Vegetable oils chemical modification

Chemical modification of the wax can improve smear resistance (5). Sihcones, which do not harm furniture finishes (6), are incorporated as film-forming ingredients in furniture pohshes. The lubricant properties of sihcones improve ease of apphcation of the pohsh and removal of insoluble soil particles. In addition, sihcones make dry films easier to buff and more water-repeUent, and provide depth of gloss, ie, abihty to reflect a coherent image as a result of a high refractive index (7). Wax-free pohshes, which have sihcones as the only film former, can be formulated to dehver smear resistance (8). Another type of film former commonly used in oil-base furniture pohshes is a mineral or vegetable oil, eg, linseed oil. 

All of the studies were conducted with weanling, male albino rats of the Sprague-Dawley strain (Holtzman company). The basal diet used for these studies consisted of casein, starch, vegetable oil, vitamin and mineral mixtures, and cellulose. The Wesson Modification of the Osborne-Mendel mineral mixture was used in all studies. This mineral mixture contained no zinc, but it was adequate in the other minerals required by the rat. Most of the non-zinc-supplemented diets used in the various experiments contained approximately 7 ppm zinc. The level of mineral mixture used in the basal diets was 4%, and based on the chemical composition of the mixture, the basal diets contained approximately 0.57% calcium and 0.41% phosphorus ... 

Biodiesel (fatty acid methyl ester (FAME)) production is based on transesterification of vegetable oils and fats through the addition of methanol (or other alcohols) and a catalyst, giving glycerol as a by-product (which can be used for cosmetics, medicines and food). Oil-seed crops include rapeseeds, sunflower seeds, soy beans and palm oil seeds, from which the oil is extracted chemically or mechanically. Biodiesel can be used in 5%-20% blends with conventional diesel, or even in pure form, which requires slight modifications in the vehicle. 

Edible fats and/or oils, or mixtures of these, whose origin is vegetable or rendered animal carcass fats or any form of oil from a marine species that has been affirmed as GRAS or listed as a food additive for this use, any or all of which may have been subjected to an accepted process of physico-chemical modification. They may contain small amounts of other lipids such as phosphatides, or unsaponifiable constituents and of free fatty acids naturally present in the fat or oil. 

Current research efforts are directed toward improving the thermal and low-temperature stability of vegetable oils by chemical modification, blending with functional fluids and additive response studies. 

The pressure for increased use of vegetable oils in lubricants, due to environmental as well as health and safety considerations, is likely to continue. New genetic varieties, commercialisation of existing varieties, together with new chemical modifications will increase the types of materials available. Economic trends are likely... 

Vegetable oils are an excellent renewable source of raw materials for the manufacture of polyurethane components, such as polyols hence, the chemical modification or the transformation of the double bonds of triglycerides of oils to hydroxyl moieties and their applications in polyurethanes has been the subject of many studies. The main technological advantages of these polyurethanes from vegetable oils are their high strength and... 

The understanding of the mechanisms involved in the polymer synthesis with natural precursors is definitively a key factor for their appropriate exploitation. Taking into account this need, Ronda et al. explained recently different pathways to modify natural resources. These authors proposed three routes to modify vegetable oils to transform them into polymers (1) direct polymerization (cationic, radical, or thermal polymerization) (2) functionalization and polymerization and (3) monomer synthesized, chemical modification and polymerization [32]. 

Most contributions to the preparation of macromolecular materials derived from vegetable oils involve at least a modicum of chemical transformation, if not major modifications. The pancity of studies associated with their direct exploitation is due to the intrinsic mechanistic limitations of these pristine structures (with the possible exception of castor oil and ricinoleic acid) in terms of constructing as wide a variety of materials as required by the vast array of polymer applications. 

Acyclic triene metathesis (ATMET) polymerisation is a particular ADMET application useful in vegetable oils. ADMET can also be used for the polymerisation of triglycerides, offering the possibility to obtain branched polymers directly from plant oils without prior chemical modification, thereby helping to further minimise the environmental impact of snch materials. This type of polymerisation was termed ATMET with reference to monomer functionality [51]. 

Fatty acids are the major chemical entities present in vegetable oils. They are valuable compounds to design specific monomers in the search of polymers with particular properties without any need of important modifications in their native structure. This is an advantageous issue, not only in sustainability terms, but also in industrial applicability and competitiveness in terms of cost and properties [2-5]. 

Most naturally occurring vegetable oils contain a triacylglyceride structure, as shown in fig. 15.1. This structure [5, 59] has been described as a tuning fork and is a good lubricant, even without any chemical modification [22, 28]. Additionally, the fatty acid chains on the oil itself can become an oleochemical thickener. During manufacture, the appropriate metal cation and a base are added to the mixture, and glycerol is removed, as shown in fig. 15.3. 

Turunc O, Meier MA (2010) Fatty acid derived monomers and related polymers via thiol-ene (Click) additions. Macromol Rapid Commun 31 1822-1826 Vaidya R (2012) International conference on environmental. Biomed Biotech 41 55 Wang L, Wang T (2007) Chemical modification of partially hydrogenated vegetable oil to improve its functional properties for candles. J American Oil Chem Soc 84 1149-1159... 

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