Green Chemistry Challenge: 2020 Designing Greener Chemicals Award
Johns Manville, a Berkshire Hathaway Company
Biobased Formaldehyde-Free Thermoset Binder Formulation
Johns Manville is being recognized for developing a biobased, formaldehyde-free thermoset binder for fiberglass reinforcement applications. Thermoset binders are used to bind glass fibers of fiberglass mats used in carpet tile backing. This technology eliminates the use of hazardous chemicals, reduces water and energy use, and produces a product with a longer shelf life.
Summary of Technology:
Thermoset binders for fiberglass reinforcement are mainly used in the carpet industry for binding glass fibers of fiberglass mats. Current binders can be formaldehyde-based or polyacrylic acid-based and may use phosphorus-containing catalysts. Formaldehyde is considered a probable carcinogen, and acrylic acid is a strong irritant; phosphorus can be harmful to aquatic ecosystems. Both systems can release hazardous chemicals over their life cycle, exposing building occupants to these chemicals.
Johns Manville has developed a formaldehyde-free biobased binder formulation for carpet mats that uses approximately 90 percent biobased content and is completely formaldehyde free. The binder uses renewable carbohydrates such as dextrose, which is nontoxic and non-hazardous and is produced from corn, potato, or wheat starch. The binder is produced using a phosphorus-free biodegradable acid catalyst at temperatures about 40oC lower than conventional acrylic binders. The dextrose-based binder provides a much improved shelf life of about 12 months, compared to less than one month for traditional binders, reducing the possibility of waste generation when unused product expires. The novel binder also uses less water and requires less energy for the evaporation of water.
The company’s data indicate that mats made with the novel binder have improved stability to heat and humidity and have better delamination strength than standard controls, adding a performance advantage to the product’s improved safety and environmental characteristics. While the commercialized version of the new binder is 91 percent biobased, Johns Manville believes 100 percent biobased binders are possible. The company also estimates the new product will reduce water usage by as much as 17,000 gallons per day and reduce energy usage by the equivalent of 138,000 cubic feet of natural gas per day at its plants.