Life in bio-plastic, it's fantastic

Unpacking the bio hype from plastics’ feedstock to end of life with Hannah Friedman and Keeton Ross

Turns out, there wasn’t a great future in plastics. As the all too ubiquitous container of our society, plastic shapes how we eat, what we wear, and quite literally forms our bags, boxes, homes, cars, and most things in between (e.g. fish).

Our prior penchant for plastic has driven a burgeoning petrochemical industry that sucks up 14% of global oil use as the feedstock. Within the last two decades, global plastics production has doubled to 460M tonnes and jumped to ~3% global GHG emissions to meet our insatiable demand.

The real dirty wrinkle with plastics cuts deeper, past production emissions into mismanagement at the end of life. The damning figure is our global recycling rate, which has decreased from ~9% to just over 5%, accompanied by headlines on the epic failures / need to expand composting infrastructure and overflowing landfills that recently ignited during heat waves. Though, there’s a glimmer of hope for a new lease on plastics’ end of life. India and other countries have announced bans on some formats of single-use plastics, and California went one step further requiring all packaging to be recyclable or compostable by 2032. In funding, we’ve tracked $1.6B of venture capital deployed towards biobased packaging and chemicals innovators since 2020, alongside a recent spike in M&A activity for composting (e.g., Generate Capital acquiring Atlas Organics).Framing plastics’ emission scope can get quite nuanced depending on where you draw the LCA line.

There are three major levers to plastic decarbonization:

1) Raw materials e.g. feedstock

2) Manufacturing e.g. process energy

3) End of Life e.g. recycling, composting, landfill

Source: Prevented Ocean Plastic

With the sweeping caveat that reduce, reuse, recycle always reigns true, bioplastics have entered the plastic decarbonization ring pulling on 2 out of the 3 decarbonization levers: using a 1) biobased feedstock and/ or being 2) biodegradable at end of life (more on this later). But bioplastics are hardly a shoo-in; the “bioplastics” space is rife with misnomers and confusion.

In this issue, we go plastic (it’s fantastic!) – where it costs us, where it’s changing, and how bioplastics are shaping some new reality. We’ll get to all that, along with genuine circular economy innovations, but first, let’s start with the basics.

Plastics 101: Where do they come from, and how are they made?

A plastic is a polymer (poly meaning many) made up of a repeating chain of monomers (mono meaning one). Chain together multiple monomers and you get a polymer - voila, plastic! Plastics vary in weight, color, melting points, density, and barrier properties (like permeability to oxygen or moisture), among other things. These properties depend on which monomers are used, their chemical structure, order of assembly, and presence of any other chemicals such as additives. Think of plastics as one complex recipe - you can get fluffier muffins with different ingredients.

Generally, plastics fall under two general buckets: thermoset (durable and retain their form under heat) and thermoplastic (soften and melt under heat). The thermoset and thermoplastic lines break out even further by their resins, conveniently numbered 1 through 7:

1: PET (polyethylene terephthalate) - food packaging, single-use bottles, polyester

2: HDPE (high density polyethylene) - milk cartons, detergent bottles

3: PVC (polyvinyl chloride) - plumbing pipes, credit cards, medical tubing

4: LDPE (low density polyethylene) - garbage bags, plastic wraps, grocery bags

5: PP (polypropylene) - straws, prescription bottles, packaging tape

6: PS (polystyrene/ styrofoam) - takeout food containers, product packaging

7: Everything else! - a super ambiguous catch all

Not full on alphabet soup yet? The various monomers that add up to create polymers are also often referred to by their acronyms. MEG (monoethylene glycol) + TPA (terephthalic acid) = PET. But that’s (almost) enough chemistry for today. Most important to recognize is that depending on their properties, certain plastics may be more recyclable than others. PET (#1), HDPE (#2) and increasingly PP (#5) are the most recyclable of these traditional plastics, which is a good thing given their relative abundance in the market.

The life and death biography of a plastic

How do liquified dinosaur fossils resurrect as your Poland Spring bottle? Breaking down the plastics value chain is a bit of a Pandora’s box, so we’ve simplified it here (in yellow):

A simplified view of the (Bio)Plastics value chain (Source: CTVC)

Conventional fossil-based plastics generally follow the path of:

  • Fossil fuel feedstock: starting off with naphtha (oil-based) or ethane (liquid natural gas)
  • Refining, cracking: using high heat and pressure to break feedstock down into monomers and precursors (e.g., PX, ethylene
  • Polymerization, compounding, additives: chemically combining monomers to form polymers (e.g., PET, HDPE)
  • Extrusion, pelletization: melting and forming the polymer into tubes, sheets, films, wires, or pellets, etc.
  • Conversion, bottling: form-fitting the plastic into final products e.g., bottles or bag
  • Distribution & use: distributing the products across retail channels for use
  • End of life: disposing the final product through recycling, or sending to landfill  

Remarkably, this conventional fossil-based plastics value chain translates largely identically for the bioplastics value chain, as represented in blue. Now keep this value chain framework in mind as we get down in the *weeds* of bioplastics!

Putting the bio in plastics

Bioplastic can mean that a material is biobased. Bioplastic can also mean that a material is biodegradable. These terms are not mutually exclusive; biobased refers to feedstock whereas biodegradable refers to the end of life of the material. Therefore, a petroleum-based plastic that is biodegradable counts as a bioplastic (e.g., PBAT), as does the vice versa of a biobased plastic that is not biodegradable.

Mapping plastics cos across the bioplastics spectrum (Source: Closed Loop Partners, European Bioplastics)

As we’re ever eager to put the world into a 2x2, the complete universe of bioplastics comprises 3 of 4 quadrants - materials that are biobased and / or biodegradable. The lower left quadrant of conventional, fossil fuel-based plastics are excluded from the bioplastics definition (le duh) though most are recyclable.

The majority of frontier bioplastic innovators bridge the intersection of biobased and biodegradable, doing double duty to push the envelope of bio-benefits.

✅ Biobased feedstocks, ❌ Non-biodegradable

Materials: Bio-PET, Bio-PE, Bio #1-6
Companies: Resource Chemical (producing biobased FDCA), Virent*, Origin Materials*

✅  Biobased feedstocks, ✅ Biodegradable

Materials: Chitin, PHA, PLA, PEF (if MEG is renewable)
Examples: Genecis (producing PHAs from biogas of AD), Bloom Biorenewables (lignin-based biopolymers), Erthos (novel biopolymer from ag wastes), Mango Materials (producing PHAs from landfill methane), RWDC (producing PHAs), Shellworks (bacteria-produced “fat-like substance” to create rigid bioplastic and other chitin-based biopolymers for dissolvable films), FullCycle Bioplastics (producing PHAs from food waste), Cruz Foam (styrofoam-like bioplastic from shrimp shells), Plantic*, Total/ Corbion*, Futerro*, NatureWorks*, Danimer Scientific*, Origin Materials*

❌ Petroleum-based feedstocks, ✅ Biodegradable

Materials: PCL, PBAT, PBS
Examples: TIPA (⅔ biobased and compostable flexible films), PTT MCC Biochem* (producing PBS), Better Packaging Co (utilizes PBAT among other mixed biopolymers in compostable flexible films), Kintra Fibers (producing PBS-like material)

❌ Petroleum-based feedstocks, ❌ Non-biodegradable

Materials: Conventional plastics #1-6 (PET, HDPE)
Examples: Dow Chemical*, LyondellBasell*, Exxon Mobil*, SABIC*, ENI*

*Denotes public, JV, or acquired companies

Feedstocks: where it all begins

The big buckets of biobased feedstocks are sugar, starches, fats and oils, woody biomass, and other organic waste (such as food diverted from landfills). For the former, there are sources of both virgin feedstock (e.g., trees and rows of corn grown specifically to produce bioplastics) and waste feedstock (e.g., rice husks or leftover corn stover after harvesting). Each biobased feedstock fundamentally varies in scalability, cost, market maturity, geographic distribution of availability, expected life cycle analysis impact, and ease of useability in downstream processes.

How do you take these biobased feedstocks and convert them into useful materials, whether as traditional recyclable plastics or compostable biobased plastics? Predominantly, these conversion pathways are chemical (e.g., synthesis, polymerization) and biological (e.g., fermentation). Then, taking material inputs to a finished packaging product generally follows the same value chain post-polymer.

Biopolymers produced by various processes (Source: Current progress on bio-based polymers)

End of Life: where it all ends (and begins again)

Now that we’ve got biobased feedstocks on lock, let’s unpack the biodegradability’s own set of bioplastic caveats:

  • Biodegradability describes a material that can be broken down by microbial activity (bacteria and/or fungi) into carbon dioxide, water vapor, and microbial biomass
  • Compostable describes a material that disintegrates and biodegrades under specific conditions and time-frames without releasing any harmful chemicals, toxic components, or heavy metals

In other words, compostable is a subset of biodegradable. All compostable materials are biodegradable but not all biodegradable materials are compostable.

Source: Closed Loop Partners‌ ‌

Any bioplastic that fits within the compostable sphere must meet a stringent and higher environmental bar. Certified industrially compostable materials must meet 4 requirements:

  1. Disintegrate into fragments that are no longer visible
  2. Biodegrade and convert into carbon dioxide, water vapor, and biomass
  3. Leave no trace of heavy metals or fluorinated chemicals
  4. May not contain byproducts with harmful effects on plants

Despite biodegradability’s benefits, biodegradable materials will not necessarily biodegrade of their own accord in unmanaged environments such as landfills. Microbes are hungriest when necessary conditions on temperature, moisture, and oxygenation levels are met. If not, biodegradable materials can actually persist in the environment for long periods of time or worse, disintegrate into smaller and smaller microplastics invisible to the human eye. For this and a host of other environmental and human health reasons, no plastic or packaging should end up in landfills or our rivers and oceans. Instead, materials should be circulated optimally in controlled conditions by either being recyclable or compostable. This is exactly why entire states (e.g., California) are mandating their entire packaging portfolios be either recyclable or compostable by 2030.

End of life for bio-PET vs. PHA and wtf is PEF?

In the upper left quadrant of our definitional 2x2, the biobased but chemically identical plastics (e.g., bio-PET) can be recycled alongside existing virgin (fossil fuel-based) plastics.

As consumers lean green, the market has responded with an outsized proliferation of new bioplastic materials, each with their own combination of feedstocks and processing requirements. But new materials don't necessarily solve plastic’s dirty challenges without considering the restrictions of the entire system of recycling and compost facility partners. Said bluntly, biodegradable is moot if the material isn’t managed under the right end of life conditions.

We’ve been confused by the labeling on many a recent water bottle made from new “recyclable biodegradable” bioplastics. Natureworks’ PLA brand Ingeo and PEF (yes, with an “F”?) being prime examples. PEF is a PET look-a-like, but with similar - and in some cases, better - physical performance properties like barriers. Avantium, who produces PEF, claims that their “plant plastic would decompose in one year using a composter, and a few years longer if left in normal outdoor conditions. But ideally, it should be recycled.”

Your spidey senses should be tingling. There’s a few things off here. First, composting is defined by the specific timelines of the process: certified compostable material needs to convert 90% of the organic carbon in a package to carbon dioxide within 180 days - not the year-long timeline cited. Second, decomposing over a few years if “left in normal outdoor conditions” frankly sounds a lot like littering, and early reporting on the material indicates that PEF is not biodegradable. Cue a host of lawsuits and concern that new bioplastics’ misuse of the term “biodegradable” could be more of a marketing ploy than physical reality. Seriously, a number of states have outlawed the term biodegradable in on-package labeling.

The reason that PEF, like many new materials, are not widely recycled despite being technically recyclable has less to do with the push of new chemistries and more to do with the pull (or lack thereof) from the economics of recyclers and composters. Three key factors determine the price of recyclers’ and composters’ end products. (Remember: these are commodity businesses that sell bales of recycled material and pounds of compost.)

  1. Physical capabilities: First, material recovery facilities (MRF, pronounced “murf”) where sortation of recyclables happens may not have the sortation capabilities to physically identify the new material and pick it off the conveyor belt. For example, Ingeo (PLA) requires near infrared (NIR) sortation sensors, and not all MRFs have these. MRFs may not sort out a material because it’s also physically indistinguishable from other plastics, or because the new material creates a new format of packaging the MRF isn’t used to (think: a small makeup container like a lipstick tube).
  2. Volume: Second, the initial volumes of the new material may be too low to incent a MRF to spend enough (read: time, labor, capex) to positively sort out these materials. If there isn’t enough volume, it’s a cost for a MRF to store that bale (even if they can sort it), and too low volumes make it hard for them to find end market buyers. Put simply: there is not enough resale value to make sorting out this material worth it.
  3. Contamination: The wrong material in the wrong place creates costs for recyclers and composters alike. Material that ends up in the wrong stream (e.g., a compostable plastic in the recycling system or a clear recyclable plastic in a composters heap) damages the purity of what should be recyclable or compostable and decreases the purity of recyclers’ and composters’ salable end product, and price. Anything that can’t be recycled or composted has to be sent to landfill for $50/ton!

Bio vs dino: bioplastics’ challenges in a fossil-dominated market

First, cost. The petrochemical industry has optimized the ingestion of fossil-based feedstocks cheaply over centuries, and starting over with net new biobased feedstocks and biodegradable processes that are better and cheaper out of the gates is no easy feat. Consider cost across the lifecycle:

Feedstock: Varies by type (sugar, wood, agriculture residues, even human waste!) and volume, though feedstocks are generally the largest contributor to cost - and also differentiate price to the greatest degree

Opex: Varies a lot by process and feedstock types, particularly for bioplastics

Capex: Generally decreases with scale, but takes (expensive) time and infrastructure dollars

Biobased feedstock costs compared to oil (source: Origin Materials) 

Second, scale limitations via technology scaling and feedstock scaling. Particularly for biobased plastics, the lab → pilot → demonstration → commercial scale-up challenges are particularly, well, challenging given constraints to sourcing massive quantities of waste biomass. Biomass is a hot commodity with competing existing demand from fuels and even carbon removal. A large amount of US corn and Brazilian sugar goes to biofuel production. Biobased feedstocks are therefore at the whim of commodity prices and system-wide land use decisions.

Third, convincing stakeholders. Most everybody hates change, including industrial partners who are skeptical of novel bioplastic innovations. This leads to a few key hurdles that innovators need to overcome:

  1. Prove cost-effective biobased feedstock collection, at volume
  2. Convince a packaging manufacturer to test small volume runs on their existing equipment (otherwise build out a new processing facility!) to prove processing performance
  3. Ensure that the material performs well for the converter who extrudes the new material into its final packaging format
  4. Generate demand from brands to request/ buy this new material from their suppliers. The brands then put the material through the ultimate test - imagine containing a fizzy soda through a hot distribution center and on a refrigerated shelf for 6 months or more.

After satisfying cost, scalability, and performance, new materials innovators must convince and cajole a bevy of stakeholders throughout the relatively old-school plastics value chain that’s rife with centralized infrastructure and industrial incumbents. Regardless of innovators’ potential, momentum favors the incumbents and it can take an entire decade, if not longer, for new bioplastics to proliferate through the value chain.

Key Takeaways

  • Don’t drown in the greenwashing alphabet soup. Stay afloat through the intentional obfuscation and remember that:
  1. Biobased and biodegradable are not mutually exclusive
  2. Materials should be designed to be either recyclable or compostable at end of life
  3. Not all plastics are created equal, and the impact potential of new materials should account for end of life management, not just hypothetical performance
  • Mind the biobased feedstock limits. The age-old question surrounding waste biomass is when does the supply party stop? Today’s challenges are less about the total pool of feedstock supply vs. the lack of centralization and efficient distribution from nascent global biomass supply chains.
  • LCA 123s. Bioplastic lifecycle sustainability claims must account for differences between virgin and waste feedstocks, substitutes and replacements, as well as second-order impacts to land use, energy consumption, and short vs. long carbon cycles. Get the calculator handy, this math isn’t simple and the devil is in the details.
  • Biobased is not 100%. Most bioplastics aren’t made from 100% renewable materials but rather are mixed with conventional plastics to retain unit economics and/ or performance. Naturally, the petroleum blending percentage significantly skews “bioplastics” decarbonization impact.
  • Biobased is not all. When it comes to decarbonizing plastics’ total dirty emissions, bioplastics are just one lever within the broader switchboard: feedstock changes, power/ heating using renewables or hydrogen, decarbonizing distribution, and ensuring a circular end of life.
  • Testing, testing vertical integration. Smart innovators are testing and choosing how far up/ down the plastic value stack to integrate. In the upstream case, operators like Fullcycle are directly owning their feedstock supply to shore up risks from low, disparate volumes. Others are headed downstream, designing entirely new polymers and bioplastics to get closer to the end consumers’ demand for sustainability alternatives. Innovators may go even further to win the hearts and minds of the end retailers who have the procurement power to influence suppliers up the stack.

Life in bioplastic, it’s fantastic with Hannah Friedman and Keeton Ross’s imagination and creation of this feature. Let’s go party together on the next CTVC plastics installment. What’s your level of interest in a deep dive into the recycling value chain after a recyclable material (like PET, HDPE, paper, glass or aluminum) comes off of the curb? You want to go for a ride? We are just getting started.

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