After OPPO Find N4 folding screen mobile phone has undergone 100,000 opening and closing tests, its hinge bracket still maintains a precise positioning of 0.01mm. The secret is hidden in the microphase separation structure of Sinopec’s SCG®-PC/TPU alloy. This innovative material uses TPU elastomer island dispersion technology to increase the impact strength to 85kJ/m² (ordinary PC is only 25kJ/m²), and zirconium-based liquid metal reinforcement increases the Mohs hardness to 5.2. The most revolutionary is the self-healing coating technology: the surface polyrotaxane microcapsules automatically repair scratches at 60°C, reducing the cost of the whole machine by 40% compared with Samsung’s stainless steel solution. Honor Magic V3 followed closely and adopted this technology, driving the domestic folding screen hinge material market size to exceed 5 billion yuan in 2025. In the upstream of the industrial chain, Green Cycle’s 30% marine recycled PET modified PC alloy has passed UL Ecologo certification, reducing carbon footprint by 34% and applied to the vivo X Fold4 frame. Lotte Chemical’s HP-1000XA alloy is rewriting the standard for micro-injection molding of electronic connectors with its excellent fluidity at high temperatures of 220°C, achieving precision molding with a wall thickness of 0.25mm. As the localization process of Apple Vision Pro accelerates, these engineering plastics hidden in the folding mechanism are becoming invisible weapons to compete with international giants.
