a thermoplastic filament comprising multiple polymers of differing flow temperatures in a regular geometric arrangement , and a method for producing such a filament , are described . because of the difference in flow temperatures , there exists a temperature range at which one polymer is mechanically stable while the other is flowable . this property is extremely useful for creating thermoplastic monofilament feedstock for three - dimensionally printed parts , wherein the mechanically stable polymer enables geometric stability while the flowable polymer can fill gaps and provide strong bonding and homogenization between deposited material lines and layers . these multimaterial filaments can be produced via thermal drawing from a thermoplastic preform , which itself can be three - dimensionally printed . furthermore , the preform can be printed with precisely controlled and complex geometries , enabling the creation of monofilament and fiber with unique decorative or functional properties .