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Automotive bioplastic

A University of Toronto research project aims to produce a bioplastic using shellfish that will be used to make vehicle parts.


Canadians love their seafood.

Fisheries and Oceans Canada data shows each of us eat an average of 23.1 kilograms of the stuff annually. It’s also an industry worth a yearly $2 billion of GDP. Shrimp and crab account for 23% of this consumption, but apparently we’re wasting some of their most useful parts. Those potentially “harmful if swallowed” shells could be used to make a wicked soup stock, yet more often than not, they end up in the trash. But what if they were ingredients in a new bioplastic that could be used to make automotive parts that are lighter, cheaper and biodegradable?

Sounds unlikely – except to Aaron Guan. The master of science candidate at the University of Toronto and his supervising professor, Hani Naguib, are making waves in the “seafood as bioplastics” world. Their project aims to show how fibres extracted from shrimp and crab shells will strengthen other naturally produced bioplastics and it’s attracting some attention.

Auto21, the automotive innovation support network based in Windsor, Ont., showcased technologies developed in part by graduate students during its TestDRIVE competition held in conjunction with Canadian Manufacturers & Exporters’ 2012 Small Manufacturing Summit. Guan earned a $10,000 scholarship for his and Naguib’s efforts.

Bioplastics development is a relatively new pursuit that involves strengthening plastics with naturally extracted polymers.

Nanocrystalline cellulose (NCC), a tree extract, has had such an impact that forestry research firm FPInnovations and Montreal-based paper-giant Domtar teamed up last year to invest in a $32.4 million transformative-technologies pilot plant at Domtar’’s Windsor, Que. pulp and paper mill.

The plant will have the capacity to produce almost a tonne of NCC a day to make specialized coatings and advanced materials out of biodegradable hardwood chips.

Environmental impact – or lack thereof – encouraged Guan to get involved with the University of Toronto project.

“My biggest motivation was replacing products derived from petroleum-based plastics with a new product that’s sourced from a waste material and completely biodegradable,” he says.

The “Recyclable, Lightweight Polymetric Nanocomposites” project is investigating the development, processing and characterization of recyclable and biodegradable polymers (polylactic acid) with nano-particles (such as carbon nano-tubes) to develop lightweight automotive components.

“When Dr. Naguib approached me, it sounded like a project that could have a major impact on the world stage,” says Guan. “I wanted to be involved in something that could be of major benefit to the environment and economy; that wouldn’t be buried in the back of the newspaper.”

The fibres in shrimp and crab shells, called chitin nanowhiskers, form a base-strengthening material. They’re combined with polylactic acid and both go through induced cellular morphology to create what could be the world’s newest bioplastic.

A lighter, stronger material
Guan’s research suggests the material has a higher strength-to-weight ratio than conventional plastics used in most automotive components, providing higher mechanical strength without the aesthetic flaws or deformations that occur at lower densities. Mechanical properties can be engineered to suit various strengths, stiffness and weight requirements by varying combinations of chitin nanowhisker and polymer content. The material is also completely renewable and sustainable since it’s derived from fishing industry waste.

Commercialization isn’t imminent, but a number of low temperature, low humidity applications look promising.
“Assuming we can finish the research by the end of next year, the next step would be analyzing the scale we could achieve,” says Guan.

The plastic would be best used for components such as dashboards and interior door panels. And it would be less costly than traditional plastics because the biomaterial wouldn’t be based on oil prices, which Guan notes “are going crazy.”

Indeed, a barrel was going for a little less than $80 four months ago but at press time, it was in $106 territory.

Meanwhile, the price of polylactic acid is coming down. Guan’s supplier, NatureWorks, the Minnesota-based Cargill subsidiary, has cut its price in half since 2008.

As work on the U of T project continues, Canadians can do their bit to ensure supply meets demand for the new material by continuing to enjoy their favourite crab and shrimp dishes.

This article appears in the March 2012 edition of PLANT.