Functional, REACH-Compliant, Ecologically and Economically Responsible Foaming of Polymer Products

Sustainability and the introduction of new properties (functionalization) are the main drivers to produce foam polymers. The incorporation of gas into the polymer matrix (1) strongly reduces the density resulting in material and energy savings and (2) creates new properties, such as thermal, acoustic and electric insulation, comfort and dimensional stability.

Provided that “microcellular gas cells” can be incorporated into the polymer matrix, the intrinsic mechanical and thermal properties of the basic polymers can be maintained and other properties, such as impact resistance and dimensional stability can even be improved, so that polymer foams may also be applied in structural applications.

To build up foam in a polymer matrix, one may use physical and/or chemical foaming agents or add syntactic microspheres/ granulates that will expand under the influence of temperature. However, several foaming agents and/or microspheres have some major ecological and/or economic drawbacks:
  • The chemical foaming agent ADCA (Azodicarbonamide) that is most often applied in polymer foams has been identified as a SVHC component (list of December 2012) for it can provoke respiratory problems. Recently, ECHA has included ADCA on the draft list for prioritisation.
  • The use of super critical CO2 as a physical foaming agent requires special machinery and a licence.
  • Microspheres or granulates filled with HC (hydrocarbon) contain inflammable gases limiting their application.

To give a competitive and ecologically valid answer to the increasing demand of foam polymer products (strong demand of insulation materials, lighter plastics, etc.), it is necessary to reconsider the foaming technology and the chemical agents that are being used. The economically sound substitution of SVHC foaming agents is an urgent challenge for the plastics processing, textile, coating and other industrial sectors. Substitution not only means a switch from one foaming agent supplied by one producer to another (in as far as they are available for the diverse polymers), but also means the related process and product developments and possible adaptations to the machinery.

Target Group
The research project addresses foam applications in textile and plastics processing sectors:
  • Producers of polymer products applying (or wishing to apply) physical and/or chemical foaming agents: plastics processing companies using extrusion and injection moulding; coating, laminating companies; producers of floor and wall coverings, of PUR or PS foam blocks, packaging products and composites.
  • Polymer producers and chemical companies with micro-encapsulation technology
  • Producers and suppliers of chemicals used polymer foaming (foaming, nucleating agents, foam stabilizers, etc.)
  • Compounders
  • Machine manufacturers and technology suppliers
The research project will perform the following tasks:
  • Screening and characterisation of foaming and nucleating agents that may be used in polymer foaming (thermosets, thermoplastics, composites, coatings)
  • In the case of textile coating: substitution of exothermic foaming agents by endothermic ones of combinations, for both plastisols (PVC) and dispersions (acrylate or polyurethane)
  • In the case of plastics: substitution of exothermic foaming agents by endothermic ones, evaluation of physical foaming, solid state pre-saturation, foam beads and micronized chemical foaming agents.
  • (Semi) industrial trials
  • Characterisation of the foam structures
Project Details
Project type: VIS
Approved on: 19/03/2015
Duration: 01/06/2015 – 31/05/2017
Total budget: €618.286
Subsidy: €494.630
Project Partners