A Fireside Chat with Polymer Pioneers: Pipe & Film

Through a series of fireside chats, they will share insights that can help converters unlock competitive advantages, assess industry trends, and discover new techniques. In this first edition, we focus on the pipe and film sectors with Shell Polymer Pioneers Carl Baker and Dan Falla.

Shell Polymers Pioneers

Carl and Dan, let’s kick off by talking about the pace of change in your respective industries. What have you seen over the years? 

Dan: One of the most significant changes we’ve seen over the last decade or so has been in the technology of the equipment that processes polyethylene. The equipment manufacturers have unlocked a step change in their processes that brought major improvements in quality control. Through a combination of new motors and drives, gauge control and so on, they’ve increased output rates up to 40% and massively reduced the variability in film thicknesses. The latter point can bring major cost savings, as the supplier is not shipping a film to its customer that is thicker than it should be.

And of course, there’s the advent of multilayer co-extruded structures, which has been a game-changer. If you looked at a cross-section of film back in the early 1990s you would have seen a single layer. Some of today’s barrier films, such as those used for cuts of meat, feature up to 11 layers, with each layer having a specific function such as a moisture or an oxygen barrier, or providing physical strength.

The driving forces behind going from mono- to multilayer film have been cost and sustainability. You’re able to reduce your costs dramatically because you can use lower-cost polymers. And you can design thinner structures, which brings a sustainability benefit and dramatically improves the overall performance of the product itself.

Carl: Pipe is a little different in that respect. Because it’s so highly regulated, it’s one of the slower-moving markets and it can take many years for changes to happen. I’d say major innovation in the industry is on about a 20-year cycle, starting in the 1960s. The general view is that we’re on the third generation of pipe resins.

That said, I think in the last 20 years things have moved faster because technology has advanced at a higher pace. The advent of bimodal technology in the early 2000s was really significant. It has brought several important benefits.

For example, it enables longer guarantees. Whereas pipes used to have 10-year guarantees, the ones made today with bimodal technology typically have 50-year guarantees.

It also enables higher pressure ratings of about 13% for water and about 10% for gas, which further expands the market for polyethylene pipe.

So, does that mean opportunities for converters?

Carl: It does. There are lots of applications and industries that haven’t used polyethylene products until now for various reasons. We’ve seen sustained growth in markets like pressure pipe for gas and for water, industrial mining applications, all the way to irrigation and all those kinds of markets. I think polyethylene will continue to penetrate other market segments too.

And Dan, do you see any market opportunities for film companies?

Dan: Food packaging, which is the largest market segment, is constantly changing. The major brands are increasingly replacing containers such as metal cans and glass jars with polyolefin products. For example, there is strong growth in reverse-printed polyethylene terephthalate, which is being used for stand-up pouches. These pouches are not readily recyclable right now, but technology is coming where it could be an all-polyethylene structure providing similar types of gloss and printability to those you get with a polyester terephthalate foam with an oriented polyethylene.

Another opportunity may be beer packaging. Why does beer continue to be packaged in paperboard boxes? Why is that not collation shrink? I believe if the beer industry changed over to collation shrink it could reduce its costs dramatically.

Can you provide an example that demonstrates how you would work with a customer?

Dan: Sure. Let’s say a film company is keen to develop a more sustainable, recyclable alternative to the foam polystyrene tray with plastic overwrap that is commonly used in poultry packaging. They have observed that the sector is changing. It’s going to more towards sustainable options and they have had the idea of developing a pouch to put the chicken in.

We could help them trial a film structure to work in this market segment and have the desired oxygen transmission rate. Beyond that, we could also facilitate some market research on, for example, the sealant layer, or help identify key components or equipment that these products could go to.

Carl: Pipe producers often encounter concerns with the striping that they add to indicate the application. So, let’s say their striping is failing ultraviolet exposure testing. Working together, we’d recommend alternative masterbatches and do verification testing on them.

Or maybe their pigments are fouling the die and causing surface defects. One of the things we can do is to run their current formulation on our machines and try to find ways of solving the problem. Perhaps it needs a different masterbatch or a processing aid, or maybe it’s something else.

And you can do all this at your plant?

Carl: Yes, at our application hall – and that’s a point I’d like to emphasize. Most pipe extruders run 24/7/365, so not having to stop their own production line is hugely significant. Stopping the line for testing or troubleshooting causes problems, so they don’t want to do that.

Dan: I couldn’t agree more. We’ll have state-of-the-art multilayer blown film lines equipment, which will be a tremendous value to customers. It means they won’t have to shut their factory down to trial samples and do experiments, with all the lost productivity that entails. Instead, they can drive to our facility, because most of them are close enough, and do the experiments on our line.

There’s another benefit too. The equipment in our application hall will be large enough that they can produce film here and take it directly to their customer. I’m not aware of any other polyethylene producer that has commercial-size lines.

Carl, one of the biggest issues that affect pipe producers is the mixing of the masterbatch with the raw resin. Do you have any insights on this?

Carl: Yes. In some parts of the world, the resins are pre-compounded by the manufacturer, in which case the extruder doesn’t have to worry about the mixing. But in the USA and other countries including Canada and Japan, we favor salt and pepper mixing. So, we feed the raw resin to the extruder with a little bit of a masterbatch that puts a color or some other additive in there as required.

Sometimes the masterbatch doesn’t disperse evenly throughout the pipe, particularly in larger pipe. If it does, you need to look at the equipment design. You should also look at the masterbatch too. How did you make it? What’s the carrier resin?

What about the equipment that your customers are running? Are there any opportunities there?

Dan: Yes, there are. I’m a strong advocate of the latest-technology multilayer production lines. I’ve seen at first hand that they can have a dramatic effect on quality, consistency and output. I suspect it is going to be ever more difficult to compete in this business long term if you’re not running the latest technology.

And there are so many companies that could benefit from this. Of the 4,000–6,000 blown film lines in use across North America, about 80% of them are old monolayer lines.

What could be holding them back from upgrading? The capital expenditure?

Dan: I think so. But although it can seem expensive, the return on investment can be as short as a year. I was talking recently with a major equipment manufacturer and they can categorically demonstrate how it can save customers 3–4¢ a pound.

Carl: I’d have a similar message to pipe producers: stay up to date with the technology. Because things have changed and are changing, so you must constantly evaluate the equipment you’re running. For example, extruders are getting longer. Back in the 1960s, extruders tended to have a length/diameter (L/D) ratio of 20:1; the second-generation pipe production equipment this increased to 30:1.