Fluoropolymer Products: What is the difference between Injection Molded PFA and Machined PTFE parts?
Fluoropolymers offer a unique set of characteristics that allow products to perform even under the harshest of conditions. Both PFA and PTFE are material choices for fluoropolymer products, and both offer excellent options for critical applications. In general, both PFA and PTFE offer unmatched chemical compatibility, a wide temperature range, are very strong and durable and offer great non-stick properties.
PFA vs. PTFE – The differences between Fluoropolymer Materials
However, there are significant differences between using PFA and PTFE for your fluoropolymer parts. High purity PFA resin has lower trace metal content than PTFE, which may be invaluable depending on the end use of the product. PFA is translucent where PTFE is opaque. And perhaps the largest difference between PFA and PTFE fluoropolymers is the manufacturing process that is used.
Injection Molded PFA vs Machine PTFE Fluoropolymers
PTFE is a non-melt processable fluoropolymer which means that it must be machined to be formed into the necessary parts. While initially machining parts out of PTFE can be convenient and cost-effective for prototyping purposes or small part runs, once production quantities increase, the cost of machined PTFE fluoropolymers may become cost prohibitive. Additionally, the machining aspect of PTFE can also add significant metal contamination and can also be very time consuming.
PFA is a melt processable fluoropolymer which means that it can be heated until molten and then using injection molding or blow molding techniques can be formed into the necessary product shape. Injection molding is inherently a cleaner manufacturing process than machining and offers the ability to mold very intricate features and shapes with logos/markings included. Injection molding is more efficient and offers a quicker turnaround time. Additionally, once the initial tooling cost is absorbed, the cost per part is much lower than with machined PTFE fluoropolymers. Therefore, if high production quantities are expected with a new product or quantities are increasing with an existing product, using injection molded fluoropolymers will often be the most cost-effective business decision.
PFA is not the only fluoropolymer resin that is melt processable
While PFA is the gold standard for high purity and has many other beneficial features including a wide temperature range and excellent non-stick properties, it can be more expensive than other melt processable fluoropolymer resins. There are other resins available that may be less expensive but still achieve the product requirements needed. Other melt processable fluoropolymer resins that are available for injection molding include FED, PVDF, ETFE, and ECTFE. Our PFA material data sheet compares some of the primary features of all the fluoropolymer resins available.
There are many considerations to choosing the right materials and the right manufacturing process to meet all your unique product requirements. Please reach out to us to help you explore the different fluoropolymer options and to do a break-even analysis to show the cost benefits of switching to injection molded fluoropolymer products.