Morphology observations additives

Crystallization from the melt often leads to a distinct (usually lamellar) structure, with a different periodicity from the melt. Crystallization from solution can lead to non-lamellar crystalline structures, although these may often be trapped non-equilibrium morphologies. In addition to the formation of extended or folded chains, crystallization may also lead to gross orientational changes of chains. For example, chain folding with stems parallel to the lamellar interface has been observed for block copolymers containing poly(ethylene), whilst tilted structures may be formed by other crystalline block copolymers. The kinetics of crystallization have been studied in some detail, and appear to be largely similar to the crystallization dynamics of homopolymers. 

Generally, the friction coefficient decreases as the load of filler increases but there is a critical quantity above which the friction coefficient decreases. The correct amount of anti-wear additive for a particular material and a particular applied load can be determined by simple morphological observation of the surface. The expected wear pattern forms surface debris whereas if the part is not wearing well its surface will melt and become shiny. 

Furthermore, with PES5003P, xcp 0.40 and the particles are also smaller than with NFBN. We also see an effect of the viscosity and of the reactive chain ends of the thermoplastic. But because is 180 °C, which is lower than the Tg of the thermoplastic, one important effect is certainly also the vitrification of the dispersed particles when phase separation occurs. The consequence is that only with thermoplastic additives is an evolution of the morphology observed between precuring and postcuring processes. 

Crystalhzation studies in blends of iPP/POE reveal that the crystallization process of iPP is affected by the addition of POE and vice versa. It has been demonstrated how the POE promotes the nucleation and crystal growth processes of iPP, this effect being more appreciable at low POE concentration (< 10 wt% POE). Analysis of the crystallization kinetics of the iPP crystals isothermally crystallized at different temperatures in blends of iPP/POE is supported by the morphological observations (lamellae, dendritic, and eventually spherulitic texmres) through optical microscopy. 

Water (6 8 wl%) At higher degrees of hydrolysis of 98% gap distance observed to have no significant effect on the fiber morphology. The additions of sodium chloride and ethanol found to have significant effects on the fiber morphology. 

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