Plastic Injection Molding 101: A Few General Faqs For Prospect Clients

23 September 2020
 Categories: , Blog


When in the manufacturing business, there is a big chance that you will eventually need some kind of plastic product. Plastic injection molding can make getting these parts easier. Here are a few things you may want to know. 

What are the most popular plastic injection molding materials?

Today, silicone is one of the most popular materials used for injection molding simply because there is such a high demand for silicone parts and products. However, a number of other plastic materials can be used for injection molding processes. Most types of plastic are in a fluid state when heated, which allows them to be injected into a mold for the proper formation of a final product. Two other types of plastic use include high-density polyethylene (HDPE), acrylonitrile butadiene styrene (ABS), polycarbonate (PC), and low-density polyurethane (LDPE).

Plastic formulations are chosen according to their attributes. For example, here is a look at common plastics, why they're valued, and what they are used to make: 

  • ABS - lightweight and flexible enough to be formed in a range of shapes (toys, kitchenware, auto parts)
  • HDPE and LDPE - high tensile strength and can be used to create especially thin products (plastic bags or containers)
  • PC - transparent and extremely strong; can sustain damage without fully breaking  (DVDs, cell phone screens, lenses for glasses) 

What is the basic process involved in injection molding?

Of course, all types of plastic injection molding can vary depending on the specific type of method used. However, you can get a good idea of the basic plastic injection molding process that goes something like this: 

  1. The plastic injection mold is custom created using the client's customized specifications 
  2. The materials to make the plastic parts are selected and carefully formulated 
  3. Heated plastics, at a perfect consistency, are injected into the closed molds 
  4. The molds and plastic are put through a cooling process to plasticize and harden the liquid materials 
  5. New plastic parts are removed from the molds 
  6. Parts are carefully trimmed of excess materials 

How many different types of injection molding are there?

Plastic injection molding is ever-evolving as computer technology grows as a big component in the industry and allows for more simplified molding processes. While this list is definitely not comprehensive and is always subject to change according to industry standards, a few of the common injection molding processes in use today include thin wall molding, gas-assisted injection molding, vacuum-force plastic molding, and silicone molding.