The race to replace per- and polyfluoroalkyl substances (PFAS) is on, driven by increasingly stringent regulations and standards regarding these ‘forever chemicals’, some of which have been shown to have harmful impacts on human health and the environment.
PFAS, however, have a plethora of diverse, useful, applications, and are therefore not easy to replace, particularly in high-end applications. There is lack of viable alternatives to fluoroelastomers and fluoropolymers in such applications, for example. Alternatives are starting to emerge, however, for example in PTFE-free flame-retardant additives.
Another example is Tosaf’s new PFAS-free additives. The Israeli additive manufacturer has developed processing aids for the extrusion of polyolefins that do not contain fluoroelastomers.
The first grade, AP9709PE EU, provides enhanced rheological properties which aid the flow of the extruded polymer. The second grade, AP9711PE EU, enhances optical properties including clarity and haze.
The fluoroelastomers-free additives can be used ‘without restriction’ in place of standard products containing PFAS, according to Tosaf. They are suitable for a wide range of film applications and meet the requirements of the US Food and Drug Administration (FDA) and the European Food Safety Authority (EFSA) for use in contact with food.
Tosaf performed laboratory tests to back its replaceability claims. It compared the processing properties of a metallocene LLDPE with those of two of its compounds: one containing Tosaf's standard fluoroelastomer-based processing aid (AP5645PE EU), and another with alternative PFAS-free additives. Results for flow behaviour ‘were largely consistent’, according to Tosaf, and the optical properties of the PFAS-free compound ‘even showed slight advantages’. The coefficient of friction of the PFAS- free film showed a ‘negligibly lower’ value.
The new additives are already being used in some of Tosaf’s customer applications, for example a 5-layer coex-line using 1 % of the AP9709PE EU additive in the outer layer.
“Compared to a standard PFAS-based processing aid, this enables a 5 C to 10 C lower melt temperature and shows a significant lower occurrence of melt fracture as well as improved optical properties such as haze,” Tosaf said in a statement. It added that the films can be printed, sealed and laminated without any problems.
“Tosaf has once again demonstrated that its expertise, combined with its state-of-the-art research, development and testing facilities, can deliver solutions that the market is looking for, but which were previously considered unthinkable,” concluded Tosaf's Chief Innovation Scientist Dr Evgeni Zelikman.