Molding Materials
Choosing the right plastic material is a critical step in any custom injection molding project. The performance, durability, and appearance of your final part depend heavily on this decision.
Before selecting a material, consider key factors such as:
1. Part function and application
2. Required strength, flexibility, and impact resistance
3. Environmental exposure (e.g., UV, heat, chemicals)
4. Aesthetic requirements (color, surface finish)
5. Regulatory or industry standards (e.g., food-grade, medical, flame retardant)
Different plastics exhibit unique behaviors during molding and in end-use conditions. One often-overlooked factor is material shrinkage. Each resin shrinks at a different rate as it cools, which directly affects dimensional accuracy.
Important: If you change materials between production runs-even with the same mold-part dimensions may vary due to differences in shrink rates. This can impact fit, function, and assembly.
To help guide your selection, below is a table of the most commonly used thermoplastics in injection molding, along with their key properties and typical applications.
Injection Molding Materials at RCH Plastic
We work with a wide range of thermoplastic materials to meet diverse application requirements across industries. ABS (Acrylonitrile Butadiene Styrene) offers excellent impact resistance and surface finish - ideal for automotive interior parts and consumer electronics housings. Polypropylene (PP) provides good chemical resistance and fatigue strength at a cost-effective price point, commonly used for living hinges, packaging, and medical components.
Polycarbonate (PC) delivers exceptional clarity and impact strength, making it the material of choice for LED lenses, safety equipment, and transparent enclosures. Nylon (PA6/PA66) combines high mechanical strength with excellent wear resistance, suitable for gears, bearings, and structural components. POM (Acetal/Delrin) is prized for its low friction and dimensional stability in precision mechanical parts.
Our engineering team provides material recommendations based on your part’s functional requirements, operating environment, and budget. We also offer glass-filled, UV-stabilized, and flame-retardant material grades to meet specific performance standards. Explore our injection plastic parts capabilities or request a consultation to select the optimal material for your project.
Need help selecting the right material? Our engineering team provides expert guidance based on your application requirements. Explore our plastic mold capabilities or learn about our DFM process for material optimization.