DE4424399A1 - Polycarbonates with aliphatic, ketocarboxyl end groups, optionally in a mixture with known aromatic polycarbonates, their preparation and their use - Google Patents

Description

The present invention relates to a method for producing aromatic polycarbonates with aliphatic, ketocarboxyl end groups and with average molecular weights w (weight average, determined by light scattering) between 8,000 and 150,000, optionally in a mixture with known ones aromatic polycarbonates with w (weight average, determined by Light scattering) between 8000 and 150,000 from diphenols, 1 mol% to 20 mol%, based on moles of diphenols, chain terminators, phosgene and optionally branching according to the known polycarbonate production methods of the phase boundary process or the process in homogeneous Solution which is characterized in that chain terminators of the formula (I)

optionally in combination with a maximum of the same molar amounts of others, known chain breakers used.

In the chain terminators of the formula (I) -A- is a polymeric, aliphatic radical, which is produced by polymerization of unsaturated compounds, and B a functional group involved in polycarbonate production after the two-phase interface process or by the process in homogeneous phase (pyridinever drive) acts as a reactive part of the chain terminator (I). Preferred groups B are -OH or -Cl.  

The molecular weight n (number average molecular weight determined by Gel permeation chromatography) of the chain terminators of the formula (I) between 250 and 30,000, preferably between 1,000 and 10,000.

Preferred compounds of formula (I) with B = OH are obtained, for example ten by oxidation of isobutylene-isoprene copolymers according to DE-OS 21 47 874.

Isobutylene-isoprene copolymers are in turn by copolymerization of iso butylene and 0.3 mol% to 25 mol%, based on 1 mol of isobutylene monomer, Isoprene available and for example under the name butyl rubber commercially available. The diene is essentially in the 1,4 position linked before, small proportions 1,2-linkage, as in all commercial available butyl rubbers are present and are not completely suppressed, also lead to small proportions more sideways Carboxyl groups.

The oxidation of these isobutylene-isoprene copolymers according to DE-OS 21 47 874 takes place, for example, by means of ozone at a slightly elevated or at room temperature.

From the compounds of formula (I) with B = OH, the Acid chlorides with B = Cl can be obtained by using these compounds in chlorinated in the usual way with thionyl or sulfonyl chloride.

Examples of chain terminators of the formula (I) to be used according to the invention are following ozonization products of polyisobutylene isoprene rubbers with 0.3-25 mol% of copolymerized isoprene, which are characterized as follows:

PIB carboxylic acid I:
Acid number: 15 mg KOH / g, from this a molecular weight calculated: 3733 g / mol
Iodine number: <1
OH number <2

PIB carboxylic acid II:
Acid number: 190 mg KOH / g, from this a molecular weight calculated: 295 g / mol
Iodine number: <1
OH number <2

PIB carboxylic acid III:
Acid number: 32 mg KOH / g, from this a molecular weight calculated: 1750 g / mol
Iodine number: 2
OH number <2

PIB carboxylic acid IV:
Acid number: 6 mg KOH / g, from this a molecular weight calculated: 9333 g / mol
Iodine number: <1
OH number <2

Known other chains to be used in the method according to the invention terminators are, for example, phenols, carboxylic acid halides, sulfone acid chlorides or chlorocarbonic acid esters.

Examples of the known chain terminators to be used are phenol, p-tert-butylphenol, 2,6-dimethylphenol, p-isooctylphenol, acetyl chloride and Benzoyl chloride.

The present invention also relates to the invention Aromatic polycarbonates obtainable according to the process with end groups of Formula (Ia)

where A has the meaning given for formula (I), with w (weight average, determined by light scattering) between 8000 and 150,000, possibly in the  Mixture with known aromatic polycarbonates with w (weight average, determined by light scattering) between 8000 and 150,000, which from the Chain termination with the other known chain breakers result.

Medium molecular weight aromatic polycarbonates obtainable according to the invention Weights w (weight average determined by light scattering) between 8000 and 150,000 are preferably those of the formula (II)

wherein

-OZO- is a diphenolate residue with preferably 6 to 30 carbon atoms,
E and E 'are the same or different and at least one of the radicals E or E' is a radical of the formula (Ia)

corresponds to
wherein -A- has the meaning given for formula (I), and wherein the other end groups E and E 'result from the reaction with the other known chain terminators, optionally including phosgene, and wherein
p is the degree of polymerization which results from the molecular weights w of 8,000 to 150,000 and is between 5 and 600.

The polycarbonates or polycarbonate mixtures according to the invention have a very good chemical resistance.

From DE-OS 26 20 256 (Le A 16 686) polycarbonates are known, the alipha have carboxyl radicals as end groups. They are characterized by a ver better demoldability.

From DE-OS 26 36 783 (Le A 16 689) polycarbonates are known which carboxyl-containing segments with n greater than 600 included. The Segments containing COOH can also be monofunctional (page 5, third to last) Line of DE-OS).

Polycarbonates are also known from DE-OS 27 02 626 (Le A 17 356), the carboxyl-containing segments with n greater than 600, in particular between 1000 and 20,000 built in included. The segments can also be monofunctional be (page 6, paragraph 1 of the DE-OS).

Polycarbonate mixtures are known from DE-OS 27 16 304 (Le A 18 024), the polycarbonates can also contain aliphatic carboxyl radicals. The Polycarbonate mixtures in turn have improved mold release properties.

From DE-OS 36 18 378 (Le A 24 330) are poly (C₂-C₁₀-α-olefin) carbon acids with w from 2000 to 350 000 known that have a COOH functionality of Have 0.5 to 2.0 per molecule (page 5, lines 7 to 13 of DE-OS). These Carboxylic acids are used to make polyolefin-polycarbonate block copoly meren used (page 3, lines 7 to 10 of DE-OS). These Polyolefin-polycarbonate block copolymers are used industrially in for example as an adhesion promoter, compatibility improver or dispersant in incompatible, thermoplastic polymer blends. In contrast, they have polycarbonates or polycarbonate mixtures according to the invention the following Advantage: Due to the small inconsistency of the invention End groups will be a much more homogeneous polycarbonate respectively Obtained polycarbonate mixture.

Diphenols suitable for the production of the polycarbonates according to the invention Formula (III)

HO-Z-OH (III)

with preferably 6 to 30 carbon atoms are both mononuclear and more nuclear diphenols that can contain heteroatoms and under the conditions the production of polycarbonates and their thermal treatment of inert substi may have had.

For example, hydroquinone, resorcinol, dihydroxydiphenyl, bis (hydroxy phenyl) alkanes, bis (hydroxyphenyl) cycloalkanes, bis (hydroxyphenyl) sulfides, ethers, ketones, sulfoxides, sulfones and α, α-bis (hydroxyphenyl) diisopropyl called benzenes and their nuclear alkylated and nuclear halogenated compounds.

Suitable diphenols are described, for example, in US Pat. Nos. 3,028,365, 2 999 835, 3 062 781, 3 148 172 and 4 982 014, in the German disclosure writings 1 570 703 and 2 063 050 as well as in the monograph "H. Schnell, Chemistry and Physics of Polycarbonates, Interscience Publishers, New York, 1964 ".

Preferred diphenols are
4,4'-dihydroxybiphenyl,
2,2-bis (4-hydroxyphenyl) propane,
2,4-bis (4-hydroxyphenyl) -2-methylbutane,
1,1-bis (4-hydroxyphenyl) cyclohexane,
α, α-bis (4-hydroxyphenyl) -p-diisopropylbenzene,
2,2-bis (3-methyl-4-hydroxyphenyl) propane,
2,2-bis (3-chloro-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,
1,1-bis (3,5-dimethyl-4-hydroxyphenyl) cyclohexane,
α, α′-bis (3,5-dimethyl-4-hydroxyphenyl) -p-diisopropyl-benzene,
1,1-bis (4-hydroxyphenyl) -3,3,5-trimethylcyclohexane,
1,1-bis (4-hydroxyphenyl) -3-methylcyclohexane,
1,1-bis (4-hydroxyphenyl) -3,3-dimethylcyclohexane,
1,1-bis (4-hydroxyphenyl) -4-methyl-cyclohexane,
2,2-bis (3,5-dichloro-4-hydroxyphenyl) propane and
2,2-bis (3,5-dibromo-4-hydroxyphenyl) propane.

Particularly preferred diphenols are e.g. B .:
2,2-bis (4-hydroxyphenyl) propane,
2,2-bis (3,5-dimethyl-4-hydroxyphenyl) propane,
2,2-bis (3,5-dichloro-4-hydroxyphenyl) propane,
2,2-bis (3,5-dibromo-4-hydroxyphenyl) propane,
1,1-bis (4-hydroxyphenyl) cyclohexane,
1,1-bis (4-hydroxyphenyl) -3,3,5-trimethylcyclohexane,
1,1-bis (4-hydroxyphenyl) -3-methylcyclohexane,
1,1-bis (3,5-dimethyl-4-hydroxyphenyl) -4-methylcyclohexane.

In particular, 2,2-bis (4-hydroxyphenyl) propane and 1,1-bis (4-hydroxyphenyl) - 3,3,5-trimethylcyclohexane is preferred.

Any mixtures of the aforementioned diphenols can also be used become.

In order to improve the flow behavior, small amounts, preferably amounts between 0.05 and 2.0 mol% (based on moles) diphenols used), on tri- or more than trifunctional compounds, especially those with three or more than three phenolic hydroxyl groups in be used in a known manner. Some of the connections that can be used with three or more than three phenolic hydroxyl groups are, for example 1,3,5-tri- (4-hydroxyphenyl) benzene, 1,1,1-tri- (4-hydroxyphenyl) ethane, 2,6-bis- (2- hydroxy-5'-methyl-benzyl) -4-methylphenol, 2- (4-hydroxyphenyl) -2- (2,4-dihydroxy phenyl) propane, hexa- (4- (4-hydroxyphenylisopropyl) phenyl) orthoterephthal acid esters, tetra- (4-hydroxyphenyl) methane and 1,4-bis- (4 ′, 4 ′ ′ - dihydroxytriphenyl) - methyl) benzene. Some of the other three-functional compounds are 2,4-dihydroxybenzoic acid, trimesic acid, cyanuric chloride and 3,3-bis- (4-hydroxy- 3-methylphenyl) -2-oxo-2,3-dihydroindole.  

The production of the polycarbonates or polycarbonate mixtures according to the invention can essentially be carried out according to the following two known methods (cf. H. Schnell, "Chemistry and Physics of Polycarbonates", Polymer Review, Vol. IX, Page 27 ff., Interscience Publ. 1964):

1. According to the solution process in the disperse phase (so-called two-phase interface method)

The diphenols to be used are in an aqueous alkaline phase solved. For this purpose, the poly carbonate required chain terminators in amounts from 1.0 to 20.0 Mol%, based on moles of diphenol, in an organic solvent dissolved or in bulk, added. Then in the presence of an inert, preferably polycarbonate-dissolving organic phase with phosgene set. The reaction temperature is between 0 ° C and 40 ° C.

The addition of the necessary chain terminators in type and quantity as above indicated, can also take place during the phosgenation.

Suitable organic solvents for the chain terminators are examples as methylene chloride, chlorobenzene, mixtures of methylene chloride and Chlorobenzene, acetone, acetonitrile, toluene.

The reaction can be carried out by catalysts such as tributylamine or triethylamine be favored. To favor the installation of the chain breaker, can also use onium salts such as tetraalkylammonium halides Phase transfer catalysts can also be used.

If branching devices are used, their addition can be made before the order with phosgene or during phosgenation.

In addition to or instead of the diphenols, their chlorocarbonic acid can also be used esters are used.  

2. After the solution process in a homogeneous phase (also pyridine process called)

Here the diphenols are dissolved in organic bases such as pyridine, optionally with the addition of further organic solvents; then are, as described under 1., the manufacture of the Invention according to polycarbonates, chain terminators required in amounts of 1.0 up to 20.0 mol%, based on mol of diphenol, added at room temperature give.

Then it is reacted with phosgene. The reaction temperature is between 0 ° C and 40 ° C. Suitable organic bases other than pyridine are e.g. B. Triethylamine, tributylamine; suitable solvents are, for example Methylene chloride, chlorobenzene, toluene or mixtures of methylene chloride and chlorobenzene or toluene.

The polycarbonates according to the invention are isolated by the Ver driving variants 1 and 2 in a known manner. Suitable refurbishment the processes in particular are precipitation, spray drying and the like Evaporation of the solvent in vacuo.

When using branches, it is described as under 1 method.

In addition to the diphenols, up to 50 mol%, based on the Diphenols used, used by their bischlorocarbonic acid esters become.

The polycarbonates according to the invention can still before or after Processing the usual additives for thermoplastic polycarbonates such as Stabili catalysts, mold release agents, pigments, flame retardants, antistatic agents, fillers and reinforcing materials are added in the usual amounts.

The polycarbonates according to the invention can be processed into moldings for example by adding the polycarbonates isolated in a known manner  Extruded granules and these granules, if necessary after adding the above called additives by injection molding to various articles in a known manner processed.

The polycarbonates according to the invention can be used as moldings anywhere where the previously known polycarbonates were used, for example in Electrical sector and in the construction sector, namely when increased chemicals permanence is required.

Examples of uses are films, composite films, extrusion and Injection molded parts with and without fillers or glass fiber reinforcement such. B. Safety helmets, foams, sheets and blown bodies, as well as medical Articles such as tubing and short-term implants.

The polycarbonates obtainable by the process according to the invention can other thermoplastics can be mixed in the usual quantities.

Suitable other thermoplastics are, for example, aromatic polyester carbonates and polyalkylene terephthalates.

The properties of the polycarbonates according to the invention can thus additionally be modified.

In particular, non-reactive polyisobutylenes can also be used for other modes Fication of the polycarbonates according to the invention or the invention modern polycarbonate mixtures are added.

The present invention thus also relates to mixtures of

• A) 80-99 wt .-%, preferably 85-97 wt .-% of the invention Lichen polycarbonates or polycarbonate mixtures and
• B) 1-20 wt .-%, preferably 3-15 wt .-% of non-reactive polyiso butylenes.

Polyisobutylenes according to component B) of the present invention cationic polymers of olefins and optionally dienes with a Content of at least 85% isobutylene. Polyisobutylenes are under the buzzword "Polyisobutylene" on page 3539, volume 5, in Römpp Chemie Lexikon, 9th edition, 1992, Georg Thieme Verlag. The molecular weight of the invention Polyisobutylene used is 1000 to 5,000,000, preferably 10,000 up to 1 200 000 g / mol. This is determined by light scattering.

Dienes suitable as comonomers for isobutylene are, for example, butadiene, Isoprene, 2-chlorobutadiene (1,4), 2-bromobutadiene (1,3), pentadiene, hexadiene, 2- Ethylbutadiene- (1,3), 2-propylbutadiene- (1,3), pentadiene, hexadiene, 2-ethylbutadiene- (1,3), 2-propylbutadiene- (1,3), 2-phenylbutadiene- (1,3), 2-methylpentadiene- (1,3) or 3-propylene hexadiene. Other suitable olefinic comonomers are styrene, α- Methylstyrene, m / p-methylstyrene or divinylbenzene.

These mixtures are produced via the melt at temperatures from 220 ° C to 380 ° C.

With regard to the isolation of these mixtures according to the invention, the processing these mixtures according to the invention and their technical applicability Mixtures apply to those obtainable according to the invention above Designs made of polycarbonates or polycarbonate mixtures.

Examples General

Ozonization products of polyisobutylene-isoprene were used as ketocarboxylic acids rubbers which were characterized as follows:

PIB-carboxylic acid I:
Acid number: 15 mg KOH / g, from this a molecular weight calculated: 3733 g / mol
Iodine number: <1
OH number: <2

PIB-carboxylic acid II:
Acid number: 190 mg KOH / g, from this a molecular weight calculated: 295 g / mol
Iodine number: <1
OH number: <2

PIB-carboxylic acid III:
Acid number: 32 mg KOH / g, from this a molecular weight calculated: 1750 g / mol
Iodine number: 2
OH number: <2

PIB-carboxylic acid IV:
Acid number: 6 mg KOH / g, from this a molecular weight calculated: 9333 g / mol
Iodine number: <1
OH number: <2

example 1

Polycarbonate with 0.5 wt .-% polyisobutylene carboxylic acid (M = 3733) as part of the Chain terminator.

In a 1 l-4 neck breakwater flask, with stirrer, gas inlet tube, thermometer, reflux condenser and optionally a dropping funnel and pH electrode, 22.83 g (0.1 m) bisphenol A, 39.11 g are introduced at room temperature, with nitrogen (0.44 m) NaOH (45%) and 0.298 g phenol dissolved in 232 ml distilled water. 0.13 g of PIB-carboxylic acid I dissolved in 135 ml of dichloromethane and 135 ml of chlorobenzene are added. At temperatures between 20 ° C to 25 ° C, 16 g (0.16 m) of phosgene are introduced for 15 to 30 min with stirring (800 rpm). Then 0.11 ml of N-ethylpiperidine is added as a catalyst and the mixture is stirred at room temperature for 45 min. The reaction mixture is then acidified with dilute hydrochloric acid and the organic phase is separated off. The organic phase is then washed with ion-free water 5 to 10 × until residues of the acid and ionic components have been removed. The organic phase is then dried over anhydrous sodium sulfate and dried at 100 ° C. in a vacuum drying cabinet.
Yield: 25.2 g; η _rel = 1.324

Example 2

Polycarbonate with 1.0 wt .-% polyisobutylene carboxylic acid I (M = 3733) as part of the Chain terminator.

As example 1, but 0.295 g phenol and 0.26 g PIB-carboxylic acid I are used.
Yield: 25.1 g; η _rel = 1.312

Example 3

Polycarbonate with 2.0 wt .-% polyisobutylene carboxylic acid I (M = 3733) as part of the Chain terminator.

Like example 1, but 0.289 g phenol and 0.52 g PIB-carboxylic acid I are used.
Yield: 25.3 g; η _rel = 1.331

Example 4

Polycarbonate with 3.0 wt .-% polyisobutylene carboxylic acid I (M = 3733) as part of Chain terminator.

Like example 1, but 0.282 g phenol and 0.79 g PIB-carboxylic acid I are used.
Yield: 25.0 g; η _rel = 1.319

Example 5

Polycarbonate with 3.0 wt .-% polyisobutylene carboxylic acid I (M = 3733) as part of Chain terminator.

Like example 1, but 0.282 g phenol and 0.79 g PIB-carboxylic acid I are used and a pH of approx. 8-10 is maintained during phosgenation. Before adding the catalyst, the pH is then adjusted to 12 and this value is maintained during the post-condensation time. To adjust the pH, 2/3 of the stated sodium hydroxide solution was added via the dropping funnel if necessary.
Yield: 24.6; η _rel = 1.267

Example 6

Polycarbonate with 4.0 wt .-% polyisobutylene carboxylic acid I (M = 3733) as part of Chain terminator.

Like example 1, but 0.278 g phenol and 1.05 g PIB-carboxylic acid I are used.
Yield: 25.6 g; η _rel = 1.323

Example 7

Polycarbonate with 5.0 wt .-% polyisobutylene carboxylic acid I (M = 3733) as part of Chain terminator.

Like example 1, but 0.271 g phenol and 1.32 g PIB-carboxylic acid I are used.
Yield: 25.4 g; η _rel = 1.328

Example 8

Polycarbonate with 7.5 wt .-% polyisobutylene carboxylic acid I (M = 3733) as part of Chain terminator.

Like example 1, but 0.256 g phenol and 1.98 g PIB-carboxylic acid I are used.
Yield: 26.8 g; η _rel = 1.315

Example 9

Polycarbonate with 10.0 wt .-% polyisobutylene carboxylic acid I (M = 3733) as part the chain breaker.  

Like example 1, but 0.241 g phenol and 2.63 g PIB-carboxylic acid I are used.
Yield: 27.5 g; η _rel = 1.313

Example 10

Polycarbonate with 20.0 wt .-% polyisobutylene carboxylic acid I (M = 3733) as part the chain breaker.

Like example 1, but 0.181 g phenol and 5.27 g PIB-carboxylic acid I are used.
Yield: 29.6 g; η _rel = 1.323

Example 11

Polycarbonate with 3.0 wt .-% polyisobutylene carboxylic acid II (M = 295) as part of the Chain terminator.

Like example 1, but 0.047 g phenol and 0.79 g PIB-carboxylic acid II are used.
Yield: 24.32 g; η _rel = 1.325

Example 12

Polycarbonate with 3.0 wt .-% polyisobutylene carboxylic acid II (M = 295) as part of the Chain terminator.

As in Example 1, but 0.047 g of phenol and 0.79 g of PIB-carboxylic acid II are used and a pH of approx. 8-10 is maintained during phosgenation. Before adding the catalyst, the pH is then adjusted to 12 and this value is maintained during the post-condensation time. To adjust the pH, 2/3 of the stated sodium hydroxide solution was added via the dropping funnel if necessary.
Yield: 24.7; η _rel = 1.293

Example 13

Polycarbonate with 3.0 wt .-% polyisobutylene carboxylic acid II (M = 295) as part of the Chain terminator.

Like example 1, but 0.047 g of phenol and 0.79 g of PIB-carboxylic acid II are used and only added shortly before the addition of the catalyst.
Yield: 24.9 g; η _rel = 1.333

Example 14

Polycarbonate with 3.0 wt .-% polyisobutylene carboxylic acid III (M = 1750) as part the chain breaker.

Like example 1, but 0.263 g phenol and 0.79 g PIB-carboxylic acid III are used and added only shortly before the addition of the catalyst.
Yield: 24.5 g; η _rel = 1.339

Example 15

Polycarbonate with 3.0 wt .-% polyisobutylene carboxylic acid III (M = 1750) as part the chain breaker.

As in Example 14, but a pH of 8-10 is maintained during phosgenation. Before adding the catalyst, the pH is then adjusted to 12 and this value is maintained during the post-condensation time. To adjust the pH, 2/3 of the stated sodium hydroxide solution was added via the dropping funnel if necessary.
Yield: 24.7 g; η _rel = 1.294

Example 16

Polycarbonate with 3.0 wt .-% polyisobutylene carboxylic acid IV (M = 9333) as part the chain breaker.

Like example 1, but 0.292 g phenol and 0.79 g PIB-carboxylic acid IV are used.
Yield: 24.5 g; η _rel = 1.331

Example 17

Polycarbonate with 3.0 wt .-% polyisobutylene carboxylic acid IV (M = 9333) as part the chain breaker.

As in Example 16, but a pH of 8-10 is maintained during phosgenation. Before adding the catalyst, the pH is then adjusted to 12 and this value is maintained during the post-condensation time. To adjust the pH, 2/3 of the stated sodium hydroxide solution was added via the dropping funnel if necessary.
Yield: 24.4 g; η _rel = 1.303

Claims (4)

1. A process for the preparation of aromatic polycarbonates with aliphatic ketocarboxyl end groups and with average molecular weights w (weight average, determined by light scattering) between 8000 and 150,000, optionally in a mixture with known aromatic polycarbonates with w (weight average, determined by light scattering) between 8000 and 150,000, from diphenols, 1 mol% to 20 mol%, based on moles of diphenol, chain terminators, phosgene and optionally branching agents, according to the known polycarbonate production methods of the phase boundary process or the process in homogeneous solution, characterized in that chain terminators of the formula ( I) with a molecular weight n (number average molecular weight, determined by gel permeation chromatography) of 250 to 30,000, in which -A- is a polymeric, aliphatic radical, optionally in combination with maximum equal molar amounts of other known chain terminators. 2. Aromatic polycarbonates with end groups of the formula (Ia) in which -A- has the meaning given for formula (I) in claim 1,
with w (weight average, determined by light scattering) between 8000 and 150,000, optionally in a mixture with known aromatic polycarbonates with w (weight average, determined by light scattering) between 8000 and 150,000, which result from the chain termination with the other known chain terminators, obtainable according to The method of claim 1. 3. Polycarbonates with average molecular weights w (weight average determined by light scattering) between 8000 and 150,000 of the formula (II) wherein-OZO- is a diphenolate residue with preferably 6 to 30 C atoms,
E and E 'are the same or different and at least one of the radicals E or E' is a radical of the formula (Ia) corresponds to
wherein -A- has the meaning given for formula (I) in claim 1, and wherein the other end groups E and E 'break from the reaction with the other known chain, optionally with the inclusion of phosgene and wherein
p is the degree of polymerization which results from the molecular weights w of 800 to 150,000 and is between 5 and 600. 4. Mixtures of

• A) 80-99 wt .-%, preferably 85-97 wt .-% of the polycarbonates or polycarbonate mixtures obtainable according to claim 1 and
• B) 1-20 wt .-%, preferably 3-15 wt .-% of non-reactive poly isobutylenes.