Within the plastics industry, compounding is the process of mixing and blending a base polymer with additives to manufacture a polymer blend that provides a specific set of properties. The compounding process is typically achieved via extrusion. The base polymer and the requisite additives are mixed and fed through an extruder. The screws of the extruder facilitate the melting and mixing of the polymer blend. The material, often now referred to as a compound or composite, exits the extruder via the die. The extrudate exits in long, individual strands that are often cooled using water baths or by spraying. After adequate cooling, these strands are cut into pellets and inspected as necessary for quality control. These pellets are then packaged and transported for further plastics processing such as injection molding.
Specialty compounding is a form of compounding that achieves a more customized and specific set of physical, thermal, electrical, and aesthetic characteristics in the final plastic product. While traditional compounding provides well-made products, manufacturers are turning to specialty compounding to ensure their products meet rigorous regulations and stand out from competitors. The possibilities are truly endless with specialty compounding!
It should be noted that specialty compounding is not a simple task and requires expertise as it demands precision as well as creativity. Amcor is a leader in specialty compounding solutions. Because we recognize that this process can be confusing, Amcor guides customers through each step of the specialty compounding process from product development through production including selection of the base resin, additives, fillers, and colorants to ensure the final product meets the customer’s unique and specific criteria.
Properties Enhanced by Specialty Compounding
The first step when creating a specialty compounded solution is identifying the best base resin for a given application. There are many base polymers to choose from and each provides its own set of pros and cons. At Amcor, there are a variety of base resins to select from including polypropylene, polyethylene, and polystyrene.
The next step is to determine which additives should be added to provide the requisite properties in the final plastic product. There are numerous properties that can be enhanced by specialty compounding and some of the most common are below.
- Color: does the final product need a specific or unique color in order to stand out? Colorants can be added to modify the color – and there are numerous colors to choose from to achieve the specific look you desire!
- Anti-static and conductivity: does the final product need to have anti-static properties? These additives are used to minimize the potential for static electricity build up on the surface of the plastic, and in some cases even prevent it entirely.
- Flame retardance: does the product need to prevent, delay, or slow down combustion? These additives are common in electrical products to avoid the ignition and burning of plastics.
- Anti-aging: nearly every plastic is prone to degradation when exposed to UV light, such as from sunlight, and oxygen including ozone. This degradation causes brittleness, discoloration, and loss of some physical properties. Additives, referred to as anti-oxidants, stabilizers, or anti-ozonants, are added to combat the deterioration of the plastic and to significantly extend the life span of the final product.
- Sterilization and anti-microbial: will the final product be used in the medical field, such as an implantable medical device? If so, there is a good chance it will require an additive to protect against deterioration of the plastic and reduce the potential for a microbiological attack.
- Odor: additive technologies have advanced significantly in recent years and manufacturers now have the option to alter the smell of the final plastic product! These additives modify the odor of the plastic to produce a more pleasing aroma.
- Other physical properties: there are literally hundreds of additives and each one modifies a specific property of the final polymer. Some physical properties that are often enhanced are impact resistance, stiffness, wear resistance, as well as resistance to heat, water, and chemicals.
Amcor: Your Specialty Compounding Partner
Our state-of-the-art compounding and blending processes ensure consistent master-batches and blended products each and every time. Our technical team takes a “hands-on” approach and is knowledgeable with resins, additives, manufacturing processes, and equipment. Whether you are foaming, molding, manufacturing film, extruding, or thermoforming, Amcor can be a valuable resource by your side.
Amcor is a manufacturer of polyethylene film and bags, as well as polyolefin compounds, additives, blends, and masterbatches. Amcor has grown from a single product line to hundreds of products and five product divisions. In addition to selling products, we also provide tech support, assistance with your equipment, and process recommendations. Amcor is also a full line distributor of various chemicals, resins, and gases for the plastic industry. With warehousing and distribution facilities across the United States, Mexico, Eastern Europe and China, we service companies of all sizes and locations across multiple industries.
Amcor realizes that quick turnaround, on time delivery, a quality product, and personal service are what it is all about. Contact us today to learn how we can assist with your next project!