Multiblock copolymers as polymeric surfactants: are “pancakes” better than “dumbbells”?

It is suggested that multiblock copolymers which form a pancake at the interface between two incompatible homopolymers would be more efficient as compatibilizers than di- or triblock copolymers. Less of the multiblock copolymers would be lost into the bulk phases as micelles or mesophases than di- or triblock copolymers if some degree of irregularity is included in the multiblock architecture, either in block length or chemical sequence distribution, without compromising the thermodynamic driving forces which localize the copolymers at the interface. This molecular design strategy is aimed at reducing the ability of the surfactant to form a separate phase, thereby increasing the interfacial activity in a nonequilibrium system with a large interfacial area. The multiblock loops which would preferentially orient into the most compatible homopolymer phases would have to exceed a certain critical size in order to avoid the entropic penalty of having an extremely flat pancake, and to provide good adhesion between the bulk phases.     

Sialyl Lewisx: A “Pre‐Organized Water Oligomer”?

Organized and released: Sialyl Lewis(x) (sLe(x)) represents a "pre-organized water oligomer", that is, a surrogate for clustered water molecules attached to a scaffold. The impetus for sLe(x) binding to E-selectin is shown to be the high degree of pre-organization allowing an array of directed hydrogen bonds, and the entropic benefit of the release of water molecules from the large binding interface to bulk water (see picture).     

Catalytic Synthesis of Ammonia—A “Never‐Ending Story”?

Nitrogen atoms are essential for the function of biological molecules and thus are and important component of fertilizers and medicaments. Bonds to nitrogen also find nonbiological uses in dyes, explosives, and resins. The synthesis of all these materials requires ammonia as an activated nitrogen building block. This situation is true for natural processes and the chemical industry. Knowledge of the various techniques for the preparation of ammonia is thus of fundamental importance for chemistry. The Haber-Bosch synthesis was the first heterogeneous catalytic system employed in the chemical industry and is still in use today. Understanding the mechanism and the translation of the knowledge into technical perfection has become a fundamental criterion for scientific development in catalysis research.     

“What is KRI?” – R&D based on excellent tradition and innovation –

As far as KRI's clients were concerned, KRI's appeal was not only in having researchers who had a high level of expert knowledge, but it was also in the efficiency with which high risk jobs were conducted, and the speed of response time, especially when corporations made comparisons with their own in‐house labs. KRI, while being a facility for contract research, is also capable of becoming a profitable corporation, mostly thanks to the adoption of this system. KRI sincerely hopes to continue serving as a group made up of quality professionals who embrace a dream, and to contribute to society through its achievements. At the same time, the company strives to be sensitive to changing needs, and, of course, to conduct R&D and consulting activities which will ensure success for its clients.