TABLE OF CONTENTS Organic glasses consist of carbon-carbon chains which are so entangled that rapid cooling of the melt prevents reorientation into crystalline regions. These structures closely resemble those of vitreous sulfur and selenium, which also consist of entangled chains. The chains in organic glasses can also be crosslinked, just as they are in chalcogenide glasses, with consequent changes in their properties. Increasing the degree of crosslinking, for example, increases the viscosity of the melt and the glass transformation temperature. In general, the properties of organic glasses closely parallel those of the inorganic glasses with chain-based structures, including the ability to produce materials with oriented properties by application of stress during forming.
Small regions of oriented chains often exist in organic glasses, so that many of these materials actually resemble low-crystallinity glass-ceramics. Proper heat treatments can increase the crystallinity of many of these glasses. Properties of the partially crystalline materials follow the same trends with increasing crystallinity as observed for inorganic glass-ceramics.
