Solstice® Gas Blowing Agent

High performance, LGWP blowing agent for XPS and rigid polyurethane foam

Honeywell Solstice® Gas Blowing Agent has been developed for extruded polystyrene and pressurized one- and two-component polyurethane (PUR) foams. It is a replacement for HFC-134a, CO2, 152a, and other fluorocarbon and non-fluorocarbon foam blowing agents.

Solstice GBA is nonflammable by ASTM E-681 and EU A11 test methods. It has a very low global warming potential (GWP) of <1, a low Maximum Incremental Reactivity (MIR), Photochemical Ozone Creation Potential (POCP) and is VOC-exempt.

20-25% Better Long-Term Lambda than CO2-Blown XPS

Solstice Gas Blowing Agent allows extrusion of thick, dimensionally stable planks with lambda values of 27mW/m•K or lower (per EN 13164 Annex C) depending upon machine configuration and co-blowing agent used.


Solstice GBA demonstrates:

  • Good thermal and mechanical performance
  • Lambda: 20-25% improvement v. CO2 and similar to HCFC-142b and HFC-134a
  • Capability to extrude thick foam without capital investment
  • Capability to extrude low density foam
  • Compressive strength similar to HFC-134a
  • Dimensional stability similar to HFC-134a

Physical Properties

Molecular weight 114
Boiling Point -3°F (-19°C)
Vapor Thermal Conductivity 13.0 mW/m•K
Global Warming Potential (GWP) <1
Nonflammable ASTM E-681 and EU A11
Lambda 27 mW/m•K

Commercial Availability

Solstice Gas Blowing Agent requires minimal equipment changes and system optimization during transition from other foam blowing agents, thereby saving capital costs and lost production time.

Absolute cost effectiveness will depend on current energy efficiency standards and local regulations concerning the phaseout of high global warming potential materials.

Switching to Honeywell Solstice GBA now will streamline your transition and avoid an interim step – another opportunity to save capital.

Regulatory Status

European Union

  • Solstice GBA: Registered under REACH (article 24) to 1000+ tonnes


  • Registration complete

United States

  • Pre-Manufacture Notification (PMN): Complete
  • TSCA Inventory Listing
  • SNAP (Significant New Alternatives Policy) Application
  • VOC-exempt
  • U.S. EPA : Approved for rigid polyurethanes & extruded polystyrene

solstice gba-environmental properties-table