With fossil-fuel based plastics film increasingly the focus of environmental concern, volatile cost and availability and, on occasion, political opportunism, viable compostable biopolymers in the flexible packaging sector is just a matter of time, reckons Sam Cole.
The European flexible plastics packaging sector is worth around €20 million, accounting for over 4 million tonnes of conventional film/annum. It dwarfs current demand for a non fossil-fuel derivative, estimated at no more than 200,000 tonnes/annum; a 5% share of the market that existing capacity is unable to fully service. On face value, the disconnect between such clearly contrasting statistics would seem sufficient to consign the biopolymer alternative to niche applications at best. On the contrary, however, it seems poised to become a serious contender and a viable alternative to anything from the supermarket carrier bag to a multi-layer co-extruded barrier pack for fresh coffee.
The same laws of supply and demand which, right now, seem to be so stacked against the biopolymer industry will eventually swing 180º, says Innovia Films business development & sustainability manager Andy Sweetman. “I think we’re going to have to accept that because of availability and ease of supply, our conventional fossil-based sourced materials are going to become more expensive. Correspondingly, as bio-plastic materials develop and start to achieve economies of scale, their prices will fall. No one can predict quite when, but we’ll see both outcomes happening for certain.”
Brand owners, however, are already starting to switch regardless of constraints on supply; Coca Cola’s ‘plant’ bottle incorporating 30% bio-plastic PET derived from sugar cane, and more recently Danone moving from PS to NatureWorks’ PLA for its Activa yoghurt pot.
At the same time, producers are stepping up manufacture. BASF has recently expanded capacity for its Ecoflex grade film in Ludwigshafen by 60,000 tonnes to raise total capacity to 74,000 tonne/annum. Innovia is responding to a year on year increase in demand for their cellulose-based NatureFlex (currently producing 30,000 tonnes/annum).
Meanwhile in Italy, Novamont is reporting that sales of its EN13432 compliant Mater Bi compostable biopolymer are up by 60% this year as a result of the national ban on conventional plastic carrier bags. Having already increased capacity by 80,000 tonnes, a further 50,000 tonnes will become available next year with the completion of a new €500 million production facility at Porto Torres.
Encompassing a broad family of starch or vegetable-based polyesters, nano-particles, fillers and additives, Mater Bi’s significant benefit is that it can be dumped within the same food, waste disposal stream, requiring no change to the existing recovery infrastructure. Research also confirms that collection rates, especially in the inner city, rise significantly when waste food is bagged up.”
National Non-Foods Crop Centre’s (NNFCC) head of materials for energy & industry Dr John Williams notes that major brand owners are converting their premium products onto bio-based materials, to send out the positive green signals. Hence the continuing work on multi-layer, compostable flexible packaging applications, such as SAFTA’s Naturene heat-resistant laminate, to use in place of conventional barrier films.
New compostable solutions
FKuR’s new BioFlex F1130 resin is being used by Manchester Packaging (USA) to produce the world’s first fully compostable dog waste bag. With a superior water resistance compared to starch based formulations it can easily be converted on standard PE-LD lines. “The straightforward conversion process and good printability were the decisive factors in choosing this material,” says Manchester Packaging Company CEO Charles R Armistead.
Suitable for multi-layer flexible packaging applications for snack-foods, BASF’s new Epotal Eco is the first compostable water-based adhesive certified by the TÜV German technical inspection agency. It offers all benefits of water-based adhesives and meets the European EN 13432 standard for biodegradable plastics, allowing the production of fully compostable packaging for the first time.
Innovia’s next-generation cellulose-based NatureFlex N913 upgrades sealability to provide an even more efficient barrier film to meet both food and household product packaging requirements, says Andy Sweetman. “Our aim is to get as comparable as possible with a conventional plastics solution plus the improved upon end of life advantages.
“The base material is a conventional NatureFlex NK transparent barrier 25micron film with a layer of bio-polymer on one face. You get the heat resistance and the barrier from the base NatureFlex and greater sealability from the bio-polymer on the other face.”