Study on crystallization behavior and microstructure regulation of liquid crystal polymer films fabricated by rotational film blowing

Abstract Liquid crystal polymer (LCP) has become an ideal material for 5G communication due to its characteristics such as low dielectric constant ( D k ), low dielectric loss (D f ), high mechanical strength and excellent thermal resistance. This study establishes rotational blow molding as an innovative microstructure engineering platform for LCP films. By combining DSC, XRD, polarizing optical microscopy and polarized infrared spectroscopy, the rotational shearing driven regulation of molecular chain alignment and its effects on crystalline morphology were systematically analyzed. We demonstrated programmable molecular alignment control, identifying a critical transition at 20 rpm that generates a unique cross‐weaving network. This distinctive architecture reduces the crystallinity of the film products, simultaneously enhances mechanical toughness (300% increase in elongation) and promotes isotropy while maintaining excellent 5G dielectric properties. The established processing structure–property relationship provides fundamental insights for microstructure design of high‐performance polymer films in advanced communication applications. © 2025 Society of Chemical Industry.