Melt processable thermoplastic composite comprising a multimodal dielectric filler

A melt-processable thermoplastic composite comprises 10-90 vol.% thermoplastic polymer, 10-90 vol.% dielectric filler, and 0.5-5 vol.% flow modifier, wherein the composite has a dielectric constant of ≥5 and a dielectric loss of ≤0.007 at 500 MHz to 10 GHz. The thermoplastic polymer comprises poly(aryl)etherketone, polysulphone, poly(phenylene sulphide), poly(ether imide), poly(amide imide), fluoropolymer, polyolefin, polystyrene, poly(phenylene ether), or liquid crystalline polymer. The dielectric filler has a multimodal particle size distribution comprising first particles with a first size and second particles having a second size, wherein the first size is 10-20 times that of the second size. The dielectric filler comprises titanium dioxide, silica, boron nitride, barium or strontium titanate, corundum, wollastonite, aluminium oxide or nitride, silicon carbide, beryllia, or magnesia. An article, e.g. an antenna, comprising the composite is also disclosed. A method of forming an article comprising injection moulding, extruding, or layer-by-layer printing the composite is further claimed.