Medical Blow Molding

Stretch (Tube) Blow Molding
Stretch blow molding utilizes a mold into which a polymer tube is inserted, heated and expanded under pressure to conform to the mold cavity. This process allows for a hollow, seamless, three-dimensional shape. Molds are generally economical due to the low-pressure process and limited complexity of design. Stretch blow molding is a primary process for producing high-pressure balloons.

Extrusion Blow Molding
Extrusion blow molding is a process where resin pellets are melted created a hollow tube-like structure called a parison. The parison is then pinched between two half-cavities of a mold, and air is blown into it. The air pressure expands the tube to conform to the shape of the mold (similar to bottle-blowing). Extrusion blow molding can produce a variety of geometries, balloons, vials, cuffs, bellows, etc.

Polyzen has the ability to understand the processing requirements to support customers fully in material selection, tooling design, development, and production.

Blow Molding Applications

Polyzen uses a variety of blow molding techniques to create a range of components and assemblies. These include:

Medical Balloons

Compliant, low-pressure, and non-compliant medical balloons can be produced cost effectively using blow molding technology. High-pressure balloons, such as those used for vascular catheter devices, can be produced using polyester, nylons, and polyurethane materials.


Semi-rigid and rigid thermoplastics, such a polypropylene, polyethylene, and polyvinyl chloride (PVC), are commonly blow molded for medical containers used for fluids, lab samples, or drugs. Similar technology is used to create structural and durable containers for biopharmaceutical, military, and industrial applications.


Blow molding can be used to produce polymer plastic vials in an endless assortment of sizes, shapes, colors, materials, and configurations. We’ve developed and manufactured medical vials for liquid storage, sample testing, and many other applications.

About Polyzen

Polyzen, Inc. is a leading contract developer and manufacturer of custom medical-grade polymer components and products for medical device manufacturers worldwide. With fully equipped facilities in Apex, NC, we’re capable of taking any customer’s concept from prototype to full-scale production. We offer a variety of technologies and turnkey services to meet the most demanding application and regulatory challenges.

Polyzen Can Help

Rely on Polyzen’s expertise to bring your medical polymer device needs to reality.

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