Wednesday, May 18, 2011

Meandering Thoughts on Plastic Wrap

I use plastic wrap for my sandwich that I take to work for lunch. You’d think after all these years that the manufacturers would have figured out how to dispense this product without having it become hopelessly stuck together on its roll in the box. Much less get it to tear evenly once you’ve managed to get it unrolled. So I started to wonder: Just how long HAVE they had to get this under control?

I searched online and read that Saran polyvinylidene chloride or Saran resins and films have been wrapping products for more than 50 years. Saran works by polymerizing vinylide chloride with monomers such as acrylic esters and unsaturated carboxyl groups, forming long chains of vinylide chloride–this copolymerization produces a film with molecules bound so tightly together that very little gas or water can get through.

Got all that? I started to fade a bit at “copolymerization”. I was an art major in college, and the only science classes I took were under duress. In a high school science class I once answered an involved test question about the differences between plant and animal life with the smart-ass answer of “One has a root, the other a foot”. That answer got a shocked look and a stifled laugh from the girl sitting next to me, and my teacher was only mildly amused.

As often seems to happen, the discovery of plastic wrap came about inadvertently. In 1933, Ralph Wiley, a college student who cleaned glassware in a Dow Chemical lab, accidentally discovered polyvinylidene chloride–only because he couldn’t wash it out of the beakers he was trying to scrub clean.

Dow researchers managed to make Ralph's discovery into a greasy, dark green film, which Dow trade named "Saran". Why “Saran”? According to someone on the web, “The Turkish word 'sarmak' mean 'to wrap'. 'Saran' is the present participle of 'sarmak'. In other words, saran = wrapping in Turkish.” Someone at Dow was a Turkish scholar? Another explanation for the name is that Wiley's two daughters were named Sara and Ann. Hence the polymer he created was named "Saran." Take your pick.

However the name came about, the product was only a middling success initially. The military sprayed Saran on fighter planes to guard against salty sea spray, and carmakers used it on upholstery to protect the seats against the elements (and the mishaps of small children). Dow continued to refine Saran, eliminating its original green hue, and ridding it of its offensive odor. Hey, it’s always been hard to market products with offensive odor. Even in the name of progress in the “go-go” post World War II era, when an optimistic America believed that science could solve any problem, deal with any issue.

Dow finally got their Saran film out to the consumer in the form of Saran Wrap, the first cling wrap designed first for commercial use (1949) and then into households in 1953. Over the years, it’s been discovered that the plasticizers in PVC can migrate to some foods such as cheese, fatty fish and even meat. It's caused enough concern that several countries around the world have banned it. Today, most plastic wrap for home use no longer contains PVC’s; instead they are made of low density polyethylene (LDPE). It doesn’t cling quite as well, but it’s probably better for your leftovers.

I visited the Saran Wrap site and learned that I am not alone in my mishaps with plastic wrap. Here are a couple of gripes consumers have posted:

“What can I do to prevent losing the end of my Saran Plastic Wrap and keep it from tearing when I unroll it?”

“My Saran Wrap keeps popping out of the box when I use it. How can I prevent this?”

Not to mention the numerous complaints about the wrap not sticking, or sticking too much–generally to itself. On the roll. Seems there are a lot of people who are plastic wrap challenged.

 I discovered there’ are several alternative uses for plastic wrap aside from the intended. To wit: prevent ice crystals from forming on ice cream in the freezer. Completely wrap the ice cream container in plastic wrap before returning it to the freezer. Oh, right. And while you’re at it, wrap the dog so you don’t have to vacuum up pet hair ever again...

I did like this one: Clean the top of your refrigerator for the last time! Clean it, then cover it with overlapping layers of plastic wrap. When it gets dirty again, merely pull off the wrap and put down a new layer. For those of you that think it would be tacky and ugly to cover the top of your refrigerator in plastic wrap, I’ve got to ask you–how often do you look up there? It’s already tacky and ugly.

So now I know more about plastic wrap than I will ever need to know in my lifetime. And though I have been told that with knowledge comes power, I know that in my daily battle with the wrap, the wrap shall triumph more than I. And probably draw blood, too, just to show it can.

1 comment:

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