Heat 'em, magnetize 'em, dissolve 'em The advantage of plastics or polymers isthat they are lightweight but have a strengthand stiffness comparable, on a weight toweight basis, to steel and metals in manyapplications. Joshua Otaigbe has spent 16years researching these, compounds. Here area few of his projects. Homegrown plastics Otaigbe's project focuses on soy proteinplastics, which were developed to biodegradeafter serving their function. The problem withsoy protein plastics, he said, is that theydissolve too quickly in water, limiting theirpotential uses. His new formulation makesthe material more moisture resistant,providing greater control over thebiodegradation process. The work could leadto several new uses for soy protein plastics,such as food packaging, medical sutures, evensporting goods. Atomized plastics Otaigbe and a former graduate studenthave demonstrated that better processing control for many polymers is possible by usinggas atomization methods. This work benefitedfrom the patented research by Ames Lab's IverAnderson, who did his work with metals.Otaigbe atomizes his polymer materials in asimilar way. In a 12-foot-high transparentchamber, he blasts a stream of molten polymerwith highpressure nitrogen gas. The processproduces uniformly fine spherical powders ofthe plastic, which can be shaped into complexparts, or used in inks, pigments, powder spraycoatings and paints. Driven plastics Otaigbe's "cyclomer" technology addresses aproblem scientists have in making toughthermoplastic composite materials. Thesestructural materials combine a polymer with areinforcing fiber for strength. Current methodsof melting the polymer prior to molding lead toproblems, due to the gooey, gunky nature ofthe melted plastic. Otaigbe doesn't melt thepolymer until it has been vacuum-injected intoa mold with the reinforcing fibers. Like heating a prepared food dish in amicrowave, he subjects the compound toheat for a very short period of time. Theresult is a tough, durable plastic part.Otaigbe thinks the process might spur aresurgent interest in polymer auto bodyparts not seen since the Pontiac Fiero of the1980s. Magnetized plastics Permanent bonded magnets are a $400million market and are used in consumerproducts from cars to computers. But theyare made from rare earth metal alloys, whichare heavy and hard to process into shapes.Otaigbe recently received NSF funding toexplore melting polymers with the rare earthmagnetic alloys to make magnetized plastics.He thinks this project could lead to magnetsthat are 30 to 40 percent lighter and easier toform into shapes than the pure metal alloymagnets, Otaigbe also expects this research toaddress the problem of thermal corrosioninherent in the pure magnetic alloy powders. |