By characterizing and then modifying molecular structures chemical engineers are able to
- Enhance desirable physical properties and performance attributes, and
- Suppress unwanted ones.
With each new development a greater understanding of the complex relationships between specific modifications and the changes they bring about is achieved.
While enormous advances have been made in recent years, there are still many challenges remaining.
The field of nanotechnology—one of the newer areas of materials science—makes use of the functional advantages that many materials demonstrate when they are produced in extremely small particle sizes. The prefix nano itself refers to a billionth (10-9), and in nanotechnology the basic unit of measurement is a nanometer, which is one-billionth of one meter.
A growing number of nanoscale materials and nanotechnology-related manufacturing techniques are already being used to
- Produce advanced composite materials that have such improved properties as electroconductivity, catalytic activity, hardness, scratch resistance, and self-cleaning capabilities;
- Produce consumer products, such as cosmetics and sunscreens, that have improved aesthetic appeal and effectiveness;
- Improve the performance of compact, ultra-sensitive sensors and other analytical devices used for detecting disease, monitoring food quality, and assessing environmental, radiological, biological, and nuclear hazards; and
- Enable such medical advances as nanoscale drug-delivery particles that allow for the earlier diagnosis and improved treatment of cancer and other diseases.
Today specialized techniques developed by chemical engineers enable many common materials to be produced with individual particle dimensions measured in nanometers. Nanometer-sized particles demonstrate a broad range of more favorable physical properties compared with larger-sized particles. These properties include
- Improved chemical resistance,
- Improved hardness and abrasion resistance,
- Increased tensile strength and flexibility,
- Favorable melting points,
- Favorable magnetic properties,
- Increased thermal and electrical conductivity, and
- Favorable surface-chemistry effects that improve the ability of a powder to be dispersed in a liquid.
Chemical engineers are heavily involved in the ongoing discovery of nanoscaled materials that demonstrate desired properties. They are also instrumental in the development of the complex engineered systems required to produce these materials in commercial-scale quantities for use in real-world applications.