Super-engineering resins are some of the most valuable materials in modern plastics processing. Materials such as PEEK, PEKK, and ULTEM™ are used in demanding applications across aerospace, medical, electronics, automotive, telecommunications, and other high-performance markets because they offer exceptional strength, heat resistance, dimensional stability, and design flexibility. Asaclean’s high- and low-temperature changeover guidance notes that these resins were originally designed for aerospace and have become increasingly common in molding shops and extrusion plants.
But for all their advantages, super-engineering resins create one major processing challenge: they are extremely difficult and expensive to purge.
Once processing temperatures move above 700°F, changeovers become slower, contamination becomes more costly, and resin degradation can happen quickly if the machine is not managed properly. Asaclean notes that super-engineering resin changeovers tend to take much longer than typical engineering or commodity resin changeovers, and that scrap becomes much more expensive because of the high cost of the production resin.
That is where the right purging compound makes the difference.
For processors running PEEK, PEKK, ULTEM™, and other high-temperature materials, Asaclean® offers two high-performance purging compounds designed for these conditions: PX2 Grade and PF Grade. Both are engineered for processing temperatures from 280°C / 535°F up to 420°C / 790°F, making them strong options for demanding super-engineering resin applications.
Many processors have already tried a product marketed as a high-temperature purge. Unfortunately, that experience often creates skepticism.
A purge may technically be labeled “high temp,” but that does not mean it can effectively clean at the upper end of the temperature range where PEEK, PEKK, ULTEM™, and similar materials are processed. At these temperatures, a weak purge may fail to fully displace the resin, leave residue behind, degrade in the barrel, or create contamination that appears in the next production run.
That is why processors sometimes assume purging compounds do not work for super-engineering resins. In reality, the issue is often not the concept of purging. The issue is that the purge they tried was not engineered for the full demands of the application.
Asaclean PX2 and PF are designed for temperatures up to 420°C / 790°F and there are not other competitive products available that work effectively at the high end of this temperature range.
That distinction matters. When production materials are this expensive, and when downtime or contamination can quickly become costly, processors need more than a generic high-temp claim. They need a purge that is built for the temperature, resin behavior, and risk profile of the application.
Super-engineering resins are designed to perform in extreme environments. That same durability makes them difficult to remove from a screw and barrel.
When these resins are not fully removed, they can degrade, carbonize, or create layering inside the machine. This can lead to black specks, contamination, start-up scrap, and repeated processing issues. If the system is cooled before the resin is properly removed, the material can become extremely difficult to clean from the screw flights. Asaclean warns that lack of proper purging can result in resin degradation during subsequent runs and can make screw cleaning much more difficult if the machine is cooled before the resin is removed.
The cost of these problems is not theoretical. Super-engineering resins can be many times more expensive than standard engineering or commodity materials. A small amount of scrap can quickly turn into a major cost. A failed changeover can create hours of downtime. A screw pull can turn a manageable issue into a maintenance event.
At these temperatures, the purge needs two things:
First, it needs thermal stability. The purge must survive the processing window without breaking down.
Second, it needs cleaning power. It must remove high-performance resin from the screw, barrel, and flow path before that material degrades or contaminates the next run.
That is exactly where Asaclean® PX2 and PF are designed to perform.
Asaclean® PX2 Grade is designed for processors who need stronger cleaning performance at super-engineering resin temperatures. It is especially useful when the goal is to remove stubborn high-temperature resin from the screw and barrel and avoid costly contamination.
Asaclean describes PX2 as a specialized product designed to help remove super-engineering resins from the screw and barrel and avoid contamination. It also notes that when contamination occurs, PX2 can usually clean the machine effectively and help avoid the need for a screw pull.
That makes PX2 a strong fit for difficult high-temp situations, including:
PX2 is glass-filled, which gives it a stronger mechanical cleaning action. That deeper scrub can be valuable when the production material is difficult to displace or when the consequences of leftover residue are especially high.
For processors who have been disappointed by other high-temp purges, PX2 is often the product that changes their perception of what a purge can actually do.
Asaclean® PF Grade is a strong option for high-temperature color and material changeovers. It is designed for processors who need a thermally stable purge that can run at the same high temperatures as many super-engineering resins.
Asaclean PF Grade is an excellent choice for color and material changeovers at high temperatures. PF is safe for hot runners and effective for sealing machines before maintenance, weekend, and holiday shutdowns.
That makes PF especially useful for:
PX2 and PF are both designed for high-temperature applications, but they serve different needs.
Use PX2 when the priority is deeper cleaning.
PX2 is a stronger choice when you are dealing with stubborn residue, contamination, carbon, or a resin that is difficult to remove. It is a strong option when the goal is to clean the screw and barrel thoroughly and avoid a manual screw pull.
Use PF when the priority is general-purpose high-temp purging or sealing.
PF is a strong choice for high-temperature color and material changeovers, and hot runner applications.
In many plants, both grades have a role. PX2 can be used when the process requires more aggressive cleaning, while PF can be used as the go-to high-temp purge for changeovers, and hot runners.
When processors evaluate purging compounds, the price of the purge sometimes gets too much attention. That is understandable, but in super-engineering resin applications, the cost of not purging properly is usually much higher.
The real cost drivers are:
Asaclean reports that customers save 63% on average when purging super-engineering resins.
That number matters because the economics of super-engineering resin processing are unforgiving. If a purge helps avoid even one failed start-up, one extended changeover, or one screw pull, it can justify itself quickly.
One Asaclean customer quoted on the page described running a $25/lb material and seeing good parts in 15 minutes after using PX2, noting that a small amount of purge paid for itself in one cycle.
That is the kind of impact processors are looking for: not just a cleaner screw, but faster recovery, less scrap, and more sellable parts.
Some of the most difficult changeovers happen when a processor needs to move from a super-engineering resin to a lower-temperature material. For example, changing from PEEK to ABS introduces a major temperature gap. If the high-temp resin is not fully removed before temperatures are reduced, contamination and layering can occur. If the low-temp resin is introduced too early at high temperatures, it can degrade.
Asaclean’s guidance explains that a single purge is not enough for these high-to-low temperature transitions. Instead, the recommended approach is a two-step purge using specialty grades suited for the production scenario.
For a transition such as PEEK to ABS, Asaclean recommends first purging the PEEK with PX2 or PF while gradually lowering the temperature within the recommended range. Then, the processor can chase PX2 or PF with another Asaclean grade such as U Grade or EX Grade while continuing to lower temperatures toward the next production resin.
This approach helps processors avoid creating a layer of degraded high-temp resin in the barrel and reduces the risk of contaminating the next production run.
Processors running PEEK, PEKK, ULTEM™, and other super-engineering resins do not have much room for error. The materials are expensive. The processing windows are demanding. The temperatures are high. The cost of contamination is serious.
That is why Asaclean® PX2 and PF are not just “high-temp” purges. They are high-temperature purging solutions designed for the real-world challenges of super-engineering resin processing.
PX2 provides deeper cleaning power when stubborn residue, carbon, or screw/barrel contamination are the concern. PF provides high-temperature general-purpose purging, hot runner compatibility, and sealing performance for shutdowns and maintenance. Together, they give processors a stronger path to reduce scrap, avoid downtime, and run high-value materials with more confidence.
If you have tried a high-temp purge before and were disappointed, the problem may not be purging itself. The problem may be that the product was never built for the highest end of the temperature range.
Asaclean® PX2 and PF are different. And when you are processing materials like PEEK, PEKK, and ULTEM™, that difference can determine whether your next changeover is a costly problem or a controlled process.
Running PEEK, PEKK, ULTEM™, or another super-engineering resin?