Film Extrusion
Polystyrene Blown Film Starts to Get Some Respect
It has kept a low profile for the last 40 years, but more blown-film processors are starting to take a look at PS for breathable packaging and cellophane replacements. A couple of dozen processors worldwide have kept this technology quietly to themselves—but not for much longer.
Read MoreTwo More LLDPE Families for High-Performance Blown Film
Two new families of “enhanced” hexene-copolymer LLDPE resins for blown film are said to offer excellent impact resistance and outstanding hot-tack and heat-seal properties. One resin family reportedly can replace high-end octene LLDPE while the other is said to equal or surpass the performance of VLDPE or metallocene LLDPE (mLLDPE).
Read MoreUnderstanding Grooved Feed
U.S. processors still have some catching up to do when it comes to getting the most out of grooved-feed extruders. But decades of European experience offer lessons on how to use grooved feeds to run even resins like TPU, nylon, and PET.
Read MoreThe New Look in Plastic -- It's Paper!
Synthetic paper based on filled polyethylene or polypropylene film has been around for decades without causing much excitement--until recently.
Read MoreNew Catalyst Technologies Add Muscle to LLDPE Films
For processors looking to extrude stronger and tougher films, two firms recently came out with hexene-copolymer LLDPEs based on new catalyst technologies. Both resin families are poised to compete with octene LLDPE and metallocene LLDPE (mLLDPE), as well as other "super-hexene" grades.
Read MoreCapacitance Gauges Come of Age For Blown-Film Thickness Control
Thanks to recent technical advances, relatively inexpensive capacitance thickness gauges reportedly are now stable enough for reliable closed-loop control, not just monitoring thickness variations. Another big step forward for capacitance gauges is the arrival of non-contact heads that can be mounted on the bubble instead of farther downstream on the layflat, thereby allowing quicker response to thickness variations.
Read MoreKeep It Dry: Optimize Moisture Barrier in PE Films
When people talk about improving barrier properties in multi-layer food-packaging films, many of them think only of special barrier resins and overlook the role of the polyethylene that makes up the bulk of most films. The PE in a coex film can also be optimized to contribute to barrier.
Read MorePP Engineering Alloys Branch Out Into Molding, Extrusion, Thermoforming
The Hivalloy line of in-reactor grafted alloys of polypropylene and amorphous resins from Montell Polyolefins, Wilmington, Del., is expanding its market reach with new grades, new developmental alloy families, and dramatic new applications. Besides injection molding, developing applications now include thermoformed sheet and even barrier packaging films.
Read MoreTime for a Switch to Electric Heater Rolls?
Web processors and converters who use liquid-heated rollers for orienting, annealing, laminating, and embossing should take a look at recent advances in electric-heated rolls. You could get better temperature control with less maintenance and downtime.
Read MoreAir Rings--Make Them Work for You, Not Against You
Air rings do more than just blow cooling air on your film. Their complex aerodynamic effects also help form and stabilize the bubble. Yet operators often misuse air rings because they don't understand how the stabilizing function works. Here's a practical guide to making an air ring be your trusty helper instead of an unruly troublemaker.
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