High Density Polyethylene (HDPE):
Most Commonly used for extrusion blown bottles. In its natural state HDPE is translucent and flexible, the addition of color will make it opaque. Adding extra weight will yield a more ridged package. Polyethylene is economical, impacts resistant, and provides a good moisture barrier. Compatible with a wide range of products that contain caustics and acids.

HDPE should not be used with products containing solvents. Additionally, due this resins tendency to crack at stress points we do not recommend its use in closures. Polyethylene is also available in Low Density and Medium Density (for a more flexible package), and High Gloss High Density

Polypropylene (PP):
Typically used for injection-molded closures and jars. Injection, extrusion, or stretch blow molding methods are employed to produce Polypropylene bottles. In its natural form Polypropylene is semi-clear to clarified and provides excellent contact clarity. PP also produces a high gloss finish when produced in colors.

Polypropylene provides a ridged package and its greatest strength is high temperature applications i.e. Hot Filling, autoclavable, and offers the ability to be steam sterilized. Polypropylene has excellent chemical resistance.

Subfreezing temperatures dramatically reduce this resins impact resistance. Oriented PP provides improved impact resistance and clarity at low temperatures.

Polystyrene (PS):
Commonly used for injection molded jars due to its clarity and stiffness at an economical price. This resin lends itself to most decoration methods without the need of flame treating. Polystyrene has a good oxygen barrier rating and a fair moisture barrier. Styrene is used to package dry goods such as spices and vitamins, it is also used for petroleum jellies and creams.

PS demonstrates a fair resistance to chemicals and acids. Its oil and grease resistance is rated as good. This polymer has poor impact resistance.

Styrene-Acrylonitril (SAN)
This styrene derivative offers the clarity and rigidity of Polystyrene in an engineering grade plastic. SAN has superior barrier properties, as well as improved chemical resistance when compared to PS. SAN is a fairly costly resin.

Acrylic Butadiene-Styrene (ABS):
A styrene derivative that offers greater impact resistance than PS. ABS is only available in solid colors.

Polyvinyl Chloride (PVC):
Typically used for blow molded bottles. PVC is extremely resistant to chemical and oils, and has a very low oxygen transmission. Provides an excellent barrier to gases. PVC is a clear (marked yellowing over time) drop impact resistant, semi-ridged material.

PVC is vulnerable to solvents and public relation difficulties. Many Environmental Scientist and Activists are of the opinion that chlorine atom expelled in the manufacture of this resin is a key factor in ozone depletion and global warming. None of Pearce Plastics' Products use this resin.

Polyethylene Terephthalate (PET):
Durable with an excellent gloss, clarity, and sparkle most commonly used for blow molded bottles. Oriented PET (OPET) offers a very good alcohol and essential oil and a generally good chemical resistance. PET is vulnerable to ketones and acetone attack. The orienting process improves gas and moisture barriers.

PET is not recommended for high temperature applications (160 degrees F maximum temperature). However, heat-set PET will accept high temperature applications to 195 degrees F. PET is typically used for Food & Beverage Products such as soda and juice, and cosmetics items that are high in alcohol like hair styling products.

Glycol Polyethylene Terephthalate (PETG):
Generally, used for shampoos, soaps, and detergents. PETG demonstrates a good impact strength and gas barrier. The chemical resistance of PETG is fair and product testing is highly recommended.

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