Chemicals covered in this application area

Increasingly, HFCs are being used as replacements for CFCs and HCFCs in foams and particularly in insulation applications. Compounds that are being used include HFC-245fa, HFC-365mfc, HFC-227ea, HFC-134a, and HFC-152a, as shown in Table 7.1. The processes and applications for which these various HFCs are being used are shown in Table 7.4 with predominantly open-celled foams being in shaded rows.

Table 7.4

Use of HFCs in the foam blowing industry (foam product emissions by gas - ODS replacements)

Cell Type

HFC Foam Blowing Agent Alternatives

Sub-application

HFC-134a

HFC-152a

HFC-245fa

HFC-365mfc (+ HFC-227ea)

O

PUa Flexible Foam

P

PU Flexible Moulded Foam

E

PU Integral Skin Foam

a

a

N

PU One Component Foam

a

a

PU Continuous Panel

a

a

a

PU Discontinuous Panel

a

a

a

PU Appliance Foam

a

a

a

C L

PU Injected Foam

a

a

a

PU Continuous Block

a

a

O

PU Discontinuous Block

a

a

S

PU Continuous Laminate

a

a

E D

PU Spray Foam

a

a

PU Pipe-in-Pipe

a

a

a

Extruded Polystyrene

a

a

Phenolic Block

a

a

Phenolic Laminate

a

a

a PU denotes polyurethane

The division of foams into open-cell or closed-cell relates to the way in which blowing agent is lost from the products. For open-cell foam, emissions of HFCs used as blowing agents are likely to occur during the manufacturing process and shortly thereafter. In closed-cell foam, only a minority of emissions occur during the manufacturing phase. Emissions therefore extend into the in-use phase, with often the majority of emission not occurring until end-of-life (de-commissioning losses). Accordingly, emissions from closed cell foams can occur over a period of 50 years or even longer from the date of manufacture.

Open-celled foams are used for applications such as household furniture cushioning, mattresses, automotive seating and for moulded products such as car steering wheels and office furniture. Closed-cell foams, on the other hand, are primarily used for insulating applications where the gaseous thermal conductivity of the chosen blowing agent (lower than air) is used to contribute to the insulating performance of the product throughout its lifetime.

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