How does thermoplastic polyurethane differ from cast polyurethane?

TPU is processed like a thermoplastic, meaning it melts and is shaped by extrusion or injection molding, and it can be remelted repeatedly. Cast polyurethane cures chemically inside a mold using open casting technology and does not melt back. For thick, load-bearing parts made to size, cast polyurethane is the choice; for films, hoses, and cable, TPU is preferred.

Which polyurethane should you choose for a wear-resistant industrial part?

For liners, rollers, bushings, and scrapers that work against abrasion and impact, cast polyurethane is more practical: it is poured in a thick layer to a drawing and delivers abrasion loss of 38-39 mm³ per DIN 53516. TPU is stronger where thin flexible profiles, film, or cable insulation are needed in mass batches.

Can you order thermoplastic polyurethane products from TIMOL?

The TIMOL factory specializes in cast polyurethane using open casting technology, so it manufactures parts by exactly this method. If you were considering TPU for a wear-resistant assembly, the engineers will advise whether the task can be covered by a cast part and will calculate it to your drawing.

TPU and cast polyurethane look the same, so what is the catch?

Finished products really do look similar, but their behavior under load differs because of their different structure and manufacturing method. Cast polyurethane holds the dimensions of a thick part better and withstands higher specific loads, so you should not select the material by the appearance of the part alone.

What temperature range does polyurethane work in?

TIMOL cast polyurethane works from -60 to +100 °C, retaining its elasticity in the cold. This is the working range for most industrial assemblies. For prolonged contact with steam and hot water above +100 °C, the material and formulation must be agreed separately.

Thermoplastic Polyurethane (TPU): Properties and Differences

Engineers often confuse two different materials under the single name polyurethane and then wonder why the part they bought behaved differently than expected. Thermoplastic polyurethane TPU and cast polyurethane are materials that differ in structure and manufacturing method, even though the finished products made from them look almost identical. Let us break down what TPU is, where its strengths lie, and why the TIMOL factory casts precisely cast polyurethane for load-bearing wear-resistant parts.

What thermoplastic polyurethane is

Thermoplastic polyurethane is an elastomer that behaves like a thermoplastic: under heat it melts, takes shape through extrusion or injection molding, and solidifies after cooling. The main practical difference is that TPU can be remelted repeatedly, so scrap and rejects go back into processing. By chemical base, TPU comes as either polyether or polyester types: polyether grades offer better resistance to hydrolysis and low temperatures, while polyester grades add tensile strength and fast shape recovery.

This ability to tune properties at the synthesis stage is what makes polyurethanes so flexible in application. TPU combines the elasticity of rubber with the hardness of plastic, resists oils and abrasion, and holds its shape under deformation. It is precisely because of its recyclability and the option of fine profiling that it is convenient to process in mass volumes.

Where TPU is used

Thermoplastic polyurethane is ideal where thin flexible profiles and large batches are required. Classic applications are cable and wire insulation, high-pressure hoses, films and membranes, shoe soles, protective covers and pads. In these tasks, what is valued is precisely the ability of TPU to be formed by extrusion into a thin, stable profile and to be reprocessed.

However, in thick-walled load-bearing parts of industrial equipment the situation is different. Hopper liners, elevator buckets, rollers, bushings, scrapers, and seals work in a thick layer under high specific load and impact. Here what matters is not recyclability but the behavior of a massive part under load, and that task is better covered by cast polyurethane.

Cast polyurethane versus rigid plastics: the numbers

To understand why cast polyurethane is chosen for wear, it helps to compare it with the rigid structural plastics it is often set against. Cast polyurethane combines low abrasion loss with elasticity, whereas caprolon and ultra-high-molecular-weight polyethylene win on rigidity but have almost no elastic rebound.

Property	Cast polyurethane (PU)	Caprolon (PA6)	UHMW-PE
Abrasion, DIN 53516	38-39 mm³	30-90 mm³	15-30 mm³
Working temperature	-60 to +100 °C	-40 to +100 °C	-200 to +80 °C
Tensile strength	39-87 MPa	60-85 MPa	17-45 MPa
Hardness, Shore scale	50 Shore A to 70 Shore D	75-85 Shore D	60-70 Shore D
Rebound elasticity	34-61 %	5-15 %	5-10 %

The key difference is visible in the last row: the rebound elasticity of polyurethane is 34-61 % versus 5-15 % for caprolon. This means polyurethane dampens impact and returns to shape, while rigid plastic transmits the impact to the structure and can crack brittlely. In abrasion, polyurethane and UHMW-PE are close, but polyurethane is elastic at the same time, so it wins in assemblies where abrasion and impact occur together.

Engineer’s tip: select the material by the nature of the load, not by the name. If an assembly bears impact and vibration, elasticity is needed, and then cast polyurethane in the 80-95 Shore A zone works better than any rigid plastic. But if all you need is a rigid low-friction sliding guide without impacts, then caprolon or polyethylene is more appropriate. Do not automatically carry a grade from one assembly over to another.

Why TIMOL casts rather than extrudes

Open casting technology makes it possible to cast a part of any thickness and shape to the customer’s drawing or sample without an expensive mold. Liquid polyurethane is poured into a form, it cures chemically, after which the part undergoes machining to its final size. This approach is economical both for single parts and for small runs, something TPU extrusion, designed for mass thin profile, cannot provide.

That is exactly why the factory chooses cast polyurethane rather than thermoplastic for wear-resistant industrial products. Typical items are gathered in the catalog, and more detail about the material itself and its properties can be read on the page about polyurethane.

How to choose and order

The choice between thermoplastic and cast polyurethane comes down to the type of part. A thin flexible profile, film, or cable is TPU territory. A thick loaded part for abrasion and impact is cast polyurethane. If you are not sure which class your task belongs to, it is easier to describe the working conditions of the assembly, and a process engineer will advise on the material.

Practical conclusion

Thermoplastic and cast polyurethane are not synonyms but two materials for different tasks: TPU for thin profiles and mass batches, cast for load-bearing wear-resistant parts made to size. Describe your assembly and send a drawing or sample to the TIMOL factory through contacts, and the engineers will select the material and hardness and calculate the manufacture. The list of services is available in the services section.