Crystallization retardants

Cold flow properties are of major importance in winter diesel. Cold performance limits are set to guarantee lack of crystallization. These are expressed as Cloud Point (CP), Pour Point (PP), or as Cold Filter Plugging Point (CFPP). For B100 biodiesel these have to be fully met with the biodiesel, and, if needed, with extra crystal retardation additives. In B2-B30 blends, though, the tendency is rather towards two types of Biodiesel, one for summertime (for example with CFPP of 0°C), and one for wintertime (for example with CFPP -10 °C). 

Due to the difference of the polymer adsorption onto different faces of different crystal forms, polymer adsorption onto the crystal face has played an important role in crystal polymorphic transformationJ Garti and Zour have studied the effects of surfactants on the polymorphic transformation of glutamic acid. Glutamic acid has two crystal forms, a and p, with the p-form being more stable than the ot-form. Those surfactants that preferentially adsorb onto the surface of the ot-growing crystals retard the transformation of the ot-form to the p-form. A Langmuir analysis indicates that the kinetic coefficient of crystal polymorphic transformation is related to the volume of the surfactant adsorbed at the crystal surface. 

In a typical Lyot filter, crystals are often selected so that transmission has its maximum value at the wavelength determined by the thickest crystal retarder, with... 

KoIUdon . [BASF AG] PVP solubilizer, crystallization retarder, stabilizer for andbiodc suspensions bindos for tablets, dispersants. 

Molded articles, in particular containers, such as bottles and jars, made from the polyester resin copolymers can be manufactured by using melt molding methods. Containers and bottles can be manufactured without the necessity of adding crystallization accelerators or crystallization retardants. The materials have low levels of acetaldehyde. ... 

Uses Emulsifier, solubilizer for foods, cosmetics, household prods., industrial applies., coatings, household (polishes, cleaners), pharmaceuticals lubricanL antifog, antistat for PVC and other plastics antifog for food-pkg. films emulsifier for thermoplastics polymerization emulsifier in food pkg. emollient for skin care prods. lubricant, emulsifier in textile spin finishes cosolvent foods (crystallization retarder, dough improver)... 

The results of Muller et al. [103] on PPDX-fo-PCL diblock copolymers differ from those obtained previously by Bogdanov et al. [105] when they studied by DSC the crystallization kinetics of 80/20 PCL-fo-PEO diblock copolymers. In their case, the PCL block crystallized first from a homogeneous melt and the Avrami parameters K and n were found to be similar to the kinetics parameters of the isothermal crystallization of a corresponding PCL homopolymer. Significant crystallization retardation was found for the PEG block that crystallized second. The retardation was attributed to the mutual influence between the PEG constituent and the PCL crystal phase which fixes (hardened) the total copolymer structure [ 105]. In the PPDX-fo-PCL diblock copolymer case, conversely, when the PPDX block crystallizes it does so at a slower rate than a comparable PPDX homopolymer. The crystallization of the PCL block, on the other hand, strongly depends on the composition of the diblock copolymer as shown in Fig. 9. However, for D77 C23 , the overall kinetics is retarded, which could be regarded as similar to the retardation experienced by the PEG block in the 80/20 PCL-fi-PEG diblock copolymer studied by Bogdanov et al. [105] the Avrami index in both cases was also of the order of 2. 

In a typical Lyot filter, crystals are often selected so that transmission has its maximum value at the wavelength determined by the thickest crystal retarder, with other stages in the filter serving to block the transmission of unwanted wavelengths. The spectral region passed by the LCTF is dependent on the choice of polarizer, optical coating, and the liquid crystal characteristics (nematic, cholesteric, smectic, etc.). In practice, a Lyot LCTF may have as many as 11 polarizers and 10 liquid crystalline layers and is sometimes equipped with an internal microprocessor to tune all of the stages. 

Uses Emulsifier for foods, baked goods, dairy prods., edible oils/shortenings, confectionery volume improver, texturizer in cakes emulsion stabilizer in margarine crystallization retarder in starch jellies improves palatability and rehydration in dehydrated potatoes fat separation retarder, moisture retention aid, and extrusion aid in petfoods... 

Uses Raw material for lubricants oiliness agent for lubricants plastics lubricant and dispersant crystal retardant for flowable agric. formulations Properties YIsh. brn. liq. sol. in ethanol, n-hexane, xylene acid no. 2 max. Exceparl SS [Kao Corp.]... 

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