Plastics – part 1

28 04 2010

Philosopher George Carlin once said,   “Man is only here to give the planet something it didn’t have:   Plastic.”

And man has done well:  plastic is ubiquitous in our world today and the numbers are growing.   We produce 20 times more plastic today than we did 50 years ago.

The production and use of plastics has a range of environmental impacts. Plastics production requires significant quantities of resources:  it uses land and water, but the primary resource is fossil fuels, both as a raw material and to deliver energy for the manufacturing process. It is estimated that 8% of the world’s annual oil production is used as either feedstock or energy for production of plastics.

Plastics production also involves the use of potentially harmful chemicals, which include cadmium, lead, PVC, and other pollutants which are added as stabilizers, plasticizers or colorants. Many of these have not undergone environmental risk assessment and their impact on human health and the environment is currently uncertain.  Finally, plastics manufacture  produces waste and emissions. In the U.S., fourteen percent of airborne toxic emissions come from plastics production.  The average plastics plant can discharge as much as 500 gallons of  wastewater per minute – water contaminated with process chemicals.  (The overall environmental impact varies according to the type of plastic and the production method employed.)

Every second, 200 plastic bottles made of virgin, non-renewable resources are land-filled – and every hour another 2.5 million bottles are thrown away.  And though I can’t get a definitive answer about whether the plastics decompose (because although they don’t biodegrade they do photodegrade – when exposed to UV radiation, over time they break down into smaller and smaller bits, leaching their chemical components), most sources, if they do accept that plastic can degrade, admit that nobody knows how long it really takes because most plastics have only been around for 50 years or so  –  but estimates range into the thousands of years.   (To read how scientists make estimates for plastic decomposition rates, click here. )

How do we cope with this plastic onslaught?

Recycling is the most widely recognized concept in solid waste management – and the environmental benefits of recycling plastic are touted elsewhere.  I’ll just give you the highlights here:

  • It reduces the amount of garbage we send to landfills:  Although plastic accounts for only 8% of the waste by weight, they occupy about 20% of the volume in a landfill due to their low bulk density.
  • It conserves energy:  recycling 1 pound of PET conserves 12,000 BTUs of heat energy; and the production of recycled PET uses 1/3 less energy than is needed to produce virgin PET.
  • It reduces greenhouse gas emissions.
  • It helps conserve natural resources.

But it should be remembered that some items are much better candidates for recycling than others.  Aluminum recycling, for example, uses 95% less energy than producing aluminum from bauxite ore, and aluminum cans can be recycled into new aluminum cans.  There is no limit to the amount of times an aluminum container can be recycled. The PET bottle, which is used for everything from water to wine,  was patented in 1973 – that’s only 27 years ago!  Prior to that most bottles were of glass.  Glass, like aluminum,  is infinitely recyclable.  As late as 1947, virtually 100% of all beverage bottles were returnable; and states with bottle deposit laws have 35 – 40% less litter by volume.  I found this image while looking for Earth Day anniversary images, and think it’s a great example of how corporations will slant anything to their purposes.  (Please note that the company in question is Coca Cola – I’ll have a lot to say about Coke’s recycling efforts in 2010 in upcoming blog posts):

There are different costs and benefits for other recyclable items: plastic, paper, electronics, motor oil… They each have their own individual problems.

With reference to the textile industry, 60% of all the virgin polyethelene terephthalate (PET) produced globally is used to make fibers, while only 30% goes into bottle production.  As I explained in a previous blog,  the textile industry has adopted recycled polyester as the fiber of choice to promote its green agenda.   What I want to do is expose this choice for what it is: a self-serving attempt to convince the public that a choice of a recycled polyester fabric is actually a good eco choice – when the reality is that this is another case of expediency and greed over any authentic attempts to find a sustainable solution.  My biggest complaint with the industry’s position is that there is no attempt made to address the question of water treatment or of chemical use during dyeing and processing of the fibers.

So to begin, let’s look at what plastic recycling means, since there are many misconceptions about recycling plastic – especially plastic bottles from which (some) recycled polyester yarns are made.

In 1970, at the time of the first Earth Day, Gary Anderson won a contest sponsored by Container Corporation of America to present a design which symbolizes the recycling process.  His winning design  was a three-chasing-arrows Mobius loop, with the arrows twisting and turning among themselves.   Because of the symbol’s simplicity and clarity it became widely used worldwide and is a symbol now recognized  by almost everyone.  Today almost all plastic containers have the “chasing arrows” symbol.  We’re bombarded with that symbol – any manufacturer worth his salt slaps it on their products.

But the symbol itself is meaningless.  This symbol is not a government mandated code, and does not imply any particular type or amount of recycled content.  Many people think that the “chasing arrows” symbol means the plastic can be recycled – and that too is untrue.

The only useful information in the “chasing arrows” symbol is the number inside the arrows, which indicates the general class of resin used to make the container. There are thousands of types of plastic used for consumer packaging today. In 1988, the Society of the Plastics Industry devised a numbering system  to aid in sorting plastics for recycling, because in order to be recycled,  each plastic container must be separated by type before it can be used again to make a new product. Of the seven types, only two kinds, polyethelene terephthalate (PET), known as #1, and High Density Polyethelyne (HDPE) – or #2 –  are typically collected and reprocessed.   Some of these resins are not yet recyclable at all (such as #6 or 7), or they’re recyclable only rarely.

In addition, a resin code might indeed indicate #1 (PET) for example, but depending on the use (yogurt cup vs. soda bottle) it will contain different dyes, plasticizers, UV inhibitors, softeners, or other chemicals.
This mix of additives changes the properties of the plastic, so not all #1 resins can be melted together – further complicating the process.  Here’s a list of the seven resin codes and some of the concerns associated with each:

Consumers see the symbol and  – thinking it means the plastic can be recycled – drop bottles into recycling bins, feeling they’ve “done their part” and that the used bottle is now part of the infinite loop, becoming a new and valued product.  But does the bottle actually get “recycled”, returning to a high value product, staying out of the garbage dump?

Well, uh, . . .  not really.  Collecting plastic containers in a recycling bin fosters the belief that, like aluminum and glass, the recovered material is converted into new containers.  In fact, none of the recovered plastic containers are being made into containers again, but rather into new secondary products, like textiles, parking lot bumpers, or plastic lumber – all unrecyclable products.  “Recycled’ in this case merely means “collected.”

A bottle can become a fabric, but a fabric can’t become a bottle – or even another fabric, but we’ll get to that later.  There are far too few exceptions to this rule.

Plastic has what’s called a “heat history”: each time it gets recycled the polymer chains break down, weakening the plastic and making it less suitable for high end use.  PET degrades after about 5 melt cycles.  This phenomenon, known in the industry as “cascading” or “downcycling,” has a troubling consequence.    It means that all plastic – including the tiny proportion that finds its way into another bottle – “will eventually end up in the landfill,” said Jerry Powell, editor of Plastics Recycling Update.

The technology exists to recycle most kinds of plastic, but a lack of infrastructure prevents all but the most widespread kinds of plastic from being recycled.  Collection is expensive because plastic bottles are light yet bulky, making it hard to efficiently gather significant amounts of matching plastic.  For recycling to work, communities must be able to cost effectively collect and sort plastic, and businesses must be willing to accept the material for processing. So no matter whether a particular plastic is in a form which allows it to be melted and reused, something is only recyclable if there is a company out there who is willing to use it to make a new product. If there is no one who will accept the material and make a new product out of it, then it is not recyclable.

Only a few kinds of plastic have the supply and market conditions that make recycling feasible. With plastics in particular, how the plastic particles are put together (molded or extruded) changes their chemical make up and make them non recyclable in certain applications. Some bottles make it to a recycler, who must scramble to find a buyer.  The recycler  often ends up selling the bottles at a loss to an entrepreneur who makes carpeting or traffic strips – anything but new bottles.

Recycling reduces the ecological impact of plastic, but it remains more complicated, more expensive and less effective than other parts of the recycling industry. No matter how many chasing arrows are printed on plastic products, it doesn’t change the fact that plastic is largely a throwaway material.

Next week:   what is the plastic industry doing to create a stronger recycling market for its product?

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Is recycled polyester fabric RECYCLABLE?

11 11 2009

Is it true, as one of the leading fabric distributors says of its “green” fabrics made of recycled polyester, that after “years of enjoyable use, these fabrics are recyclable?”   Does buying that fabric really help reduce our dependence on a non renewable resource  and lessen the burden that plastic is inflicting on our environment?

I’d like to show you how this is a misleading statement.  It’s a bit complicated, but stick with me because the industry is depending on your confusion.  If you know what they’re really foisting on us, you might want to demand a better, cleaner, altogether different product!

Only recycle

But first I have to back up and point out that “recyclable” is one of those amorphous words that have no accepted definition.  We can “recycle” our fabrics by repurposing them, donating them, use them for quilting or in other ways…but somehow I think they really meant for us to believe that the plastic yarns could be recycled into new and equally beautiful new fabrics:  the ultimate “infinite closed loop”.

So, the first thing you must understand in order to grasp why this is a disingenuous statement is that there are two ways plastic can be recycled:  Mechanically and chemically.

Mechanical recycling is the kind that almost all recycling facilities use today. The first step in the process is to collect the plastics and then separate all the different types of plastic (“feedstock”) to avoid contamination – different plastics have different melting points and other characteristics; if they were thrown into the pot together the result would be an unuseable mess.  (Remember this fact: the recycling of plastics must always be done with like resins – this will come up later in textiles.)   So after separation, each type is melted down and then  re-formed into small “chips” or “pellets”.  These chips are what a widget manufacturer buys from the recycling facility to make its product – or what a yarn manufacturer buys to make the yarns to weave into cloth.

Common misconception about recycling:  you might think that if you throw your used drink bottle into the recycling container that it will be recycled into another new drink container.  Nope.  The melted resin contains contaminants and would not meet food grade requirements, so it is instead destined to go into a secondary product, such as yarn for the fabric we started talking about at the beginning of this blog.  A better name for the “recycling container” would be “collection container”.

recycl poly From  Help me! – the earth by Memo

A fabric made of “recycled material” has a certain percentage of polyester which comes from these chips that the recycling facility has manufactured.  Using these chips has several issues which are exclusive to the textile industry:

  • The base color of the recycled polyester chips vary from white to creamy yellow, making color consistency difficult to achieve, particularly for the pale shades.  Some dyers find it hard to get a white, so they’re using chlorine-based bleaches to whiten the base.
  • Inconsistency of dye uptake makes it difficult to get good batch-to-batch color consistency and this can lead to high levels of re-dyeing, another very high energy process.  Re-dyeing contributes to high levels of water, energy and chemical use.
  • Unsubstantiated reports claim that some recycled yarns take almost 30% more dye to achieve the same depth of shade as equivalent virgin polyesters.[1]
  • Another consideration is the introduction of PVC into the polymer from bottle labels and wrappers.
  • Many yarns made from recycled polyester are used in forgiving constructions such as polar fleece, where the construction of the fabric hides slight yarn variations.  For fabrics such as satins, there are concerns over streaks and stripes.

Most of the plastics in use today can be recycled but, because mechanical recycling produces a less stable polymer, the products which can be made from this recycled plastic are of “less value” than the original.  The products made from the “chips” must be a bit forgiving, such as carpet, plastic lumber, roadside curbs, truck cargo liners, waste receptacles (you get the idea).  William McDonough calls this “downcycling”.  No matter how many smiling people you see throwing their bottles into a recycling container and “preventing the plastic from entering our waste stream” as the media likes to put it – the reality is that the recycling can only be done mechanically a few times before the polymers break down and the plastic is no longer useful or useable – every time plastic is melted down, its molecular composition changes, its quality degrades, and the range of its usefulness shrinks.   So after going from a virgin PET bottle, to carpet fibers, to plastic lumber, to a speed bump – that’s when it enters our waste stream.  So recycling plastic doesn’t prevent this occurrence – it just postpones it.  Read more about “the seduction of plastic”  here.

To add insult to injury, if you had bought the fabric mentioned above and hoped the fabric would be recyclable as claimed:  probably not gonna happen, because remember how the recycling facility had to separate bottles to make sure each resin was melted with similar types?  Think of the fabric as similar to bottles with different plastic resins:  many fabrics are woven of different types of plastic (60% polyester, 40% nylon for example), or there is a chemical backing of some sort on the fabric.  These different chemicals, with different molecular weights, renders the fabric non-recyclable.  Period.

And even if the fabric we’re talking about is 100% polyester with NO chemical backings or finishes, there is a problem with recycling in the system itself.  Although bottles, tins and newspapers are now routinely collected for recycling, furniture and carpets still usually end up in landfill or incinerators, even if they have been designed to be recycled [2] because the fabric must be separated from other components if it’s part of an upholstered piece of furniture, for example.

Chemical recycling is the alternative technology and it does exist.  During chemical recycling, the materials are chemically dissolved into their precursor chemicals.  Polyester, for example, would be broken down into DMT (dimethyl terephthalate) and EG (ethylene glycol).  These chemicals are then purified and used to make new polyester fiber.  But the reality is that this is difficult and expensive to do.  Patagonia has made using recycled plastics a priority and gives a good overview of the process with interesting comments about the unique problems they’re encountering; read about it here.

Currently, fabrics identified as being “recyclable” really are not  – because the technology to recycle the fibers is either too expensive (chemical) or doesn’t exist (mechanical) and the infrastructure to collect the fabric is not in place.    Few manufacturers, such as Designtex (with their line of EL fabrics designed to be used without backings) and Victor Innovatex (who has pioneered EcoIntelligent™ polyester made without antimony),  have taken the time, effort and money needed to accelerate the adoption of sustainable practices in the industry so we can one day have synthetic fabrics that are not only recycled, but recyclable.

So when you buy a fabric made of recycled polyester, remember it’s at the end of its useful life as a plastic  – and you are contributing to our dependence on non renewable resources and to the overwhelming burden of non-degradeable plastic in our environment.

And lest you forget – or choose to ignore –  what that kind of degradation entails, Chris Jordan, a photographer based in Seattle, has documented it for us.   In a series of photographs entitled “Message from the Gyre”, he has documented what pieces of plastic are doing to albatross chicks on Midway Island.  In the interest of a faithful representation of their plight, not a single piece of plastic in any of the pictures was moved, placed or arranged in any way.  The images depict the actual stomach contents of baby birds in one of the world’s most remote marine sanctuaries, more than 2000 miles from the nearest continent.  See all the images and more of Chris Jordan’s work on his web site, www.chrisjordan.com

Chris-Jordan-Message-from-t_thumb


[1]“Reduce, re-use,re-dye?”,  Phil Patterson, Ecotextile News, August/September 2008

[2] “Taking Landfill out of the Loop”, Sarah Scott, Azure, 2006