Morphology polymer spherulites

Fanta, G. F., Felker, F. C., Shogren, R. L., Saleh, J. H. (2006). Effect of fatty acid structure on the morphology of spherulites formed from jet cooked mixtures of fatty acids and defatted cornstarch. Carbohydrate Polymers, 66, 60-70. 

HMS can crystallize in either banded or nonbanded spherulitic morphologies as illustrated in Figures 2a and 2b respectively (14). Banding is typical of HMS crystallized below 56°C whereas nonbanded spherulites are formed by crystallization above 56°C (14). Banding of polymer spherulites is thought to be related to the periodic twisting of... 

Ultraviolet and fluorescent microscopy has been applied to a variety of polymer systems to investigate changes of morphology and composition on the scale of 0.25 ym upwards. Studies are briefly described on the behaviour of stabilisers in polypropylene, diffusion of additives in polymers, spherulite morphology, polyolefin oxidation, inhomogeneities in epoxy resins and polymer blends. 

Practical appHcations have been reported for PVP/ceUulosics (108,119,120) and PVP/polysulfones (121,122) in membrane separation technology, eg, in the manufacture of dialysis membranes. Electrically conductive polymers of polyaruline are rendered more soluble and hence easier to process by complexation with PVP (123). Addition of small amounts of PVP to nylon 66 and 610 causes significant morphological changes, resulting in fewer but more regular spherulites (124). 

Morphology. Observations with the light microscope, under polarized light, showed that the end blocks in the case of both types of polymers crystallized in the form of the usual spheru-lites, but not as well as the analogous homopolymer, H2-l,4-polybutadiene. The formation of the spherulites was improved with increasing end-block content and/or higher molecular weight of the end blocks. 

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