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While it is used all over the world as a light packaging and insulation material, EPS (expanded polystyrene) is a problem as waste. This is why VTT Technical Research Centre of Finland is currently developing an affordable and environmentally friendly alternative for polystyrene from PLA bioplastic, which is derived from organic sources. The annual production volume of EPS is 5–6 million tonnes per year. Usually this non-biodegradable material ends up on waste tips or is disposed of by burning, which results in compounds that are hazardous to health. PLA (polylactide) is a bioplastic made from renewable materials with the help of lactic acid. VTT is investigating methods of foaming bioplastics to make beads that are further refined into products such as insulation sheets, using methods typical of EPS manufacturing processes. The expansion of the bioplastic by foaming is carried out with consideration for the environment, using carbon dioxide. The density and heat insulation properties of the new biomaterial are similar to those of polystyrene. VTT plans to take its development work closer to industrial processing and to proceed from laboratory work to factory testing. Therefore, in order to collaborate in this development it is now looking for partners from among companies operating in the field. PLA products similar to polystyrene already exist, but their problem is their high price. In collaboration with companies operating in the field, VTT will be looking for new and more efficient production methods to enable the manufacturing of affordable products. VTT is also developing a process for PLA based on extrusion foaming, in order to replace polystyrene in traffic and packaging applications, for example.

Gold nanoparticles smaller than 10 nanometers spontaneously self-organise in entirely new ways when trapped inside channel-like templates. A new study shows that this feature could facilitate easier nanoscale manufacturing of biosensors and plasmonic devices with intricate, high-density surface structures. Generating surface patterns at scales of 10 nanometers and below is difficult with current technology. An international team, led by Joel Yang from the A*STAR Institute of Materials Research and Engineering in Singapore, is helping to circumvent this limitation using a technique known as ‘directed self-assembly of nanoparticles’ (DSA-n). This approach takes spherical nanoparticles that spontaneously organise into ordered, two-dimensional films when inserted into lithographically defined templates. The templates impose geometric constraints that force the films to organise into specific nanoscale patterns. Most patterns produced by DSA-n, however, are simple periodic arrangements. To broaden this technique’s capabilities, researchers are exploring ‘structure transitions’ that occur when template constraints become comparable to the size of the nanoparticles. At these dimensions, the small spheres can dislocate from typical periodic positions and reorient into unpredictable new geometries. Previous studies have used real-time video microscopy to capture structure transitions in microscale colloids, but direct imaging of sub-10-nanometer particles is nearly impossible. “That’s where we came up with the idea of using templates based on channels with gradually varying widths,” says co-author Mohamed Asbahi. “With this system, we can track the self-assembly of the nanoparticles according to the space accessible to them.” Using electron-beam lithography techniques, the team carved out an array of inward tapering trenches designed to fit 1 to 3 rows of gold nanoparticles. After depositing a monolayer of 8-nanometer particles in the template, they used scanning electron microscopy to identify any emergent width-dependent patterns. Between periodically ordered rows, the researchers saw clear evidence of transition state zones — regions where the tiny spheres buckle […]

VISI software was at the heart of a mould maker’s recent move to new 6,500 square foot premises. KA Tooling say VISI gave them confidence to invest in additional CNC machines and move to larger premises to meet the growing demand for their custom made injection mould tools. According to Director Alex Hill, VISI ensures jobs are finished on the machines much faster than with their previous software. “When we first installed VISI the efficiency gains in terms of speed and accuracy enabled us to take on more work, but we were becoming limited by the size of our premises and number of machines.” They recently moved to their new larger more efficient premises, Alex says they utilise VISI to the full – four seats of VISI Modelling and VISI Machining, a VISI Viewer package, and a seat each of VISI Mould, Electrode, Flow-Lite and Compass Technology. “We maximise technology to reduce costs and improve turnaround, especially in the aluminium market, and VISI enables us to achieve this with top quality moulds. The days of producing aluminium tooling to get the customer’s product to market and then replacing it with a P20 steel tool after around 50 shots off it, have gone. We make aluminium tools where customers produce over half a million mouldings.” As KA Tooling now manufacture more than 100 high precision tools a year, Alex Hill says VISI’s Compass Technology is particularly important for automating the process of manufacturing bolster sets. “It’s rules based machining, by setting parameters for different features within a bolster plate. Thanks to Compass, we’re now using just one machining centre, rather than two, to produce bolsters. “We offer an expedited service – customers come to us because we can offer a two week turnaround from start to finish, whereas most companies quote […]