No, Ronda Rousey’s face is not made from polyvinyl.
Yet, many comparable (and non-animated) punching bags, such as the one pictured below, are indeed crafted from the world’s haymaker of fossil fuels: petroleum. Without it, modern punching bags wouldn’t last as long, be as susceptible to abuse, and be as resilient to tearing.
If you’ve ever been to or seen an old boxing gym, the majority of classic, old-fashioned bags are made of leather; it is not uncommon to see cracks, splits, and duct tape holding together 70+ pounds of material. However, as newer, cheaper, and subsequently longer lasting designs came along, it appears that the industry of punching bag manufacturing has bought into the uncommon tensile strength of polymers.
Synthetic polymers are big molecules capable of adhering tightly to one another, creating the ( the unique and often unfound in nature) physical properties of many plastic or rubber items. The benefits of these long chains include their ability to stretch, become tangled up, and adhere to each other, much like a strong magnetization of two objects. By weight, polymers are — in some applications — stronger than steel. They are even employed in the manufacturing processes of many products that take a much heavier beating than a punching bag — think engine components, firearms, and more; as such, even months-worth of brutal punches from the #1 pound-for-pound fighter in the world won’t do much to damage a synthetic bag.
Petroleum is used throughout the punching bag-making process. First, vinyl or otherwise petroleum-derived synthetic material is cut using lubricant-powered machinery. The rest of the process requires extensive use of powerful machinery including the air-powered insertion of the bag filling. While nobody knows for sure what goes in a punching bag (generally — at least for low-end bags — this tends to be old, used clothing. See video below.), they are packed unbelievably tight, so that the pressure provides a good surface tension to absorb a blow.
It may be brutal, it may be bloody, but fighting is a part of human history.
Let’s just be glad that about 80% of the punches thrown land on polymers, not people.
SOURCES
http://www.madehow.com/Volume-7/Punching-Bag.html