Sustainable packaging innovations – from paperboard to pulp

Sustainability in paperboard packaging

In the global paperboard packaging industry, demand has grown for sustainable materials with sufficiently high strength-to-weight properties to enable the reduction of packaging weight. This is being driven by both economic and environmental pressures, as organisations address key areas of the United Nation’s Sustainability Development Goals by developing innovative solutions that use sustainable materials and processes in their products, packaging and waste management systems.

Current paperboard manufacturing technologies generally rely on tree-based fibres. The cost of the paper industry’s benchmark grade of pulp — northern bleached softwood kraft (NBSK) — has increased considerably in recent years. This has partially resulted from concerns relating to the environmental impact of forest operations. Premium paperboard grades include solid unbleached sulphate (SUS) and solid bleached sulphate (SBS), containing ~80% virgin long and short bleached wood pulp. Bleached paperboard is typically coated with a thin layer of kaolin clay to produce a smooth surface suitable for printing [1].

Wood-free fibre compositions

As part of its sustainability goals, Kimberly-Clark Worldwide, Inc. is aiming to reduce the world’s use of natural forest fibre and increase its use of more environmentally-friendly alternative and recycled fibres.

In this month’s issue of the Materials World magazine, I discuss a UK patent recently granted to Kimberly-Clark Worldwide, Inc., which relates to wood-free fibre compositions for paperboard packaging.

The patent discloses a multi-layered paperboard structure with top, middle and back layers. The compositions of each of the layers are engineered with a blend that includes a relatively high proportion of non-wood fibres, such as bamboo. In a series of experiments disclosed in the patent, this new material was found to outperform conventional materials. This may provide packaging with enhanced properties for certain applications while supporting sustainability goals at an equivalent (or possibly lower) cost than conventional wood-based materials. Read the full article here.

More packaging innovations and the ISCC sustainability certification

The Institute of Materials, Minerals & Mining (IOM3) recently shared a news item that drew attention to the importance of ISCC PLUS (Institute of Sustainability & Carbon Certification) — a widely recognised international sustainability certification scheme, which verifies the quality and authenticity of the recycled material along the supply chain, from feedstock to final product [2]. Notably, Mars, Inc. is working with SABIC and Huhtamaki to incorporate recycled polypropylene — certified under the ISCC standard — into the primary packaging of some of its pet food brands in 2020, with expansion to other brands planned for 2021.

Green packaging material alternatives to plastic are being adopted by other multinational organisations. Last year, IKEA furthered its commitment to the cause by replacing its polystyrene packaging with MycoComposite™ — Ecovative Design’s patented biomaterials platform that uses mycelium as a self-assembling biological binder for agricultural byproducts [3]. The byproducts, such as hemp, husk, oat hulls and cotton burrs, are pressed into shape before being seeded with mushroom spores that sprout a mycelium root network, binding the structure together. A subsequent heat treatment is used to arrest further growth, forming a durable packaging material that is compostable [4].

Ribena is also set to use fully recyclable and biodegradable U-bend paper straws on its drink cartons. The straws, made by British manufacturer Transcend Packaging, are made entirely from paper pulp and are being trialled on Ribena cartons in Tesco stores across the UK. The drink cartons industry as a whole has experienced a dramatic improvement in recycling rates in recent years. In November 2020, the Alliance for Beverage Cartons and the Environment (ACE) announced that the recycling rate for beverage cartons in the EU28 rose to 51% in 2019 [5].

The UK’s only dedicated beverage carton recycling plant is based in Stainland, West Yorkshire and is capable of recycling 40% of cartons used in the UK each year. The plant is aiming to address the issue of waste material being sent abroad and the associated emissions through exports, due to the otherwise lack of recycling capacity in the UK.

In addition to product and packaging selections, it’s also important to consider implications on waste management systems, which support the adoption of new recyclable materials. For example, in May 2018, McDonald’s — which uses approximately 1.8 million straws every day in the UK — responded to a petition signed by almost 500,000 people by switching from plastic straws to paper-based and recyclable alternatives. In August 2018, however, McDonald’s stated that the new straws were not to be recycled, which perhaps indicates that the entire lifecycle of the new materials, including the end of life or waste phase, had not been properly considered [6]. With this in mind, there appears to be a need for further technological developments in waste management to support the eco-friendly transitions being made with regards to products and packaging, to achieve a full-circle economy.

Exporting waste overseas for recycling is a problem that is also being addressed by SpaceBlue Ltd — a Manchester-based start-up that has developed a novel solution to the several thousand tonnes of vehicle tyres being exported abroad for recycling each year. The SpaceMat® is made up of 80% recycled rubber and 20% graphene-enhanced natural rubber. The addition of graphene is used to produce hardwearing floor mats as it provides greater than a two-fold increase in the compressive strength of rubber [7]. This solution appears well thought out, as it overcomes pressures associated with waste management through the creation of new high-quality products which not only make use of the recycled materials but also which may serve a different but long-term purpose.

Another interesting development comes from one of our clients, Switch Packaging, which creates bespoke pulp solutions to replace plastic packaging.

For advice on protecting innovations in packaging, get in touch us.

[1] Patent Publication GB2557052 — Wood-free fibre compositions and uses in paperboard packaging

[2] Petfood packs start to aid circular economy

[3] Ecovative Design’s MycoComposite™

[4] IKEA Replaces Styrofoam With Mushroom Bioplastics

[5] ACE reports increased recycling rate for beverage cartons

[6] Why the hell can’t McDonald’s recycle its paper straws? It’s complicated

[7] SpaceMat: graphene’s answer to recycling tyre rubber launches to market