IR reflective elements made of impact-resistance plastic, and a process for their production
A process for the production of a translucent, IR-reflective plastic element, consisting entirely or at least in part of an impact-resistant, thermoplastic plastic, containing IR-reflective particles made of a lamellar-shaped carrier pigments coated with a metal oxide and the plastic element made therefrom.
1. A process for the manufacturing a roof or a face of a building, comprising:
constructing said roof from a plastic element which comprises an impact-resistant, thermoplastic plastic, and from 0.01 to 2 wt. % of IR-reflective particles comprising lamellar-shaped carrier pigments coated with a metal oxide,
wherein said element is a double-web plate;
wherein the plastic element is made by a process comprising:
mixing said IR-reflective particles with a melt of a low-viscosity thermoplastic plastic at a temperature of at least 280° C. in a pressure-free, non-shearing zone of a twin-screw extruder to form a pre-mixture comprising from 5 to 40 wt. % of said IR-reflective particles;
extruding said pre-mixture;
converting said pre-mixture to granulate form or a melt;
mixing said granulate or melt of the premixture with a granulate or a melt of a polymethyl methacrylate modified to be impact-resistant to form a plastic mixture wherein said polymethyl methacrylate comprises a polymer matrix and an agent to modify impact resistance;
extruding or co-extruding the resultant plastic mixture with a melt of a thermoplastic plastic into an extrudate having a desired shape; and
cooling said extrudate.
2. A roof or a face of a building, comprising:
a plastic element which comprises an impact-resistant, thermoplastic plastic, and from 0.01 to 2 wt. % of IR-reflective particles comprising lamellar-shaped carrier pigments coated with a metal oxide,
wherein said element is a double-web plate;
wherein the plastic element is made by a process comprising:
mixing said IR-reflective particles with a melt of a low-viscosity thermoplastic plastic at a temperature of at least 280° C. in a pressure-free, non-shearing zone of a twin-screw extruder to form a pre-mixture comprising from 5 to 40 wt. % of said IR-reflective particles;
extruding said pre-mixture;
converting said pre-mixture to granulate form or a melt;
mixing said granulate or melt of the premixture with a granulate or a melt of a polymethyl methacrylate modified to be impact-resistant to form a plastic mixture wherein said polymethyl methacrylate comprises a polymer matrix and an agent to modify impact resistance;
extruding or co-extruding the resultant plastic mixture with a melt of a thermoplastic plastic into an extrudate having a desired shape; and
cooling said extrudate.
3. A building, comprising the roof or face of a building according to claim 2 .
4. A method of producing a building, comprising
constructing said building from the roof or face of a building according to claim 2 .
5. The process according to claim 1 wherein said carrier pigment is coated with alternating layers of metal oxide.
6. The process according to claim 1 wherein said carrier pigment is coated with alternating layers of metal oxide;
wherein a difference of the index of refraction between two alternation layers is at least 0.1.
7. The process according to claim 1 wherein said carrier pigment is coated with a layer of metal oxide having a thickness of 90 to 150 nm.
8. The process according to claim 1 , wherein said element is resistant to hail.
9. The process according to claim 1 , wherein said element is resistant to polyamide balls with a diameter of approximately 20 mm having at least 4 J of energy.
10. The process according to claim 1 , wherein said plastic element comprises from 0.1 to 2 wt. % of said IR-reflective particle.
11. The process according to claim 1 , wherein said plastic element comprises a white pigment.
12. The process according to claim 11 , wherein said white pigment is present at an amount ranging from 0.5 to 5 wt. %.
13. The process according to claim 1 , wherein said plastic element is a flat sheet or a hollow element.
14. The roof or a face of a building according to claim 2 , wherein said carrier pigment is coated with alternating layers of metal oxide.
15. The roof or a face of a building according to claim 2 , wherein said carrier pigment is coated with alternating layers of metal oxide;
wherein a difference of the index of refraction between two alternation layers is at least 0.1.
16. The roof or a face of a building according to claim 2 , wherein said carrier pigment is coated with a layer of metal oxide having a thickness of 90 to 150 nm.
17. The roof or a face of a building according to claim 2 , wherein said element is resistant to hail.
18. The roof or a face of a building according to claim 2 , wherein said element is resistant to polyamide balls with a diameter of approximately 20 mm having at least 4 J of energy.
19. The roof or a face of a building according to claim 2 , wherein said plastic element comprises from 0.1 to 2 wt. % of said IR-reflective particle.
20. The roof or a face of a building according to claim 2 , wherein said plastic element comprises a white pigment.
21. The roof or a face of a building according to claim 20 , wherein said white pigment is present at an amount ranging from 0.5 to 5 wt. %.
22. The roof or a face of a building according to claim 2 , wherein said plastic element is a flat sheet or a hollow element.