noying, especially in a fairly expensive book, to find that the review copy had printing defects on several pages, where multiple printing had produced shadow characters making the text difficult to read.

Although the material in this book by Halgas is not especially up-to-date, its particular strength lies in providing a comprehensive and detailed account of enzymic methods in organic synthesis. Thus it is suitable both as an introduction to preparative biocatalysis and as a per- manent reference source for research chemists and lecturers with interests in this field.

WoljlDieter Fessner Institut fur Organische Chemie

und Biochemie der Universitit Freiburg (FRG)

Liquid Crystal Polymers. (Series : Speciality Polymers. Series editor: J. M . C. Con'ie.) Edited by N . A . Plat&. Plenum, New York, 1993. 438 pp., hardcover $ 110.00.-ISBN 0-306-4421 9-1

This book consists of ten chapters in which twelve Russian authors summarize the rapid developments that have oc- curred in the field of liquid crystal poly- mers in the last 15 years or so. Especially noteworthy is the very good coordination that has been achieved between the vari- ous specialists with regard to content, consistcnt use of symbols, and form of presentation. Each chapter has a short in- troduction linking it to the other authors' contributions and briefly describing the historical development. On the whole the editor has succeeded well in ensuring that the individual authors' reviews of pro- gress in liquid crystal polymers are highly informative and critically presented. It is entirelb appropriate that in this area of research the Russian literature should be given special emphasis, as much of it is not sufficiently well known in other countries. However, it must be noted less favorably that there are only sporadic references to work published from 1987 onwards. Brief descriptions of the ten chapters follow.

Chapter 1 : Statistical physics of liquid crystalline order in polymeric systems (A. R. Khoklov, 38 pp.. 139 refs.). Theo- retical models for both rigid and flexible polymers are critically discussed with ref- erences to the original papers. Melting be- havior and elastic and rheological proper- ties are treated in rather more detail. This chapter provides the fundamental basis for the following chapters. Chapter 2:

Phase equilibria in polymer systems with liquid crystalline phases (S. P. Papkov, 32 pp., 58 refs.). After a general classifica- tion of the types of phases and explana- tions of the meaning of thermotropic and lyotropic phases. the author concentrates mainly on the solution behavior of poly- mers with rigid chains. The predictions of several different models are compared. Chapter 3: Molecular structures of poly- mers with mesogenic groups (I. N. Shten- nikova, 54 pp., 11 1 refs.). Different con- formations are discussed, and the implica- tions in relation to streaming birefring- ence and the Kerr effect are briefly con- sidered. This is followed by a discussion of these effects as observed in lyotropic poly- mers and in polymers with main and side chains, from the standpoints of different theories. Chapter 4: The mesomorphic state of polymers with flexible chains (Yu.K. Godovskii and V.S. Papkov, 38 pp., 93 refs.). Various experimental re- sults on linear polyorganosiloxanes, poly- phosphazenes, and cyclolinear poly- organosiloxanes are summarized and evaluated. Chapter 5: Thermotropic liq- uid crystal polymers with mesogenic groups in the main chain (S. S. Sko- rokhodov, 30 pp.. 82 refs.). Continuing the theme of Chapter4, syntheses of polyesters, polyethers, and polyurethanes are described. Special attention is devoted to the use of texture observations to rec- ognize the liquid-crystalline state, and to the detection of order. The effects of the previous history of the polymer on its physico-chemical properties are dis- cussed. Chapter 6: Comb-like liquid crys- tal polymers (V. P. Shibaev, 57 pp., 69 refs.). V. P. Shibaev, one of the 'fa- thers' of polymers with liquid-crystalline side chains, discusses some of his areas of research: methods for the synthesis of polyacrylates. polymethacrylates, poly- esters, and polypeptides with various liq- uid-crystalline side groups. Topics receiv- ing special attention are the glass transi- tions of the polymers, and related discussions regarding the thermal equi- librium, the effects of chemical variations (including the degree of polymerization) on phase transition temperatures, struc- tural aspects of the phases. and ferroelec- tric polymers. The survey of nematic poly- mers and the comparison with smectic polymers in this chapter are some of the most valuable sections of the book. Un- fortunately it has only been possible to give a hint here of the start of the rapid developments in the field of elastomers that have occurred in the last few years. Chapter 7: Liquid crystal polymers of the cholesteric type (Ya. S. Freidzon and V. P. Shibaev, 52 pp., 87 refs.). By limiting the

topic area to be covered, the authors have been able to give a detailed and compre- hensive treatment which is well worth reading, even by specialists. Chapter 8: Structural transformations of thermo- tropic liquid crystal polymers in electric and magnetic fields (R. V. Talroze and N. A. Plate, 36 pp., 67 refs.). Starting from the fundamental principles, the au- thors deal mainly with electrooptical ef- fects of dielectric and hydrodynamic orig- in, and with induced phase transforma- tions and memory effects (information storage). This section should be especially useful to technologists with interests in this area. Chapter 9: Rheological proper- ties of liquid crystal polymers (B. G. Kulichikhin, 44 pp., 119 refs.). The theo- retical and experimental aspects of poly- mer solutions and melts are treated com- prehensively. The author also briefly discusses some hitherto unsolved experi- mental problems and potential technolog- ical applications. Chapter 10: High- strength and high-modulus fibers from liquid crystal polymers (A. V. Volokhina and G. I. Kudryavtsev, 36 pp.. 94 refs.). The authors discuss the technology and characterization of Aramid fibers, ultra- high-modulus fibers made from hetero- cyclic monomers, and lyotropic polymers. and predict a bright future for such niate- rials.

The book can be recommended for ev- eryone with interests in mesomorphic phases, and for those concerned with new developments in electrooptics, informa- tion storage, sensor technology. and fibers research.

tforst Kresse Institut fur Physikalische Chemie

der Universitat Halle-Wittenberg (FRG)

Chirotechnology. Industrial Synthesis of Optically Active Compounds. By R. A . Slieldon. Marcel Dekker, New York, 1993. 423 pp., hardcover $ 145.00-ISBN 0-8247-9143-6

Does stereochemistry have any particu- lar implications for the design of an indus- trial chemical process, and if so, what methodologies with scale-up potential are available for efficient and successful man- ufacturing of stereoisomers? This simple and straightforward two-fold question well reflects the tremendously increased impor- tance and awareness of industrially related stereochemical issues over the past one or two decades. The three-dimensional con- cept of molecular species so brilliantly con- ceived in the mid-1870s and assuming a central role ever since, especially in organic