As my mind meanders...
I ponder which substance will ultimately replace "plastic". I put that term in quotes, acknowledging the existence of many interpretations, such as "Leftoverture," which I suspect is more familiar to others than I could ever really comprehend. I have heard discussions on graphene derivatives and a business in India engaged in 3D printing a metallic composite of some kind.
I am intrigued by what the next 25 to 30 years may entail, considering the advancements made over the previous century. It is astonishing.