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Your Guide to Plastic Resins

Your Guide to Plastic Resins

If you are looking for a plastic resin container, the following information will serve as a guide to help you in your selection. However, this information can only illustrate the many varieties of plastic resins that are available. Therefore, these descriptions are intended only as a manual to explain the options available, and you should not ignore compatibility testing to determine the container most appropriate for your purposes. All buyers are ultimately responsible to consider these descriptions and to examine their applications before deciding which containers, closures, and accessories best meet their needs.


Created with durable materials, PET and PETG containers demonstrate a gloss and clarity that make this resin perfect for use in food and beverage containers. This resin gives the look of glass, but because it is made of plastic, it features an increased resistance to strong impacts and breakage. Foods, beverages, personal care products, and pharmaceuticals are safer and more secure in a PET or PETG plastic resin container. In addition to these display and safety features, PET and PETG bottles and jugs are lightweight and convenient alternatives to more fragile glass containers.

Low Density Polyethylene (LDPE)

 Although very similar to HDPE containers, the LDPE composition is less rigid. This allows containers made from this resin to be even more flexible and therefore squeezable. Products such as shampoo, conditions, and adhesives are typically packaged in LDPE containers because they are so elastic. Because LDPE is less chemically resistant than HDPE, these containers are typically glossier in appearance. The glossier appearance makes them ideal for food and personal care products. 

High Density Polyethylene (HDPE) 

 Making it the most widely used resin in plastic bottles, HDPE is known for being both extremely durable and very economical. This plastic resin is naturally translucent in appearance, but that does not prevent it from being somewhat flexible and very resistant to impacts. Although HDPE cannot be used to contain solvents, it works very well with acid concentrates and some caustics. This application has made it a favorite for FDA-approved food grade products. Color can be added to the HDPE plastic to make it more opaque, but even with this addition, it will not become glossy. These containers can be used to hold substances at below-freezing temperatures, but anything heated to over 180 degrees Fahrenheit or anything requiring a hermetic seal cannot be enclosed in a HDPE container. 


Polypropylene (PP)  

 For products needing to be stored at high temperatures, PP containers are an excellent option. This plastic resin is exceptionally stable at high temperatures while providing a strong moisture barrier. Foods and beverages that are heated, such as pancake syrup, are well-contained in bottles and jars created from PP materials. This resin is also autoclavable, meaning that it can withstand the steam sterilization process created by high temperatures and heavy pressure. Because of these storage characteristics, PP preserves dried foods such as spices, dried fruit, and flour exceptionally well, trapping in the freshness and flavor. Although PP performs well in high temperatures and under strong pressures, it has very poor impact resistance, especially in cold temperatures. 


Polystyrene (PS)   

This plastic resin most closely mimics the appearance and strength of glass. With a strong, clear crystal appearance, PS also creates an oxygen barrier that serves to preserve the freshness of the products held inside. However, this resin does not respond well to changes in temperature or ultraviolet exposures. In addition, it has poor to moderate resistance to impact, much like the glass that it imitates.


Polyvinyl Chloride (PVC)  

Polyvinyl Chloride containers have a variety of uses due to their high resistance to oils and low oxygen transmission. With these attributes, this semi-rigid PVC resin is very resistant to chemicals. In addition, PVC provides a solid barrier to most gases, making it a strong selection for salad oil, mineral oil, and vinegar. Personal products such as shampoos and cosmetics are frequently contained in PVC as well. Although this resin is chemically resistant, it cannot contain solvents or be heated to more than 160 degrees Fahrenheit as these conditions can cause the resin to distort.