My major bubble project of the summer and Fall has been documenting the color profile of bubble solutions made with Dawn Pro and Charmy at various dilutions. Included in the studies (which I have not yet published) have been comparisons of solutions at the same dilution but with different pH or different polymers. I have chosen 20:1 because I have really grown to like the colors and because the color profile is one that changes quite obviously when the film stretches.
Several weeks ago, I was looking at video of bubbles made guar-based and PEO-based juice and noticed that the guar-based bubbles showed the thinner "stretched" color profile earlier in their growth than the PEO solution. It was quite consistent. It occurred to me that perhaps PEO didn't make the film stretchier as conventional wisdom would have it. The PEO bubbles showed less signs of stretching. The bubble tubes were growing without the film thinning as the wick became emptier the way that the guar bubbles did. The thought occurred to me that perhaps the PEO makes the solution more slippery than the guar gum -- either that or the super-long polymer chains in the PEO that cause it to be self-siphoning might help the bubble pull solution from the wick.
I jotted down the observation and added at to-do item to look into the topic some more.
This evening, I was looking at video of a recent session in which I used two versions of eGoo that had different amounts of PEO. I noticed the same phenomenon. The solution that had more PEO did not shift to the "stretched" profile as quickly as the other solution if they shifted at all. Here are photos from the session. This is certainly not definitive....but I am starting to wonder...