Remarks on the Structure and Properties of High Polymers

CONCLUDING REMARKS ON THE STRUCTURE AND PROPERTIES OF HIGH POLYMERS 

Other properties such as solubility, viscosity (above Tg and T ), modulus of elasticity, and strength are highly dependent on the polymer architecture, or pattern of the interconnections between units. In other words, these properties vary to a marked degree with changes in the molecular weight and in the degree of cross-linking. 

It is instructive to consider what steps may be taken to ascertain qualitatively the structural type and physical state of a given polymeric substance. To this end one should first of all determine whether or not the substance is soluble without decomposition in any solvent, 

If the polymer is hard, insoluble, and infusible without decomposition, and if it refuses to swell greatly in any solvent, it may be assumed either that it is highly crystalline, with a melting point above its decomposition temperature, or that it possesses a closely interconnected network structure (e.g., as in a highly reacted glyceryl phthalate or a phenol-formaldehyde polymer). Differentiation between these possibilities is feasible on the basis of X-ray diffraction. 

See chapter entitled Vulcanization by E. H. Farmer in Advances in Colloid Science (Interscience Publishers, New York), II (1946), 299. 

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