Stretchy film debuts
An experimental tape features a new coextruded film that alternates lengthwise "stripes" of stretch film with stripes of pressure sensitive adhesives. The result: the tape can conform to the shape of whatever it bonds and it can flex in use. Initially having developed a diaper tape, the company can vary the stripe pattern and the composition of the film and adhesive combination to meet a variety of application requirements-everything from living hinges to a providing a fixturative hold for assemblies.
Where's the bondline?
A new optically clear, UV-stable urethane adhesive bonds fiberglass, glass, metal, and a variety of thermoplastics-including PC, ABS, and acrylic. Called Urelane 6100-A/B, the adhesive can produce invisible bondlines needed for the assembly of some optical devices, computer components, and aircraft parts. The new adhesive exhibits polycarbonate-to-polycarbonate lap shear strength of 950 psi at room temperature and an elongation of 400%. It gels in two to three minutes, can be handled after an hour, and achieves a complete cure after two days at room temperature or two hours at 150F.
Quick cure epoxy
Got five minutes? That's all the cure time you'll need for this new epoxy. Appli-tec 5400 offers a Shore D hardness of 71 and a lap shear strength of 3,000 psi when cured at 25C. Offering a 1:1 mix ratio, the new epoxy can be supplied either in pre-measured static mixer cartridges or in two-part, pre-measured pouches.
Hot joint technology
As a low-cost alternative to traditional brazed or welded joints, NASA has cooked up new thermal elements that hold static joints together. Placed in the joint under a preload and heated, these gasket-like elements carry a coating that melts to form a connection in the joint. Depending on the application, the thermal elements can be heated with either an electrical current or external heat source. The coatings can be adhesives, thermoplastics or braze alloys. Potential applications for the new joints include automotive engine cooling system housings, a variety of piping joints, sealed electrical housings, and housings for marine engines and transmissions.
Plastic holds fasteners
A little dab of plastic can smooth the assembly process. At least, that's the goal of a fastener treatment called Stay-Put. The treatment employs a dollop of a polyamide material to provide a fixturative hold for nuts, bolts, washers, and rivets. First developed as a way to hold the back end of a Huck-bolt in place, the treatment has seen use in a variety of automotive, heavy transportation, and aerospace applications-including rail cars and thrust reversers. Stay-Put's polyamide is formulated to withstand continuous use at temperatures up to 325F.
Two new high-strength epoxy structural adhesives join composites, metals, and dissimilar materials. For temperatures up to 300F, Epibond 1590-A/B has an aluminum-to-aluminum lap shear strength of 5,800 psi and a Bell peel of 330 pli at room temperature. For temperatures up to 250F, Epibond 1595-A/B offers an aluminum-to-aluminum lap shear strength of 5,000 psi and a Bell peel of 82 pli at room temperature.
Two new Flashcure light-cure cyanoacrylate adhesives target applications needing an tack-free, instant cure. Flashcure 4304 is low-viscosity formulation for close fitting parts, while medium-viscosity Flashcure 4305 can fill gaps. Both products offer a secondary moisture-cure mechanism for areas that light cannot reach. Intended for medical device applications, both products are ISO-10993/ USP Class VI compliant.
Adhesive holds metals fast
Devcon Metal Welder, a methacrylate structural adhesive, targets a variety of metal bonding applications, creating load-bearing bonds with tensile shear strengths of 2,800 psi and temperature performance up to 250F. It bonds a wide variety of metals, including aluminum, cold rolled steel and stainless steel. It can also bond metals to plastics, including ABS, PVC, plexiglass, PMMA, polycarbonate, polyesters, and fiberglass reinforced plastics. Metal Welder cures at room temperature in one hour.