Stabilization of polycarbonates
View Patent ↗The invention relates to the use of a specific hindered amine (hindered amine light stabilizer, HALS) and a specific bismalonate UV absorber for the stabilization of polycarbonates and of polycarbonate blends, in particular of polycarbonate/acrylonitrile-butadiene-styrene (PC/ABS) blends, with respect to UV radiation.
1. A masterbatch Z comprising a component A, a component B and a component C and optionally a component D, where component A is a compound of the formula (I)
component C is one or more polymers selected from the group consisting of polycarbonates, and
of blends composed of polycarbonate and of one or more polymers other than polycarbonate;
and of polymers compatible with polycarbonates, these polymers compatible with polycarbonates being selected from the group consisting of acrylonitrile-butadiene-styrene, styrene-acrylonitrile and polystyrene;
component B being a compound of formula (III)
and component D being a UV stabilizer.
2. The masterbatch Z according to claim 1 , where component D is a compound selected from the group consisting of compounds of the formulae (II), (IV), (V), (VI), (VII), (VIII), (IX), (X) and (XI).
3. The masterbatch Z according to claim 1 , wherein the masterbatch Z is free from effective amounts of further hindered amine light stabilizer HALS with a chemical structure other than the structure of the compound of the formula (I).
4. The masterbatch Z according to claim 1 , comprising
from 0.01 to 30% by weight of component A,
from 20 to 99.98% by weight of component C,
from 0.01 to 30% by weight of component B, and
from 0 to 79.98% by weight of further substances;
the % by weight values being based in each case on the total weight of the masterbatch Z; where the % by weight values for components A, B and C and for the further substances always give a total of 100% by weight.
5. The masterbatch Z according to claim 1 , where the ratio by weight of component A to component B in the composition Z is from 1:10 to 10:1.
6. A process for the preparation of a masterbatch Z, comprising the step of physically mixing components A, B and C and optionally further substances, wherein the masterbatch Z comprises a component A, a component B and a component C and optionally a component D, where
component A is a compound of the formula (I)
component C is one or more polymers selected from the group consisting of polycarbonates, and
of blends composed of polycarbonate and of one or more polymers other than polycarbonate;
and of polymers compatible with polycarbonates, these polymers compatible with polycarbonates being selected from the group consisting of acrylonitrile-butadiene-styrene, styrene-acrylonitrile and polystyrene;
component B being a compound of formula (Ill)
and component D being a UV stabilizer.
7. The process according to claim 6 , where the mixing is done via extrusion, kneading, injection moulding or compression moulding.
8. The process according to claim 6 , where the mixing temperature is from 100° C. to 380° C.
9. The process according to claim 6 , wherein the mixing time is from 10 sec to 1 h.
10. A method of using masterbatch Z, for the preparation of, or as, stabilized polycarbonate polymer or stabilized polycarbonate blend, wherein the masterbatch Z comprises a component A, a component B and a component C and optionally a component D, where
component A is a compound of the formula (I)
component C is one or more polymers selected from the group consisting of polycarbonates, and
of blends composed of polycarbonate and of one or more polymers other than polycarbonate;
and of polymers compatible with polycarbonates, these polymers compatible with polycarbonates being selected from the group consisting of acrylonitrile-butadiene-styrene, styrene-acrylonitrile and polystyrene;
component B being a compound of formula (Ill)
and component D being a UV stabilizer.