"Super Plastic" Directs Heat Away for More Efficient Electronic Devices

Plastics are very manufacturable and light, but they have a main disadvantage of not transferring heat well. This is a problem in applications where plastics are encapsulating electronics and the electronic device is dissipating a lot of heat that cannot escape. This leads to poor performance and a reduced lifetime. A new 'super plastic' that can direct heat away from its source opens up a wide range of possibilities for making more efficient electronic devices. University of Michigan engineering professors Jinsang Kim and Kevin Pipe are leading teams that are using hydrogen bonding from two different liquid polymers to regenerate a continuous pathway for heat transfer. The plastic blend dissipates heat ten times better than its conventional counterpart.

Transcript

00:00:00 the major scientific breakthrough here is the fact that we have made the first step toward the thermal engineering of polymers plastics- some of their advantages the are they are very manufacturable they're very light the main disadvantage were addressing here is the fact that they don't transfer heat very well and that can be a problem for application say whether used to encapsulate electronics where electronic devices dissipating lot of heat and if the heat cant escape that means the electronic device gets very hot and when it gets hot its performance suffers and also it can have a reduced lifetime

00:00:31 we invented a way to be able to mix two different polymers together especially so they bond together really strongly and efficiently transfer heat the thermal conductivity of polymer is always very low thermal energy cannot find a strong enough connection to move through but we designed a sort of hydrogen bonding so polymer one and polymer two and a and b polymer has very strong hydrogen bonding so then you know we generate continuous pathway along the polymer thin film so that's the way we improved the

00:01:07 the thermal conductivity. The way our polymer blends are made is that we take two polymers in solution that means they're their mixed in a liquid and then we drop that onto a substrate so I onto like a flat piece of silicon or glass we spend that on that substrate to basically create a very thin coating we can utilize the good processability at the same time we improve the thermal conductivity by order of magnitude so it has a great impact. The ways that people have improve thermal conductivity in polymers in the past, one the main ones is to put filler materials in so they take particles of say silver aluminuma something that has a high thermal conductivity

00:01:44 and they mix it into the polymer the trouble with that is that you often need a a large volume of those filler materials in order to actually change the thermal properties and when you have that large volume you're changing other properties of polymers as well such as its electric conductivity such as it's a optical properties which may be really detrimental for a a particular application. The finding the main through the study we know what is the important to make the good connectivity so that we can transport the thermal energy

00:02:15 nicely the same principle we can utilize to design polymer film that has very large heat resistance so so heat transport will be very minimal like thin air film having very nice insulating property and it has large number of applications we can come up with there are many places that we could go with this there are other thermal properties they can also be tuned this represents the first step to really learning how to engineer polymer structure to influence the flow of heat so the discovery was made by a mistake we were just printing

00:02:49 thin films and we'll add the system around for longer time and then we just noticed that beyond certain film thickness were starting to obtain