Keller, Andrew

Keller, Andrew (1925-99) Hungarian-born British chemist who... 

Andrew Keller (1925-1999) who in 1957 found that the polymer polyethylene, in unbranched form, could be crystallised from solution, and at once recognised that the length of the average polymer molecule was much greater than the observed crystal thickness. He concluded that the polymer chains must fold back upon themselves, and because others refused to accept this plain necessity, Keller unwittingly launched one of the most bitter battles in the history of materials science. This is further treated in Chapter 8, Section 8.4.2. 

CAROL CREUTZ, ANDREW D. KELLER, HAROLD A. SCHWARZ, NORMAN SUTTN, and ARDEN P. ZIPP... 

Acknowledgments This research was supported by the Division of Basic Energy Sciences of the U. S. Department of Energy. Andrew Keller was a participant in the Brookhaven National Laboratory Summer Student Program (1980). Arden P. Zipp was on sabbatical leave from SUNY, College at Cortland. 

Besides the development work earned out in Tubingen, Joachim Buddruss in Dortmund, Germany, as well as Harry Dorn in Blacksburg, USA and Charles Wilkins in Riverside, USA, have to be named as the first pioneers of on-line LC-NMR. Major applications employing LC-NMR have been performed by Tony Keller, Manfred Spraul, Ian Wilson, John Lindon, Jeremy Nicholson and Alfred Preiss. The nanoliter approach has been pioneered by Jonathan Swee-dler, Andrew Webb and Timothy Peck. 

He received his Ph.D. in summer 1940 and firmly wished to stay in fundamental research. He was offered a post at St. Andrews University which he could not take up because of World War II. Instead he was assigned to a war problem at Cambridge involving the synthesis of the then unknown 1,3,5,7-tetranitro-naphthalene, which Sir Robert Robinson anticipated to be an exceptionally effective explosive. In 8 months he managed to make 100 g of the compound but was then dispatched to the Research Department of Woolwich Arsenal, at that time evacuated to the University College at Swansea. There he spent most of his time in the library where he eventually found R. N. Keller s review on olefin metal complexes [3]. He remembered that Mann had mentioned in his lectures that olefins were the only ligating species that did not possess a lone pair of electrons, which prompted him to work on their complexes as soon as he was free to do so. 

Andrew Loder, Benjamin M.Zeldes, Jonathan M. Conway, James A. Counts, Christopher T. Straub, Piyum A. Khatibi, Laura L. Lee, Nicholas P. Vitko, Matthew 14 Keller, Amanda M. Rhaesa, GabeM. Rubinstein, IsraelM. Scott, Gina L. Lipscomb, Michael W.W. Adams, and RobertM. Kelly... 

Chain folded lamellar crystals were described early 1950 by Prof. Andrew Keller who recognised that in flexible macromolecules the thermodynamically most favourable conformation is a chain folded lamellar crystal. The figure gives the SEM photo and a drawing of his model. 

Strained and unstrained films of natural rubber were examined by Andrews [bS, 66] who showed that the spherulitic morphology of the unstrained films changes to a fibrillar morphology with crystalline units on the order of 6 25 nm wide. This is consistent with the work of Scott [18] who showed that strain-induced crystallinity results in fibrillar structures parallel to the strain direction. A further development of this idea by Keller and Machin [62] showed the morphology of melt extruded PE sheets to be an arrangement of lamellar crystals, normal to the stress direction, arranged in fibrillar units parallel to that stress. The concept of model film studies providing information related to commercially produced materials was described in this study. 

The experimental work originated from an EPSRC ROPA grant to Professor RJ Young and AIR at UMIST. The theoretical support of Peter Olmsted, Wilson Poon and Tom Mcleish is most appreciated. The constructive critism of Frank Bates, John Blackwell, Gerhard Eder, Julia Hi ins, Ben Hsiao, Andrew Keller (now sadty deceased), Herve Marand, Paul Phillips, Gert Strobi and an anonymous referee are most appreciated. 

Andrew Keller entered the H. H. Wills Physics Laboratory in 1955 and was stunned by what he saw ... 

It was perhaps Andrew Keller who introduced the hierarchical morphological scheme starting with the lamellar (folded-chain) crystal as the fundamental unit of the lamellar stacks, which in turn build up the various supermolecular structures, of which the spherulite is the most prominent member. These superstructures are polycrystalline. They consist of a great many lamellar crystals and also many lamellar stacks. This section briefly presents the experimental techniques useful in the assessment of supermolecular structures. 

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