What you need to know about the Environment Protection Agency’s proposed Rule 20

Formulating for the Next Generation HFO Blowing Agents in Europe?
Learn how Air Products can help

HFC Blowing Agents are under pressure to be phased out

Next Generation HFO Blowing Agents
Formulating for Spray Foam Applications
Formulating for Commercial Refrigeration Applications
Formulating for Rigid & Flexible Lamination Applications

The 2014 amendment to the European Union’s F-gas regulation now targets to phase down consumption of HFCs from 2015 to 2030 in steps, based on 2014 sales:    

Market prohibition dates:

  • 2015 – Domestic refrigerators and freezers that contain Hydrofluorocarbons (HFCs) with global warming potential (GWP) of 150 or more.    

Refrigerators and freezers for commercial use (hermetically sealed equipment):     

  • 2020 – Units that contain HFCs with GWP of 2,500 or more.    
  • 2022 – Units that contain HFCs with GWP of 150 or more    
  • 2023 – Other foams (such as polyurethane spray foam).


Therefore, under the new F-gas Regulation, the European Union is targeting to reduce emissions from HFCs by two-thirds by 2030.

In Spain, a taxation system on HFC-containing formulations was introduced in 2014; HFCs used in the production of polyurethane spray foam systems are now taxed at a rate of 10%, thereby presenting an incentive for formulators to investigate alternative blowing agents that are exempt from the tax.    

France, Poland and Sweden are each considering the implementation of a similar form of HFC tax.    

In the UK, BRE has introduced a voluntary green guide to specification, which provides guidance with regards to the use of building materials, such as insulation.   

Next Generation HFO Blowing Agents

In response to the F-gas Regulation, new alternative blowing agents with a low global warming potential (GWP) have been developed, namely HFO-1233zd(E) and HFO-1336mzz.

Offering notable environmental improvements, both of these new HFO blowing agents have a chemical structure that breaks down quickly, resulting in an atmospheric lifetime of weeks rather than years or decades. This class of chemical is a “fourth-generation” family of compounds, developed to replace a long line of similar substances that had high ozone depletion potential (ODP) or GWP.      

Air Products has been at the forefront of developing new catalysts and surfactants to enable the new blowing agent technologies     

Polycat® 203 and Polycat® 204 are non-emissive amine catalysts specially designed to deliver high-end results when used with both HFO-1233zd(E) and HFO-1336zz in 2K High Pressure Spray Foam Applications (SPF).    

Polycat 204 catalyst can help customers achieve between 6 to 8 months of polyol blend stability when used with HFO-1233zd(E).      

Polycat 203 catalyst performs similarly to Polycat 204 catalyst, but brings the added advantage of having a low water content, providing additional flexibility to formulators.

The table below compares reactivity drift of Polycat 204 catalyst versus conventional amine catalysts after heat aging at 50°C.

 Foam rate chart

Formulating with Polycat 203 catalyst / Polycat 204 catalyst in Spray Foam Applications

Typical uses levels of Polycat 203 catalyst / Polycat 204 catalyst are 2-4% by weight on the polyol side. The product can be used in conjunction with other catalysts to optimise system stability, overall reactivity as well as back-end cure speed.      

Recommended co-catalysts for HFO based systems include: Dabco® 2039 catalyst, Dabco® 2040 catalyst, Dabco® TMR-7 catalyst, Dabco® MB20 catalyst, Dabco® T120 catalyst and Polycat® 12 catalyst. Surfactant recommendations include Dabco® SI3503 surfactant, Dabco® SI4202 surfactant, Dabco® LK-221E surfactant and Dabco® LK-443E surfactant.

Below is a guide to using Polycat 203 catalyst / Polycat 204 catalyst with other Air Products Additives:

guide chart

Click here for a larger version

Formulating for Commercial Refrigeration Applications

Inherently, good flow ability is required to fill moulds when producing commercial refrigerators, in addition to good adhesion and thermal properties. Air Products has developed a range of additives for use in this application:     

Polycat® 210 gel catalyst is also stable in LBA based systems and can provide good adhesion between the foam and substrate.    

Dabco® TMR-7 post cure catalyst is again stable in LBA based systems, with excellent de-moulding properties and flow-ability.    

Dabco® SI3102 silicone surfactant is stable in LBA based systems, and can provide good surface quality and improved thermal properties.    

Formulating for Rigid & Flexible Lamination

Whilst in Europe pentane remains the dominant choice of blowing agent, there has been a growing interest in hybrid systems (Pentane & HFO). Air Products offers the broadest selection of amine catalysts, trimerisation catalysts & surfactants for lamination, including the following grades:    

Dabco® TMR-12 is our latest trimerisation catalyst and provides formulators with the necessary tool for tailoring isocyanurate foam reactivity. It facilities easier processing by virtually eliminating the ‘trimer kick’ that is usually seen with conventional trimerisation catalysts.   

Dabco® SI3504 is a capped surfactant, which has facilitated enhanced lambda and improved board aesthetics.   

Polycat® 5 remains the amine blowing catalyst of choice for PIR lamination systems.



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