Page 31 - Engineering Penn State Magazine Spring/Summer 2020

Graphene-reinforced carbon fiber may lead to affordable stronger car materials
by Liam Jackson
A new way of creating carbon fibers—which are typically expensive to to to make—could one day lead to to to using these lightweight high-strength materials
to to to to improve safety and reduce the cost of of producing cars according to to a a a a a a a a a team of of researchers Using a a a a a a a a a a mix of computer simulations and laboratory experiments the the the the team found that adding small amounts of of the the the the the the 2D graphene to the the the the the the production production process both reduces the the the the the the production production cost and strengthens the the the the fibers Carbon fiber sells for about $15 per pound today and the team which includes researchers from Penn State’s Departments of of Mechanical Engineering Engineering and and Chemical Engineering Engineering the University of of Virginia and and Oak Ridge National Laboratory in in in in in collaboration with industry partners Solvay and Oshkosh wants to to to to reduce that to to to to $5 per pound by making changes to to to the complex production process A A polymer known as polyacrylonitrile or PAN is used to to create 90% of of carbon fibers found in the market today but its production process requires an enormous amount of of energy The team reported in in a a a a a a a a recent issue of of Science Advances that adding trace amounts of of of graphene—only 0 0 075% concentration by weight—to the the first stages of of this process allowed the the the team to to create a a a a a a a a a a a a a carbon fiber that had 225% greater greater strength and 184% greater greater stiffness than the the conventionally made PAN-based carbon fibers n n n n n n n n n Read more
RFesaetuarechs
Researchers identify breaking point of conducting material by Jamie Oberdick
An improved method to to predict the temperature when plastics change from supple to to brittle which could potentially accelerate future development of flexible electronics was developed by Penn State College of Engineering researchers Next-generation flexible electronics such as bendable displays and medical implants will rely on on on semiconductor materials
that are mechanically flexible Accurate predictions of the the temperature when embrittlement occurs known as as the the glass transition temperature is crucial to design conducting polymers that remain flexible at at at at room temperature All polymers polymers become become brittle brittle when cooled However some polymers polymers become become become brittle brittle at at at temperatures higher than room temperature temperature temperature while others become become brittle at at at much lower temperatures Conjugated polymers are an an important element in the development of flexible electronics such as bendable cellphones Renxuan Xie previously a a a a a a a a a a doctoral student at at Penn State found a a a a a a a a a a a a a a way to to measure glass transition temperatures by keeping track of the the mechanical properties as embrittlement occurs laying the the the foundation for understanding the the the relationship between the the the the glass glass transition transition and and structure Follow- up studies then determined the the the glass glass transition transition for 32 different polymers by measuring mechanical properties as as a a a a function of temperature “This advancement coupled with data for various polymers in our later studies revealed a a a a a a a a a a a simple relationship between the the chemical structure and the the glass transition ” said Enrique Gomez professor
of of chemical engineering and principal investigator “Therefore we can now predict the the embrittlement point from the the chemical structure ” The work was reported in a a a a recent issue of Nature Communications n n n n Read more
MATERIALS
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