Strontium myristate

Figure 4. The rod systems formed by the polar groups in the cubic phase that forms in strontium myristate (6)...

A cubic phase in soap-water systems was described in the work by Luzzati and co-workers (1960) in which the lattice was then assumed to be face-centred. Cubic phases were also observed in other lipid systems (cf. Clunie et aL, 1965). A structure consisting of water spheres in a hydrocarbon chain matrix was then proposed by Luzzati and Reiss-Husson (1966). Soon afterwards Luzzati and Spegt (1967) analysed the structure of the cubic phase of strontium myristate which was reported to consist of two networks of rods formed by the polar... 

Figure 8.10 Structure determined by Luzzati and Spegt (1967) in strontium myristate. The polar groups form two networks (indicated by full and broken lines respectively), and the disordered hydrocarbon chains fill the space in between.

This rod-system structure was considered to be the general structure for cubic lipid-water phases (Luzzati et al., 1968). Thus anhydrous strontium myristate, lecithin and galactolipids from maize chloroplasts with low water content were thought to have the structure shown in Fig. 8.10 with the polar groups arranged in two network systems of rods. The inverse structure, i.e. with hydrocarbon chains forming the rod systems and water forming the outer medium, was proposed to exist in aqueous systems of potassium soaps of lauric, myristic and palmitic acid and in aqueous systems of lauroyl- and palmitoyl-trimethylammonium bromide. 

Stilhella thermophile, 152 Stillingia oil, 11,13,52,53,58 see also Chinese vegetable tallow Stillingic acid, 11 Stillingia sebifera, 58 Storage, 183,189 Streptococcus species, 35, 47,157 Strontium myristate, 328 Strophanthus species, 19 Structural determination, 272, 282 Structure, 142,159, 321, 322, 327, 332, 339,382... 

Figure 16.35 (Plate 1). All strontium myristate. Top left lOOx crossed polars - room-temperature lamellar. Top right lOOx crossed polars 90°C - lamellar. Middle left lOOx crossed polars, gypsum plate in, heated to 218°C - rhombohedral. Middle right 200 x crossed polars, gypsum plate in, cooled from rhombohedral-cubic phase boundary, oscillated near 210-215°C - rhombohedral (bright) and cubic (dark). Bottom left lOOx parallel polars, cooled to 210 from 218°C - cubic to rhombohedral transition. Bottom right 200 x crossed polars, gypsum plate in, cooled from 290°C and oscillated near 260° C - hexagonal...

A soap is an aliphatic or aromatic carboxylate, such as a stearate, benzoate, oleate, palmitate or myristate. An appropriate combination of two metal soaps can give rise to very useful PVC stabiliser systems. One must be chosen from Group llA of the periodic table (magnesium, calcium, strontium, or barium) and one from Group IIB (theoretically zinc or cadmium, but in practice cadmium is no longer used in Europe and most other countries). 

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