Influence of Matrix Selection and Drawing Conditions on TLCP Reinforcement in High‐Modulus Composites for Material Extrusion Additive Manufacturing

ABSTRACT Vectra B950 (VB950) was co‐extruded with polyamide 6 (PA6) and poly(etherimide) (PEI) to compare reinforcement development in matrices with contrasting rheological responses and thermal processing requirements. Within the investigated compositions, the tensile modulus of VB950–PA6 composites increased with nominal draw ratio (set by die diameter), whereas VB950–PEI composites showed little draw‐ratio dependence. Filament tensile moduli reached 28.6 GPa (48 wt% TLCP) for the PA6 system and 45 GPa (91 wt% TLCP) for the PEI system. Complex viscosity ratios provided a comparative, oscillatory‐based framework for interpreting these responses, and microscopy confirmed fibrillar TLCP morphology. Overlapping thermal processing windows additionally enabled fabrication of TLCP–PEI filaments in a single extruder. The composites were subsequently processed by fused filament fabrication. Printing reduced the tensile modulus relative to the as‐extruded filaments by 17%–55% for TLCP–PEI composites while printed moduli reached 34.8 GPa along the raster direction. These findings provide processing guidance on material selection, extrusion temperature, draw‐down, and printing temperature for developing and retaining TLCP reinforcement in filament generation and material extrusion additive manufacturing.