How to choose injection molding materials?

1, Understand the basic characteristics of injection molding materials
There are various types of injection molding materials, mainly including thermoplastic and thermosetting plastics. Thermoplastic materials such as polyethylene (PE), polypropylene (PP), polystyrene (PS), polyvinyl chloride (PVC), nylon (PA), polycarbonate (PC), etc. have the characteristics of repeatable heating softening and cooling hardening. Thermosetting plastics such as phenolic resins, epoxy resins, etc. form irreversible cross-linked structures after heating and curing, and cannot be reshaped.
When selecting injection molding materials, it is necessary to consider their physical properties (such as hardness, toughness, wear resistance), chemical properties (such as corrosion resistance, solvent resistance), thermal properties (such as melting point, hot deformation temperature), electrical properties (such as insulation, conductivity), and processing properties (such as fluidity, shrinkage rate).
2, Clarify application requirements
Product function: Determine the required performance based on the final use of the product. For example, automotive components may require high-strength and wear-resistant materials, while electronic product casings focus more on insulation and lightweight.
Environmental adaptability: Consider the product's usage environment, such as temperature, humidity, light, chemical exposure, etc., and choose materials that can adapt to these conditions.
Safety: Ensure that the selected materials comply with relevant safety standards, such as food contact materials that must meet food safety regulations such as FDA and EU.
Aesthetics: Consider the appearance requirements of the product, such as color, glossiness, transparency, etc., and choose suitable plastic materials.
3, Evaluate processing performance
Liquidity: The fluidity of materials directly affects the filling effect and product quality during injection molding. Materials with good fluidity are easy to fill the mold, but may lead to high shrinkage of the product.
Thermal stability: The stability of materials at high temperatures is crucial for the injection molding process, in order to avoid material decomposition that produces unpleasant odors or affects product performance.
Mold adaptability: Different materials have different degrees of wear on the mold, and suitable materials need to be selected according to the mold material and service life requirements.
Recyclability: Considering the recyclability of materials, for products with high environmental requirements, choose materials that are easy to recycle and reuse.
4, Cost benefit analysis
Raw material costs: The prices of different plastic materials vary greatly and need to be balanced based on budget and product value.
Processing cost: including energy consumption of injection molding machines, mold wear, production efficiency, etc. Choosing materials with good processing performance can reduce overall costs.
Maintenance cost: Consider the maintenance requirements of materials for injection molding machines and molds, such as whether special cleaning, maintenance, etc. are needed.
5, Environmental requirements
With the increasing global awareness of environmental protection, choosing environmentally friendly injection molding materials has become a trend. This includes biodegradable plastics, recyclable plastics, and materials with low VOC (volatile organic compound) emissions. At the same time, pay attention to the life cycle assessment (LCA) of materials to ensure that the impact on the environment is minimized throughout the entire process from raw material acquisition to product disposal.