High oxygen barrier packaging by micronanolayer multiplication technology, and by replacing EVOH by PA
The micronanolayer co-extrusion process is an extrusion based process that permits to fabricate films or sheets with ten to thousand layers. In these conditions, the final layer thickness can vary from micrometric to nanometric dimension. The technology was available only at the industrial scale; nowadays mainly 4 to 5 laboratories around the world have developed it at the laboratory scale in order to validate it while its use needs important optimization that is time and material consuming. PIMM is one of these laboratories that studies the relationships between process, microstructure and final properties of polymers. It had also been shown in literature that polymer gas barrier properties could be improved by decreasing the gas barrier material layer thickness in co-extruded films using the microlayer multiplication co-extrusion line. When the thickness becomes sub-micrometric or nanometric, the gas barrier properties can reach factor from 4 to even 100.
PIMM experience is focused on EVOH and some other polymer (PLA, PBS, PBSA, MXD6, …) and also in the improvement of polyamide (PA) gas barrier properties. This new technology would allow to replace EVOH in PE/EVOH film by PA and or to reduce the EVOH content in LDPE-PA-EVOH-PA-LDPE structure also conferring to the film the possibility to be easier recycled (PE-PA films and also LDPE-PA-EVOH films are very difficult to recycle). Nowadays, no scale-up had been done. Consequently, PIMM should adjust the parameters taking into account the polymers supplied by WIPAK. The function would be achieved by interaction of the different layers. Customer acceptance could be an issue, if the term “nano” is used to describe the technology.