Four paths to sustainability4 March 2019
GlobalData’s report, ‘Packaging Insights: Innovation Scenarios in Sustainable Packaging Materials’, gives the low-down on the four materials that could boost the industry’s eco-friendly credentials.
Sustainable packaging was once a niche that only a small minority of the consumers took a notice of. As a result, a small number of products boasted of how environmentally friendly their packaging was, and few consumers gave this factor any importance when shopping. However, more consumers are now becoming aware of the impact that packaging can have on the environment, and as a result, ethical packaging is now becoming a ‘must have’ quality when purchasing a product. This sudden interest in sustainability in recent years has been driven by more open discussion via social media, and increased government lobbying resulting in action against plastics such as plastic bags.
This increased focus on environmental impact is creating new opportunities for sustainable packaging materials. This report analyzes the role emerging sustainable materials can play in boosting material substitution in packaging markets, and the drivers and inhibitors affecting the impact of sustainable packaging materials.
Microfibrillated cellulose (MFC) is a renewable material made from cellulose fibres that are extracted from wood. Designed to outperform current oil-based materials like plastic, MFC has the potential to replace existing paper and board in food and drink cartons, primarily for milk, juices and soups; it is made from natural raw materials, with typical sources being softwood, hardwood and vegetables. Compared with traditional pulp, which is white, the sustainable material is transparent and looks like gel.
MFC works as a barrier for grease, mineral oil and oxygen, or as a biodegradable film that replaces aluminium in paperboard packaging. These uses have potential for varied markets, such as fast food, or long shelf-life products, including jams, sports drinks, sweets and snacks. MFC offers more than sustainability, and its numerous benefits include:
- strengthening and lightening fibre materials to reduce their use, without affecting performance
- providing excellent oxygen and moisture barriers
- its extraction from plant waste helping to cut down on sourcing
- being sturdier and less permeable to keep water and air out better than other paper-based materials
- its renewable barrier materials and high-strength properties.
However, a method has not been found that achieves MFC’s full potential at a low cost. Today’s technology also limits its ability to supplant plastic and, in addition to this, its hydrophobic properties are less effective at keeping out moisture than low-density polyethylene.
While using MFC is a niche practice, due to its limited production capabilities, GlobalData has forecast its uptake in 2021 for smoothies, tea and coffee, and juices, which had the highest demand.
A synthetic polymer, Polyvinyl alcohol (PVOH) can be used to make plastic bags that dissolve in water, making it the most widely used polymer for manufacturing water-soluble films. Uniquely, this material allows control over dissolution times for hot and cold water, and can even be formulated to be insoluble for some applications. Its diverse uses cover everything from film used in feminine-hygiene and adult-incontinence products to resin solutions in personal-care items, including eye drops and contact lens wetting solutions as a lubrication aid.
PVOH could replace the flexible bags and films used in household products, as its water solubility limits its impact on the environment post-use. The material’s other advantages are:
- being dissolved in the paperboard recycling process
- providing an excellent gas barrier when dry
- its extraction from plant waste, which keeps it competitively priced
- reduced transport costs and lack of packaging disposal, due to its ability to dissolve.
The material’s strong biodegradable credentials have bolstered its use in household items like films for laundry detergent. As a barrier film, it reduces the need for preservatives, serves as a printing substrate and increases the shelf life of products.
But PVOH’s solubility can actually play against its gas-barrier properties in humid conditions, limiting its use in food packaging. On top of this, pure PVOH is difficult to process and cannot be extruded or shaped with heat. Its production costs are also higher than the less eco-friendly options of plastics bags and films.
Ethylene vinyl alcohol
Ethylene vinyl alcohol (EVOH) boosts the oxygen and gas barrier properties for plastic containers. Mainly composed of carbon, oxygen and hydrogen, EVOH has no toxic gases when properly incinerated. In addition, its combustion heat is half of that used for polyethylene, posing little threat to the environment.
With its high barrier protection, the material is popular for food packaging to preserve gases, flavours and aromas. It is also resistant to hydrocarbons, oils and organic solvents, making it perfect for use between the inner and outer plastic walls of bottles, jars or tubes. As a result, EVOH is referred to as a multilayer-barrier technology that can be applied to fresh or dry-food packaging.
Although suited to a range of applications, EVOH’s environmental benefits can be hard to communicate to consumers as it is slow to biodegrade – or doesn’t at all. These plus points include:
- preventing oxygen penetration and helping food items to remain fresh while preventing premature decomposition
- its lack of odour, high chemical resistance and inertness, which makes many EVOH grades FDA-compliant; this gives it the potential to replace a number of films used in the food categories and plastic tubes in the cosmetics sector
- transparency and the ability to be microwaved
- increasing decomposition rates when blended with other compounds, such as PVOH.
Like other materials, EVOH has its fair share of problems. As well as losing its protective gas barrier when exposed to moisture, the material is expensive to produce and is difficult to recycle due to its combination with other layers, which make it gum up on reprocessing, creating holes in recycled polyethylene film.
EVOH is common in some markets, like Japan, and has the potential to make its mark on global flexible-packaging markets.
Polyethylene furanoate (PEF) paves the way for a rigid plastic made from vegetable raw materials. As a 100% bio-based and recyclable polymer, PEF can be used for bottles and films across multiple applications, including packaging soft drinks, water, alcoholic beverages, fruit juices, food and non-food products.
PEF performs better against heat than polyethylene terephthalate (PET), and it has superior barrier protection against gases, such as CO2 and oxygen, to increase the shelf life of packaged products. In fact, it is ten, four and two times more effective than PET at keeping out oxygen, CO2 and water, respectively.
A popular alternative to PET, PEF’s other sustainable and functional benefits include:
- its recognition from leading brands like Coca-Cola and Danone, which work with the manufacturer Avantium
- PEF’s 100% bio-based molecule
- being fully recyclable
- a higher mechanical strength that allows thinner PEF to be produced, cutting the weight and amount of packaging required for applications.
PET, PEF’s main competitor, has upped its environmental game with molecules that can be biosourced up to 30% and the development of a 100% bio-based version of the material. Its production costs are also lower, but concerns have arisen concerning PEF’s potential to contaminate the recycling stream by getting mixed in with PET products.
Despite strong investments in the advancing PEF technology, the material’s market applications remain somewhat limited; however, by 2021, the packaged-water sector will have the highest adoption rate for PEF out of the carbonates and juice sectors, according to GlobalData.
A more sustainable future
Sustainable packaging continues to face the challenge of convincing consumers that it is worth paying extra for eco-friendly products. Media coverage is becoming more widespread for this issue, but many consumers are struggling to embrace being ‘green’.
According to ‘Greendex 2014: Consumer Choice and Environment – A Worldwide Tracking Survey’, sustainable consumer behaviour decreased in the US, Canada, Japan, China and Germany across the 18 countries involved in the research.
Moving towards sustainable materials is more cost-effective for manufacturers in the long run, but prices will need to increase initially to cover the R&D costs for creating new materials and upgrading machinery, so it works with new types of packaging. Companies will also need to endorse better recovery and recycling ecosystems.
The use of sustainable and high-performance barriers will continue to improve, paving the way for contamination-proof packaging that puts consumers and producers’ food safety concerns to rest. Governments will, in turn, place more pressure on companies to start using sustainable materials. There is no doubt that the race is on to develop sustainable solutions in a bid to gain market share before alternatives swoop in and launch across mass markets.