Showing papers by "Dean C. Webster published in 1985"
01 Jan 1985
TL;DR: In this paper, the authors presented a block copolymer composed of two blocks of styrene and one block of butadiene representing the soft segment, where the hard or glassy segment is below its glass transition temperature at the temperature of interest.
Abstract: The possible morphologies which can be obtained in a two component block or segmented copolymer are rubber-rubber, glass-rubber, crystalline-rubber, glass-glass, glass-crystalline, and crystalline-crystalline. The first three of these morphological combinations compose the vast majority of block or segmented copolymers synthesized. 1,2 Especially prevalent are the copolymers composed of glass-rubber morphologies. A typical example of such a copolymer based on “hard” and “soft” segments would be a styrene-butadiene-styrene (SBS) block copolymer.3 This copolymer is made up of two blocks of styrene, which comprise the “hard” segments, and one block of butadiene representing the “soft” segment. The “hard” or glassy segment is below its glass transition temperature at the temperature of interest, which is usually ambient temperature, while the “soft” or rubbery segment is above its glass transition temperature. Thus, this class of copolymers have become very important in the area of thermoplastic elastomers and related materials and have found commercial applicability in a wide range of products.
2 citations