The new packaging paradigm: implications for polyolefin resins
As plastic manufacturers move towards more sustainable packaging solutions, how is this poised to impact the use of polyolefin resins?
By Roberto Ribeiro, President, Townsend Solutions
A fast-growing number of major retailers and brand owners are dedicated to meeting goals around reusable, recyclable, or compostable packaging and these initiatives are fueling a global re-think of packaging design. There is also a significant push towards sustainable solutions by the packaging companies themselves, who are driving strategies that include light-weighting, downgauging, adopting recycled and renewable content, extending shelf life, reusability, and recyclability.
Environmentally-conscious consumers, especially those who recycle, expect to see some recycled content in their packaging. Consumer requirements like this are at the core of packaging design innovation at brand owners like Unilever who reports their sustainable living brands segment to be growing 30% faster than other business areas.
Increased usage of recycled content has implications for consumption of virgin resins going forward. However, it Is difficult to generalize on this trend. Value chain participants need to thoroughly analyze the packaging market down to individual applications to see which areas might represent threats, and indeed opportunities, to their existing value propositions. See the following graphic for a detailed Townsend Solutions analysis on an application basis for polypropylene resin.
Resins based on renewable content, be they biodegradable or otherwise, are also coming into the picture. Here, thorough life cycle analyses are called for to ensure that these on the surface environmentally friendly offerings are truly so taking into account the entire production process, performance of the material in use, and true biodegradability once the product enters the waste stream.
The move from multi-material, non-recyclable structures to recycling-stream-compliant multi-layer structures based on individual resin families such as polyethylene (PE) is gathering pace based on recent developments as evidenced by an innovative formulation of PE resins to create a new sustainable all PE laminate solution with flexible packaging applications from Dow Chemical. These structures need to deliver moisture and moisture-plus-oxygen-barrier performance for food packaging and represent the cutting edge of flexible packaging advances.
Single-material, multi-layer flexible packaging structures represent a potential bonanza for polyethylene-based resins, in particular for pouches. Here, ethylene chain resins, not only polyethylenes such as LDPE and LLDPE themselves, but also polyolefin elastomers and plastomers (POEs, POPs), and adhesive resins such as EMAA and EBA will be positively impacted because this entire set of products delivers to the convertor and brand owner flexibility to deal with different properties when applying them in combination. To boot, that can realize a final product that is recyclable. When a layer comprised of recyclates is added, the addition of appropriate compatibilizers can enhance performance, again, thereby also positively impacting this market segment.
Brand owners such as PepsiCo are making tremendous investments in sustainability initiatives encompassing product development. For example, the company is incorporating mineral content in flexible packaging layers (calcium carbonate) to reduce the carbon footprint of the latest potato chip bags based on a PE structure instead of the traditional metallized oriented PP film-based structure. Upcycling, compaction (how do get more product to fit in a packaging container), exploring biaxially oriented PE films, and ways to promote biodegradation are also on the radar at brand owners. On the rigid packaging side of the business, companies like Keurig are also working towards improving recyclability, methodically shifting production of their K-Cup® pods from a PE-based multilayer structure to an all-polypropylene structure with a paper filter and aluminum lid.
The use of compatibilizers is another area being fueled by the need to improve recyclability. Compatibilizers are additives that allow two otherwise noncompatible polymers to blend together and deliver enhanced performance in the final product compared to either polymer in its own. These additives also facilitate plastic recycling as many of the plastic blends collected for recycling do not easily mix with or adhere to each other.
Conversion from rigid to flexible packaging is a continuing trend in the industry. New resins and structure designs are making recyclable flexible barrier packaging a reality, including development of new types of pouch fitments to further support new flexible applications. This is being supported by new legislation that is driving innovation to allow for tethered caps and closures to ensure that they enter the recycle stream properly.
There is a continued switch in beverage caps and closures from two-piece to one-piece construction to improve manufacturing efficiency and closure recyclability. Easy-opening, improved tamper evidence and one handed operation are also increasingly important design factors, especially in the growing water bottle market.
“Single-material, multi-layer flexible packaging structures represent a potential bonanza for polyethylene-based resins.”
Other waste reducing measures being evaluated include influencing flow properties with additives in formats like pillow pouch and bag in box to improve evacuation in applications like soaps, detergent refill pouches, liners, transfer totes, and industrial food service.
Film producers, package makers and brand owners are collaborating to develop food packaging with the durability (stiffness/toughness balance) and other properties that are required for the rigors of today’s consumer and the e-commerce supply chain. The consumer of today is very different than the consumer of 20 years ago, the younger generation’s typical lifestyle is busier and more health conscious, which often require performance packaging – smaller-sized on-the-go packaged products delivered quickly, consumed easily and disposed of efficiently.
Designing for the new “on-demand” format requires an expanded set of design considerations; performance (barriers, sealing, abuse), format (flexible, sachet, pouch, etc.), materials (mono or multi-layer), printing (branding, consumer interaction), pack sizes/case sizes, fill and transport considerations and disposal/end-of-life.
Better performing flexible packaging solutions, especially seal integrity and abuse resistance so products arrive at the consumer’s door intact, will be a must to support the more rigorous e-commerce supply chain.
Demand for rigid industrial packaging like drums and intermediate bulk containers (IBCs) is expected to increase at they find new utilization in shipping goods in bulk to online sellers, who will then repackage into smaller packages for customer orders.
E-commerce means more shipping, and more trucks on the road. Shifting loads in transit are a serious safety hazard and globally damaged goods account for billions of dollars in losses annually. Optimizing stretch film applications can help reduce damage during shipping, reduce wrapping cycle time and in some cases can reduce the amount of stretch film required to attain optimal and consistent containment force. Growing attention to sustainability and social responsibility, in addition to regulations such as the European Union’s Directive of Road Worthiness which became effective in 2018 will surely drive the focus on improving cargo safety and ultimately innovation in containment films (stretch films, collation films, stretch hoods).
Packaging trends for sweets and snacks include new formats for old favorites that incorporate rebranding and smart enhancements to encourage consumer loyalty and engagement, smaller format packaging for solo snacking and downsized portions, and packaging to accommodate multi-part contents for things like yogurt with stir-in granola.
The PET packaging sector is focused on engineering packaging based on today’s very consumer-driven market, which has shifted to a significant, very health conscious and convenience oriented segment of the global population. There are five areas of action:
- Shelf appeal
- “Right-weighting” vs. light-weighting (premium feel)
- Decreasing package size for convenience (trend shifting to 300 ml capacity and slimmer designs)
- Packaging must match the message (brand awareness)
There’ is s a push for SMART packaging like:
- Glow in the dark sleeves
- Photochromic (sun activated) and thermochromic (heat activated) labels
- Intelligent labels that can be scanned with a phone to access full product info
- Intelligent polymers – packaging changes color as product ages, indicating shelf life
Preform manufacturing is focused on high speed, high output and many companies are moving to the use of one single preform that can make 12 different products, thereby cutting time and cost of production.
With the growing trend toward health awareness, carbonated soft drinks (CSD) has lost market share, but it is still a significant business, and PET is coming out on top as the popular packaging format choice. More focus is going into developing greater beverage sophistication and variety as well as healthier attributes with less sugar and fewer preservatives for these products. Consumers are attracted to CSD bottle formats that fit their image and lifestyle with shapes and designs that attract their attention. PET is already a 100% recyclable, cost effective material that keeps beverages fresh, safe and flavorful – so it’s all about the packaging!
“Designing for the new “on-demand” format requires an expanded set of design considerations addressing performance, format, materials, transport considerations and the product’s end-of-life.”