<p>Understanding the physical behavior of polymers during processing is crucial for developing new materials suitable for emerging technologies. Rotational molding (RM), a low-shear manufacturing method, requires a distinct approach to material characterization, as polymer behavior under these conditions differs from that observed in conventional melt mixing and laboratory-scale molding techniques. This study investigated the miscibility of poly(lactic acid) (PLA) and poly(ethylene 2,5-furandicarboxylate) (PEF) blends. The RM processability of bio-polymeric blends was evaluated using dry-blending and melt-mixing procedures. The influence of the multi-stage preparation procedure for PLA-PEF blends on melt-mixed RM was verified. The blends containing up to 50 wt% PEF exhibited good RM-processability, and the introduction of 25 wt% PEF enabled the manufacture of a product with a uniform RM-part wall structure. Moreover, it was demonstrated that the fine, dispersed structure of the pre-extruded blends could be preserved despite partial coalescence and structural relaxation of the polymers during cryogenic grinding and the subsequent long-duration RM process. Correlated rheological, structural, thermal, and thermomechanical analyses enabled a comprehensive description of the phenomena and limitations, providing support for the further upscaling of novel thermoplastic bio-polyester blends. This work addresses the knowledge gap on forming polymeric blends under shaping conditions in RM technology based on polymer sintering, with almost complete exclusion of shear forces during processing.</p> Graphical abstract <p></p>