Note: This is the first article of a three-part series covering bioplastics (1) trends, (2) material/process advances and (3) applications.

Interest in bio-based plastics is closely connected to the price of oil and is a key driver for demand of bio-based polymers. Government legislation and incentives are also strong drivers, and many companies have mandated increased use of "renewably sourced" materials in their products.

Last but not least, major companies continue to develop their sustainable brand image aimed at the new "circular economy" consumers (i.e., design in bioplastics, product reuse, material recyclability, greenhouse gas footprint reduction) versus the current linear economy (i.e., make, use, discard). Bioplastics currently depend on less than 0.01 percent of the total global agricultural area.

There is high volatility of oil prices currently. During periods of tight balance between oil supply and demand in the world market, any incident or crisis can send oil prices soaring or plummeting.

Inflation-adjusted oil prices reached an all-time low in 1998 at $17.10 per barrel — lower than the price in 1946. And then just 10 years later, oil prices were at the all-time high for crude oil at $135.04 per barrel — above the 1979-80 price peak of $115.89 per barrel in real inflation-adjusted terms. Brent crude is priced at $44.63 per barrel today.

Competing with fossil fuel is one of the main challenges for bioplastics, which can cost anywhere from 10 percent to 100 percent more than traditional plastics, depending on the grade and type of chemical compound being produced.

Major chemical companies are making significant investments in new plants and technologies to produce plastics from annually renewable sources, not from petrochemicals. Some are producing conventional plastics from unconventional feedstocks like ethanol fermented from sugar cane, or plan to use CO2 and CO directly. Others are developing new monomers using other fermentation chemistries.

The word bioplastics is no longer limited to biodegradable or compostable plastics made from natural materials such as corn or starch. Bioplastics are also being applied to petroleum-based plastics that are degradable, natural-based plastics that are not necessarily biodegradable, and plastics that contain both petroleum-based and plant-based materials that could biodegrade or not.

The classification of bioplastics is being redefined as:

  • Bio-based, or biosourced, plastics with the major focus being the material's "origin of carbon building blocks" and not by where it goes at the end of product life.
  • Biodegradable plastics with the focus on the materials' "end of life disposal."

European Bioplastics
Fossil fuel-based materials (left) versus bioplastics standardization (right, center).

Bio-based material is not necessarily biodegradable, nor is biodegradable material necessarily bio-based. Ethylene from ethanol is identical to ethylene from naphtha, and plastics made from bio-ethylene are indistinguishable from petrol-derived resins.

Many assume it is the nature of all petrochemical-based polymers to not be biodegradable simply because they are made from petroleum. This is not true. Ecoflex is an example of a petrol-based plastic that is biodegradable. These BASF products will readily biodegrade in commercial compost systems.

Breakdown is so complete that BASF refers to it as a "fertilizer." Ecoflex is fully certified as biodegradable and compostable within approximately 180 days maximum ― in the U.S. by certification of the Biodegradable Products Institute (ASTM D 6400); in Europe under the European Standard EN 13432; and in Japan by the GreenPla Standard.

Bio-based content is the weight fraction of the total organic carbon in the material that is bio-based. Currently, there is no official minimum bio-based material required to call a plastic bio-based. The U.S. Department of Agriculture (USDA) sets a minimum bio-based content on a product-by-product basis for its BioPreferred federal procurement program. For example, plastic cutlery is set at 33 percent.

Global bioplastics production capacity will grow 400 percent from 2012 to 2017. The composition of bioplastics production capacity is expected to change significantly from 53 percent bio-based/nonbiodegradable in 2015 to 80 percent by 2017.

Leading the field is partially bio-based polyethylene terephthalate (PET), which accounts for approximately 39 percent of the global bioplastics production capacity. Biodegradable plastics including polylactic acid (PLA), starch-blends and biodegradable polyesters are also demonstrating impressive growth rates.

While Europe is the world's largest market for bioplastics, production capacity is growing most rapidly in Asia and South America. Asia and South America are projected to account for 75 percent of global bioplastics production capacity by 2017.

European Bioplastics
Global bioplastics production capacity forecast.

While bioplastics are being embraced, a number of issues continue to pose challenges:

Oil price volatility: With a tight balance between oil supply and demand in the world market, any incident or crisis can send oil prices soaring or plummeting.

Higher prices compared with traditional plastics: Competing with low-cost fossil fuel is one of the main challenges for bioplastics, which can cost anywhere from 10 percent to 100 percent more than traditional plastics, depending on the grade and type of chemical compound being produced. Braskem's green polyethylene (PE) carries a price premium as high as 66 percent.

Labeling confusion: Consumers are still trying to grasp recycling basics. When biodegradable and compostable plastics are added to the mix, it just adds to the confusion. Compounding the confusion is a proliferation of ecolabeling in the marketplace. To reduce the bioplastics labeling uncertainty, bioplastics manufacturers are actively seeking stricter regulation of existing certification processes. To address some of the confusion, an ASTM working group composed of interested plastics producers and stakeholders is re-evaluating the Resin Identification Coding system to better deal with PLA and multilayer plastic materials for recycling requirements.

Recyclability: There are also growing concerns regarding contamination of conventional plastic recycling streams by biopolymers with U.S. composters calling for a more universally recognizable compostability label to prevent such contamination problems.

Availability of industrial composting facilities: Bioplastics such as PLA are only compostable at temperatures/operating conditions achieved in industrial composting facilities, and many communities do not have access to industrial composting operations.

Skepticism on functional abilities and environmental claims: Greenwashing tactics and overemphasis on environmental benefits are prompting consumer skepticism.

Over-reliance on food crops: We must move to lignocellulosic biomass as rapidly as possible. One example is a durable new high-performance bioplastic developed by electronics giant NEC. Based on plant stems and nut shells abundant nonedible resources discarded as byproducts of agricultural processing this new bioplastic will have little impact on food crop production. China, a net importer of carbohydrates, is seeking to limit crops that can be used to make chemical intermediates to not compete with food production.