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Plastic or synthetic material? Understand the differences and their importance

When delving into the world of injection molding, you'll frequently encounter two terms: plastic and synthetic material. Although often used interchangeably, there are subtle differences between these two materials. Understanding these differences is crucial for anyone looking for a partner in injection molding. In this article, we highlight the nuances between plastic and synthetic material and why these are important for injection molding projects.

Plastic vs. Synthetic Material: The Basics

To truly understand the nuances between plastic and synthetic material, it is essential to delve deeper into their definitions and properties. Both materials have their unique characteristics and applications in the world of injection molding and beyond.

Plastic: More Than a Collective Term

When people hear the word "plastic," they often think of commonly used disposable items, such as bottles, bags, and toys. But in reality, plastic is much more diverse than that:

  • Composition: Plastics are synthetic or semi-synthetic organic compounds. They are manufactured through polymerization, where small molecules (monomers) combine to form long chains (polymers).
  • Flexibility: Thanks to their chemical structure, plastics can be molded or shaped into various forms and sizes during production, making them extremely versatile for a variety of applications.
  • Types: Various types of plastics are available, such as polyethylene, polypropylene, and polyvinyl chloride, each with unique properties and applications.

    Different plastics are produced via different polymerization processes, resulting in polymeric structures with varied properties such as density, strength, and flexibility. For example, High-Density Polyethylene (HDPE) is known for its strength and is used for products like containers and pipes, while Low-Density Polyethylene (LDPE) is more flexible and is used for items like films and bags.

Synthetic Material: A Broader Spectrum

The term "synthetic material" has a broader definition than just plastic. Let's take a look at what it precisely means:

  • Definition: Synthetic material refers to any material that, at a certain stage of its production, can be molded by being liquefied and then solidified. This can be through heat and pressure, as well as chemical reactions.
  • Diversity: While all plastics are indeed synthetic materials (due to their ability to be molded), the category of synthetic materials also includes other materials, such as certain types of rubber or fibers, which technically are not considered plastics.
  • Functionality: Due to their moldability, synthetic materials can be used in a wide range of applications, from household items to industrial components and medical devices.

Pros and Cons

Considering the pros and cons of plastics and synthetic materials is essential in injection molding. Plastics are often cost-efficient, lightweight, and versatile but can pose environmental challenges such as the need for recycling and pollution risk. On the other hand, certain synthetic materials, like biocompatible polymers, might cost more but offer advantages like biodegradability and compatibility with medical applications.


Property Plastic  Synthetic Material
Cost Efficiency Generally cheaper, offering economic benefits Some, like biocompatible polymers, may be more expensive
Weight Lightweight, advantageous for many applications Weight varies depending on the type
Versatility Extremely versatile, can be molded in many shapes and sizes Versatile, but sometimes limited compared to plastics
Durability  Not always durable, can pose environmental challenges Some are biodegradable and more durable
Environmental Impact Risk of pollution and need for recycling Lesser environmental impact, depending on the type
Medical Applications Limited by biocompatibility Biocompatible polymers are suitable for medical applications

Why the Difference is Important for Injection Molding

Choosing the right material for an injection molding project is essential to achieve the desired results. Different applications require specific material properties. Understanding what each material offers enables better-informed decisions.

For example, in the medical industry, there's a growing demand for synthetic materials that can withstand sterilization processes without losing their integrity. This is an important point to consider if you're interested in cleanroom injection molding.

The Ecological Consideration

Environmental considerations are playing an increasingly significant role in the manufacturing industry. Therefore, understanding the difference between plastic and synthetic material is essential. Some synthetic materials, for instance, are biodegradable or can be recycled more easily than traditional plastics. This makes them an attractive option for companies wanting to reduce their ecological footprint.

If sustainability is a priority for your project, it's worth learning more about synthetic material injection molding: the green revolution in production.


Differentiating between plastic and synthetic material is not just a matter of terminology. It's about choosing the right materials for your specific injection molding project, considering both technical and ecological factors.

Whether you're an experienced professional in the injection molding world or just beginning to explore the possibilities, it's essential to understand how materials like plastic and synthetic material behave and what they can offer.