Tuesday, September 06, 2016

Curses! Environmental Stress Cracking

We've had a lot of aphids attacking plants in our garden this year. My usual approach is to use an insecticidal soap that I make by diluting down from a concentrate. "Normal" soap is the sodium salt of a fatty acid, while an insecticidal soap is just the potassium salt, which means the soap is relatively safe. It also works pretty well against the critters, and clean-up is easy. But they have gotten so out of hand that instead of making it up as needed, I made up a larger amount in a spray bottle and kept it in a cabinet.

Over the weekend, I knocked the bottle to the garage floor. No biggie; I picked it up and put it back in its place. But yesterday, I noticed that the soap had leaked out of the container. I picked up the bottle and saw this:
Environmental Stress Cracking of Polyethylene due to Soap
What an idiot I was. It was a polyethylene bottle with dilute soap in it and it had been stressed by the fall to the cement - a situation just begging for environmental stress cracking and that was what I got.

Environmental stress cracking (ESC) is where polyethylene and other plastics, when exposed to non-solvents and stress, break down unexpectedly. Soap and polyethylene. How can there by any interactions, especially at room temperature, especially when PE can withstand strong acids and bases, concentrated soaps and surfactants, bleach, hydrogen peroxide and more? And if you think you have an idea, then be prepared to explain why polypropylene doesn't experience ESC.

As you can imagine, I'll be on the lookout for a PP-based spray bottle for next year.


Previous Years

September 6, 2013 - A response to the ChemBark post (partially) about me

September 6, 2012 - Somewhere in a movie balcony...

September 6, 2011 - Polymorph Determination through Nanoindentation

September 6, 2007 - A resurgence of French?

6 comments:

fgthtyhsrty said...

supreme hoodie
golden goose sneakers
kyrie 5
birkin bag
hermes online
yeezy boost 350
jordan shoes
lebron 17 shoes
lebron 18
jordan shoes

오피 op-best.com said...


Hi there mates, how is all, and what you would like to say concerning this
article, in my view its truly awesome in favor of me.

Look at my web-site 부산오피

Economics Dissertation Editing and Proofreading Services said...

This article is interesting because it discusses how environmental stress cracking can affect curse words. I didn't know that this was a thing but it makes sense. I'm curious to know if there are any other words that are affected by this phenomenon.

The Daily Guides said...

The articles and blogs we accept are full of knowledge and information. Moreover, our site contains every slightest and detailed update about the trendy topic of the world. The passionates contributing to the knowledge and update we give forward are careful in managing the entire data cycle.

Best Online Assignment Help said...

Curses! Environmental stress cracking (ESC) is a type of failure that can occur in materials exposed to certain combinations of stress and environment. The stress can be either applied externally, as in a tensile load or internally, as in a pressure vessel containing a liquid or gas.

Emily Max said...

this blog is informative by the way our company is providing Assignment Help Manchester which can help all the students in the United Kingdom in their Assignment.