Zur Charakterisierung der Reaktionsprodukte bei der Umsetzung höhermolekularer ungesättigter Fettsäureester mit Schwefelwasserstoff bei Anwesenheit von elementarem Schwefel
✍ Scribed by Härtel, G. ;Pickel, K. H.
- Publisher
- John Wiley and Sons
- Year
- 1984
- Weight
- 375 KB
- Volume
- 86
- Category
- Article
- ISSN
- 0931-5985
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✦ Synopsis
In Fig. 9 the crystallization pattern at slow cooling is showed for some simple triglycerides. In the case of trimyristin, the a-form might exist and then be transformed directly to the 0' I. For trilaurin, however, it is obvious that the a-form does not exist before the crystallization in the p' ,-form. Since trilaurin crystallizes 15' C above its a-melting point the chain mobility is so high that the p' + p transition occurs at 2 1' C instead of the p'-form being stable. The reason why tristearin crystallizes in the cr-form under these conditions can be due to the lower probability that a long chain should develop alltrans. By holding isothedcally a tristearin melt in the undercooled regionabove thea-meltingpoint,e.g.at 60OCinorder
TEMP ("C)
to increase the probability for crystallization, the p-form is developed directly within 38 minutes.
A technical fat, to be used in the margarine production, is plastic. It consists of a mixture of various triglycerides. Some of these triglycerides have a melting point that is very high. If the time in the undercooled region is long enough these high melting triglycerides could segregate and crystallize directly in the 0-form as small crystallites, which can influence the crystallization of the entire fat.