CONTENTS 5 Crystal engineering

Figure 4.11 The influence of comonomer content and type on the crystallization half-time of PET [51]. Reproduced from Sakellarides, S. L., ANTEC, 96, 938-942 (1996), with permission from the Society of Petroleum Engineers...

The exact temperature at which the cloud point is reached depends on the total n-alkane content of the fuel, the average size of the n-alkane molecules, their size distribution and chain structure (e.g. degree of branching). Conventional diesels contain as much as 20% of long-chain n-alkanes of limited solubility in the fuel. Pyrolysis-diesels from PE feedstocks can contain more than 40% long-chain n-alkanes. Paraffins crystallize at low temperature into very thin rhombic plates which can clog filters, transfer lines, and pumps, and can lead to engine failure at low temperatures. 

As shown in Table 5, Ky and A change rather insignificantly on introduction of kerogene into polyethylene. We can consider, with accuracy sufficient for engineering practice, that the crystallization kinetics of PE keroplasts do not depend on the content of filler in polyethylene. In Fig. 2 we demonstrate the good correlation of theoretical calculations with the experiment. 

The time to develop new high temperature single crystal nickel-hased superalloys with low rhenium content was reduced hy more than 50 percent (see R. Schafrik, Accelerating materials and process development. International Association of Air Breathing Engines, ISABE2009 paper ISABE-2009-1167, September 2009). 

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