High-temperature (co)polycarbonates containing phthalimide and having improved rheological properties

1. A composition comprising

A) from 99.9 to 92 parts by weight (based on the sum of components A+B) of high molecular weight, thermoplastic, aromatic (co)polycarbonate having a molecular weight Mw (weight average) of at least 10 000 g·mol −1 and comprising structural units of one or more of formula(e) (Ia), (Ib) and (Ic),

where R in each case represents hydrogen, C 1 -C 4 alkyl, aryl or aralkyl;

B) from 0.1 to 8 parts by weight (based on the sum of components A+B) of one or more organically modified telechelic or comb polysiloxanes selected from the group consisting of polysiloxanes of general formulae (IIa) and (IIb)

where the radicals

R 1 are identical or different and represent alkyl radicals comprising from 1 to 4 carbon atoms,

A are identical or different and represent —R 2 —X, where

R 2 is a radical having the general formula (IIC)

R 3 is a divalent, optionally substituted alkyl or alkenyl radical comprising from 2 to 11 carbon atoms,

R 4 are identical or different at each occurrence and are divalent, optionally substituted alkyl or aralkyl radicals,

x independently of one another has a value of 0 or 1,

y independently of one another has a value of from 0 to 100 and

X is a vinyl, amino, carboxyl, epoxy or hydroxy group,

n, k and r each independently of one another represent a number between 0 and 200, subject to the proviso that n, k and r are not all 0,

and

C) optionally additives.

2. The composition as claimed in claim 1 , wherein the (co)polycarbonate A) has a molecular weight Mw (weight average) of from 15 000 g·mol −1 to 300 000 g·mol −1 .

3. The composition as claimed in claim 1 , wherein component A) is employed in amounts of from 99.7 to 94 parts by weight and component B) is employed in amounts of from 0.3 to 6 parts by weight (based on the sum of components A+B).

4. The composition as claimed in claim 1 , wherein said composition comprises an additive, a UV absorbers, a demolding auxiliary or a heat stabilizer, in an amount of from 50 to 5000 ppm by weight in each case, based on the sum of components A+B.

5. The composition as claimed in claim 1 comprising at least one of the following structures as structural units of formula (Ia) and/or (Ib)

6. A process for producing the composition as claimed in claim 1 comprising mixing the constituents to form a mixture and melt compounding and melt extruding the mixture at elevated temperature.

7. A method for producing a molded part utilizing the compositions as claimed in claim 1 .

8. A molded parts comprising the composition as claimed in claim 1 .

9. A method for producing blend comprising adding the composition as claimed in claim 1 .