PU Engineering reactors for polyester polyols (PET/PA/AdAc) and resins

For more than 15 years the experts who created PU Engineering have developed cost effective solutions and innovative processes for the production of high quality polyester polyols and resins.

We do not only supply the hardware, we also supply the full know-how for efficient and quality production of polyester polyols and resins.

With the imposition of European Energy Efficiency Directive  and the development of chemical technique, currently the rigid PU systems mark a real consumer boom. The huge increase in the consumption of rigid polyurethane foams is the reason for the increased demand for raw materials for their production – the aromatic polyester polyols.

We are the only company that offers multifunctional reactors.

Each of our reactors is adapted for the production of:

  • aromatic polyesterpolyols based on PET and/or PA with different hydroxyl numbers, viscosity and chemical functionality
  • aliphatic polyester polyols based on adipic acid (AdAc) with different hydroxyl numbers, viscosity and chemical functionality
  • our reactors can be used both at atmospheric pressure and under vacuum.

PU Engineering reactors are completely automated and easy to operate. Recipe management allows to save different recipes, record the results and control each part of the equipment.

PU Engineering has in-house capabilities to upgrade and improve existing polyester manufacturing plants and process control systems.

Our industrial reactors for polyester production can be equipped with reaction IR spectrometers (FT-IR). This allows online monitoring of the hydroxyl number of the polyol and automatic interruption of the reaction upon reaching the set parameters.

Our polyester polyol reactors

Operating principle:

  • Discontinuous batch process.

  • Break down or recombined the materials through mixing, filling and cooling, to promote the reaction of polycondensation.


  • Body

  • gears

  • mixing devices

  • heating devices

  • cooling devices

  • valve and seals, etc.

Auxiliary Equipment:

  • Distillation column

  • head tank

  • condenser

  • water separator

  • collecting cans

  • filters

  • software operating system, etc.

Applicable Field:

  • All the liquid-liquid, liquid-powder reaction .


Our know-how for polyester polyols production

We specialize in delivering know-how according to our customer’s requirements. Based on the projects we have done so far, we can guarantee through our hardware the highly efficient production of the following types of polyesters.

Aromatic polyester polyols for rigid PU and PIR foams

OH- Number                      160 – 380                mgKOH/g

Acid Number                      1,0 – 2,0                  mgKOH/g

Dynamic viscosity             2500 – 6000           mPA*s


Aromatic Polyester Polyols with high aromatic content


OH- Number                      200 – 260                 mgKOH/g

Acid Number                      1,0 – 2,0                   mgKOH/g

Dynamic viscosity             5000 – 8000            mPA*s

Aliphatic polyester polyols

Aliphatic polyester polyols for thermoplastic polyurethane ( TPU ) application

OH- Number                      35 – 120                     mgKOH/g

Acid Number                      < 0,4                          mgKOH/g


Aliphatic polyester polyols for shoe soles


OH- Number                      55 – 120                      mgKOH/g

Acid Number                      < 0,4                           mgKOH/g

Aliphatic polyester polyols as additive for PIR/PUR foams

OH- Number                      200 – 260                     mgKOH/g

Acid Number                      1,0 – 2,0                       mgKOH/g

Dynamic viscosity             300 – 1600                  mPA*s

Targeted market for our polyester polyols

PU panel insolation




PU spray foam


TPU, coatings


  • Feasibility studies

  • Process control system software upgrades

  • Existing facility improvements

  • Turnkey plants