Monofuctional polyacrylates, their production and their use for the production of polycarbonates

The invention relates to polyacrylates corresponding to formula (I) ##STR1## to their production in a quasi-ionic polymerization and to their use as monofunctional chain terminators, optionally in combination with typical other chain terminators, for the production of aromatic polycarbonates. The invention also relates to the polycarbonates or polycarbonate mixtures obtained using the compounds corresponding to formula (I) and to their use as additives for other thermoplastic polycarbonates.

This invention relates to a process for the production of monofunctional 
polyacrylates which have number average molecular weights M.sub.n in the 
range from 3,000 to 50,000 and preferably in the range from 5,000 to 
20,000 and a polydispersity D of &lt;1.5 and preferably &lt;1.2 and which 
correspond to formula (I) 
##STR2## 
in which X is a single bond, C.sub.1-8 alkylene, C.sub.2-12 alkylidene, 
cyclohexylidene, --S--, --CO-- or --O--, 
n is 0 or 1, 
R.sup.1 is H, CH.sub.3 or CN, 
R.sup.2 is C.sub.1-12 alkyl, C.sub.5-6 cycloalkyl, C.sub.7-15 aralkyl, 
C.sub.7-15 alkaryl, C.sub.6-18 aryl and C.sub.2-12 -alkoxyalkyl; the alkyl 
groups may also be completely or partly fluorinated, and 
m is an integer of from 30 to 500, preferably from 50 to 200 and more 
preferably from 75 to 175, 
characterized in that mercaptosilanes corresponding to formula (II) 
##STR3## 
in which X and n are as defined for formula (I) and 
R is C.sub.1-16 alkyl, C.sub.5-6 cycloalkyl, C.sub.7-15 aralkyl, C.sub.7-15 
alkaryl and C.sub.6-18 aryl, preferably CH.sub.3, 
are reacted with compounds corresponding to formula (III) 
##STR4## 
in which R.sub.1 and R.sub.2 are as defined for formula (I), 
in a quasi-ionic polymerization in the presence of catalysts at 
temperatures in the range from -50.degree. to 100.degree. C. with a molar 
ratio of (II) to (III) of from 1:5 to 1:1,000 and with a molar ratio of 
catalyst to compound (II) of from 1:500 to 1:0.1, the reaction being 
carried out in aprotic solvents, and on completion of polymerization the 
"living" polymers are deactivated with proton donors, such as for example 
CH.sub.3 OH or CH.sub.3 COOH, the phenolic siloxy group is hydrolyzed to 
the free phenol, for example with methanolic hydrochloric acid, and the 
phenol-terminated polyacrylates are isolated in known manner by 
evaporation of the solvents. 
The present invention also relates to the compounds corresponding to 
formula (I). 
The number average molecular weights M.sub.n are determined by gel 
chromatography after preliminary calibration. The weight average molecular 
weights M.sub.w were also determined by gel permeation chromatography. 
The polydispersity D is the ratio of the weight average molecular weight 
M.sub.w to the number average molecular weight M.sub.n, i.e. D=M.sub.w 
/M.sub.n. 
The compounds corresponding to formula (II) ar either commercially 
available, i.e. are known, or may be obtained by known methods by 
silylation of the corresponding mercaptans (cf. for example D. A. Evans, 
J. Am. Chem. Soc. 99, page 5009 (1977) and R. S. Glass, J. Organomet. 
Chem. 61 (83) 1973). 
Suitable mercaptosilanes corresponding to formula (II) are, preferably, 3- 
or 4-(trimethylsiloxy)-phenyl mercaptotrimethyl silane. 
The compounds corresponding to formula (III) are also known from the 
literature or may be obtained by methods known from the literature. 
Preferred compounds (III) are the (meth)acrylates in which R.sub.1 is H or 
CH.sub.3 and R.sub.2 is an optionally fluorinated C.sub.2-8 alkyl radical. 
Suitable catalysts are tris-(dimethylamino)-sulfonium fluorotrimethyl 
silicate (TASF), tetrabutyl ammonium fluoride (TBAF), 
tris-(dimethylamino)-sulfonium difluoride (TASHF.sub.2), tetraalkyl 
ammonium difluorides, potassium difluoride, aluminium alkyl halides and 
zinc halides. Zinc iodide is a particularly suitable catalyst. 
Processes for the ionic or quasi-ionic polymerization of polar monomers 
containing a double bond in the .alpha.-position to the polar group are 
known (cf. for example U.S. Pat. Nos. 4,351,924, 4,414,372 and 4,417,034). 
In these known processes, the ionic polymerization is initiated by 
initiators while the quasi-ionic polymerizations are initiated by 
initiators in the presence of nucleophilic or electrophilic catalysts. 
A process for the quasi-anionic production of poly(meth)acrylates having a 
narrow molecular weight distribution using mercaptosilanes as initiators 
is described in DE-OS 3 504 168 (Le A 23 590). 
On the basis of that publication, it was not logical to use the compounds 
corresponding to formula (II) because the phenolically formed 
oxygen-silicon bond is almost as stable as the sulfur silicon bond under 
reaction conditions. Accordingly, it was not foreseeable to the expert 
that compounds corresponding to formula (II), analogous to the 
mercaptosilanes described in DE-OS 3 504 168, would be suitable as 
initiators for the quasi-ionic polymerization and would lead to phenolic 
terminal silyl ether groups in the polyacrylates produced. 
Suitable aprotic solvents for the quasi-ionic polymerization are, for 
example, acetonitrile, toluene or tetrahydrofuran. 
The monofunctional polyacrylates according to the invention are eminently 
suitable for use as chain terminators in the production of aromatic 
polycarbonates, particularly by the interfacial process, optionally in 
conjunction with typical other chain terminators. 
Accordingly, the present invention also relates to the use of the 
polyacrylates corresponding to formula (I) as monofunctional chain 
terminators, optionally in combination with typical other chain 
terminators, for the production of aromatic polycarbonates or 
polycarbonate mixtures. 
Accordingly, the present invention also relates to a process for the 
production of aromatic polycarbonates or polycarbonate mixtures by the 
known interfacial polycondensation method from diphenols, phosgene and 
chain terminators in a mixture of aqueous-alkaline phase and organic phase 
in the presence of catalyst, characterized in that the chain terminators 
corresponding to formula (I) are used as the chain terminators in 
quantities of from 0.1 mol-% to 10 mol-%, based on mols diphenols, at most 
99 mol-% of the molar quantities of chain terminator (I) to be used being 
replaceable by typical other chain terminators. 
In other words, of the particular molar quantities of chain terminators to 
be used, which amount to between 0.1 mol-% and 10 mol-% and preferably to 
between 3 mol-% and 5 mol-%, based on mols diphenols, the chain 
terminators corresponding to formula (I) should make up from 100 mol-% to 
1 mol-%, preferably 100 mol-% to 50 mol-% and, more preferably, 100 mol-% 
to 75 mol-% while the typical other chain terminators make up from 0 mol-% 
to 99 mol-%, preferably 0 mol-% to 50 mol-% and, more preferably, 0 mol-% 
to 25 mol-%. 
In addition the present invention relates to the polycarbonates or 
polycarbonate mixtures obtainable by the process according to the 
invention. 
The molecular weights of the polycarbonates obtainable in accordance with 
the invention without the attached chain terminators, expressed as M.sub.n 
(number average molecular weight, as determined by gel chromatography 
after preliminary calibration), should be in the range from 2,000 g/mol to 
200,000 g/mol, preferably in the range from 5,000 g/mol to 150,000 g/mol 
and more preferably in the range from 7,500 g/mol to 100,000 g/mol. 
The weight average molecular weights of the polycarbonates obtainable in 
accordance with the invention without the attached chain terminators 
(M.sub.w, again determined by gel permeation chromatography) should be in 
the range from 4,000 to 400,000, preferably in the range from 10,000 to 
300,000 and more preferably in the range from 15,000 to 200,000. 
The molecular weights of the polycarbonates or polycarbonate mixtures 
obtainable in accordance with the invention, including the attached chain 
terminators, understandably depend on the choice of the chain terminator 
itself which, even in the case of the typical other chain terminators, 
have an M.sub.n of from 94 (for phenol) to about 300 to 400 (depending on 
the substituted phenols or carboxylic acid chlorides) and, in the case of 
the chain terminators of formula (I) according to the invention, have an 
M.sub.n in the range from 3,000 to 50,000. 
Accordingly, it is only possible to state a range for the average degree of 
polymerization of the polycarbonates or polycarbonate mixtures obtainable 
in accordance with the invention which depends upon the particular total 
molar quantity of chain terminator and not upon the particular type of 
chain terminator used. 
The degrees of polymerization "p" of the polycarbonates or polycarbonate 
mixtures obtainable in accordance with the invention are from 10 to 1,000 
and preferably from 30 to 80. 
The polycarbonates or polycarbonate mixtures obtainable in accordance with 
the invention are either elastomers which can be processed as 
thermoplastics or tough thermoplastics, depending on the molecular weight 
of the aromatic middle part and the attached chain terminator. 
Suitable catalysts for the synthesis of the polycarbonate (mixtures) 
according to the invention are, for example, tertiary amines, such as 
triethylamine or N-ethyl piperidine. The aqueous alkaline phase consists, 
for example, of aqueous sodium hydroxide or aqueous potassium hydroxide. 
The organic phase consists, for example, of CH.sub.2 Cl.sub.2 and/or 
chlorobenzene. 
The polycarbonates or polycarbonate mixtures obtainable in accordance with 
the invention are isolated by breaking the two-phase emulsion obtainable 
by the process, separating the phases and, after washing with acid (for 
example phosphoric acid), passing the dried organic phase through known 
evaporation extruders and granulating the resulting strand. In the case of 
the elastomers processible as thermoplastics, working up may also be 
carried out by precipitation in apolar solvents, for example hexane, 
heptane. 
Suitable diphenols for the production of the polycarbonates or 
polycarbonate mixtures according to the invention are, in particular, 
those corresponding to formula 
EQU HO--Z--OH (IV) 
in which Z is an aromatic C.sub.6-30 radical which may contain one or more 
aromatic nuclei, may be substituted and may contain aliphatic radicals, 
cycloaliphatic radicals, araliphatic radicals, --S--, --SO.sub.2 --, 
--CO-- or --O-- as bridge members. 
Examples of diphenols corresponding to formula (IV) are hydroquinone, 
resorcinol, dihydroxydiphenyls, bis-(hydroxyphenyl)-alkanes, 
bis-hydroxyphenyl)-cycloalkanes, bis-(hydroxyphenyl)-sulfides, 
bis-(hydroxyphenyl)-ethers, bis-(hydroxyphenyl)-ketones, 
bis-(hydroxyphenyl)-sulfones, bis-(hydroxyphenyl)-sulfoxides, .alpha., 
.alpha.'-bis-(hydroxyphenyl)-diisopropyl benzenes and ring-alkylated and 
ring-halogenated compounds thereof. 
These and other suitable diphenols (IV) are described, for example, in U.S. 
Pat. Nos. 3,028,365, 2,999,835, 3,148,172, 3,275,601, 2,991,273, 
3,271,367, 3,062,781, 2,970,131 and 2,999,846; in DE-OSS 1 570 703, 2 063 
050, 2 063 052 and 2 211 956; in German patent application P 38 32 396.6 
(Le A 26 344), in FR-PS 1 561 518 and in the monograph by H. Schnell 
entitled "Chemistry and Physics of Polycarbonates", Interscience 
Publishers, N.Y., 1964. 
Preferred diphenols (IV) are, for example, 4,4'-di-hydroxydiphenyl, 
2,2-bis-(4-hydroxyphenyl)-propane, 2,4-bis-(4-hydroxyphenyl)-2-methyl 
butane, 1,1-bis-(4-hydroxyphenyl)-cyclohexane, 
1,1-bis-(4-hydroxyphenyl)-3,3,5-trimethyl cyclohexane, .alpha., 
.alpha.'-bis-(4-hydroxyphenyl)-p-diisopropyl benzene, 
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-methyl butane, 
1,1-bis-(3,5-dimethyl-4-hydroxyphenyl)-cyclohexane, 
.alpha.,.alpha.'-bis-(3,5-dimethyl-4-hydroxyphenyl)-p-diisopropyl benzene, 
2,2-bis-(3,5-dichloro-4-hydroxyphenyl-propane and 
2,2-bis-(3,5-dibromo-4-hydroxyphenyl)-propane. 
Particularly preferred diphenols corresponding to formula (IV) are, for 
example, 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 and 
1,1-bis-(4-hydroxyphenyl)-3,3,5-trimethyl cyclohexane. 
The diphenols may be used both individually and also in admixture. 
Typical other chain terminators, i.e. known chain terminators for the 
synthesis of polycarbonates, are in particular low molecular weight chain 
terminators, i.e. phenolic compounds other than those corresponding to 
formula (I), such as for example phenol itself, or alkyl phenols, such as 
for example tert.-butylphenol or other C.sub.1-7 -alkyl-substituted 
phenols and, more particularly, those corresponding to formula (V) 
##STR5## 
in which R is a branched C.sub.8 and/or C.sub.9 alkyl radical. In the 
alkyl radical R, the percentage content of CH.sub.3 protons is between 47 
and 89% and the percentage content of CH and CH.sub.2 protons between 53 
and 11%; R is preferably in the o-and/or p-position to the OH group. More 
preferably, the upper limit to the ortho component is 20%. 
Other suitable typical chain terminators are halophenols, such as 
p-chlorophenol and 2,4,6-tribromophenol. These chain terminators are known 
from the literature. 
Accordingly, the polycarbonates or polycarbonate mixtures obtainable in 
accordance with the invention, in the production of which the preferred 
quantity of chain terminators (I) of 100% to 50% and, more particularly, 
100% to 75%, based on the total mol-% of chain terminators used, is used, 
preferably correspond to formula (VI) 
##STR6## 
in which --Z-- is as defined for formula (IV), 
p is an integer of 10 to 1,000 and preferably 30 to 80, 
E--O-- represents a unit corresponding to formula (Ia) 
##STR7## 
in which X, m, n, R.sub.1 and R.sub.2 are as defined for formula (I) and 
in which E'--O is either E--O-- or the residue of the typical other chain 
terminator mentioned above, i.e. in particular low molecular weight 
phenoxy groups other than (Ia); more particularly, at least half E'--O 
corresponds to the residue E--O; namely when (I) is used in quantities of 
100 to 75%, based on the total mol-% of chain terminator used. 
PRIOR ART 
Polymers with side groups on the backbone and polycarbonate chains grafted 
thereon are described in DE-OS 1 595 777. 
In our opposition to the corresponding DE-AS 1 595 777, we stated that, 
although the graft bases may also have an average functionality of less 
than 1, i.e. may be monofunctional, the patent department of the German 
patent office, in their decision of 20.2.83, clearly ruled out the 
presence of linear copolymers according to DE-AS 1 595 777. 
The polymers according to U.S. Pat. No. 3,687,895, DE-AS 1 770 144 or DE-OS 
1 770 144 (Le A 11 295) relate to polycarbonate chains grafted onto 
phenolic OH, at least five OH groups having to be present per molecule. 
Corresponding graft polycarbonates containing 3 to 10 side chains are known 
from DE-OS 2 357 192 (Le A 15 222). 
The radical polymerization of vinyl monomers in the presence of 
thermoplastic polycarbonates is also known (cf. for example U.S. Pat. No. 
3,462,515). If grafting reactions take place, it is not possible to define 
any specific point in the polycarbonate chain. In addition, the molecular 
weights of the graft-polymerized vinyl polymers are generally higher than 
those of anionically polymerized vinyl polymers. 
The reaction of allyl-terminated polycarbonates with vinyl compounds is 
described in Chem. Abstracts, Vol. 81, No. 4, 29th July, 1974, Ref. No. 13 
998a relating to Japanese patent application No. 70 121 553. The products 
obtained are transparent and soluble. 
According to DE-OS 2 702 626 (Le A 17 356), COOH-containing polymers 
containing 1 to 5 COOH groups are included in the polycarbonate synthesis. 
EP-PS 9 747 relates to branched, high molecular weight thermoplastic 
compounds which are made up of polycarbonate segments and polyether 
segments, being produced by polymerization of polycarbonates containing at 
least one unsaturated terminal group per molecule in the presence of a 
radically polymerizable monomer. 
Polyolefin carboxylic acids and their use for the production of 
polyolefin-polycarbonate block copolymers are known from DE-OS 3 618 378 
(Le A 24 330). 
Oligocarbonates containing unsaturated terminal groups are known from JA 
63/15 821 (only available as an abstract). 
Polycarbonate block copolymers are known from JA 63/15 822 (only available 
as an abstract), according to which vinyl and polycarbonate resins are 
produced in the presence of isopropenyl phenols and vinyl compounds are 
polymerized onto polycarbonate resins. 
Branched segment polymers are known from DE-OS 2 612 230 (Le A 17 926). 
Copolymers based on polycarbonates containing special terminal groups and 
polymers are known from JA 58/101 112 (only available as an abstract). 
Readily processable polycarbonate resins are known from JA 55/133 405 (only 
available as an abstract), being obtained by polymerization of unsaturated 
monomers in aqueous dispersion in the presence of polycarbonate granulate 
containing flow aids. 
Polycarbonate block copolymers obtained from polycarbonates and 
polymerizable monomers, the polycarbonates containing radical-forming 
groups, are known from JA 59/27 908 (only available as an abstract). 
According to Japanese patent application 61/051 015 (only available as an 
abstract), polycarbonate block copolymers are obtained by irradiation of 
polycarbonates containing benzoin structures in the presence of 
unsaturated monomers. 
Block copolymers having the structure polymethyl methacrylate - 
polycarbonate - polymethyl methacrylate are already known from U.S. Pat. 
No. 4,319,003, the polymethacrylate blocks having an M.sub.n (number 
average) of 500 to 35,000, the polycarbonate block having an M.sub.n 
(number average) of 500 to 30,000 and the block copolymers having an 
M.sub.n (number average) of 15,000 to 100,000. 
However, these block copolymers are produced in a different way, namely: 
the monofunctional polymethyl methacrylates are produced by radical 
polymerization, converted into monochloroformates and then reacted with 
polycarbonate diphenols in a ratio of 2:1. 
Disadvantages include a broad molecular weight distribution of the 
polycarbonate diphenols produced without chain terminators, a broad 
molecular weight distribution of the radically produced polymethyl 
methacrylates and the presence of non-incorporated polymethyl methacrylate 
segments in the block copolymer due to the generally known secondary 
reactions which accompany radical polymerizations or to the low reactivity 
of aliphatic OH groups during the conversion into the monochloroformates 
(cf. Schnell, Chemistry and Physics of Polycarbonates, Interscience 
Publishers, 1964, page 57, paragraphs 2 and 3). 
The polycarbonates or polycarbonate mixtures obtainable by the process 
according to the invention are either resistant to gasoline themselves 
where typical other chain terminators are predominantly used or, where 
chain terminators (I) were predominantly used, have the effect--when used 
as additives for other thermoplastic aromatic polycarbonates--of improving 
their resistance to gasoline. 
In the latter case, therefore, the gasoline-resistant polycarbonate molding 
compounds can be additionally varied by blending with other, separately 
produced polycarbonates and also through the choice of a different 
molecular weight or, better yet, a different degree of polymerization of 
the separately produced polycarbonate. 
Accordingly, the present invention also relates to the use of the 
polycarbonates or polycarbonate mixtures corresponding to formula (VI) 
obtainable in accordance with the invention [component B)] in quantities 
of 0.5% by weight to 30% by weight, preferably in quantities of 1% by 
weight to 12% by weight and more preferably in quantities of 2% by weight 
to 9% by weight, based on the total weight of component B) and other 
thermoplastic, aromatic polycarbonate [component A)], for improving the 
resistance of other thermoplastic, aromatic polycarbonates [component A)] 
to gasoline. 
Accordingly, the present invention also relates to polycarbonate molding 
compounds containing 0.5% by weight to 30% by weight, preferably 1% by 
weight to 12% by weight and, more preferably, 2% by weight to 9% by 
weight, based on the total weight of polycarbonate molding compound, of 
the polycarbonates or polycarbonate mixtures of formula (VI) obtainable in 
accordance with the invention [component B)] and 99.5% by weight to 70% by 
weight, preferably 99% by weight to 88% by weight and, more preferably, 
98% by weight to 91% by weight of other thermoplastic polycarbonates 
[component A)], the sum of components A) +B) being 100% by weight. 
Improving resistance to gasoline in this way is neither discussed nor 
suggested in U.S. Pat. No. 4,319,003. Instead, the resistance of 
thermoplastic polycarbonates to gasoline can be improved in various ways 
(cf. for example DE-OS 31 20 594, EP-PS 0 077 415, DE-OS 33 02 124, EP-OS 
0 131 196, DE-OS 33 47 071, DE-OS 36 28 258, DE-OS 37 12 116 and the prior 
art cited therein and, in addition, EP-PS 0 119 533, EP-OS 0 173 358 and 
EP-OS 0 186 825). 
However, the gasoline-resistant polycarbonate molding compounds according 
to the invention are neither described nor suggested in this prior art. 
Other thermoplastic aromatic polycarbonates of component A) according to 
the present invention are polycarbonates which contain no terminal groups 
corresponding to formula (Ia). 
The other thermoplastic aromatic polycarbonates of component A), of which 
the gasoline resistance is to be improved in accordance with the 
invention, are those based on diphenols corresponding to formula (VII) 
##STR8## 
in which Z is a single bond, a C.sub.1-8 alkylene group, a C.sub.2-12 
alkylidene group, a cyclohexylidene group, a 3,3,5-trimethyl 
cyclohexylidene group according to German patent application P 38 32 396.6 
(Le A 26 344), a benzylidene group, a methyl benzylidene group, a 
bis-(phenyl)-methylene group, --S--, --SO.sub.2 --, --CO-- or --O--, 
with weight average molecular weights M.sub.w (as determined in known 
manner via the relative solution viscosity) in the range from 15,000 to 
120,000, preferably in the range from 20,000 to 80,000 and more preferably 
in the range from 25,000 to 45,000. 
Suitable diphenols (VII) are listed above under the diphenols (IV); the 
same also applies to the preferred and particularly preferred diphenols 
(VII). 
However, other preferred diphenols corresponding to formula (VII) are those 
in which --Z-- contains a polymeric siloxy group and which correspond to 
formula (VIIa) 
##STR9## 
in which R is C.sub.1-4 alkyl, preferably CH.sub.3, and 
n has a value of 20 to 100 and preferably 40 to 80. 
Suitable diphenols corresponding to formula (VIIa) are, for example, those 
corresponding to formula (VIIb) 
##STR10## 
in which n has a value of 40, 60 or 80. 
The polycarbonates of component A) are both homopolycarbonates and also 
copolycarbonates, the diphenols (VIIa) or (VIIb) being incorporated in the 
polycarbonates by condensation in quantities of at most 20% by weight, 
based on the molar sum of all the diphenols (VII)+(VIIa) or (VIIb) to be 
used. 
The polycarbonates of component A) may be linear or even branched. 
If desired, small quantities, preferably quantities of 0.05 to 2.0 mol-% 
(based on mols diphenols used), of trifunctional or more than 
trifunctional compounds, more particularly those containing three or more 
than three phenolic hydroxyl groups, are used as branching agents to 
obtain branched polycarbonates. Some of the compounds containing three or 
more than three phenolic hydroxyl groups which may be used as branching 
agents are phloroglucinol, 
4,6-dimethyl-2,4,6-tri-(4-hydroxyphenyl)-hept-2-ene, 
4,6-dimethyl-2,4,6-tri-(4-hydroxyphenyl)-heptane 
1,3,5-tri-(4-hydroxyphenyl)-benzene,1,1,1-tri-(4-hydroxyphenyl)-ethane, 
tri-(4-hydroxyphenyl)-phenyl methane, 
2,2-bis-(4,4-bis-(4-hydroxyphenyl)-cyclohexyl)-propane, 
2,4-bis-(4-hydroxyphenylisopropyl)-phenol, 
2,6-bis-(2-hydroxy-5'-methylbenzyl)-4-methylphenol, 
2-(4-hydroxyphenyl)-2-(2,4-dihydroxyphenyl)-propane, 
hexa-(4-(4-hydroxyphenylisopropyl)-phenyl)-orthoterephthalic acid ester, 
tetra-(4-hydroxyphenyl)-methane, 
tetra-(4-(4-hydroxyphenylisopropyl)-phenoxy)-methane and 
1,4-bis-(4',4"-dihydroxytriphenyl)-methyl)-benzene. 
Some of the other trifunctional compounds are 2,4-dihydroxybenzoic acid, 
trimesic acid, cyanuric chloride and 
3,3-bis-(3-methyl-4-hydroxyphenyl)-2-oxo-2,3-dihydroindole. 
Suitable chain terminators for regulating the molecular weights of the 
polycarbonates of component A) are the chain terminators typically used in 
the synthesis of polycarbonates, more particularly low molecular weight 
chain terminators, i.e. other phenolic compounds than those corresponding 
to formula (I), of the type already described for the production of the 
polycarbonates according to the invention of component B). 
The polycarbonates of component A) are either known from the literature or 
are the subject of German patent applications P 38 32 396.6 (Le A 26 344) 
and P 38 42 931.4 (Le A 26 318) or may be produced by known methods. 
The polycarbonates of component A) may be used both individually and in 
combination with one another. 
To produce the polycarbonate molding compounds according to the invention 
from the polycarbonates or polycarbonate mixtures of formula (VI) 
according to the invention [component B)] and the other polycarbonates of 
component A), the components may be mixed in the particular ratio desired 
above the softening temperature of the other thermoplastic aromatic 
polycarbonates used as component A). 
This may be done in a single step, for example by compounding during 
extrusion in standard screw extruders, for example at temperatures in the 
range from 280.degree. to 350.degree. C. Known machines are suitable for 
compounding. Twin screw extruders are preferably used. 
The polycarbonate molding compounds according to the invention may also be 
produced by mixing solutions of the polycarbonates of component B) with 
solutions of the polycarbonates of component A), followed by evaporation 
of the solvents, for example in an extruder, and subsequent granulation or 
other isolation. 
Accordingly, the present invention also relates to a process for the 
production of the polycarbonate molding compounds according to the 
invention containing as component A) 
70% by weight to 99.5% by weight, preferably 88% by weight to 99% by weight 
and more preferably 91% by weight to 98% by weight of the thermoplastic 
aromatic polycarbonates in question 
and as component B) 
30% by weight to 0.5% by weight, preferably 12% by weight to 1% by weight 
and, more preferably, 9% by weight to 2% by weight of the polycarbonates 
or polycarbonate mixtures of formula (VI) obtainable in accordance with 
the invention, 
the total weight of A)+B) being 100% by weight, characterized in that 
either components A) and B) are mixed above the softening temperature of 
component A) and the resulting mixture is subsequently isolated in known 
manner or solutions of component A) are mixed with solutions of component 
B) and the resulting mixture is subsequently isolated in known manner by 
evaporation of the solvents. 
A suitable solvent for the polycarbonate component A) is, for example, 
CH.sub.2 Cl.sub.2 ; a suitable solvent for component B) is, for example, 
methylene chloride or chlorobenzene. 
The stabilizer systems and/or mold release agents typical of polycarbonate 
or poly(meth)acrylates may of course be used as required in polymer 
mixtures of the type in question, being incorporated in known manner by 
compounding as described above. 
To determine resistance to gasoline, test specimens measuring 80 
mm.times.10 mm.times.4 mm were made up and fixed to flexible templates 
having different radii of curvature in such a way that outer fiber strains 
.epsilon..sub.R of 0.3% and 1.0% were obtained. The templates together 
with the test specimens were stored in a heating cabinet (with air 
circulation; DIN 50 011, 2, 3) for 15 minutes at 70.degree. C. 
The templates together with the test specimens were then removed from the 
heating cabinet and a cotton wool plug impregnated with a test fuel was 
applied immediately afterwards. The test fuel used was a white spirit 
according to DIN 51 604 which consists of 50% by volume toluene, 30% by 
volume isooctane, 15% by volume diisobutylene and 5% by volume ethanol. 
After a contact time of 15 minutes, the cotton wool plug was removed and 
the test specimen was left for another 15 minutes to air. 
The test specimens were then evaluated with the naked eye on the basis of 
the following scale: 
______________________________________ 
Stage Feature 
______________________________________ 
1 No visible change 
2 Surface matted 
3 Fine cracks 
4 Large cracks, fracture 
______________________________________ 
The improved impact strength was also determined on test specimens 
measuring 80 mm.times.10 mm.times.4 mm. Izod notched impact strength 
(a.sub.k) was determined in accordance with ISO 180/1A. The results of the 
performance tests are shown in the following Table. A 
p-tert.-butylphenoxyterminated bisphenol A polycarbonate having an 
.eta..sub.rel value of 1.290 and a p value of 55.5 was tested for 
comparison (Example 6).

EXAMPLES 
EXAMPLE 1 
a) Preparation of a compound of formula (I) in which n=O, R.sub.1 =H and 
R.sub.2 =C.sub.4 H.sub.9 
3.5 1 anhydrous toluene were introduced under nitrogen into a thoroughly 
heated 12 liter autoclave equipped with a paddle stirrer. 1.5 kg butyl 
acrylate distilled over calcium hydroxide and 19.5 g dried zinc iodide are 
then added. The autoclave is purged three times with nitrogen and cooled 
to 0.degree. C. 90 g bis-trimethylsilyl monothiohydroquinone are then 
added and the reaction mixture is stirred for 20 hours at 0.degree. C. The 
reaction is then stopped by addition of 150 ml methanol. 
The solution is introduced into a column filled with Al.sub.2 O.sub.3 and, 
after the addition of 50 ml concentrated hydrochloric acid and 150 ml 
methanol, the silyl groups are eliminated for 3 hours at 80.degree. C. 
The yield after evaporation in a rotary evaporator was approximately 1,300 
g. 
The average molecular weight M.sub.n, as determined by gel permeation 
chromatography, was 14,100 (m=110) g/mol and the polydispersity D was 
1.09. 
b) Polycarbonate containing terminal groups corresponding to formula (Ia) 
15 g (0.15 mol) phosgene are introduced over a period of 15 minutes with 
stirring at 20.degree. to 25.degree. C. into a mixture of 22.8 g(0.10 mol) 
2,2-bis-(4-hydroxyphenyl)-propane (BPA), 20 g sodium hydroxide (0.50 mol), 
400 ml water and 42.3 g (=3 mol-%, based on BPA) of the polybutyl acrylate 
described in a) dissolved in 600 ml methylene chloride. 0.14 ml (=1 mol-%, 
based on BPA) N-ethyl piperidine is then added, followed by stirring for 1 
hour. The organic phase is separated off, washed until free from 
electrolyte and dried at 80.degree. C. after removal of the methylene 
chloride by distillation. 65 g of product having a relative solution 
viscosity .eta..sub.rel of 1.248 were obtained. 
The aromatic polycarbonate block has a molecular M.sub.n of 16,600 g/mol 
(as determined by gel permeation chromatography), corresponding to a 
degree of polycondensation p of 65.3. The total molecular weight M.sub.n 
of the block copolymer, including the terminal groups, is 44,800 g/mol. 
EXAMPLE 2 
Polycarbonate containing terminal groups corresponding to formula (Ia) 
15 g (0.15 mol) phosgene are introduced with stirring over a period of 1 
hour at 20.degree. to 25.degree. C. into a mixture of 22.8 g (0.10 mol) 
2,2-bis-(4-hydroxyphenyl)-propane (BPA), 20 g sodium hydroxide (0.5 mol), 
400 ml water and 14.1 g (=1 mol-%, based on BPA) of the polybutyl acrylate 
described in a) dissolved in 600 ml methylene chloride. 0.14 ml (=1 mol-%, 
based on BPA) N-ethyl piperidine is then added, followed by stirring for 1 
hour. The organic phase is separated off, washed until free from 
electrolyte and the block copolymer is dried at 80.degree. C. after 
removal of the methylene chloride by distillation. 37 g of product having 
a relative solution viscosity .eta..sub.rel of 1.464 were obtained. 
The aromatic polycarbonate block has a molecular weight M.sub.n of 22,600 
g/mol, corresponding to a degree of polycondensation p of 89. The total 
molecular weight of the block copolymer, including the terminal groups, is 
50,800 g/mol. 
EXAMPLE 3 
Polycarbonate containing terminal groups corresponding to formula (Ia) and 
a terminal 4-tert.-butylphenoxy group 
15 g (0.15 mol) phosgene are introduced with stirring over a period of 1 
hour at 20.degree. to 25.degree. C. into a mixture of 22.8 g (0.10 mol) 
2,2-bis-(4-hydroxyphenyl)-propane (BPA), 20 g sodium hydroxide (0.5 mol); 
400 ml water, 0.225 g (=1.5 mol-%, based on BPA) 4-tert.-butylphenol and 
21.65 g (=1.5 mol-%, based on BPA) of the polybutyl acrylate described in 
a) dissolved in 600 ml methylene chloride. 0.14 ml (=1 mol-%, based on 
BPA) N-ethyl piperidine is then added, followed by stirring for 1 hour. 
The organic phase is separated off, washed free from electrolyte and the 
block copolymer is dried at 80.degree. C. after removal of the methylene 
chloride by distillation. 42 g product having a relative solution 
viscosity .eta..sub.rel of 1.258 were obtained. 
The aromatic polycarbonate block has a molecular weight M.sub.n of 14,200 
g/mol, corresponding to a degree of polycondensation p of 56. The total 
molecular weight of the block copolymer, including the terminal groups, is 
28,300 g/mol. 
EXAMPLE 4 
Mixing by melt compounding 
93.4 Parts of a polycarbonate (PC) of bisphenol A having a relative 
solution viscosity .eta..sub.rel of 1.290 (as measured in methylene 
chloride, 5 g/l, at 25.degree. C.) and 6.6 parts of the block copolymer 
(corresponding to 4 parts butyl acrylate block) of Example lb) were mixed 
by compounding at 270.degree. to 290.degree. C. in a ZSK 32. 
EXAMPLE 5 
In situ blend production 
2.7 kg (27 mol) phosgene are introduced with stirring over a period of 1 
hour at 20.degree. to 25.degree. C. into a mixture of 4.56 kg (20 mol) 
2,2-bis-(4-hydroxyphenyl)-propane (BPA), 99.8 g (=3.4 mol-%, based on BPA) 
p-tert.-butylphenol, 8 kg sodium hydroxide (w=45%), 40 1 water, 12 kg 
chlorobenzene and 250 g (=4% by weight, based on the total weight of the 
polycarbonate produced) of the polybutyl acrylate described in Example la) 
dissolved in 37 kg methylene chloride. 28 ml (=1 mol-%, based on BPA) 
N-ethyl piperidine are then added, followed by stirring for 1 hour. The 
organic phase is separated off, washed until free from electrolyte and 
extruded at 280.degree. C. after removal of the methylene chloride by 
distillation. 3.7 kg product having a relative solution viscosity 
.eta..sub.rel of 1.292 were obtained. The polycarbonate-co-butyl acrylate 
has a molecular weight M.sub.n of 28,000 g/mol, corresponding to a degree 
of polycondensation of the aromatic polycarbonate block of 54.7. The 
percentage content of conventional p-tert.-butyl phenyl-terminated 
bisphenol A polycarbonate of component A) is 90.5% by weight (97.4 mol-%). 
TABLE 
______________________________________ 
Eamples 
4 5 6 
______________________________________ 
Properties 
a.sub.k (kJ/m.sup.2) 
+23.degree. C. 
719 749 802 
+0.degree. C. 658 743 348 
-10.degree. C. 
387 388 226 
-20.degree. C. 
239 247 -- 
-30.degree. C. 
-- -- -- 
-40.degree. C. 
-- -- -- 
Gasoline resistance 
1st cycle 
E = 0.3% 2 2 4 
E = 1.0% 2 2 -- 
2nd cycle 
E = 0.3% 2 2 -- 
E = 1.0% 2 2 -- 
______________________________________