Epitaxial crystallization and solid hot-drawing technology were employed to fabricate oriented homo-epitaxial crystallization of polylactic acid (PLA) with nano-topography to enhance its blood compatibility and mechanical characteristics as blood-contacting medical devices. The process involved solid hot stretching the PLA plates. A PLA nutrient solution was then used to immerse the oriented plates to dissolve some of the PLA solutes, ensuring plate integrity. Consequently, the drawing process exponentially enhanced the modulus and tensile strength of the PLA. Orientation and epitaxial crystallization could substantially enhance blood compatibility of PLA by prolonging clotting time and decreasing hemolysis rate, protein adsorption, and platelet activation. The oriented homo-epitaxial crystallization of PLA exhibited a nanotopography and fibrous structure similar to the intimal layer of a blood vessel, and this biomimetic structure was advantageous in decreasing the activation and/or adhesion of platelets.

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This study prepared layered intumescent flame retardant (IFR)‐graphene oxide (GO) via the esterification of GO and IFR. Then the distribution of IFR‐GO in polybutylene terephthalate (PBT) was regulated via an injection molding process, while the tensile strength and combustion were explored. The results showed that the flame retardant distribution in PBT presented high external concentrations and low internal concentrations when the injection time was reduced. The lowest flame retardant content of 20 wt% was evident at an injection time of 2 s while displaying a high limiting oxygen index of 27.1. Although this resulted in a V‐0 flame‐retardant level, the mechanical properties were not affected. Therefore, the flame retardant was proportionately reduced by a shorter injection time to form a concentration gradient core‐shell‐like macrostructure, significantly increasing the flame‐resistant efficiency while retaining the mechanical properties.