Based on the structural characteristics of plastic products, materials can be precisely matched from the following dimensions, balancing performance, processing feasibility, and cost control:
Matching Materials According to Core Structural Features
Thin-walled Structures: These structures require materials with excellent flowability to quickly fill narrow cavities during injection molding. Prioritize low molecular weight, high flow properties materials, such as PS and low melt index ABS. High-flow PP can also be used for some thin-walled food containers to avoid defects such as insufficient glue or flow marks.
Thick-walled/Large-size Structures: These structures require strict control of shrinkage deformation. Prioritize materials with low shrinkage rates, such as ABS and PC. Avoid using materials with high crystallinity and high shrinkage rates, such as PP and PA, to prevent shrinkage cavities and depressions in thick-walled areas.
Precision Load-bearing Structures (e.g., gears, clips): These structures have high requirements for dimensional stability, wear resistance, and fatigue resistance. Prioritize POM and PA. Fiber-modified PPS and LCP materials have linear expansion coefficients close to metals, meeting the long-term use requirements of high-precision parts.
Transparent Structures: These structures require amorphous materials with good light transmittance. PMMA, PC, and transparent PS are preferred, while crystalline, opaque materials like PE and PP should be avoided to ensure optical transparency.
Complex Curved/Irregular Structures: These structures require materials with balanced toughness and molding compatibility. ABS and ABS+PC alloys are preferred, as these materials offer good impact resistance, easy demolding, and can accommodate the one-piece molding requirements of complex shapes.
