The author describes a novel method of preparing hydrolysis-stable non-silicate glasses which is based on experimental work accomplished over the past twenty years. As such, the method is the beginning of a new approach to glass-making by the use of a molecularly-polymerizable precursor.
The book elucidates the technical details required to produce such molecularly-polymerized glasses from carefully prepared inorganic molecular monomers. Essentially, only silicate-based glasses have been known to be stable, whereas non-silicate glasses could not be attributed with such properties. Such glasses have, therefore, not found widespread usage in industry. The new phosphate glasses described here exhibit stabilities superior to many of the silicate glasses. For example, the nuclear-waste glass shows no measurable loss at all in boiling water, something entirely foreign to the zinc borosilicate glasses developed for nuclear waste encapsulation in the U.S. by Battelle-Northwest.
The exceptional stability of the new glasses is achieved by selecting an inorganic compound capable of being polymerized, and then causing it to polymerize in a proper manner, in the absence of chain-stoppers. To obtain glasses equal or superior in hydrolysis stability to silicate-based systems it is imperative to employ molecular polymerization in situ, starting from carefully prepared precursors of exact stoichiometric proportion.
Researchers in glass and glass properties will find this volume extremely useful and those involved in organic polymers will be intrigued by the similarities and disparities of the two systems.
1. Introduction to Silicate Glass Technology. Glass and Antiquity. The Glassy or Vitreous State. Glass Formers and Glass Compositions. The Manufacture of Silicate-Based Glasses. Forming and Finishing Operations. Thermal Processing and Properties of Silicate Glasses. Inherent Properties of Glass. Silicate Glass Products Currently being Manufactured. 2. Introduction to Polymeric Glasses. Prior Attempts to Prepare Stable Phosphate Glasses. Structural Units in Glass. Basis for Chain Structure of Polymerized Phosphates. Prior Attempts to Prepare Phosphate Glasses by the Melting of Stoichiometric Compounds. Crystalline Salt Monomers for Stable Phosphate Glass Preparation. 3. Factors Contributing to the Preparation of Stable Phosphate Glasses. Anomalous Recrystallization of Polymeric Calcium Phosphate Glass. Abnormal Strain Relief Behavior of Polymeric [Ca(PO3)2]n Glass. The Effect of Melt Hold Time on Glass Points. Measurement of Hydrolysis Stability of Polymerized Glasses. Effects of Purity and Melt Hold Time on Hydrolysis Stability of Polymerized Glasses. Effect of Melt Hold Time on Melt Viscosity. Effect of Excess H3PO4 on the Reaction Paths of Monobasic Salts. Effect of Ca/P Ratios on Stability of Polymerized Glass Compositions. Other Polymerized Alkaline Earth Phosphate Glasses. Effect of Crucibles Used to Hold the Melt during Polymerization. The Combined Effects of Purity and MHT upon Polymerization. 4. Further Aspects of Polymerized Phosphate Glasses. The Impurity Phase-Segregation Phenomenon. Phase Separation as a Function of M in [CaM(PO3)2]n Glass. Physical Properties of Fully Polymerized Phosphate Glasses. Elimination of Striae and Other Optical Defects. Spectral Properties and Ultraviolet Transparency. Internal Diffusion Mechanisms and Modes of Chemical Attack. Optimal Methods of Purification. Other
- © Elsevier Science 1992
- 11th May 1992
- Elsevier Science
- eBook ISBN:
- Hardcover ISBN:
Richard C. Ropp, Ph.D., holds a Ph.D. in Physical Chemistry from Rutgers University (1971), an M.S. from Purdue University (1952), and the A.B. (Chem.) from Franklin College (IN). His career in chemistry spans over 60 years and he has been a consultant to industry during the past 40 years. Dr. Ropp has presented many seminars and talks and is the author of eight books (six by Elsevier). These books are based upon the properties of alkaline earth compounds. He began working with alkaline earth compounds in 1952, and was the originator and inventor of the red color TV phosphor in 1956 which is still being used today. He also created more than 25 new lamp and TV phosphors still being manufactured for the industry. Most of these were based upon alkaline earth compounds. He also developed more than 15 new chemical processes for raw materials used in the trade, many of which involved the manufacture of alkaline earth compounds. Fifty-five patents have been issued in his name (seven on glass) and he has published 63 technical papers. About 90% of the patents involved alkaline earth compounds. He is the inventor of a new type of alkaline earth phosphate glasses based on molecular polymerization. These glasses do not exhibit surface leaching by water and are more stable to hydrolysis than silicate-based glasses. These new glasses have unique applications in fiber-optics, high level nuclear waste disposal, high strength fibers, medical and dental implants, lasers, projection TV, and uses in optical and electronic components. Dr. Ropp held appointments as Research Specialist and Member of the Faculty of the Department of Chemistry at Rutgers University in Newark, NJ from 1971 to 1981. His experience has been varied and he has acted as Consultant and Expert Witness to attorneys concerning the technological aspects of their ongoing cases from 1989 to 2011 (more than 155 cases). From January 1990 to January 17, 1991, he served as Vice President of Technology for International
FRSC, FAIC &BCFE, Warren, New Jersey, USA
@qu:The excellent layout makes the text quick and easy to assimilate. @source:Angewandte Chemie