SCIENCE/TECHNOLOGY
Dendrimers Nearing Availability For Commercial Evaluation Now that is about to change. At DSM in the Netherlands, where dendrimers are being made in multikilogram lots, samples soon will be going to laboratories and enterprises around the world. If the results of investigations live up to expectations, production could become a commercial reality well before the turn of the century. "A dendrimer is more than a new product. It is a completely new kind of molecule," notes Jos Put, head of DSM's research department responsible for engineering plastics, resins, and new polymers. "We can provide a novel chemical building block that will lead to a whole new line of products whose chemical and physical parameters can be con-
• DSM is turning out multikilogram lots of the "new hind of molecule, " portending commercial production by 2000 Dermot A. O'Sullivan, C&EN London endrimers have been attracting increasing interest of late. The problem has been that sufficient quantities of the multibranched oligomers haven't been available for any degree of concerted evaluation because they are difficult to make.
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trolled." Dendrimers, he adds, should have a multiplicity of uses ranging from adhesive improvers and viscosity modifiers to applications in agriculture, perfumes, and pharmaceuticals. Products made at DSM's facilities in Geleen, in the southeastern corner of the Netherlands, belong to the polypropylenimine series of dendrimers. They result from repetitive reaction of a primary or secondary amine with acrylonitrile—using the Michael addition reaction—followed by a heterogeneously catalyzed hydrogénation using hydrogen and Raney cobalt. Ellen M. M. de Brabander-van den Berg and Bert W. Meijer, on whose research DSM's process is based, will be detailing their work
DSM's poly(propylenimine) dendrimer has 64 functionalities
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