VTT developing green alternative for polystyrene
It is also developing a process for PLA based on extrusion foaming, to replace polystyrene in packaging applications for food such as fish.
Methods typical of EPS
PLA is a bioplastic made from renewable materials using 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 (expandable polystyrene) manufacturing processes.
Antti Ojala, research team leader, VTT, told FoodProductionDaily, it wants to work more with industrial processors, taking its findings from the laboratory to the factory floor, and is looking for partners to collaborate with.
He said PLA products similar to polystyrene already exist, but their problem is their high price.
“PLA is well known but unlike five years ago it is already at the level where manufacturers can use it in mass production,” he said.
“We have been working on extrusion and particle foaming for several years. The main benefits of EPS are it has good properties, it is sustainable and it has become price competitive.”
According to VTT, the annual production volume of EPS is up to 6m tonnes per year. Usually this non-biodegradable material ends up on waste tips or is disposed of by burning, which leads to compounds that are hazardous to health.
Ojala added VTT has received funding to go ahead with the project from companies in Finland so far, and it is expected to be complete the project in the summer of 2016.
Bioplastic foaming using carbon dioxide
“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,” he said.
“We are mainly working with Finnish-based companies including StyroChem which produces Expandable Polystyrene (EPS) and we are hoping to partner with BASF chemical company.
“PLA can be used for storage or transporting foods like hot meals to fast food restaurants, or to wrap snacks to keep them warm or to keep products cold, such as fish boxes when they are being transported.”
He added there are a couple of examples in the market right now in Australia and Europe, but they are expensive products.
For example to increase recycling rates for EPS, NSW Environment Protection Authority (EPA) in Australia and the Australian Packaging Covenant (APC) issued grants last year to 19 organisations to a total value of $933,000 to build new EPS recycling infrastructure across NSW.
The grants will enable the purchase of EPS recycling equipment, such as cages, shredders and compactors to collect and reduce the volume of EPS to make it economic to transport and eecycle back into plastic products. The program will recycle an additional 1,183 tonnes or 59,000 m3 of EPS per year.
“The next stage for VTT is to deliver this price competitive process looking for new and more efficient production methods to enable the manufacturing of affordable products,” said Ojala.
