When rubber was in short supply during World War II, research chemist Otis Ray McIntyre was tasked with designing a flexible substitute material that had insulation properties.
In a Dow Chemical Co. lab in Midland, Mich., McIntyre did an experiment in which he combined styrene with isobutylene under pressure. When the pressure was released, the styrene formed a polymer and the isobutylene evaporated, making polystyrene foam.
The end result was a plastic containing tiny air bubbles that is solid but flexible, lightweight but durable (one cubic foot can float 55 pounds), and not only moisture resistant but unsinkable.
McIntyre’s discovery was made in 1941. Styrofoam found its earliest uses in floating devices, such as WWII buoys and the billets under six-man rafts for the U.S. Navy and U.S. Coast Guard. The foam blocks replaced empty metal drums that could be sunk if punctured by a bullet.
“What the military needed was a product that could float and be shot into but wouldn’t absorb water and go down,” Dow research scientist Brian Lieburn said. “That was the original application.”
Over the next 20 years, Styrofoam was introduced to the building and construction industry, where its thermal performance, moisture control and compressive strength made it a mainstay in the marketplace and one of the most recognizable brand names ever.
“We’re pretty proud of the tradition considering it went from a laboratory-invented polymer to something that is a widely used material and common in every day homes,” said Linda Jeng, a chemical engineer at Dow.
Nowadays, scientists like Jeng and Lieburn, who work for Dow Building Solutions, are showing how Styrofoam can help push the envelope of energy-efficient housing. That’s also an important feature for affordable housing, which 34 years ago prompted Dow to become a product and volunteer supporter for the non-profit housing group Habitat for Humanity.
When Dow’s brand of extruded polystyrene (XPS) foam is used on the exterior of above-grade walls, it offers a solid layer of protection that, unlike cavity insulation, covers all the studs and reduces thermal bridges. This, in turn, keeps the conditioned air — be it heated or cooled — inside the dwelling and the summer heat or winter chill outside.
Below grade, Styrofoam reduces heat loss through concrete walls, keeps basements and crawl spaces dry, protects against frost, and improves the energy efficiency of new and older homes.
The rigid blue board helps builders meet energy codes while lowering gas and electric bills for buyers.
Dow has been the national insulation sponsor of Habitat for Humanity since 1993, donating Styrofoam products to more than 2,500 builds in 2015 alone as well as some of its spray products.
“The segment of the population who will be most sensitive to the operating costs of the home are the people who are taking advantage of what Habitat offers,” Jeng said. “Because of the higher performance, they will pay less of their disposable income on utilities and can truly enjoy the savings while keeping the home operating in a comfortable environment both winter and summer.”
For 2016, Dow has pledged $1.4 million as well as donations of Styrofoam, sealants and house wraps for 43 Habitat builds around the world, including first-time projects in Bangladesh, Romania and the Ivory Coast.
“Because of Dow’s generosity, we are able to work toward our vision of a world where everyone has a decent place to live,” Jonathan Reckford, CEO of Habitat for Humanity International, said in a news release.
Brand confusion
Styrofoam hit another milestone last year when UL Environment validated that the insulation contains 20 percent pre-consumer recycled content on average, which will help Dow meet its 2025 sustainability goals. Dow says almost 100 percent of its scrap XPS is recycled into other Dow products.
The company’s list of Styrofoam products includes a variety of insulation boards, exterior wall sheathings, re-siding boards, buoyancy billets for floating structures, and the foam bases for holding flower stems in floral arrangements.
However, the popular brand often gets mixed up with the controversial expanded polystyrene products used for restaurant carry-out food that some in New York tried to prohibit as unrecyclable until a court overturned the ban.
“The down side of having a product that has 75 years of history is that people often misuse the word Styrofoam for products that aren’t truly our material,” Jeng said. “The disposable food containers are made from polystyrene foam but it’s not the Styrofoam product. The Styrofoam brand is associated with durable goods, not disposable goods. We’re intended to be insulation material that lasts for the life of the building. You don’t want to change it because the performance is guaranteed. As long as that home is standing the product is there to provide thermal insulation performance.”
Over the 50-year assumed lifetime of a building, the energy Styrofoam saves is more than 30 times the energy it takes to make it, Jeng added.
Next 75 years
Dow is converting all of its Styrofoam plants to polymeric flame retardant (PolyFR) technology, which replaces a flame retardant substance classified as a persistent bio-accumulative toxin with one that has low toxicity.
Dow says its PolyFR technology will probably set a new industry standard for both XPS and EPS foam insulation applications. So far, Dow’s XPS plants in Japan and Europe have converted with Canada to follow ahead of 2017 regulations there. The phased approach meets regional requirements while ensuring product availability.
Styrofoam products are part of Dow’s Infrastructure Solutions segment, which consists of building and construction, coating materials, energy and water solutions, and performance monomers. Last year the segment brought in $7.4 billion of Dow’s $48.8 billion of net sales. Infrastructure Solutions is expected to “grow modestly” in 2016, due in part to higher demand from recovering construction end markets, according to the outlook in the 2015 annual report.
“New possibilities for resilient, energy efficient and well-designed homes and buildings are being realized in neighborhoods and communities around the world thanks to imagination, science and engineering,” Tim Lacey, global business director for Dow Building Solutions, said in a news release.
“We are proud to offer 75 years of product innovation that addresses the need for long-term value as a sustainable building solution and look forward to improving, innovating and perfecting building envelope science well into the future,” he added.
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