Show highlights: ACMA's COMPOSITES 2012

The American Composites Manufacturers Association (ACMA) hosted the COMPOSITES 2012 conference and trade show Feb. 21-23 in Las Vegas, Nev., USA. CompositesWorld was there and offers highlights of presentations and new products.

The American Composites Manufacturers Association (ACMA, Arlington, Va., USA) hosted the COMPOSITES 2012 conference and trade show Feb. 21-23 at the Mandalay Bay Convention Center in Las Vegas, Nev., USA. CompositesWorld was there and offers this report of highlights from the event.

In line with the general spirit of optimism and growth at the event, conference presenters shared some insights on current research and development efforts. Jeff Martin of Martin Pultrusion Group Inc. (Oakwood Village, Ohio) explained his company’s efforts in the area of pultruding with two-part polyurethane resins, in contrast to traditional thermosets. Polyurethane (PU) resins generally provide higher mechanical properties than standard thermosetting resins typically used in a pultrusion line, with better shear, transverse tensile and impact vallues. Because of this, pultruders can eliminate some higher-cost reinforcements, such as fabrics, often needed for strength, and part wall thickness can also be reduced, for lower overall part cost. PUs don’t require styrene, and PU parts offer good corrosion and fire performance, with better surface finish that a standard thermoset. Drawbacks include difficulty with color stability, weatherability issues and a higher specific gravity, since a higher glass/resin ratio is needed to capture and hold the resin as it travels through the production line. An injection die, rather than a resin bath, is a necessity and hardware costs are higher. Martin says the payback is a better-performing part that opens up huge markets for pultruders, including shelving and ladder rails.

Martin’s paper was followed by a talk on polyurethanes themselves, and how the resins have been improved for better fiber impregnation and higher line speeds, by Michael Connolly, product manager at Huntsman Polyurethanes. Connolly’s paper, which included an interesting discussion of Huntsman’s modeling tool for die and line optimization, won the Best Paper Award for the pultrusion category. CompositesWorld’s editors discovered another pultrusion innovation from 4D Parts Direct (Oakwood Village, Ohio), a new company making complex forming guides for pultrusion dies via rapid prototyping. The printed parts, formed in a few hours from a 3-D model, can be plated with nickel to directly replace parts previously made of machined aluminum or sheet metal, at a fraction of the cost. Ideal for prototying, the method can produce mandrel forming surfaces and even low pressure wetout devices.

Another compelling presentation was given by Dr. Brahim Benmokrane, a professor at the University of Sherbrooke in Quebec, Canada. He described a new project in which a 40-year old, two-way flat slab parking garage was rehabilitated using only glass fiber reinforced polymer (GFRP) reinforcing bars for one level — roughly 40,000m/24.5 miles of bar products — to achieve a construction industry first. Benmokrane says the new slab is performing as predicted, based on in-situ monitoring instrumentation, and that slab life could be 100 years.

In the exhibit hall, the Awards for Composites Excellence (ACE) product display area was once again awash with interesting concepts and innovations. One example was a new press curing system with rubber-coated tools (PCRT) presented by Avanti Composites, a division of Kintz Plastics (Howes Cave, N.Y., USA). As an out-of-autoclave alternative, the process allows lower-cost tooling and shorter ramp times, at a fraction of autoclave energy costs. Acell (Milan, Italy), featured in the February 2012 issue of Composites Technology magazine (see link at right), presented the Compass House concept, a modular prefab housing design using the company’s patented compression molded panels intended for emergency disaster housing or other quick-build applications. A new glass/polyester pallet (see photo at left) concept from Plastics Research Corp. (Ontario, Calif.) is made in a compression-molding process that produces extremely uniform parts with exact dimensions, critical to operations that use robotic/automated palletizing methods. The pallets are also consistent with food handling regulations and much more durable than current wood pallets.

ACMA offered several conference sessions designed to update composites manufacturers on styrene's recently listing in the 12th Report on Carcinogens (RoC), issued last June by the National Toxicology Program (NTP) under the U.S. Department of Health and Human Services (HHS). ACMA lobbied heavily to keep styrene, an important polyester curing agent, out of the RoC, and now is working to get it removed. George Cruzan, principle of ToxWorks, which has worked with the ACMA to fight the RoC listing, offered an update on the latest styrene toxicity data, as well as his thoughts on the prospects of delisting the material. His detailed presentation reviewed in particular genetic components involved in styrene metabolism in mice, rats and humans. In short, he said that new human/animal data contradict the NTP conclusion regarding potential styrene toxicity and that the weight of evidence indicates styrene does not cause cancer in humans. NTP will consider delisting a material if data support the action, but Cruzan said emphatically that "NTP will never delist styrene, no matter what the data say," contending that the NTP is determined to keep styrene on the RoC. The National Academy of Sciences has agreed to review some of the styrene toxicity data and, if it agrees with the ACMA that styrene is not a threat, might force some change at NTP that could lead either to styrene delisting or a change in how NTP assesses chemical toxicity. For more on styene's path to the RoC, see story at right.

On the show floor, many new products were on offer. Entropy Resins (Gardena, Calif.) and Dixie Chemical (Pasadena, Texas) showed new bio-based resin systems with high percentages of bio content. New reinforcements were evident at the Chomarat North America (Anderson, S.C.) booth, which highlighted its new C-Ply Bi-angle material being promoted by Dr. Steven Tsai at Stanford University, and at the Wm. T. Burnett & Co. (Statesville, N.C.) booth, where Polyweb C — a commingled nonwoven glass mat with polypropylene resin material — was exhibited as a thermoforming option. Materials Innovation Technologies (Lake City, S.C., USA) introduced MIT-RCF, reclaimed 787 Dreamliner carbon fiber in roll goods form. It's a wet-laid, nonwoven blanket of radomly oriented intermediate grade carbon fibers, with areal basis weights of 50 to 500 gsm. HK Research (Hickory, N.C., USA) introduced a new polymer called Revolution, a gelcoat-like material that offers 6 percent elongation and excellent water and UV resistance. Photos at left show tradtional gelcoat cracking under bending load, compared to Revolution, which shows no cracking under the same load.