In today’s world, a lot of us are concerned about the chemicals around us – in our cars, cell phones, clothing, food, and common household products. Some of our concern is due to our own observation, such as unnaturally and incredibly long shelf life in foods (hello, ramen noodles), but some concern arises from marketing and public safety messages, right? I mean, who wants to disinfect their kitchen floor before their child crawls across it by using cleaners that contain formaldehyde? At the same time, (again through both marketing and public announcements) certain “good chemicals” are touted as essential for a healthy lifestyle.
At Polymer Solutions Incorporated, we understand that everything can be broken down into the various molecules which comprise the whole. There are “good” and “bad” chemicals out there, but it’s all a matter of perspective. Most “good” chemicals can be harmful when too much is present (think of overdosing on a multivitamin, which is a significant risk of giving children adult-vitamins), and most “bad” chemicals are not considered toxic below certain levels (such as the cyanide naturally found in almonds).
Now that we’ve got you thinking about all the “chemicals” around you, bring to the front of your mind what you know about antioxidants. These are one of the “good” chemicals, right? Antioxidants are common in nuts, berries, beans and all sorts of healthy things. And how would you feel if I told you that water bottle you’ve been suspicious of lately has antioxidants in it, as well? Before you go bragging to your “only-drinks-from-glass-bottles-tree-hugger-neighbor” about your cancer-fighting water bottle, let’s talk about those antioxidants.
Antioxidants are, according to Merriam-Webster’s online dictionary, “a substance that inhibits oxidation or reactions promoted by oxygen, peroxides, or free radicals.” So, basically, antioxidants prevent unwanted oxidation reactions which can be harmful in your body. Likewise, antioxidants prevent the unwanted oxidation of polymer products which can lead to deterioration and failure. However, the antioxidants in your water bottle will not help you in your fight against biological oxidation. For one thing, our bodies are incredibly complex chemical environments, and hundreds, if not thousands of compounds may be present in the body which act as antioxidants.1 Being such a complex system, it is not easy to predict the ways which certain compounds will behave in the body, and many substances which may act as antioxidants in non-living systems may be metabolized in a manner which renders them ineffective, or even harmful, in the human body.
Antioxidants in the body are acquired through both production and consumption. A combination of a healthy lifestyle and a good diet typically provide all the antioxidants our bodies need.2 Despite what vitamin and nutrient company marketing offices have told us, scientific studies do not illustrate a great need to supplement our diets with boatloads of antioxidants. Most scientific studies show no clear benefit from antioxidant supplements beyond what is naturally consumed in a healthy diet and produced by the body. In fact, some studies even suggest that constantly overloading the body with too many antioxidants can have negative health effects. So what gives? It goes back to perspective. We can have too much of a good thing, and we can deal with little enough of a bad thing.1
Polymer systems, though often complex, are nowhere near the level of complexity of a living organism. The activity of certain compounds used as additives is, therefore, much easier to predict and study. Antioxidants are added to polymers to prevent the decomposition of the polymer, thereby causing failure. Since polymers are not biological systems, the sources of oxidation are much more limited and easier to combat. The breaking of polymer chains due to some stress (such as sunlight) is a common source of free radicals in polymeric systems. These free radicals react with other polymer chains to form more free radicals and cascade into the rapid deterioration of the polymer’s strength and performance. Antioxidants present in these systems intercede and slow or halt this process. Again, however, an overdose of the proper antioxidants can be harmful to these polymer systems and their intended uses by causing discoloration, a loss of efficiency, a change in adhesion properties and the ability of a material to be printed on, or the possibility of the additives leaching (you don’t want those specialized polymer antioxidants finding their way out of the plastic in that water bottle of yours).
Okay, so concentration is important. We don’t want too little or too much. We can have a Hershey Kiss, but we probably shouldn’t eat the 5-pound chocolate bar all by ourselves (even though dark chocolate is full of antioxidants). We want enough antioxidants in our beach chairs to keep us off the sand, but not so much that they coat our hands, and therefore our healthy antioxidant-packed blueberry snack, every time we sit in them. It’s important.
That’s why we’ve been making improvements to our Antioxidant Analysis methods here at PSI. We’ve improved our existing abilities to identify and quantify antioxidants by HPLC, and with our new LC-MS present and active, we will be all the more equipped to conquer any polymer-additive problems our clients may face.
This blog post was written by one of our amazing and brilliant scientists, Gavin Smith!