10 advantages of using plastic rather than metal

Peter Jacobs, senior director of marketing at CNC Masters, gives MPN the rundown of why medical device manufacturers should be ditching metals in favour of new plastic resins. 

The manufacturing of medical devices must involve using disposable materials to prevent the occurrence of infection. In addition, they are required to offer exceptional versatility and are economical at the same time. When they do, plastics can act as an excellent substitute for metals.

Plastics are disposable, malleable, durable, cost-effective and can outperform equipment made from steel, ceramic or glass. Here are some advantages of using this inexpensive and durable material in medical devices.

1. Flexible design language

Plastics are created using various resins. Although each plastic resin exhibits unique properties, all fabric plastic polymers render substantially greater flexibility relative to metals.

The manufacturing of medical devices involves complex designs, intricate geometry and textures making plastics a more practical choice.

Manufacturers typically employ computer numerical control (CNC) machining to manufacture medical devices with intricate structures and aesthetically appealing designs. As most shop owners operate at a small or medium scale, mini milling machines are considered ideal for achieving versatility, while occupying minimal space.

Latest techniques such as plastic injection moulding facilitate developing mould designs and parts with complex geometries, while rendering exceptional efficiency that rivals metals. Not only are plastics easily mouldable, but they also offer metal-like endurance and strength.

2. Convenient sterilisation

Surgical tools made of medical plastics are ideal for one-time use, as their disposal inhibits the spread of deadly infections. Modern technologies, however, have helped create special antimicrobial plastics employed in medical devices. Such special antimicrobial surfaces are effective at repelling and killing toxins despite the lack of regular sterilisation.

3. Enhanced Ergonomics

Plastic is lighter than metal, thus making medical instruments out of plastic keeps their weight to a minimum. This reduced weight enhances the comfort level of devices and tools for the medical practitioner and minimises fatigue during surgeries.

Plastic is also highly customisable, offering a significantly greater design capability relative to metals. The material is available in various colours, surface finishes, and textures, which boosts its user-friendliness.

Technological advancements in plastic composites have helped develop thermoplastic products that render on par performance with metals in domains such as strength-to-weight/stiffness. 

4. Safety

Medical plastic is shatter-proof and nonpermeable, which makes it an outstanding solution for safely moving biohazardous substances and curbing the spread of deadly pathogens. Medical plastic is also used to make tamper-proof caps to eliminate foul play in a patient's medical prescriptions.

5. Recyclability

Plastics are reusable, giving them a significant advantage compared with metals. Used plastics can be melted and reused several times, making them an economical choice for industry owners. Conversely, metal parts, once destroyed, must be discarded and swapped out with new ones.

Plastics can also be recycled and used to manufacture new components. This perk also contributes to curtailing the time taken to source new materials for manufacturing.

6. Economically efficient

Plastic resins are relatively affordable compared with metals, primarily because the production expenses of plastic parts are substantially cheaper than their metal counterparts.

Regardless of the volume of parts needed during a production cycle, plastics are more economical and offer equal benefits in the medical sector.

Moreover, plastics are more economical to store and ship than metals due to their lightweight and immunity to chemical attacks and corrosion. Modern-day plastics offer significant durability that alleviates their odds of being damaged during transportation, further preventing redundant expenses.

7. Aesthetic appeal

Injection moulding adheres to the prevailing aesthetics standards. These standards dictate that manufactured medical devices are aesthetically pleasing to replace the institutional appearance.

The injection process directly colours plastics and helps achieve natural transparency. This process makes identification simpler using colour-coding and increases the appeal of the products.

Plastic injection moulding creates final products that offer a distinctive array of functionality in the medical domain. The advantages of using injection-moulded medical devices comprise their compatibility, availability, aesthetic value and scaled-down costs. 

8. Greater life span

Although metals have longevity, they are prone to chemical and weather withering, thus curtailing their life span. In contrast, plastics are highly resistant to physical, chemical, weather and environmental attacks, and so provide greater resistance and a prolonged lifespan. 

9. Better compatibility

Plastic devices manufactured from injection moulding exhibit higher compatibility with imaging and X-ray machines than metals. They enable a sharper observation of bones due to the deeper penetration of the X-rays. Imaging results generated by plastic devices are more accurate than metals because they do not hamper the magnetism of MRI machines.

10. Environmental benefits 

Compared with metals, single-use plastic instruments are the preferred sustainable option. Companies have ascertained that the carbon footprint of single-use instruments is minimal and can help achieve net-zero relative to the average CO2 equivalent annual emission from a hospital that uses conventional metal instruments.

For instance, injection moulding, a part of the mass production process that manufactures plastic, leaves minimal scrap material behind, compared with metal creation. This process also requires a lower heating temperature than a metal, which uses less energy.

Final words

Plastic resins have been gaining momentum recently, owing to their exceptional properties such as being lightweight, durable, thermally conductive and economically efficient. 

With the advent of new polymers, plastics are swiftly replacing their metal counterparts in many industries, including medical science.