January 14, 2014
What Paraffin Wax And LCD TVs Have In Common
[ Watch the Video: What Do LCD TVs And Candles Have In Common? ]
Lee Rannals for redOrbit.com - Your Universe Online
Researchers at the Physics and Material Science Research Unit of the University of Luxembourg made the connection between paraffin wax and liquid crystal while studying the crystallization process of wax on a macroscopic level.
Paraffin wax is produced as a by-product in the process of refining crude oil. The wax is widely used in candles, lubricants, paint, medicines and even beauty products to help get rid of ashy elbows or rough hands. Very little is known about the wax on a microscopic level, so the team decided to study paraffin at the individual molecular level and examine the process by which it crystallizes.
“We study crystallization in a model system for eicosane (C20) by means of molecular dynamics simulation and identify the microscopic mechanisms of homogeneous crystal nucleation and growth,” the researchers wrote in the paper entitled "Crystallization mechanism in melts of short n-alkane chains."
"For the nucleation process, we observe that chains first align and then straighten. Then the local density increases and finally the monomer units become ordered positionally."
The researchers found that wax molecules align in a similar way to molecules in liquid crystal before they move into their final positions, and which resembles the processes that take place in liquid crystal display (LCD) technology.
“The subsequent crystal growth process is characterized by a sliding-in motion of the chains. Chains preferably attach to the crystalline cluster with one end and then move along the stems of already crystallized chains towards their final position. This process is cooperative, i.e., neighboring chains tend to get attached in clusters rather than independently,” the researchers wrote.
Plastic products are created through the injection molding process in which molten plastic is injected into a mold and cooled to form a desired shape. The latest study gives insight into how to control any potential defects during this process.
“This research will be of value to the plastics industry as the polymers which make up plastics are really just long-chain versions of the molecules in wax,” said Professor Tanja Schilling, co author of the paper.