Custom Plastic Extrusion Terms – Part Three
In the first of the series we discussed extrusion industry terms you may hear during conversations and in printed materials related to extruders and tooling for the extrusion industry. In part two of our series, we tackled the top 10 thermoplastic extrusion terms relating to ancillary, or downstream equipment used to manufacture custom plastic profiles, tubing and other hollow profiles.
In part three of the series, we are going to address material terms you may hear extrusion suppliers talk about when they discuss plastic materials. Extrusion companies tend to specialize in a group of raw materials. Formtech specializes in the following thermoplastic materials.
ABS (Acrylonitrile Butadiene styrene)
Acrylic (Polymethyl Methacrylate)
ASA (Acrylonitrile Styrene Acrylate)
Butyrate (Cellulose Acetate Butyrate)
WPC (Wood Plastic Composites)
HDPE (High Density Polyethylene)
LDPE (Low Density Polyethylene)
LLDPE (Linear Low-Density Polyethylene)
MDPE (Medium Density Polyethylene)
Rigid PVC (Polyvinyl Chloride in a hardened form)
Flexible PVC (Polyvinyl Chloride with plasticizers)
TPR (Thermoplastic Rubber)
For more detailed information on these materials, please click here.
What we want to do in part three of the series is dive into some terms you will hear regarding extrusion materials. Here is our top 10 review:
Thermoplastic – Any material, such as Polyethylene, PVC and ABS, which can be re-melted and reprocessed without considerable loss of properties or scrap loss. In other words, the scrap materials, both post-industrial and post-consumer, can be recycled and reused into other useful products. This differs from thermoset materials, such as fiberglass, that set up permanently during the curing process. These thermoset materials cannot be ground and reprocessed. As a point of interest, Formtech is actually a net consumer of reprocessed materials, meaning we use more than what we make during the manufacturing process. With an eye on green manufacturing, we practice manufacturing techniques that reduce scrap, and we aggressively seek out products and industries that allow us to practice environmental stewardship.
Compound – Compound is the classic definition of a plastic material prepared for subsequent manufacturing processes, specifically in extrusion and molding. Compounding is a process of blending plastics resins with other additives, and melting the materials during a heating or melting process. This process changes the physical, thermal, electrical or aesthetic characteristics of the plastic. Compounds can be tailored to a specific application, and by using a wide range of additives and fillers specific performance parameters can be met.
Dry Blend – A dry blend is a free-flowing blend of compound, or resin, and other ingredients as prepared for extrusion. Dry blend materials are important for processors that have twin-screw extrusion equipment available that can utilize the powder materials without the additional step of compounding and making pellets. Formtech has a variety of twin screw extrusion lines in our Athens, Georgia manufacturing facility that utilize dry blend compounds. When you think about it, a compound has already been processed once to make a pellet. By using the powder form, or dry-blend, the pelletizing process has been eliminated, and more processing aids remain in the material. This is good for everyone!
Masterbatch – A masterbatch is a compounded resin or additive already optimally dispersed in concentration and is compatible with the main resin in the process flow. Typically, a masterbatch is used when some of the ingredients are used in such small quantities that make it very difficult to dispense them at the extruder. For instance, an ingredient may need to be added at 0.02% in a formulation. This type of additive will typically be blended by the manufacturer into a masterbatch that can be added at a higher percentage, typically something over one to three percent for better control and dispersion.
Color Concentrate – Not everything is black and white, and the plastics industry is a classic example of this. Take a look around wherever you are right now. You will likely see red, or blue, or green, or yellow, or a rainbow of other colors in use in plastics around you. Formtech employs a wide variety of color concentrates to make a rainbow of colors depending on the application. Do you need 1957 Chevy Primer match for your application. We can do that!
Pellets – Resins or mixtures of resins with compounding additives similar in shape or size that have been extruded or chopped into short segments to prepare them for molding operations.
Resin – Think of resin as the base ingredient in a plastic material formulation. These are the purest of plastic materials, but in most cases these resins cannot be extruded. Many other ingredients are then added to the base resin to enhance extrudability and performance of the plastic resin.
Polymer – Technically a polymer is a compound formed from two or more polymeric compounds through a process known as polymerization. In reality, many polymers are complex mixtures of resin, stabilizers, lubricants, processing aids and proprietary ingredients. The ingredients in a polymer will influence physical properties and performance of the polymer.
Processing Aid – An additive or component in a resin to facilitate processing. Some raw resins, like PVC, cannot be extruded without processing aids and other ingredients that help bind the material together during the melting and extrusion process. Processing aids can also improve surface aesthetics of the finished part by allowing the material to flow through the tooling.
Composite – By definition, a composite is a structural material consisting of a combination of materials. Typically, one of the materials is a strengthening agent, the other being a thermoplastic resin. Formtech manufactures a wide variety of composite products using wood fiber as the strengthening agent and PVC as the thermoplastic material. By utilizing these ingredients, we can increase stiffness and at the same time reduce thermal expansion and contraction. These physical properties are important in industries like construction, transportation, and a variety of other markets
We hope part three of our extrusion industry terminology review will help you better understand the extrusion process. Check back for the last part of our four-part series that will cover processing.
We are anxious to work with you and your team on your next plastic extrusion requirement. Give us a call at 614-531-9954 or email at email@example.com for more information or a quotation.