Interior parts for public buses are designed for durability, safety, and appearance, an exacting balance that leaves little margin for tradeoffs. One such part, thr luggage cover for use on mass transit buses is produced by composites specialist Amtech LLC in Wapato, WA.

The cover measures 5 × 4 × 3 ft. and is fabricated in a deep-draw vacuum-forming process that generates a remarkable 40 in. (1,016 mm) draw. The interior layer is glass-reinforced epoxy vinyl ester resin; the core is a proprietary bonding material; and the outer layer is 0.180 in. gauge thermoplastic sheet from Boltaron in Newcomerstown, OH.

The original laminate had a gel coat surface that didn’t withstand the harsh conditions and occasional abuse the luggage covers receive in service and during assembly. “The finish didn’t hold up well in the field and needed numerous repairs,” he says.

In contrast, the proprietary Boltaron sheet, Grade 4800, with impregnated color, ensures that part-to-part aesthetics are consistent. The sheet also works better in deep-draw vacuum forming, getting greater surface texture resolution with fewer surface contaminants during forming.

The material deters graffiti vandals because the specified sand finish doesn't let graffiti from felt pens and other markers adhere well. It is easy to clean.

The extruded sheet is fire retardant and designed specifically for mass transit interiors. It meets ASTM E-162 and ASTM E-662 requirements for flammability and low smoke emissions and FTA, UMTA, and Docket 90A guidelines. The material has good impact strength, abrasion resistance, stain and chemical resistance, and thermoformability. It comes in custom colors and a range of textures, and maintains lot-to-lot consistency. The sheet is available in 0.040 to 0.250 in. gauges, widths to 60 in., and lengths to 120 in.

A newThe National Institute of Standards and Technology (NIST) material offers companies and researchers a badly needed source of uniform and well-characterized carbon nanotube soot for material comparisons and chemical and toxicity analysis.NIST has issued the world's first reference material for single-wall carbon nanotube soot. Distantly related to the soot in a fireplace or a candle flame, nanotube-laden soot is the primary industrial source of single-wall carbon nanotubes.

Thermoformed packaging such as blister packs and clamshells typically end up in landfills, even though many of them are made of PC PET, the material that is blow molded into soft drink and water bottles and highly recyclable. That’s a problem for manufacturers concerned about the sustainability of their products and product packaging. But realities of the economics of recycling will probably prevent the widespread recycling of thermoform-grade RPET for some time to come. (The “R” of RPET means the polymer comprises virgin material plus regrind, or recycled content.) In a pilot study conducted by thermoform packaging maker Dordan Manufacturing in Woodstock, Ill., the company shipped 50 of its RPET clamshells to a local recycling facility to determine how well the containers could be sorted. The automated waste-management facility that accepted the RPET samples sort different kinds of polymers using optics.

The equipment could not distinguish any difference between PET bottles and RPET thermoforms says Dordan Manufacturing sustainability coordinator Chandler Slavin. Theoretically, the two could be recycled together but this depends on a lot of factors, many of which are contingent on the sorting technology employed. In manual sortation systems, there are problems associated with the fact that clamshells and blisters come in all shapes, sizes, and materials, making it difficult to train personnel at recycling centers how to sort the packages by material type via visual cues inherent in package design. Most clear thin-neck screw-top beverage bottles are PET, making it easy to identify this recyclable from those destined for landfills, says Slavin.

Another issue: Industry experts suggest there may be fluctuations between the intrinsic viscosity (IV) of PET and RPET that would make them difficult to recycle together. The IV of a material, measured in deciliters per gram, depends on the length of its polymer chains; the longer the chains, the higher the viscosity of the material. Also, RPETs can comprise different ratios of PET, regrind, or recycled polymers. This is one reason why the National Association for PET Container Resources (NAPCOR) concluded it would be easiest to just recycle PET thermoforms together and keep them out of the PET bottle recovery system.

The recycling of thermoforms is an evolving situation, says Slavin. Consequently, there are no standard practices; all collection, sortation, and reprocessing practices are dependent on the end market of the recyclate, which differ from region to region. And information about recyclability of specific materials often gets handed down like folklore among thermoform manufacturers and other interested parties. “Waste management is a large, complicated, and mature industry slow to adopt new technologies and processes due to inconsistencies inherent in North American recycling behaviors and established patterns of material recovery,” she says. For example, “A package or material type will not be collected for recycling if there is no buyer.” Says Slavin. “And there will be no buyer if there is not a consistent quantity and quality available for reprocessing. Moreover, lots of post-consumer plastics collected for recycling get sold to China where the cost of manual sortation is less than the cost of domestic sortation. This subtracts from the available recycling stream in North America, making the supply-demand amounts necessary to sustain the process of recycling difficult to quantify.”

In addition, a community’s ability to recycle a package with limited recyclability, like RPET thermoformed containers, can be dictated by whether facilities are private or municipality owned, says Slavin. “Private facilities tend to be better run and maintained than municipally funded ones,” she says. “They also tend to be more economically sustainable. And they incorporate more sophisticated systems for sorting and reprocessing. Other factors include the geographical location of the facility (east vs. Midwest vs. West), which determines what types of materials are collected for recycling and technologies used, based on the available end markets.” And consider the collection scheme, says Slavin. “How the materials are collected for recycling – curbside, drop off, single stream, or comingled – determines how the material comes to the recycling facility,” she says. “This also affects how and what materials are collected for recycling and what sortation systems are used.” Complicating matters further, buyers’ specs, or the qualified indicators a buyer outlines to a supplier of PC plastics upon procurement, require the material be of a specific material type — for instance PET — and packaging type — like thin-neck screw-top PET beverage containers. For instance, most buyers of PET indicate they do not want bales with RPET thermoforms included in the mix for fear of contamination. This discourages MRF’s from making investments into the sortation technologies necessary to sort RPET thermoforms from look-alike contaminates like PVC.

The Sustainable Packaging Coalition (SPC) developed the Labeling for Recovery Project, intended to educate consumers on what types of packaging is recycled and what is not via a simple labeling scheme modeled off the U.K.’s OPRL, On-Pack Recycling Label. Under the scheme, the label lists the components of the packaging and the material it is made from. It is intended to tell consumers tangible information about what can and can't be recycled in the U.K. rather than what is assumed to be recyclable,” says Slavin. “The hope was to have consumers understand recycling based on the realities of the current system, thereby establishing a demand for increased material recycling. But in developing the initiative, the project team ran into some obstacles in regards to data applicability. Difficulties for them arouse such as how to determine the types of packaging recycled and the quantity recycled in different geographical regions; whether a community has access to a facility capable of recycling the packaging, and whether collection, end markets, and automated sorting systems are available. What is the quantitative and qualitative distinction amoung ‘recyclable,’ ‘limited recycling,’ and ‘not recycled?’ Where is the data coming from? When was the data collected and what was the method? What if data doesn’t exist for a specific packaging type? What about those programs that are not considered in the EPA’s figures, like mail-in programs such as TerraCycle in Trenton, N.J.” she says.

Industry figures suggest that the amount of American communities capable of recycling PET thermoforms is 30 to 59%, which falls within the ‘limited recyclability’ category as per the FTC Green Guides’ definition. “This is changing, however, as industry begins to take a more proactive approach to the recovery of packaging,” says Slavin. “I foresee the management of recyclables as shifting from municipally to privately owned systems, due in part to the success of techniques observed overseas.”

RESOURCES:

Dordan Manufacturing Co. Inc., www.dordan.com, www.recyclablepackaging.org

For more information, check out YouTube videos on “how recycling centers work” like http://www.youtube.com/watch?v=_GP3JuiX5BY.

Visit this link for a list by material type of what is recovered based on percent generation with the focus on containers and packaging: http://www.ftc.gov/bcp/edu/microsites/energy/documents/Green-Guides-Summary-of-Proposal.pdf

The document describes what is recycled and in what quantities thereby demonstrating what is not: http://www.epa.gov/osw/nonhaz/municipal/pubs/msw2008data.pdf

Slavin’s research culminated in the release of her Recycling Report: The Truth about Clamshell/Blister Recycling in America with Suggestions for the Industry. http://www.dordan.com/pdf/dordan_recycling_report.pdf

Terracycle, www.terracycle.net

A team of engineers at Purdue University has built a prototype of a machine that disinfects water using UV radiation from the sun, a potential boon for the world’s 800 million people who lack access to safe drinking water. The UV radiation inactivates waterborne germs by damaging them so they cannot reproduce. The device consists of a parabolic reflector with a transparent pipe running down the middle. Water flowing through the pipe gets exposed to the sun’s radiation during the day.

The trough-shaped reflector was made by lead engineer Ernest R. Blatchely III in his garage. To make the reflector reflective, the team lined it with aluminum foil. The trough itself is made of paulownia wood from a tree that grows rapidly in equatorial regions, an area which often doesn’t have sources of clean water. The wood is light, strong, and stable, so it will not warp, twist, or crack in climates that are either dry or humid, or those that swing back and forth between the two.

In tests at the college’s Indiana campus, the $100 device worked against E. coli bacteria, but not against the germs that cause cholera, typhoid, or cryptosporidiosis. The team plans on testing other, more-reflective materials such as metallized plastics, similar to the materials used to package potato chips. Such materials are said to be twice as reflective as aluminum foil. The team will also automate the process, adding timers and valves so they can control how fast water speeds through the pipe and how long it’s exposed to sunlight. Plans are to determine how much exposure to tropical sunlight is needed to inactivate the target pathogens, and then to program the timers accordingly.

© 2011 Penton Media, Inc.

Physicists at the Georgia Institute of Technology have used computer simulations to show that sufficiently strong electric fields can solidify liquids into crystals at temperatures and pressures under which the material should otherwise remain liquid. The process is termed electrocrystallization, and was first described by Geofrey Taylor in 1964 while studying the effects of lightning on raindrops.

The simulations used molecular-dynamics software developed at Georgia Tech. It let the scientist examine the behavior of a 10-nm diameter drop of formamide, a material consisting of polar molecules with a dipole moment more than twice as large as that of water. The simulation revealed that an electric field of less than 0.5 V/nm made the spherical drop elongate slightly. When the field approached 0.5 V/nm, the sphere transformed into a needlelike structure with an aspect ratio of 12, with the long dimension oriented along the direction of the field.

Higher fields brought higher and higher aspect ratios. And when the field was 1.5 V/nm, the simulation showed the droplet solidified into a single formamide crystal. Ramping the field down led to the crystalline needle melting, eventually returning to a spherical shape. Researchers theorize that the transformation to a crystal arose from the molecules arranging themselves into a lattice, which increased the interactions between the positive and negative ends of neighboring molecules’ dipoles. This minimized the free energy in the droplet and caused solidification.

Further research will uncover more about the microscopic origin of material behavior and could lead to field-controlled drug delivery, printing of nanostructures, and aerosols.

© 2011 Penton Media, Inc.

Elastocon 2850PE and 2865PE grades of thermoplastic elastomers Shore A hardnesses of 50 and 65, respectively, are FDA compliant, and are odorless. The transparent polymers are formulated for extruding and overmolding and coextruding onto polyethylene.
The formulations have rubber-like properties, colorability, a good surface finish, and UV stability. They are latex-free nad comply with RoHS and California Proposition 65. The 2850PE and 2865PE grades are available as pellets in 1,000-lb quantities.

Elastocon TPE Technologies, Inc., P.O. Box 463, Rochester, IL 62563, (888) 644-8732, www.elastocontpe.com

In Industrial Design – Materials and Manufacturing Guide (John Wiley & Sons, 2008), author Jim Lesko claims the famous term “form follows function” would be better restated as “form is the resolution of function.” In his definition, product function comprises two main components. One is “performance-specification demands, including all user-friendly aspects.” The other is cost and manufacturability. When designers forget about the “user-friendly” aspects, the result is almost always a bad design.

Though it’s not mentioned in the book, take the case of a lowly toilet-paper holder. The designers neglected to consider the fact that all toilet paper rolls are not necessarily the same. The result is a holder that often puts users in an embarrassing position. No matter how they try, they cannot grab enough of the end of the roll to pull down a piece and take care of business.

The designers probably didn’t neglect research studies, finish color, texture, safety of materials, manufacturability, and all the other factors of product analysis at this stage. But the holder is an example of a bad design. Why? There is no option for the device to work with a flawed roll of toilet paper. This should have been a major design consideration, especially because the holder is intended for use with large-diameter, industrial toilet-paper rolls (which only unroll when they fit in the holder perfectly).

Now consider what happens when the first roll in the holder has a distorted mounting hole.

The poorly formed mounting hole causes the roll to cock, jamming it against the holder sides such that users can’t pull off the tiniest shred of paper. Worse yet, a cocked roll leaves no room for a user to reach in and remove the first roll to manually unwind a length to use.

Nor is this a problem for maintenance personnel. It would be impractical to ask them to inspect every roll for flaws.

Do you agree this is an industrial-design issue? Should holder mounts be redesigned to better accept nonperfect holes? Or should facilities 100%-inspect all incoming rolls?

© 2011 Penton Media, Inc.