Premium
Growth, morphology, and reinforcement potential of low molecular weight crystals in amorphous polymeric matrices
Author(s) -
Joseph Jacques R.,
Kardos John L.,
Nielsen Lawrence E.
Publication year - 1968
Publication title -
journal of applied polymer science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.575
H-Index - 166
eISSN - 1097-4628
pISSN - 0021-8995
DOI - 10.1002/app.1968.070120514
Subject(s) - materials science , crystallization , amorphous solid , polymer , chemical engineering , supercooling , crystal (programming language) , copolymer , polymer chemistry , phase (matter) , composite material , crystallography , thermodynamics , chemistry , organic chemistry , programming language , physics , computer science , engineering
The technique of in situ crystallization of low molecular weight organic compounds from amorphous polymers was evaluated as a method of fabricating composite materials. Two workable systems, styrene–acrylonitrile copolymer (SAN)–acetanilide and SAN–anthracene, were found and their phase diagrams determined. In both systems kinetic studies revealed that the maximum crystallization rate takes place at large degrees of supercooling and that below these temperatures the mechanism is diffusion‐controlled. The temperature‐dependent crystal morphologies were characterized with electron microscopy, which showed three distinctly different morphologies for both systems. From dynamic mechanical measurements, it appears that the elastic moduli of organic crystals are about the same as those of organic polymers in the glassy state, and that relatively little reinforcement took place under the particular crystallization conditions employed.