated polysiloxane (component B1) containing 1.2 ppm Na based on the mass of the hydroxyaryl-terminated polysiloxane used, corresponding to 1.0 mol Na, were metered into the twin-screw extruder 1. The speed of the twin-screw extruder 1 was 850 rpm. The extruder barrels were heated according to the following scheme: barrel a was unheated, barrel b was at 170° C., barrels c and d at 240° C., barrel e was at 250° C., barrel f was at 260° C., barrels g and h at 270° C., barrel i was at 275° C., barrel j was at 285° C., barrel k was at 295° C. A pressure of 140 mbara was applied to barrel e and a pressure of 0.8 mbara was applied to each of barrels g, i and j. The outlet temperature from the twin-screw extruder 1 was 308° C. The extruded polymer melt was transferred to the high-viscosity reactor 2 via a pipe conduit. The speed of the high-viscosity reactor 2 was 30 rpm. The barrel temperature of the high-viscosity reactor 2 was 330° C. The pressure inside the high-viscosity reactor 2 was 0.5 mbara. A light-colored polysiloxane-polycarbonate block copolymer having a relative solution viscosity of 1.376 was obtained. The internal surface area of ​​the reactor available for polycondensation, where the reaction mixture was applied, was 3 m 2 The application rate based on the internal surface area over which the reaction mixture is applied is 10 kg / m 2 h.

[0178] Comparative Example 6 Experiments with a high viscosity reactor Using the experimental setup according to FIG. 3, 23.8 kg / h of oligocarbonate (component A) and a compatibilizer were used, with 5.22×10 per kg of hydroxyaryl-terminated polysiloxane. -51.19 kg / h of hydroxyaryl-terminated polysiloxane (component B1) containing 1.2 ppm Na based on the mass of the hydroxyaryl-terminated polysiloxane used, corresponding to 1.0 mol Na, were metered into twin-screw extruder 1. The speed of the extruder was 700 rpm. The extruder barrels of twin-screw extruder 1 were heated according to the following scheme: barrel a was unheated, barrel b was at 170° C., barrel c and d were at 240° C., barrel e was at 250° C., barrel f was at 260° C., barrel g and h were at 270° C., barrel i was at 275° C., barrel j was at 285° C., and barrel k was at 295° C. Barrel e and each of barrels g, i and j were at standard pressure. The melt was transferred to high-viscosity reactor 2. The speed was 45 rpm. The barrel temperature of high-viscosity reactor 2 was at 310° C. The pressure applied to the barrel of high-viscosity reactor 2 was less than 1.6 mbara. A light colored polysiloxane-polycarbonate block copolymer was obtained having a relative solution viscosity of 1.31.

[0179] The application rate based on the surface area of ​​the high viscosity reactor to which the reaction mixture is applied is 8.25 kg / m 2 It was h.

[0180] Comparative Example 5 and Comparative Example 6 were carried out using a high viscosity reactor. Comparative Example 5 was able to achieve a high proportion of small polysiloxane domains, but at the expense of an excessively high viscosity. As is evident from Table 1, the viscosity could be reduced, but this resulted in a significant increase in the proportion of large polysiloxane domains. This indicates that this type of reactor is not suitable for producing polysiloxane-polycarbonate block copolymers with the desired characteristics. In addition, the application rate based on the surface area of ​​the reaction mixture application requires the use of a very large reactor when the process according to this example is converted to an industrial scale of continuously producing 100 kg / h to more than 500 kg / h of polysiloxane-polycarbonate block copolymers in one production line. Therefore, this process is uneconomical.

[0181] Example 7 (invention) using exactly one thin-film evaporator according to FIG. 4 In the experimental setup according to FIG. 2, initially 21 kg / h of oligocarbonate (component A) with a relative viscosity of 1.17 were metered into barrel a of the twin-screw extruder 1, and a compatibilizer and a hydroxyaryl-terminated polysiloxane concentration of 5.22×10 per kg were added. -5 Hydroxyaryl-terminated polysiloxane (component B1) containing 1.2 ppm Na based on the mass of the hydroxyaryl-terminated polysiloxane used, corresponding to 1.05 mol Na, was introduced into barrel d of twin-screw extruder 1 at 1.05 kg / h. Twin-screw extruder 1 was operated at a speed of 500 rpm. The extruder barrels of twin-screw extruder 1 were heated according to the following scheme: barrel a was unheated, barrel b was at 170° C., barrels c and d were at 240° C., barrel e was at 250° C., and barrels f to k were at 260° C. No negative pressure was applied. The absence of negative pressure means that very little, if any, of any reaction products formed, such as phenols, is discharged, so that essentially a physical mixture (blend) of oligocarbonate and polysiloxane without reactive bonds is formed.

[0182] The thus formed blend of oligocarbonate and polysiloxane is melted in a plasticizing extruder 1 and conveyed by means of a gear pump (not shown) to a thin film evaporator 2 according to FIG. 4. The blend is introduced into the thin film evaporator 2 at a melt temperature of about 265° C. and an application rate of 20 kg / h and condensed at a barrel temperature of 334° C. The pressure in the thin film evaporator 2 was 0.4 mbara. A light-colored pellet material with a relative solution viscosity of 1.30 was obtained.

[0183] The thin-film evaporator 2 has an inner surface area of ​​0.5 m2 for applying the reaction mixture. 2 The inner surface area of ​​the thin film evaporator 2, onto which the reaction mixture was applied, was wiped at a speed of 500 rpm by a vertical rotor having four wiper blade elements around its periphery.

[0184] The application rate based on the inner surface area of ​​the reaction chamber of the thin film evaporator to which the reaction mixture is applied is 40 kg / m 2 It was h.

[0185] Example 8 (invention) using exactly one thin-film evaporator according to FIG. 4 Exactly as described in Example 7, the oligocarbonate (Component A) and the compatibilizer were first mixed together in an amount of 5.22×10 per kg of the hydroxyaryl-terminated polysiloxane used. -5 A blend of hydroxyaryl-terminated polysiloxanes (component B1) was prepared, containing 1.2 ppm Na based on the mass of the hydroxyaryl-terminated polysiloxane used, corresponding to 1.2 ppm Na ... 2 The inner surface area of ​​the reaction chamber of the thin film evaporator 2, where the reaction mixture was applied, was wiped at a speed of 450 rpm by a vertical rotor having four wiper blade elements around its periphery.

[0186] A light colored pellet material was obtained having a relative solution viscosity of 1.285.

[0187] The application rate based on the inner surface area of ​​the reaction chamber of the thin film evaporator to which the reaction mixture is applied is 36 kg / m 2 It was h.

[0188] Two of the invention examples, inventive examples 7 and 8, show that a special condensation reactor with a high application rate based on the internal surface area to which the reaction mixture is applied makes it possible to produce block copolymers having solution viscosities within the range of the invention while observing the process parameters according to the invention, said copolymers having at the same time a high proportion of small polysiloxane domains.

[0189] The application rate, based on the internal surface area of ​​the reaction chamber to which the reaction mixture is applied, is significantly higher compared to the comparative example, indicating that it is possible to achieve a commercial scale process with a lower internal surface area of ​​the reaction chamber and therefore more economical.

[0190] Example 9 (invention) using exactly two thin film evaporators according to FIG. 36.9 kg / h of oligocarbonate (component A) was plasticized in the plasticizing extruder 1, which did not contain a compatibilizer but had a yield of 3.92 x 10 per kg of reaction mixture used. -5 2 kg / h of hydroxyaryl-terminated polysiloxane (component B2) containing 0.9 ppm Na based on the mass of the hydroxyaryl-terminated polysiloxane used, corresponding to 100 mol Na, were incorporated into the melt in a plasticizing extruder 1 to produce a premix. For further homogenization, the premix of oligocarbonate and hydroxyaryl-terminated polysiloxane was passed through a DLM / S 007 dynamic mixer 5 from INDAG Maschinenbau, operating at a speed of 500 rpm. At a temperature of 284° C., the premix was subsequently mixed in a reaction chamber having an inner surface area of ​​0.5 m 2 , to which the reaction mixture was applied. 2 The melt was discharged and pumped by means of a gear pump 3 into a reaction chamber having an inner surface area of ​​0.5 m2, into which the reaction mixture was applied. 2 The mixture was then transported to a second thin-film evaporator 2'.

[0191] The second thin film evaporator 2' was operated at a pressure of 1 mbara. The upper half of the reaction chamber of the thin film evaporator 2' was heated to 320°C, the lower half to 317°C. The melt was thus further condensed and discharged at 361°C via a gear pump 3'. The inner surface area of ​​the reaction chamber of the thin film evaporator 2, to which the reaction mixture is applied, was wiped at a speed of 330 rpm by a vertical rotor having four wiper blade elements on its periphery. The inner surface area of ​​the reaction chamber of the thin film evaporator 2', to which the reaction mixture is applied, was wiped at a speed of 220 rpm by a vertical rotor having four wiper blade elements on its periphery.

[0192] The application rate based on the total internal surface area of ​​the reaction chamber of both thin-film evaporators to which the reaction mixture is applied is 38.9 kg / m 2 It was h.

[0193] A bright polysiloxane-polycarbonate block copolymer was obtained with a relative solution viscosity of 1.324.

[0194] Example 10 (invention) using exactly two thin film evaporators according to FIG. 41 kg / h of oligocarbonate (component A) was plasticized in the plasticizing extruder 1, without compatibilizer, resulting in a total of 3.92 x 10 per kg of reaction mixture used. -5 2.32 kg / h of hydroxyaryl-terminated polysiloxane (component B2) with an OH number of 19.2 mg KOH / g, with the addition of 0.9 ppm Na based on the mass of the hydroxyaryl-terminated polysiloxane used, corresponding to 1000 mol Na, was incorporated into the melt in a plasticizing extruder 1 to produce a premix. For further homogenization, the premix of oligocarbonate and hydroxyaryl-terminated polysiloxane without compatibilizer was passed through a DLM / S 007 dynamic mixer 5 from INDAG Maschinenbau, operating at a speed of 500 rpm. At a temperature of 275° C., the premix was subsequently passed through a reaction chamber with an internal surface area of ​​0.5 m 2 , to which the reaction mixture was applied. 2 The melt was discharged using a gear pump 3 into a reaction chamber having an inner surface area of ​​0.5 m2, into which the reaction mixture was applied. 2 The mixture was then transported to a second thin-film evaporator 2'.

[0195] The second thin film evaporator 2' was operated at a pressure of 1 mbara. The second thin film evaporator 2' was uniformly heated to 310°C. The melt was thus further condensed and discharged at 325°C via a gear pump 3'. The inner surface area of ​​the reaction chamber of the thin film evaporator 2, to which the reaction mixture was applied, was wiped at a speed of 189 rpm by a vertical rotor having four wiper blade elements on its periphery. The inner surface area of ​​the reaction chamber of the thin film evaporator 2', to which the reaction mixture was applied, was wiped at a speed of 202 rpm by a vertical rotor having four wiper blade elements on its periphery.

[0196] A bright polysiloxane-polycarbonate block copolymer was obtained with a relative solution viscosity of 1.315.

[0197] The application rate based on the total internal surface area of ​​the reaction chamber of both thin-film evaporators to which the reaction mixture is applied is 43.3 kg / m 2 It was h.

[0198] Experiments 9 and 10 of the present invention demonstrate that the objectives are also achieved using two special condensation reactors arranged in series with a high application rate based on the internal surface area of ​​the reaction chamber to which the reaction mixture is applied. The advantageous combination of the desired solution viscosity and a high proportion of small polysiloxane domains is also achieved here. Furthermore, it was possible to reduce the dosage of the cocatalyst by 25% compared to the other examples. When using two special condensation reactors arranged in series, it was also possible to avoid the compatibilizer, without consequently losing the advantageous combination of the desired solution viscosity and a high proportion of small polysiloxane domains.

[0199] [Table 1]

Claims

1. A method for continuously producing a polysiloxane-polycarbonate block copolymer using exactly one special condensation reactor, comprising: The method comprises the following method steps: (1) A method step of providing an oligocarbonate having a relative solution viscosity of 1.08 to 1.22 and an OH group content of 1000 ppm to 2500 ppm; (2) A method step of mixing the oligocarbonate from step (1) with a hydroxyaryl-terminated polysiloxane to provide a reaction mixture containing the oligocarbonate and the hydroxyaryl-terminated polysiloxane; (3) A method step of introducing the reaction mixture provided in step (2) containing the oligocarbonate and the hydroxylaryl-terminated polysiloxane into the exactly one special condensation reactor; The special condensation reactor comprises a reaction chamber having a shaft with at least one spreader at the periphery, the spreader has an outer edge, and the outer edge of the at least one spreader rotates at a defined distance from the outer wall of the reaction chamber; (4) A method step of reacting the reaction mixture from step (3) to obtain a polysiloxane-polycarbonate block copolymer; The reaction mixture is conveyed from the inlet of the special condensation reactor to the outlet of the special condensation reactor; (5) A method step of discharging the polysiloxane-polycarbonate block copolymer obtained from step (4) from the special condensation reactor; Characterized in that In step (4), the following method conditions are observed in the exactly one special condensation reactor: (4.a) The pressure in the reaction chamber is 0.01 mbar a to 10 mbar a; (4.b) The temperature of the reaction mixture in the reaction chamber is 280 °C to 380 °C; (4.c) The peripheral speed of the at least one spreader at the periphery of the rotationally symmetric inner surface area of the reactor extending in the axial direction of the reactor is 1 m / s to 5 m / s; are observed, The application rate of the reaction mixture to the reaction chamber is 20 kg / m ２ h to 100 kg / m ２ h, and Before introducing the reaction mixture provided in step (2) containing the oligocarbonate and the hydroxyaryl-terminated polysiloxane into step (3), to this reaction mixture, based on the mass of the hydroxyaryl-terminated polysiloxane, 5×10 －７ mol to 1×10 －３ mol of a cocatalyst are incorporated, This cocatalyst is selected from one or more cocatalysts based on alkali metals and / or alkaline earth metals.

2. A method for continuously producing a polysiloxane-polycarbonate block copolymer using a plurality of special condensation reactors arranged in series, comprising: The method comprises the following method steps: (1) A method step of providing an oligocarbonate having a relative solution viscosity of 1.08 to 1.22 and an OH group content of 1000 ppm to 2500 ppm; (2) A method step of mixing the oligocarbonate from step (1) and the hydroxyaryl-terminated polysiloxane to provide a reaction mixture containing the oligocarbonate and the hydroxyaryl-terminated polysiloxane. (3) A method step of introducing the reaction mixture provided in step (2) containing the oligocarbonate and the hydroxylaryl-terminated polysiloxane into the first reactor of a number of special condensation reactors arranged in series. Each of the number of special condensation reactors arranged in series is provided with a reaction chamber having a shaft with at least one spreader at the periphery, the spreader has an outer edge, and the outer edge of the at least one spreader rotates at a specified distance from the outer wall of the reaction chamber; (4) A method step of reacting the reaction mixture from step (3) to obtain a polysiloxane-polycarbonate block copolymer. The reaction mixture is conveyed from the inlet of the first special condensation reactor to the outlet of the last special condensation reactor of the number of special condensation reactors arranged in series; (5) A method step of discharging the polysiloxane-polycarbonate block copolymer obtained from step (4) from the last special condensation reactor. characterized in that In step (4), the following method conditions in the last reactor of the number of special condensation reactors arranged in series: (4.a) The pressure in the reaction chamber of 0.01 mbar a to 10 mbar a. (4.b) The temperature of the reaction mixture in the reaction chamber of 280 °C to 380 °C. (4.c) The peripheral speed of the at least one spreader at the periphery of the rotationally symmetric inner surface area of the reactor extending in the axial direction of 1 m / s to 5 m / s. are observed. The application rate of the reaction mixture to the reaction chamber is 20 kg / m ２ h to 100 kg / m ２ h, and Before introducing the reaction mixture provided in step (2) containing the oligocarbonate and the hydroxyaryl-terminated polysiloxane into step (3), to this reaction mixture, based on the mass of the hydroxyaryl-terminated polysiloxane, 5 × 10 －７ mol to 1 × 10 －３ mol of a co-catalyst are incorporated. This cocatalyst is selected from one or more cocatalysts based on alkali metals and / or alkaline earth metals.

3. The method according to claim 1 or 2, wherein the cocatalyst is added in a specified amount to the hydroxyaryl-terminated polysiloxane already before step (2).

4. In method step (4), the following method conditions in the single special condensation reactor or the last special condensation reactor of the number of special condensation reactors arranged in series: (4.a) The pressure in the reaction chamber of the special reaction reactor is 0.1 mbar a to 6 mbar a. are observed.

5. The method according to claim 1 or 2, wherein the relative solution viscosity of the oligocarbonate provided in step (1) is 1.11 to 1.

22.

6. The method according to claim 1 or 2, wherein the polysiloxane content of both the polysiloxane-polycarbonate block copolymer produced according to the first embodiment of the method according to the present invention and the polysiloxane-polycarbonate block copolymer produced according to the second embodiment of the method according to the present invention is 2% by weight to 15% by weight, and the polysiloxane content is based on the total weight of the polysiloxane-polycarbonate block copolymer.

7. The method according to claim 6, wherein the polysiloxane content of the polysiloxane-polycarbonate block copolymer is 4.5% by weight to 5.5% by weight, and the polysiloxane content is based on the total weight of the polysiloxane-polycarbonate block copolymer.

8. The method according to claim 1 or 2, wherein in step (1), the reaction mixture containing an oligocarbonate having a relative solution viscosity of 1.08 to 1.22 and an OH group content of 1000 ppm to 2500 ppm and containing a hydroxyaryl-terminated polysiloxane is produced using a dynamic mixer and / or a static mixer.

9. In step (4) of the method, the following method conditions: In the first special condensation reactor, (4.1.a) the pressure in the reaction chamber is 1 mbar a to 10 mbar a, (4.1.b) the temperature of the reaction mixture in the reaction chamber is 270 °C to 350 °C, (4.1.c) the surface renewal frequency of the reaction mixture is 10 Hz to 30 Hz, In the last special condensation reactor, (4.2.a) the pressure in the reaction chamber is 0.1 mbar a to 3 mbar a, (4.2.b) the temperature of the reaction mixture in the reaction chamber is 280 °C to 370 °C, (4.2.c) the surface renewal frequency of the reaction mixture is 10 Hz to 30 Hz, are observed, The rate of application of the reaction mixture to the reaction chamber is 30 kg / m ２ h to 60 kg / m ２ The method of claim 2, wherein

10. The following features: The polysiloxane content is 2% by weight to 15% by weight based on the total weight of the polysiloxane-polycarbonate block copolymer, The numerical ratio of polysiloxane domains of 12 nm or more and less than 200 nm is more than 99.0% based on the total number of polysiloxane domains of 12 nm or more in each case, A relative solution viscosity of 1.24 to 1.34, A polysiloxane-polycarbonate block copolymer containing

11. Use of the polysiloxane-polycarbonate block copolymer according to claim 10 in the production of a molded article.

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