Monthly Archives: September 2021

What Role does Resin Selection Play in Structural Foam?

Anyone who works in the plastics industry understands how vital a role resin selection plays in injection molding, and how important it is to pick the correct resin for the correct product application. When it comes to structural foam molding, resin selection no different – choosing the right resin is critical for success. The base resin is the most important material component in the product development process, and performance will be dependent on the correct selection. Clear expectations and specifications need to be identified to be able to select the correct resin.

When creating a structural foam molded product, one of the top priorities should be identifying the type of resin being used. Understanding what the finished product is going to be used for is a good first step to take – several properties must be evaluated before choosing the right type of resin, including:

  • Chemical resistance – material that can resist most types of chemicals, such as acetones, ketones, oils, minerals, and acetates
  • Weather/environmental resistance – material that can withstand heat, corrosion, and oxidation
  • Temperature range – material that can withstand a wide range of varying temperatures
  • Flame Retardant—material that is burn resistant
  • Impact Strength – the ability of a plastic to absorb energy during plastic deformation
  • Flexibility – ability to bend and move without breaking

Since different resins offer different properties, knowing what application the plastic product will be used for is essential when choosing the right resin. With many resin classes to choose from, we have the opportunity to customize each product for every application.

What Types of Resin can be Used in Structural Foam Molding?

Once the resin has been selected, it needs to be capable of being molded using the structural foam molding process. This resin also must be compatible with other additives, such as colorants, elastomers, impact modifiers, and Chemical Foaming Agents (CBA).

Some high-quality resin materials to choose from for structural foam molded products include:

  • HDPE (High Density Polyethylene)—low-cost, weatherproof, and good chemical resistance
  • PP (Polypropylene)—good heat and chemical resistance
  • PS (Polystyrene)—strong and rigid
  • ABS (Acrylonitrile Butadiene Styrene)– good impact strength and rigidity
  • Polycarbonate – strong with good temperature range
  • PPO/PPE—excellent heat resistance and stability

The possibilities are endless when choosing a plastic resin for a particular structural foam molded component, but each resin should depend on what the structural foam molded part will be used for. The experts at DeKALB will help find the best type of resin for each structural foam molded component, no matter what the application.

The Structural Foam Process

Once the base resin and any additives have been selected, the molding process is ready to begin.  DeKALB focuses on low-pressure structural foam molding: during the molding process, the chosen resin mixes with a Chemical Blowing Agent (CBA) and/or nitrogen gas before being injected into the mold.  When injected, the combined material will create cells or bubbles on the inside of the molded part.  As the part cools, a solid resin layer forms against the mold, which will give it a solid exterior. The honeycomb structure of the molded part is rigid and strong, while at the same time making it lightweight and easier to move.

The DeKALB Difference

There are many benefits to utilizing structural foam molding to manufacture your components instead of other types of plastic injection molding. These benefits include:

  • Less energy waste – the structural foam molding process uses less energy per pound of plastic and uses less raw material overall
  • Increased performance – the structural nature of the resin in the component allows for better performance per pound.
  • Material variety – numerous types of resins can be used in structural foam molded products
  • Cost-efficiency – quality and easily-repeatable parts can be produced for less

DeKALB Molded Plastics is proud of the world-class quality reputation we have established in the structural foam molding industry. With a focus on continuous improvement, we achieve our high commitment to quality by adhering to clearly defined standards that help to control all process variables.

We have more than 40 years of experience serving our customers with high-quality structural foam molding services. With a wide range of capabilities in plastic processing and an experienced team of engineers, operators, and quality technicians, DeKALB Molded Plastics can handle any challenge.

Ready to see how DeKALB Molded Plastics can do for you? Click here to get your next project started.