Nanotechnology in Homebuilding
Nanotechnology is having a significant impact on the homebuilding industry and has a vast range of applications to various other industries like communication, medicine, transportation, and agriculture. The science of nanotechnology calls for manipulating matter on a molecular scale atom by atom thereby developing new materials, devices, and structures. This holds promise to producing superior quality, highly durable, and more efficient products across many industries. The homebuilding industry is at the forefront of advances in nanotechnology.
There are materials and special coatings that have been developed through nanotechnology that make buildings and homes cleaner, safer, and stronger. These products in the future will allow these buildings and homes to operate with higher energy efficiency.
Nanoparticles of titanium dioxide are incorporated in materials and coatings to manage heat and light by blocking UV light from the sun. These same materials also have self-cleaning properties due to the photocatalytic effect. So in other words, the titanium oxide being used in paints, tiles, windows, and cement for its deodorizing properties also becomes increasingly hydrophilic or attractive to water. This is used to create windows that self-clean as the hydrophilic coatings can chemically break down absorbed dirt in sunlight. It also works as an anti-fogging agent on windows.
When the surface is smooth and not absorbent, nano particles combine with the surface, so liquids are repelled taking contaminants with them. With porous surfaces, the nano particles fill up the pores from the inside. Fungus, lichen, algae and moss (in and outside) can no longer adhere to the surface. Dirt and liquids can't get into the surface anymore and are simply repelled.
Nano-coatings are produced by combining elements at the molecular level to form a denser product. One end result is a coating that can be applied to a material to make it stronger and more-durable then in its original form. Reducing the molecular structure improves nearly all of the mechanical properties of the material including yield strength, tensile strength, fatigue strength, and elongation. One downside is that nano-coatings can experience decreased ductility relative to the original coating material. However, current research is focusing on developing nano-coatings that have high strength and durability, while retaining their ductility.
Nano-coatings were initially designed to be applied to steel and other conductive surfaces using electro-plating processes. But further developments have provided a variety of uses and designs for nano technology. Some coatings are made of self-assembling monolayers (SAM), which are thin, one molecule-thick layers spontaneously formed by a substance. SAM coatings have many applications, from scratch resistant coatings for glass to self-cleaning surfaces. Other coatings are applied as spray-on coatings or as powders that are added to composite materials to enhance the physical properties of the base material. Still other nano-coatings are used to increase the efficiency of solar panels by resisting composite and material build-up on the panel facing.
Nanotechnology can also be used to strengthen materials and improve upon qualities that in the past have hindered overall performance. Currently, companies have developed materials four times stronger than the strongest titanium alloys and these materials have the ability of resisting corrosion. Nano-materials contain only a few thousand or tens of thousands of atoms, rather than the millions or billions of atoms in particles of most conventional materials. Nanostructures can be obtained in a variety of materials including metallic, ceramic, semi-conductor, and diamond.
Insulation made from nanomaterials can create the highest thermal performance at minimal weight and thickness. Even air filters for air conditioning systems are being created using nanotechnology which are able to clean and filter air better than existing filters. The examples below explain different types of nano-materials, which could potentially be utilized to produce building products that are harder, stronger, and more durable.
|Nano-Silicon Carbide SiC
Nano-Ceramics are a type of nano-material with nanometer-sized particles embedded in a matrix that contains a large volume of material at the component interface due to the small particle size (some fibers developed are smaller than a DNA molecule). It is generally recognized that the smaller diameter fibers are more effective in strengthening ceramics, metals, or plastics. The University of Delaware has a U.S. Army-funded Center for Composite Materials. One of their objectives is to develop nano-ceramics for high strain conditions.
Nano-Structure Metals and Metallic Glass - With this technology, the structure of metal or glass material is denser then traditional forms of the same material. Johns Hopkins University is working on high-strength nano-structure metals. Extensive research has also been conducted by DARPA's Structural Amorphous Metals (SAM) program (see www.darpa.gov/dso/thrust/matdev/sam/index.html) and the NanoSteel Co. (see www.nanosteelco.com) regarding the production and utilization of bulk and sheet-steel materials.
A range of possible properties for nano-structured metals exist, including a steel material with the hardness of alumina ceramics and the strength of carbon-based fibers. Other potential attributes could include higher strength-to-weight ratios than titanium alloys, superior corrosion resistance over nickel-based alloys, and significantly increased weldability. One issue with nano-structure metals is that the higher strength and durability creates low-ductility. Johns Hopkins University is working on lower strain hardening technologies to help combat this characteristic.
Johns Hopkins University is also developing metallic glass composite materials for anti-armor applications. This would result in a material that is impact resistant and has extremely high strength. Possible applications include kitchen and bath fixtures, flooring, or advanced panel products.
The Next Frontier
Nanotechnology is the next frontier in the home building industry. With the use of nanomaterials, manufacturers will be able to integrate solar cells into roofing materials, make insulation more efficient, create self-cleaning windows, have stronger drywall, create easy to clean surfaces for bathrooms and kitchens, and make paint durable and mildew resistant. The US Business Weekly established nanotechnology, as one of the three key areas of work in the 21st century and the housing industry will be one of the leaders of innovation that will change the industry forever.