I’ve been reading quite a bit about some of the environmental problems that we face with microplastics and PFAs (forever chemicals), and it got me thinking about composites as a source of at least part of this problem. That is because the resins or glues that hold the fibers together are all plastics of some sort, and some of the chemistry to make them is quite toxic. It is also because a big part of the microplastics problem is plastic microfibers.
This was actually inspired by my wife who put me on to some articles about the microplastics pollution problem that had come up in her news feed, as well as her asking me about microplastics and PFAs in composites.
So, I took a look into this and there is a lot here to talk about, so I decided that for the next few weeks to maybe a few months as I dig more into this, I would talk about this in these newsletters. Over the last three years or so I have covered many topics in composites, and for about the last 6-9 months these have been about sustainability and this seemed to me to be a natural transition for this newsletter.
This week I want to lay out the landscape and the potential sources from the composites industry for introducing these pollutants into our atmosphere and water supply, as well as the impacts on local and global ecosystems. And since I’m pretty much a cradle to grave sort, I need in this week’s post to lay the foundation for what I am going to write about in the coming weeks to months.
Since we need to start at the beginning, I am going to have to start with the initial sources of toxic chemistries and microplastics from the precursors to all of the fibers and resins that make up current composite materials. I also need to assure everyone that this is really not a doom and gloom story, nor will it be slanted in any direction. Instead what my intent here is to provide what the current state of the art is in the composites industry; what the industry looked like in the past; what the potential sources of toxic chemistries are both in the manufacture of composite parts as well as the used up composite parts (like wind turbine blades); where these chemistries and microplastics can infiltrate the air, water, or soil; and what the industry both is doing about this now as well as what is possible to eliminate this source of pollution. So, like most things, this is a bad news, good news story and that is what you will see unfold over the course of the next several weeks.
With this post, what I need to do then is to lay the groundwork for the next few weeks to months by giving everyone a very high level listing of the potential sources of these pollutants from each step in what the industry calls the “value chain” of composites. So, let’s start with the precursors and how things like epoxy, polyester, vinyl ester, phenolic, etc. resins are made and also how carbon fibers, other organic fibers, things like Spectra and Dyneema are made. This of course starts with crude oil and the refinement of that into the organic compounds like ethylene, acrylonitrile, bisphenol-A, propylene, etc. Most of the creation of these compounds has been covered by anyone working in the refinery business so there is no need to cover them here.
So, we will start with these raw materials once they are provided to the resin and fiber manufacturers and work from there. There are of course also things like solvents, release agents for molds, microplastics from the vacuum bags, etc. that also need to be talked about so that everyone understands the sources of the chemistries and microplastics that are potentially harmful to the environment.
The actual manufacturing of the fibers (strings) and resins (glues) would of necessity come next, so I will talk about how the fiber and resins are made, what toxic chemistries (lots of ammonia, some cyanides, strong acids, and strong bases) are involved in the conversion of the raw organics into useful composite resins and useful fiber precursors. Also involved in this discussion will need to be what heat source is used currently in the production of these strings and glues, and what potential pollutants result from that.
Once the fiber and resins are manufactured, they are made into parts, and so the next topic is what effluents the part fabrication process produces and also what the potential for the waste from the part manufacturing process really is. There is always scrap material left over that needs to be disposed of that can have potentially toxic chemistries, especially from uncured resins. There are also the other organics and things like sanding dust that contain microplastics in all sorts of forms that eventually end up either in landfills, the air, or in the local rivers and streams.
During the time that the composite is in use, in general the resin systems are very slowly degrading. This is because we use composites largely because of their resistance to rapid degradation in the environment like is the case with most metals. Aircraft and watercraft are the two largest sources of this, since resin systems degrade from UV exposure and also from immersion in seawater. Every boat owner knows that a coating of UV protectant wax is required on the topsides of their boat to keep the finish nice and shiny rather than dull and oxidized. And the aircraft industry is constantly inspecting and repainting the exterior surface of aircraft to reduce the exposure to UV since it is so much higher intensity at 35,000 feet than it is on the surface. This maintenance and the materials used to maintain these composite surfaces is also a source of pollution.
Then, I need to talk about what we need to do with composites that have reached the end of their useful life. And while I understand that I have talked about this quite a bit in this newsletter, it is time to change the focus a bit to investigate what happens when used wind turbine blades are just piled up and left to in a field exposed to the elements. This is also true of abandoned boats along our lakes and seashores. What is the potential for the rotting fiberglass composites to release toxic chemistries into the soils and eventually streams, lakes, and the ocean. And, what happens as the boat or wind turbine blade eventually ends up a pile of junk that has large quantities of little broken fibers that can become airborne or waterborne and end up being microplastic and microfiber pollutants.
Finally, I need to bring all of this back home and talk about what the industry has already cleaned up, what they are doing now to mitigate this source of pollution, and what needs to be done in the future. A good example of this is the change made in the boat building industry from the heyday of the 1970’s when there were all manner of sailboat manufacturers in Southern California, harbors in the Northeast US and Great Lakes, and several coastal cities in Europe. The resin of choice back then was isophthalic polyester which is cured in an abundance of styrene to make the backbone of the resin. Workers used to build these hulls outside without any protective gear, where they would roll on the uncured resin down inside the mold of a 42 foot sailboat (think Westsail 42) and breathe in all of the styrene fumes coming off the resin. A lot of those guys ended up with lung cancer that killed them at an early age. Since the inception of the EPA and the creation of rules about styrene emissions, that process has become very tightly controlled, is always done indoors with low VOC resins, with workers in complete protective gear, and a positive ventilation system with very tight filtration of the air before it is exhausted into the atmosphere.
That is an introduction into what I am going to write about for the next few weeks to months. My intent here is to provide not only my readers, but also those that are in the composites industry a roadmap of sorts for things that can be done today to begin to modify their processes to slowly eliminate the toxics and microplastics from their part of the industry. Again, this is a start with little things that can be done right away and put together a plan for getting to a future where the composites industry no longer contributes either to the microplastic problem nor to the forever chemicals (PFAs) problem that is looming in front of us.
That’s about it for this week. Please remember that this is part one or alternatively the introduction to a multi-part series on this topic. It follows directly from the subject of my second book on composites sustainability, so I’m treating this as a natural progression of this newsletter.
As always, I hope everyone that reads these posts enjoys them as much as I enjoy writing them. I will post this first on my website – www.nedpatton.com – as then on LinkedIn. And if anyone wants to provide comments to this, I welcome them with open arms. Comments, criticisms, etc. are all quite welcome. I really do want to engage in a conversation with all of you about composites because we can learn so much from each other as long as we share our own perspectives.
My second book is now in the hands of my publisher, with just one thing left for me to do. Most of you know that it is about what I have been writing in these newsletters for the last 6 months or so – sustainability of composites and a path to the future that does not include using fossil fuels for either the raw materials or the process energy to make composites. The title of the book, at least for now, is “Close the Circle, A Roadmap to Composite Materials Sustainability.” It truly is a roadmap which I hope that at least at some level the industry will follow. Only time will tell.
Finally, I still need to plug my first book, so here’s the plug. The book pretty much covers the watershed in composites, starting with a brief history of composites, then introducing the Periodic Table and why Carbon is such an important and interesting element. The book was published and made available last August and is available both on Amazon and from McFarland Books – my publisher. However, the best place to get one is to go to my website and buy one. I will send you a signed copy for the same price you would get charged on Amazon for an unsigned one, except that I have to charge for shipping. Anyway, here’s the link to get your signed copy: https://www.nedpatton.com/product-page/the-string-and-glue-of-our-world-signed-copy. And as usual, here’s a picture of the book.
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