Interview: The dispersion games

Based on article published in the November/December issue of European Rubber Journal magazine.

New York-based imaging company Nanotronics has developed an advanced optical microscope for analysing surface properties of rubber products, dispersions and coatings.

In addition to being able to see things you can now understand what you’re seeing, Putman explained.

According to Putman, with the new device, scientists and engineers can now go in and tag or label something that they know has a specific feature.

“It gets built into a training system so when they have done this in production it will automatically tell you what is going on and whether the problem is in your mix, your moulding process or your extrusion process,” he added.

The early adopters of the technology are tire companies and rubber compounders.

German tire maker and automotive supplier Continental AG purchased the technology in June, while early users include compounders such as Altran, and dispersion companies such as Flow Polymers.

Companies that make fillers such as carbon black or silica can also be the potential users of the system.

Also, said Putman, makers of automotive parts such as seals, gaskets, wiper blades as well as other industries such as medical devices, can make use of the device.

So what does this new device bring to the market, which is not out there already?

“What’s out there already, like rheometers or viscometers give you information on whether you have a good batch or a bad batch; but they don’t tell you why.

“With them, you have to use a lot of correlation and figure out why you don’t have a good batch,” explained Putman.

With the 3D device, he went on to say, “since we are looking at something and we are tagging it – through the use of artificial intelligence and automation – you could be very specific.

“This device tells you what the dispersion is, for either carbon black, silica, nanotubes, graphene and other nanofillers. So, with that, you can adjust mix cycles or your compound.”

The natural intuition when mixing a compound is to do your best to guarantee that the filler is well dispersed. Simply mixing for a longer time does achieve this.

The new device, he added rapidly provides information about how well any of the fillers in a complex compound are dispersed in isolation of other physical properties.

“The combination of accurate classification and high resolution takes the subjectivity out of setting a mix cycle or troubleshooting a dispersion issue,” Putman said.

The device can also address the over mixing-problem and production of a bad batch.

“With nSpec 3D it is possible to set a mix cycle based on a much closer approximation of the optimal mix time. There is no reason to mix longer than you need to,” said Putman.

The device can also allow the use of fillers that have previously failed to be effective in rubber but have great potential.

“Carbon nanotubes have been a challenge. Even some silicas are still a compounding challenge, and to be able to quantify that in a matter of seconds on the line, allows you to start to scale this for the first time.

“So it doesn’t just slightly improve yield or things, but it changes what’s possible and can move the industry to ways different from what they’ve been doing for the last 100 years,” Putman concluded.