Science in Sports blog: TPEs in various sports

AKRON—When I first began writing for Rubber & Plastics News, I was overwhelmed by the amount of rubber and plastics that occurred in my everyday life that I never paid attention to … and that I cannot stop paying attention to now.

One of the areas I thought we could discuss more frequently is the use of rubbers and plastics in the sporting world, from safety components to the core of the equipment to accessories. It is everywhere. Many of the sports we play and watch today could not be mastered the same without our industry, so we should give ourselves a strong pat on the back. Because of this great contribution, I want to highlight different uses in a monthly Science in Sports blog series that we will post to rubbernews.com.

To kick off the blog series, I spoke with Jennifer Tomes, director of marketing for Star Thermoplastics Alloys & Rubbers Inc., about how much thermoplastic elastomers are used across the board in sports, from archery to water sports to golf and many places in between.

Grips

Grips are an important feature on sporting equipment because they need to have both a soft touch and “grippiness” to it, Tomes explained. When Star Thermoplastics makes the material, it could have hardness to it, but most grips need to be designed with impact resistance.

When I go to the driving range, I never consider what it would be like if, when I swung the club, I would begin to feel vibrations all the way up my arm. However, that is what would happen without a proper grip.

This can go for other sports, such as mountain biking, as well.

“We can put some vibration damping qualities and attributes into the grips that will help the impact resistance for the muscular-skeletal system, and then reduce wear and tear on our bones and joints,” Tomes said.

“So it's a safety factor as well as a comfort factor.”

While thinking of golf, it is easy to see how comfort plays into the grip. However, when thinking about firearms and even fishing, the safety aspects are also prevalent.

In archery, so much is reliant on the grip.

“Archery is a really fascinating sport, and it has evolved so much from just the bow and arrow … It really has come to a point where it's really true science and an art combined,” Tomes said.

While the grip is important for vibration damping, the more important aspect is that there needs to be silence in the woods while hunting.

What would happen if Katniss Everdeen of The Hunger Games pulled back on the string of her bow, and it made a loud noise? It would scare away the animal she was hunting. The odds would not be in her favor. 

There is a real silence to the sport, Tomes said, so creating the right formulation of TPEs is important to the total experience of bow hunting. If the vibration makes a noise, it disrupts the whole process.

With newer archery products, which are designed to have strength and power, grips must be able to absorb the vibration that goes along with that extra power, she said.

Additionally, if a hunter has a rifle sling on, it will be sliding up and down on his or her shoulder, which could be disruptive. Over time, their shoulder could start hurting without any impact resistance material there, Tomes said. By putting a soft surface on the shoulder, it allows the hunter to continue much longer than they could without that support.

Golf discs

One sport all about TPEs is golf discs. In case you don't know, disc golf is an up-and-coming sport, played similarly to golf but with flying discs instead of clubs. These courses are generally set up in local parks.

The game is played with a series of flying discs that resemble Frisbees, Tomes said, but they have different weights and different sizes associated to them, just like golf clubs.

“When we look at using TPEs in something like a golf disc, we look at how to adjust the formulation of the TPE material to allow it to have different specific gravities that would keep it within compliance of the golf disc sport,” Tomes said, adding that durability also is a factor.

This is the same concept of golf clubs: a driver might weigh more than a putter, but a driver needs to have the durability that allows it to have an impact over a long range, thrown at a pretty high speed.

When figuring out what TPE properties need to be put into a golf disc, Tomes said it is not just about the material, but it also is about the design. The company must produce a product that puts all those pieces together, combined and synthesized to a point where it is a disc that is comfortable and accurate to throw and has enough endurance to be used repeatedly.

“Because the sport is evolving, our knowledge about how to address it evolves as well,” she said. “And the endurance of the products has not always been there, or it's been difficult to achieve the weight with good balance.”

Water sports

The biggest question in regards to TPEs and water sports is figuring out what the equipment needs to do. Tomes said Star Thermoplastics needs to answer this question: When we have something that we're doing in the water, do we want that material to float or to sink?

“If I wanted to have swim fins that I was going to float on the water and I was going to go snorkeling, I'd want to have the fins so that they floated,” she said.

This would be especially important if a company was making these fins for a fin rental agency because it wouldn't want all the fins to sink to the bottom of the water only to be recovered. On the flip side, if fins are being used by a scuba diver who is swimming to the bottom of a body of water, the fin material needs to be able to go deep underwater so the diver's feet are not floating above their body.

Star Thermoplastics needs to incorporate different elements within each of those formulas based on what is needed.

Some other factors with TPE use is how much the item will be out in the sun, how much color is needed in the material and how much UV-resistance is needed. Tomes said swim fins and scuba fins both can be all sorts of colors; however, scuba fins generally have more black in them because black inherently has more UV-resistance properties. 

Besides fins, TPEs are also used for surf boards. For instance, when a surfer grabs his board, he doesn't want it to slip out of his hands on first grab.

Tomes said that “having some wet and dry gripping properties is something we can formulate into our TPE and make it appropriate for that specific application.

“There are a lot of things that when we talk about water sports, we look at TPEs slightly different than we would maybe, golf discs,” she said.

For instance, when producing straps for underwater camera or flashlights, a wrist strap works well as it must provide the ability to move around freely, but still have that apparatus strapped to a wrist. However, it needs to have that wet/dry grip. A person needs to be able to put it on above the surface as well as below. 

“With everything out there, we are always looking and seeing what we can be doing not just to improve our product, but improve it for the specific applications that are on the market that it's being used in,” Tomes said.

Evolving technology is prevalent in sports equipment industry, but one area Tomes said is picking up pace is the new active cameras, such as the GoPro. She expects a need will arise for more accessories to protect them and to utilize them better.

“I would expect that TPEs are going to have an impact in that market as well,” she said, adding this is trend in which Star Thermoplastics is participating.

Whether it is on land or in water, TPEs are a big part of sporting equipment that we use on a regular basis. How many kinds do you use? Let me know at [email protected] or on Twitter at @jenniferkarpus.