Think tank: New US EPA rules on blowing agents for polyurethanes provide opportunities

01 September 2016 22:11 Source:ICIS Chemical Business

Dow Chemical is treating new regulations about blowing agents as an opportunity to grow the company’s business, as it seeks to incorporate the new generation of agents into polyurethane systems.

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 New blowing agents will provide unique characteristics to polyurethanes

Blowing agents are one of the key components for polyurethane systems. They create the cells that are responsible for the impressive insulating properties.

However, the first two generations, which include chlorofluorocarbons (CFC) and hydrochlorofluorocarbons (HCFC), damaged the ozone layer.

The third generation, which include hydrofluorocarbons (HFC), are ozone friendly, but they are also powerful greenhouse gases. If carbon dioxide (CO2) is given a climate-change score of one, some blowing agents would have scores of 800-1,300.

The US Environmental Protection Agency (EPA) has come up with a list of alternatives to HFCs under its SNAP (Significant New Alternatives Policy) programme. These alternatives represent the fourth generation of blowing agents, called hydrofluoroolefins (HFOs).

Replacing blowing agents is not easy because new materials can alter the performance of the polyurethane system. These systems contain several other components in addition to blowing agents, such as isocyanates, polyols, surfactants and additives.

Dow Polyurethane is one of the major formulators. It combines these various components into systems, which it then sells to customers. Depending on the system, the end result could be a layer of rigid-foam insulation, a flexible-foam mattress or a moulded piece of polyurethane.

For years, Dow and other formulators have studied how the previous generation of blowing agents interacted with the other components of a polyurethane system, said Chris Chrisafides, North America commercial vice president for Dow Polyurethanes. “If you want better energy efficiency or better density or better demould time for the system, we know which levers to push.”

But once one component is changed, it can affect the attributes of the resulting system, sometimes to the detriment of a particular characteristic.

For Dow, this is where the opportunity lies. Dow is developing new formulations that can provide customers with the comparable attributes while using the latest generation of blowing agents.

“It gives us a target for innovation at the end of the day,” Chrisafides said. “We think this is a great time for the polyurethanes industry. We view this as a positive step.”

By Al Greenwood