In Berlin, I ate dinner at an Asian restaurant near the laundromat I used earlier in the day. I was going to ride back to my room and eat where I had a good internet signal. But it was a nice night so I sat at one of the two tables in front of the restaurant. A woman in her 50s was eating at the other table. She heard me speaking English and asked where I was riding. We talked about traveling on a bike and about how bicycles were everywhere in Berlin and in Germany. She is a documentary filmmaker. She asked about my job. I told her I am retired, but my last job was at a museum of the history of chemistry.
She really brightened up at that! It turns out she made a documentary about the history of plastic chairs--polyethylene chairs that are very common in Germany, especially the former East Germany. Sybelle said, "The chairs themselves were boring. Just blocks of plastic. So I researched the history. That was fascinating!" She was able to interview one of the two chemists who discovered the process for making polyethylene and polypropylene. She learned a lot about chemisty and polymer chemistry. She knew of the existence of polyvinylidene fluoride, but did not know how it differed from Teflon. I could explain the difference in the two molecules.
Outside of a professional chemistry setting, I never met anyone on the street in the U.S. who knew or cared about polymer chemistry, of for that matter who had ever heard of polyvinylidene fluoride.
We also talked about politics. When she grew up, she was told people like me, the American Army in Germany, were occupying West Germany, but since she lived in Berlin, she knew very well that the wall was to keep East Germans in, more than to keep the rest of the world out.