Nov_Dec_AMP_Digital

A D V A N C E D M A T E R I A L S & P R O C E S S E S | N O V E M B E R / D E C E M B E R 2 0 1 7 1 3 SILKWORMS PULL TEXTILE INDUSTRY IN GREENER DIRECTION Scientists at the University of Shef- field, UK, discovered that animals such as spiders and worms spin silk not by pushing it out of their bodies, as was previously assumed, but by pulling it. Mimicking that pulling process in an industrial setting could make textile manufacturing more efficient and en- vironmentally friendly. To run their ex- periments, researchers adapted a rhe- ometer—normally used to measure viscosity—into a highly sensitive spin- ning wheel. Using a combination of computer models, experimental data, and practical measurements, the Shef- field team discovered that pushing un- spun silk through a worm’s silk gland would require an amount of force impossi- ble for an ani- mal of its size to generate— more pressure than in a firing diesel engine. However, the force required to pull silk from the animal’s body, known as pul- trusion, is well within the silkworm’s capacity. Currently, textiles such as nylon and polyester are manufactured by ex- truding a liquid feedstock through a dye, then solidifying it using extreme temperature change and exposure to harsh chemicals. Silk, which solidifies at room temperature leaving only wa- ter as waste, is a promising green alter- native to these synthetic fabrics. Until now, industrial silk production meth- ods have proven arduous and time-con- suming. Understanding the natural pul- trusion process is the first step in de- veloping an industrial method for effi- cient silk production, say researchers. www.sheffield.ac.uk . RARE EARTH RECYCLING FINALLY MAKES CENTS Researchers at the DOE’s Critical Materials Institute, Ames, Iowa, devel- oped a promising new rare earth mag- net recycling process that is cleaner and greener than traditional methods— and potentially profitable. The process dissolves magnets in an acid-free solu- tion and recovers high purity rare earth elements without using hazardous min- eral acids or producing toxic fumes. The technology, which has been applied to waste materials from U.S. magnet pro- cessing plants, is remarkably selective in recovering rare earth elements, even from electronic waste. In shredded computer hard drives, for example, rare earths were selectively removed from waste without pre-sorting or pre-con- centrating the materials’ magnet con- tent, reducing steps and costs. Economicandenvironmental chal- lenges have largely prevented rare earth recycling from being a viable solution to the scarcity problem, but the new process could change that. Not only has it been adapted to re- cover rare earths from Nd-Fe-B and Sm-Co magnets, it can also recover oth- er marketable byproducts from elec- tronic waste for further recycling, in- cluding copper, chromium, and nickel, enabling the process to pay for itself. cmi.ameslab.gov. PROCESS TECHNOLOGY Shredded electronic waste (top right) is processed into rare-earth oxide. New insights into how animals spin silk could lead to greener ways of producing synthetic fibers. Specialty chemicals producer CRC Industries Inc., Horsham, Pa., will acquire Weld-Aid Products, Detroit. Weld-Aid’s major business units in- clude an aftermarket division for welding-related cleaning and lubrication products and the zinc rich coatings division, which serves the galvanizing and infrastructure markets. Additionally, the company markets products such as zinc coatings, anti-spatter, and lubricants. crcindustries.com . BRIEFS United Technologies, Farming- ton, Conn., will purchase flight deck maker Rockwell Collins, Cedar Rapids, Iowa, for $22.75 billion. Rockwell Collins will merge with United Tech’s aero- space division to become a new unit named Collins Aerospace Systems, which will make air- plane seats, landing systems, and other parts for commercial and military planes. The deal should be complete within a year. utc.com .