Polymer composition with heat-absorbing properties and high stability
The present invention relates to a heat-absorbing polymer composition containing a transparent thermoplastic synthetic substance, an inorganic infrared absorber with stabilizer and also to the production and use of the polymer compositions according to the invention and to the products produced therefrom. In particular, the present invention relates to the stabilization of inorganic IR absorbers from the group of the tungsten compounds and also to the use of the polymer composition according to the invention containing these stabilized inorganic IR absorbers for the purpose of producing windowpanes for use in buildings, motor vehicles, rail vehicles or aircraft.
1. A polymer composition comprising:
a) a transparent thermoplastic synthetic substance;
b) an inorganic IR absorber comprising caesium tungstate; and
c) a phosphine-based stabiliser;
wherein the phosphine-based stabiliser comprises a compound selected from the group consisting of triphenylphosphine, trialkylphenylphosphine, bisdiphenylphosphinoethane, trinaphthylphosphine, and mixtures thereof and is present in an amount of from 0.01 wt. % to 0.20 wt. %, relative to the overall composition.
2. The composition according to claim 1 , wherein the infrared absorber with a solids content based on tungstate is present in an amount of from 0.0001 wt. %-10 wt. %, relative to the overall composition.
3. The composition according to claim 1 , wherein the transparent thermoplastic synthetic substance is selected from the group consisting of polymethyl methacrylates, polycarbonates, and copolycarbonates.
4. The composition according to claim 1 , wherein the composition comprises at least one further IR absorber.
5. The composition according to claim 4 , wherein said at least one further IR absorber is selected from the group consisting of borides and tin oxides.
6. The composition according to claim 1 , wherein the composition further comprises a compound selected from the group consisting of ultraviolet absorbers, colouring agents, mould-release agents, flameproofing agents, thermostabilisers, and combinations thereof.
7. A master batch comprising
a) from 85.00 wt. % to 98.89 wt. % of a transparent thermoplastic synthetic substance;
b) from 0.1 wt. % to 2.0 wt. % of an inorganic IR absorber comprising tungstate;
c) from 1.0 wt. % to 4.8 wt. % of a dispersing agent;
d) from 0.01 wt. % to 0.20 wt. % of a phosphine-based stabiliser;
e) from 0 to 8.0 wt. % of at least one further auxiliary substance and/or additive;
wherein, the sum of components a) through e) add up to 100 wt. %.
8. The master batch according to claim 7 , wherein the transparent thermoplastic synthetic substance is present an amount of 93.00 wt % to 98.89 wt. %.
9. The master batch according to claim 7 , wherein the inorganic IR absorber comprising tugnstate is Cs 0.33 WO 3 .
10. The master batch according to claim 7 , wherein the phosphine-based stabiliser is triphenylphoshine.
11. The master batch according to claim 7 , wherein the at least one further auxiliary substance and/or additive comprises zirconium dioxide.
12. The master batch according to claim 7 , wherein the inorganic IR absorber is present in an acrylate matrix; the transparent thermoplastic synthetic substance is a polycarbonate; and the stabiliser is triphenylphosphine.
13. A polymer composition comprising:
a) a transparent thermoplastic synthetic substance;
b) an inorganic IR absorber comprising tungstate;
c) a phosphine-based stabiliser; and
d) a phosphite-based stabiliser.
14. An automobile glazing or an architectural glazing comprising the polymer according to claim 1 .
15. A process for producing a polymer composition, comprising:
a) producing a master batch comprising:
i) a transparent thermoplastic synthetic substance;
ii) an IR absorber comprising a tungstate in an acrylate matrix; and
iii) a phosphine-based stabiliser;
b) mixing the master batch in an extruder, wherein the transparent thermoplastic synthetic substance is fused during mixing.
16. The polymer composition of claim 1 , wherein the phosphine-based stabiliser stabilises the inorganic IR absorber comprising caesium tungstate.