Shape Seamless Plastic Devices with Thermoforming
Thermoplastics, such as polyvinyl chloride (PVC), polyethylene and polypropylene, currently make up more than 75 percent of the plastics in medical devices. Thermoforming is one of the most efficient and cost-effective ways to manufacture and prototype medical devices in today’s market. We break down how thermoforming has transformed the medical device industry.
What is Thermoforming?
When a polymer-based, plastic sheet is heated to a certain temperature, it becomes malleable. Therefore, thermoforming is the process of using a vacuum, pressure or mechanical assistance to shape the heated material into its product form. The method may involve one or two molds on either side of the apparatus that shape the component.
Why Thermoforming is a Method of Choice
The process allows for design versatility thanks to its commonly used materials and simple mechanisms. So, how exactly does thermoforming benefit healthcare?
Thermoforming uses lightweight, flexible materials that are designed to withstand medical applications. Unlike some metals, plastics can be easier to manipulate for production. In addition, these plastics often meet criteria for cleanliness and medical compatibility.
Some examples of this include:
- PET (polyethylene terephthalate) is easily recyclable, making it a good option for packaging, tubing, pans and other disposable components.
- Thermoplastic elastomers, or TPEs, are safe for human contact and do not have harmful phthalates or latex proteins. They are perfect for syringe tips, bags, tubing, and even masks.
- Several thermoplastics, including PPSU (polyphenylsulfone), are degradation resistant to radiation and heat-based sterilization.
- Thick-gauge or heavy-gauge (e.g. Thermoplastic PolyOlefin) plastics are durable. They make sturdy panels and covers for medical and diagnostic equipment.
The mechanics of thermoforming are straight-forward. The procedure consists of resin sheets that are carried into a heating chamber to reach their forming temperature. The machine then transfers the sheet to the mold where plugs and pneumatic equipment push the sheet into the mold’s gaps and fissures. Finally, the formed plastic is trimmed and excess plastic is reused.
This manufacturing method has several benefits:
- Simple prototypes for newer devices
- Quick overall turnaround
- Design flexibility and adaptability
- Capacity to create larger devices
- Less expensive assembly and engineering than injection molding
- High-quality products with detailed finishes
- Allows use of dyed or colored materials
Not all devices are appropriate for thermoform production, however. Complex products with multiple layers or types of materials often rely on other methods. Molds are limited to one side (or two sides sealed together), and some shapes may not be viable. Finally, premium plastic sheets can be expensive and ill-suited for high-volume production.
Creating Effective Products for the Medical Field
Vacuum forming, pressure forming and other methods of thermoforming account for many of today’s most useful devices in hospitals and home care.
- Lidded and non-lidded, disposable packaging
- Radiotherapy masks
- Dental castings and mouthguards
- Hospital room panels
- Fluid bags
- MRI equipment
- Medical trays
- Some prosthetics
The unique qualities of thermoplastics and thermoform design help successfully solve problems in the medical field. An example is the use of vacuum-formed plastics that currently help neurologically handicapped patients who are confined to a wheelchair. A custom-shaped seat insert evenly distributes the patient’s weight to prevent scoliosis and hip contractures. The production utilizes thermoplastics that effectively resist impact, heat, moisture and odor.
SealWerks can cater to the manufacturing and design needs of your particular device. Our prototyping services and production solutions help you develop the highest-quality product. Contact us to learn more about our medical industry services.