(hint #1) Being able to play whatever I want has been a central theme to my own discovering how to play guitar. I've been on that path for 37 years, and it's enabled me to uncover, test and refine a unique, skill generating learning approach.
It is important to note that urethane foam is most commonly used to refer to a material made from polyurethane. The urethane reference in this name is to the type of links, also known as carbamates, that join the units in polyurethane.
A polyurethane coating (or urethane floor coating), is a highly flexible, highly abrasion-resistant floor coating that is known for its shine and longevity. Developed in 1937 by I.G. Farbin, these materials were used to create gum rubbers, rigid foam, and elastomers.