US 12,590,200 B2 · Polyester compositions including carbon nanotubes as microwave absorbers in sensor applications

Abstract

Thermoplastic compositions include: a thermoplastic polymer component including a polyester; and from greater than 0.10 wt % to about 1.95 wt % of a carbon nanotube (CNT) fdler. A 6 in×8 in×⅛ in molded sample of the composition has a percent Absorbed Power measured in Transmission mode of at least 60% when observed at a 77 GHz frequency according to a Free Space method. In some aspects the polyester includes polybutylene terephthalate (PBT). Further aspects include articles (e.g., a radar sensor, a camera, an electronic control unit, etc.) including a molded part including a microwave absorbing material (absorber). The article may have at least two openings to allow the transmission of microwave radiation between a transmitting antenna and a receiving antenna located in/on the printed circuit board of the sensor.

Claims15

Dependent claims

A thermoplastic composition comprising:

a thermoplastic polymer component comprising a polyester;
a polycarbonate-siloxane copolymer, and
from greater than 0.10 wt % to about 1.95 wt % of a carbon nanotube (CNT) filler,
wherein the CNT filler has an average diameter of about 5-15 nanometers (nm), a surface area of at least 100 square meters per gram (m2/g), and a volume resistivity less than 10−3 Ohm·centimeters (Ω·cm),
wherein a 6 inch (in)×8 in×⅛ in molded sample of the composition has a percent Absorbed Power measured in Transmission mode of at least 60% when observed at a 77 GHz frequency according to a Free Space method, and
wherein the composition has a notched Izod impact (NII) strength of at least 102 Joules per meter (J/m) at −30° C. as tested in accordance with ASTM D256 and ASTM D4812.

3 more elements

Dependencies are inferred from the claim text.

Polyester compositions including carbon nanotubes as microwave absorbers in sensor applications

Life of this patent

Polyester compositions including carbon nanotubes as microwave absorbers in sensor applications

Life of this patent

Abstract

Claims15