Author: Emil Venere of Purdue University
Publication Date: October 9, 2014
Link:http://www.purdue.edu/newsroom/releases/2014/Q4/electrically-conductive-plastics-promising-for-batteries,-solar-cells.html
Summary:
The race is on for finding alternative energy resources. Researchers at Purdue University have found a great alternative for solar cells. Scientists are studying a specific polymer called PTMA, a polymer with the ability to produce more than ten times the amount of electrical conductivity as commonly used semiconducting polymers. But what makes this polymer so special is that it is a radical polymer, an electrically conductive plastic that poses as a low-cost, easily manufacturable polymer that could possibly serve a purpose as lightweight, flexible batteries, antiglare coatings for cellphone displays, antistatic sheath to protect aircraft carriers from lightning strikes, flexible flash drives, and thermoelectric devices, which generate electricity from heat. It is a polymer that is similar to Plexiglas due to its inexpensiveness and ability to be used in a variety of products, but is able to conduct electricity. Polymers are composed of a central skeleton of monomers and depending on the polymer, contain side chains that are are attached to it known as “pendant groups”. Pendant groups in radical polymers are the main reason for electrical conductivity, because the pendant groups are able to let charge pass through, resulting in a current. The process of creating a radical polymer is known as deprotection, this process includes replacing a hydrogen atom in the pendant group with an oxygen atom. Electrons in an outer shell are usually paired with another, but in this polymer, the new oxygen atom is left without a pair and therefore, makes it capable of transporting electrical current.
The race is on for finding alternative energy resources. Researchers at Purdue University have found a great alternative for solar cells. Scientists are studying a specific polymer called PTMA, a polymer with the ability to produce more than ten times the amount of electrical conductivity as commonly used semiconducting polymers. But what makes this polymer so special is that it is a radical polymer, an electrically conductive plastic that poses as a low-cost, easily manufacturable polymer that could possibly serve a purpose as lightweight, flexible batteries, antiglare coatings for cellphone displays, antistatic sheath to protect aircraft carriers from lightning strikes, flexible flash drives, and thermoelectric devices, which generate electricity from heat. It is a polymer that is similar to Plexiglas due to its inexpensiveness and ability to be used in a variety of products, but is able to conduct electricity. Polymers are composed of a central skeleton of monomers and depending on the polymer, contain side chains that are are attached to it known as “pendant groups”. Pendant groups in radical polymers are the main reason for electrical conductivity, because the pendant groups are able to let charge pass through, resulting in a current. The process of creating a radical polymer is known as deprotection, this process includes replacing a hydrogen atom in the pendant group with an oxygen atom. Electrons in an outer shell are usually paired with another, but in this polymer, the new oxygen atom is left without a pair and therefore, makes it capable of transporting electrical current.
Connection:
This article relates to our unit on macromolecules, specifically on polymers as well as our short unit on the six most important elements. We learned that polymers are composed of a chain of monomers and some with extra chains branching off. There is a vast number of polymers that make up life and surprisingly they are built from a series of about 50 kinds of monomers. Just as we studied the Hydrolysis reaction and Dehydration reaction which could create energy from the lysis or fusion of bonds, scientists used the process of deprotection in the side chains of polymers to make it more electrically active. They did this by replacing a hydrogen atom within a pendant group with an oxygen atom which makes its nucleus unstable. A hydrogen atom has one electron in its valence shell and an oxygen atom needs two electrons in order to fill its valence shell. This unstable particle is now an ion, a charged particle, thus, it is able to create a current.
This article relates to our unit on macromolecules, specifically on polymers as well as our short unit on the six most important elements. We learned that polymers are composed of a chain of monomers and some with extra chains branching off. There is a vast number of polymers that make up life and surprisingly they are built from a series of about 50 kinds of monomers. Just as we studied the Hydrolysis reaction and Dehydration reaction which could create energy from the lysis or fusion of bonds, scientists used the process of deprotection in the side chains of polymers to make it more electrically active. They did this by replacing a hydrogen atom within a pendant group with an oxygen atom which makes its nucleus unstable. A hydrogen atom has one electron in its valence shell and an oxygen atom needs two electrons in order to fill its valence shell. This unstable particle is now an ion, a charged particle, thus, it is able to create a current.
At the end of the article, they mention that the deprotection process can lead to four distinct chemical functionalities of the radical polymer, and two of them are especially promising for increasing the conductivity of the polymer. What are these two functionalities and why would they increase the conductivity of PTMA?
ReplyDeleteThere aren’t many articles that specify as to what the four distinct chemical functionalities of radical polymers are but based on ACS Publications (http://pubs.acs.org/doi/abs/10.1021/ma500626t), the two most promising functionalities are the stable free radical and the corresponding oxoammonium cation. I’m not entirely sure as to how they both increase the conductivity but as I stated in my connection paragraph, by replacing a hydrogen atom within a pendant group with an oxygen atom, the nucleus will become unstable. Since Hydrogen atoms have one electron in their outer shell and oxygen atom need two electrons to complete their shell, this will lead to an unstable ion. Thus, it is able to create a current because ions are charged particles. As scientists and researchers alter the conditions of these reactions through deprotection, they are getting closer and closer to understanding the chemical properties of radical polymers.
DeleteIs the polymer PTMA commonly found on Earth? Also, does deprotection occur naturally in the environment?
ReplyDeleteIn response to your question, PTMA is not a naturally occurring substance. PTMA is a product created by scientists as a result of the experiments they conducted. So it is not necessarily “commonly found on Earth.” But, scientists think this will be the next fuel source because it can be made in a great abundance. I’m not entirely sure, but I think Deprotection does occur naturally in an environment. Deprotection is just a simple oxidation reaction and is basically a chemical reaction. According to Wikipedia (http://en.wikipedia.org/wiki/Protecting_group) a protecting group is a substance or molecule that must be altered in order to prevent a chemical reaction with another substance. When the protecting group changes back into its original form, the process is called deprotection. Since chemical reactions occur frequently in nature, I believe that deprotection also occurs in the environment.
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