Oriented Polyethylene: 5 Things You Need To Know

Presented by Robert Clare, NOVA Chemicals

Invention description

A new Biaxially Oriented HDPE based film that enables 100% PE mono and laminated recyclable structures to be produced on a wide range of print and conversion equipment at a scale that matches high volume applications, with consistent performance and excellent properties.

This presentation will educate the audience on the benefits of these materials, potential applications and sustainability credentials.

What's innovative about its concept and development.

Monomaterial all PE films and packages are being rolled out across the food and non food packaging industry at an increasing pace, where there is a desire to substitute the incumbent films with solutions that match the properties as closely as possible, and deliver the same package optics and consumer experience.

Moving away from legacy print webs such as BOPET and BOPP to cast or blown PE versions has been accomplished, but these packs can display different properties, and films handle very differently at all conversion stages.

What has been required is an improvement in key parameters, such as tensile strength, heat resistance and optical properties, which is where orientation technology has been useful.

What has been required is a solution that offers these benefits, but at a production scale that can match the usage of some of the big volume products sold in stores (e.g chips, candy bars, stand up pouches and many others)

Biaxial film production of BOPE is the answer to this demand, and that is where efforts were focused by NOVA and their partners.

BOPE has been available from a few BOPP manufacturers using LLDPE as the feed resin, but these films are limited in use due to the low melt temp and low tensile properties associated with LLDPE

Moving to HDPE as a feed resin was the obvious choice, but this posed challenges for the producers, as typical grades of this material do not run well at all on conventional tenter frame lines.

Over the last 3 years, NOVA Chemicals, Bruckner Maschenbrau??? and several film producers have collaborated in optimization of resin technology, equipment upgrades and process development to bring these films to commercial availability, and offer an option the MDO-PE films currently available.

Positive (measured and/or potential) impacts on sustainability.

BOPE films from our partners exhibit the required performance to enable substitution of BOPP and PET as the external print carrier web in laminated films, enabling fully recyclable structures to be created when paired with a suitable PE sealant film.

These materials have been used to make finished pouches on Premade and FFS equipment successfully, and show potential to be able to substitute the incumbent films on high speed flow wrap and lidding applications.

New versions of these materials are already under development, with mettalized, Low SIT (seal initiation temp) and peelable versions already at advanced development stage.

Other technologies such as cold seal application should pose no issue, and collaborative partners are being sought to do this work.