With a bit of processing, common materials can be made into high-performance building materials, such as pollution-eating roofing and concrete.
In some applications, fiberglass insulation, foam insulation, and wood can be replaced by manufactured alternatives that are made from waste materials and select raw materials.
Cellulose offers huge potential for building materials. When processed, cellulose can be made into materials that replace wood, plastic, and brick. It’s already used as insulation, sourced from recycled newspapers.
Cellulose is an organic polymer that gives green plants their structural integrity. Wood is 40 to 50 per cent cellulose, dried hemp is about 45 per cent cellulose, and cotton fiber contains about 90 per cent cellulose. As a waste material found in waste paper, cardboard, and textiles, cellulose is abundant and can be used to create a material to replace wood and plastic.
Zeo, an Australian company based in New South Wales, has created a product called Zeoform that is composed of only cellulose and water. The company has patented the process, which uses cellulose from textile waste, recycled and reclaimed paper, industrial hemp, and waste and renewable plants. The process results in a material, the company says, that can be produced at varying densities and can be formed, moulded, or sprayed. The material does not contain glues or other chemical elements, but those can be added to achieve specific properties.
At low to medium density - 0.5 to 0.9 grams per cubic centimetre - Zeoform is applicable for products that require lightweight, thermal, insulating, and acoustical properties. High-density Zeoform (one to 1.5 grams per cubic centimetre) is made for applications such as building materials and automotive parts which require a high strength-to-weight ratio.
Higher-density Zeoform has some inherent water resistance, but the company says surface coatings would be appropriate for more intense weather conditions. Common oil-based and acrylic coatings, polyurethanes, resins, and so on will work with the product, which has binding properties similar to dense hardwood. High-density Zeoform is fire resistant, and has achieved a Bfs/s1 rating, according to BS EN 13501 standards.
As Zeoform can be sprayed, moulded, or formed, it can be used like wood or plastic. Applications include:
- Moulded components such as switches, handles, lighting, and musical instruments. Moulding tolerance is +/-1 millimetre, with CNC machining giving tolerances of +/- 0.1 millimetres
- Tubes and pipes for handrails, furniture legs, curtain rails, columns, and structural beams
- Flat-panel products such as doors, walls, ceilings, floors, shelves, cupboards, laminates, and counter tops.
So far, the company has used Zeoform to produce furniture, housewares, jewelry, industrial parts, musical instruments, and building cladding. According to Zeo vice president of global branding and marketing Zen Joseph, the company has not yet entered commercial production.
“We are seeking suitable industry partners to develop and commercialise Zeoform in the industry,” Joseph said.
Foam insulation such as XPS, EPS, and spray foam are commonly used building materials. They’re typically made from petroleum byproducts and use environmentally harmful blowing agents. In addition, their flame retardants, such as HCBD, are also environmentally harmful, though Dow Chemical now produces an alternative that the US Environmental Protection Agency says “is anticipated to be safer than HBCD.”
Malama Composites, based in San Diego, California, manufactures plant-based polyurethane foams for a variety of applications, including rigid insulation panels and pour foams for surfboards and molded decorative building elements. According to company chairman and CEO David Saltman, Malama would like to “pull our global economy into a carbohydrate-based sustainable industry.”
The company says its rigid foam product, AinaCore, competes on price and performance with ubiquitous products like Dow’s Styrofoam, while using nontoxic and plant-based components such as castor oil and soybean oil. Thanks to a polyol derived from recycled water bottles, the product achieves 18 per cent recycled content.
The company says AinaCore achieves an R7 insulation value and achieves a Class A fire rating without using toxic compounds such as triphenyl chlorinated phosphate (TCPP) or brominated diphenyl ether (PBDE), which have been banned in Europe and are on the EPA’s “Red List” of toxic substances.
Malama suggests the panels are well suited for use in structural insulated panels (SIPs), factory-built structures, and panelized housing systems. In the near future, the company would like to license its foam for use by manufacturers around the world.