Most copolyester elastomer purchases start from a spec that names another company's grade. The part was designed years ago, the drawing calls out the incumbent, and now the buyer needs a second source, a shorter lead time, or a replacement for a grade gone obsolete. This guide covers how a TPC-ET cross-reference actually gets made, and what to send to get a reliable one.
Looking for a Hytrel or Arnitel alternative?
Most buyers name the category by its best-known trade names: the spec calls for Hytrel, or Arnitel, or "equivalent." Sipolprene TPC-ET is that equivalent for most standard grades, and cross-references to commonly specified Hytrel and Arnitel grades are available on request. The goal of a cross-reference is a place on the approved vendor list next to the incumbent, qualified on your own tooling, so the program has a second source with its own supply chain behind it.
How a TPC-ET cross-reference works
A cross-reference is a match on the values that determine fit and function, confirmed by qualification on your own equipment. It is a starting point with engineering behind it. What follows is the checklist behind those matches, so you can see what a serious cross-reference accounts for.
The five values that determine a match
- Shore D hardness. The first sort. TPC-ET grades are named and specified by Shore D, and the match should land within a couple of points. Hardness also places the grade in its behavior family: elastomeric (Shore D 28 to 45, rubber-like, excellent fatigue and cold performance) or plastomeric (Shore D 46 to 72, engineering-plastic stiffness).
- Melt behavior for your process. An injection molding grade and an extrusion grade at the same hardness are different products. Extrusion needs high melt viscosity so the profile holds shape out of the die; molding needs flow. In the Sipolprene system, HV suffix grades carry the high viscosity for hose, belt, and film extrusion, achieved in the reactor without solid-state polymerization.
- Key mechanicals. Tensile strength, flexural modulus, elongation, and, for seals, compression set. These confirm the hardness match carries through to how the material behaves under load.
- The additive package. Suffixes on the incumbent grade encode stabilizers, and they must carry over. Sipolprene's system: W for UV stabilization, K for enhanced heat stability, L for reduced surface friction, B for black masterbatch coloring. An outdoor cable jacket cross-referenced without its UV package will match the datasheet and fail the service life.
- Compliance. Food contact, drinking water, RoHS, REACH. Selected Sipolprene grades carry food-contact and drinking-water clearance, and stating the requirement first keeps the match inside the cleared set.
Special cases worth knowing
Two parts of the Sipolprene range solve problems a plain hardness match does not cover. Fast-cycle injection molding grades crystallize faster for shorter cycle times in high-volume molding, worth evaluating when press time is the cost driver even if the incumbent is a standard grade. And Sipolprene 35150 is a PVC modifier engineered with a controlled 150°C melting point for compounding into PVC; we are not aware of a direct equivalent from another manufacturer, so it enters a formulation as a capability rather than a cross-reference.
Deciding between TPC-ET and TPU first?
If the spec is open and the question is which elastomer family the part belongs in, start with TPC-ET vs TPU: when a copolyester elastomer wins.
Request a SampleWhat to send
Four items get a cross-reference moving in one pass: the current grade name or its datasheet, the process, the service environment, and any compliance requirements. From that we propose a Sipolprene grade, supply the TDS, and send a sample for qualification. The qualification run on your own tooling is what turns the proposal into a second source; processing windows differ between manufacturers even at matching datasheet values, so plan one trial before committing production.
Frequently asked
Can Sipolprene replace the copolyester grade I run today?
Cross-references to commonly specified TPC-ET grades, including Hytrel and Arnitel, are available for most standard Sipolprene grades. A cross-reference is a qualified starting point, matched on hardness, melt behavior, and key mechanicals. The confirmation happens on your own tooling with a sample quantity.
What information do I send for a TPC-ET cross-reference?
The current grade name or its datasheet, the process, the part's service environment, and any compliance requirements. The datasheet covers most of it; the application context catches what the datasheet misses.
What do the suffixes on a copolyester grade mean?
They encode the additive package or a process variant, and they must carry over in a cross-reference. In the Sipolprene system: HV is high-viscosity extrusion, W is UV stabilization, K is enhanced heat stability, L is reduced surface friction, B is black coloring.
Are food-contact TPC-ET grades available?
Yes. Selected Sipolprene grades are cleared for food contact and drinking water, and the range is RoHS and REACH compliant. State the requirement at the start so the match is made inside the cleared grade set.
Send us the spec
Send the grade name or datasheet you are working from. We will propose a Sipolprene match, provide the TDS, and get a qualification sample moving.
View the Sipolprene range