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89-479: Gels are mostly liquid by mass , yet they behave like solids because of a three-dimensional cross-linked network within the liquid. It is the cross-linking within the fluid that gives a gel its structure (hardness) and contributes to the adhesive stick ( tack ). In this way, gels are a dispersion of molecules of a liquid within a solid medium. The word gel was coined by 19th-century Scottish chemist Thomas Graham by clipping from gelatine . The process of forming

178-477: A direct fuel , as well as in the production of biodiesel , livestock feed , pet food, soap, detergent, cosmetics, and industrial chemicals. Since 2002, an increasing number of European Union countries have prohibited the inclusion of recycled vegetable oil from catering in animal feed. Used cooking oils from food manufacturing, however, as well as fresh or unused cooking oil, continue to be used in their animal feed. Due to their susceptibility to oxidation from

267-485: A German chemist, introduced the hydrogenation of liquid fats in 1901, creating what later became known as trans fats , leading to the development of the global production of margarine and vegetable shortening . In the United States, cottonseed oil was developed, and marketed by Procter & Gamble as a creamed shortening – Crisco – as early as 1911. Ginning mills were happy to have someone haul away

356-705: A cooking oil in Europe. It became highly sought-after commodity by British traders for use as an industrial lubricant for machinery during Britain's Industrial Revolution . Palm oil formed the basis of soap products, such as Lever Brothers' (now Unilever ) "Sunlight", and B. J. Johnson Company's (now Colgate-Palmolive ) "Palmolive," and by around 1870, palm oil constituted the primary export of some West African countries. In 1780, Carl Wilhelm Scheele demonstrated that fats were derived from glycerol. Thirty years later Michel Eugène Chevreul deduced that these fats were esters of fatty acids and glycerol. Wilhelm Normann ,

445-543: A degree of flexibility very similar to natural tissue, due to their significant water content. As responsive " smart materials ," hydrogels can encapsulate chemical systems which upon stimulation by external factors such as a change of pH may cause specific compounds such as glucose to be liberated to the environment, in most cases by a gel-sol transition to the liquid state. Chemomechanical polymers are mostly also hydrogels, which upon stimulation change their volume and can serve as actuators or sensors . The first appearance of

534-448: A deodorization stage that removes trace amounts of odors and flavors, and lightens the color of the oil. However, the process commonly results in higher levels of trans fatty acids and distillation of the oil's natural compounds. People can breathe in vegetable oil mist in the workplace. The U.S. Occupational Safety and Health Administration (OSHA) has set the legal limit ( permissible exposure limit ) for vegetable oil mist exposure in

623-547: A drug release matrix. A hydrogel is a network of polymer chains that are hydrophilic, sometimes found as a colloidal gel in which water is the dispersion medium. A three-dimensional solid results from the hydrophilic polymer chains being held together by cross-links. Because of the inherent cross-links, the structural integrity of the hydrogel network does not dissolve from the high concentration of water. Hydrogels are highly absorbent (they can contain over 90% water) natural or synthetic polymeric networks. Hydrogels also possess

712-698: A final volume of 100   mL of solution would be labeled as "1%" or "1% m/v" (mass/volume). This is incorrect because the unit "%" can only be used for dimensionless quantities. Instead, the concentration should simply be given in units of g/mL. Percent solution or percentage solution are thus terms best reserved for mass percent solutions (m/m, m%, or mass solute/mass total solution after mixing), or volume percent solutions (v/v, v%, or volume solute per volume of total solution after mixing). The very ambiguous terms percent solution and percentage solutions with no other qualifiers continue to occasionally be encountered. In thermal engineering , vapor quality

801-408: A free energy difference density. The form of f gel ( λ 1 , λ 2 , λ 3 ) {\displaystyle f_{\text{gel}}(\lambda _{1},\lambda _{2},\lambda _{3})} naturally assumes two contributions of radically different physical origins, one associated with the elastic deformation of the polymer network, and

890-460: A gel is called gelation . Gels consist of a solid three-dimensional network that spans the volume of a liquid medium and ensnares it through surface tension effects. This internal network structure may result from physical bonds such as polymer chain entanglements (see polymers ) (physical gels) or chemical bonds such as disulfide bonds (see thiomers ) (chemical gels), as well as crystallites or other junctions that remain intact within

979-851: A high flash point . Such oils include both the major cooking oils – soybean , rapeseed , canola , sunflower , safflower , peanut , cottonseed , etc. – and tropical oils, such as coconut , palm , and rice bran . The latter are particularly valued in Asian cultures for high-temperature cooking, because of their unusually high flash points. Vegetable oils are used as an ingredient or component in many manufactured products. Many vegetable oils are used to make soaps, skin products, candles, perfumes and other personal care and cosmetic products. Some oils are particularly suitable as drying oils , and are used in making paints and other wood treatment products. They are used in alkyd resin production. Dammar oil (a mixture of linseed oil and dammar resin), for example,

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1068-451: A non-toxic alternative to other solvents. Unsaturated vegetable oils can be transformed through partial or complete hydrogenation into oils of higher melting point, some of which, such as vegetable shortening , will remain solid at room temperature. Hydrogenating vegetable oil is done by raising a blend of vegetable oil and a metal catalyst, typically nickel, in near-vacuum to very high temperatures, and introducing hydrogen. This causes

1157-724: A part of human culture for millennia. Archaeological evidence shows that olives were turned into olive oil by 6000 BC and 4500 BC in present-day Israel . Pagnol, p. 19, says the 6th millennium in Jericho , but cites no source. In ancient Egypt, plant oils including cedar oil, cypress oil, and olive oil were used during the mummification process. Vegetable oils have been used as lighting fuel for lamps, cooking, medicine and lubrication. Palm oil has long been recognized in West and Central African countries, and European merchants trading with West Africa occasionally purchased palm oil for use as

1246-442: A polymer solution of concentration ϕ 0 {\displaystyle \phi _{0}} and volume V 0 {\displaystyle V_{0}} is mixed with a pure solvent of volume ( λ 1 λ 2 λ 3 − 1 ) V 0 {\displaystyle (\lambda _{1}\lambda _{2}\lambda _{3}-1)V_{0}} to become

1335-470: A relatively high concentration of H + {\displaystyle {\text{H}}^{+}} and salt cations inside the gel. But because the concentration of H + {\displaystyle {\text{H}}^{+}} is locally higher, it suppresses the further ionization of the acid sites. This phenomenon is the prediction of the classical Donnan theory. However, with electrostatic interactions, there are further complications to

1424-441: A sharp increase in palm oil . Many vegetable oils are consumed directly, or indirectly as ingredients in food – a role that they share with some animal fats , including butter , ghee , lard , and schmaltz . The oils serve a number of purposes in this role: Oils can be heated to temperatures significantly higher than the boiling point of water, 100 °C (212 °F), and used to fry foods . Oils for this purpose must have

1513-490: A solution with polymer concentration ϕ {\displaystyle \phi } and volume λ 1 λ 2 λ 3 V 0 {\displaystyle \lambda _{1}\lambda _{2}\lambda _{3}V_{0}} . The free energy density change in this mixing step is given as where on the right-hand side, the first term is the Flory–Huggins energy density of

1602-458: A solvent. The extracted oil can then be purified and, if required, refined or chemically altered. Oils can be removed via mechanical extraction, termed "crushing" or "pressing". This method is typically used to produce the more traditional oils (e.g., olive, coconut etc.), and it is preferred by most health-food customers in the United States and in Europe. There are several different types of mechanical extraction. Expeller pressing extraction

1691-461: A source of fuel readily available. Diesel's first engine ran on its own power for the first time in Augsburg , Germany, on 10 August 1893 on nothing but peanut oil . In remembrance of this event, 10 August has been declared "International Biodiesel Day". The first patent on Biodiesel was granted in 1937. Periodic petroleum shortages spurred research into vegetable oil as a diesel substitute during

1780-470: Is a "partially hydrogenated oil" (PHO). An oil may be hydrogenated to increase resistance to rancidity ( oxidation ) or to change its physical characteristics. As the degree of saturation is raised by full or partial hydrogenation, the oil's viscosity and melting point increase. While full hydrogenation produces largely saturated fatty acids, partial hydrogenation results in the transformation of unsaturated cis fatty acids to unsaturated trans fatty acids in

1869-469: Is a solid formed from a gel by drying with unhindered shrinkage. Xerogels usually retain high porosity (15–50%) and enormous surface area (150–900 m/g), along with very small pore size (1–10 nm). When solvent removal occurs under supercritical conditions, the network does not shrink and a highly porous, low-density material known as an aerogel is produced. Heat treatment of a xerogel at elevated temperature produces viscous sintering (shrinkage of

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1958-521: Is by far the highest yielding crop, capable of producing about 4 tons of palm oil per hectare per year. The following triglyceride vegetable oils account for almost all worldwide production, by volume. All are used as both cooking oils and as SVO or to make biodiesel. According to the USDA, the total world consumption of major vegetable oils in 2007/08 was: These figures include industrial and animal feed use. The majority of European rapeseed oil production

2047-592: Is common, though the screw press , ram press , and ghani (powered mortar and pestle ) are also used. Oilseed presses are commonly used in developing countries, among people for whom other extraction methods would be prohibitively expensive; the ghani is primarily used in India. The amount of oil extracted using these methods varies widely, as shown in the following table for extracting mowrah butter in India: The processing of vegetable oil in commercial applications

2136-433: Is commonly done by chemical extraction, using solvent extracts, which produces higher yields and is quicker and less expensive. The most common solvent is petroleum-derived hexane . This technique is used for most of the "newer" industrial oils such as soybean and corn oils. After extraction, the solvent is evaporated out by heating the mixture to about 149 °C (300 °F). Supercritical carbon dioxide can be used as

2225-480: Is extruded around it. Mass fraction (chemistry) In chemistry , the mass fraction of a substance within a mixture is the ratio w i {\displaystyle w_{i}} (alternatively denoted Y i {\displaystyle Y_{i}} ) of the mass m i {\displaystyle m_{i}} of that substance to the total mass m tot {\displaystyle m_{\text{tot}}} of

2314-462: Is growing and the availability of biodiesel around the world is increasing. The NNFCC estimates that the total net greenhouse gas savings when using vegetable oils in place of fossil fuel-based alternatives for fuel production, range from 18 to 100%. The production process of vegetable oil involves the removal of oil from plant components, typically seeds. This can be done via mechanical extraction using an oil mill or chemical extraction using

2403-399: Is high both elastically and electrostatically and hence suppress ionization. Even though this ionization suppression is qualitatively similar to that of Donnan prediction, it is absent without electrostatic consideration and present irrespective of ion partitioning. The combination of both effects as well as gel elasticity determines the volume of the gel at equilibrium. Due to the complexity of

2492-419: Is initially formed by the assembly of particles into a space-spanning network, leading to a phase arrest. In the aging phase, the particles slowly rearrange to form thicker strands, increasing the elasticity of the material. Gels can also be collapsed and separated by external fields such as gravity. Colloidal gels show linear response rheology at low amplitudes. These materials have been explored as candidates for

2581-436: Is just a polymer network, without solvent). This is so because the free energy penalty to stretch an ideal polymer segment N {\displaystyle N} monomers of size b {\displaystyle b} between crosslinks to an end-to-end distance R {\displaystyle R} is approximately given by This is the origin of both gel and rubber elasticity . But one key difference

2670-513: Is like that from above substituting the relation between mass and molar concentration: where c i {\displaystyle c_{i}} is the molar concentration, and M i {\displaystyle M_{i}} is the molar mass of the component i {\displaystyle i} . Mass percentage is defined as the mass fraction multiplied by 100. The mole fraction x i {\displaystyle x_{i}} can be calculated using

2759-783: Is monomer volume, N {\displaystyle N} is polymer strand length and χ {\displaystyle \chi } is the Flory-Huggins energy parameter. Because in a network, the polymer length is effectively infinite, we can take the limit N → ∞ {\displaystyle N\to \infty } and f ( ϕ ) {\displaystyle f(\phi )} reduces to Substitution of this expression into f mix ( λ 1 , λ 2 , λ 3 ) {\displaystyle f_{\text{mix}}(\lambda _{1},\lambda _{2},\lambda _{3})} and addition of

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2848-399: Is one way of expressing the composition of a mixture in a dimensionless size ; mole fraction (percentage by moles , mol%) and volume fraction ( percentage by volume , vol%) are others. When the prevalences of interest are those of individual chemical elements , rather than of compounds or other substances, the term mass fraction can also refer to the ratio of the mass of an element to

2937-450: Is only partially by the classical Donnan theory. As a starting point we can neglect the electrostatic interactions among ions. Then at equilibrium, some of the weak acid sites in the gel would dissociate to form A − {\displaystyle {\text{A}}^{-}} that electrostatically attracts positive charged H + {\displaystyle {\text{H}}^{+}} and salt cations leading to

3026-441: Is polymer volume fraction. Suppose the initial gel has a polymer volume fraction of ϕ 0 {\displaystyle \phi _{0}} , the polymer volume fraction after swelling would be ϕ = ϕ 0 / λ 1 λ 2 λ 3 {\displaystyle \phi =\phi _{0}/\lambda _{1}\lambda _{2}\lambda _{3}} since

3115-421: Is stretch by a factor of λ {\displaystyle \lambda } in all three directions. Under the affine network approximation, the mean-square end-to-end distance in the gel increases from initial R 0 2 {\displaystyle R_{0}^{2}} to ( λ R 0 ) 2 {\displaystyle (\lambda R_{0})^{2}} and

3204-474: Is stretched by factors λ 1 {\displaystyle \lambda _{1}} , λ 2 {\displaystyle \lambda _{2}} and λ 3 {\displaystyle \lambda _{3}} in the three orthogonal directions during swelling after being immersed in a solvent phase of initial volume V s 0 {\displaystyle V_{s0}} . The final deformed volume of gel

3293-411: Is that gel contains an additional solvent phase and hence is capable of having significant volume changes under deformation by taking in and out solvent. For example, a gel could swell to several times its initial volume after being immersed in a solvent after equilibrium is reached. This is the phenomenon of gel swelling. On the contrary, if we take the swollen gel out and allow the solvent to evaporate,

3382-424: Is then λ 1 λ 2 λ 3 V 0 {\displaystyle \lambda _{1}\lambda _{2}\lambda _{3}V_{0}} and the total volume of the system is V 0 + V s 0 {\displaystyle V_{0}+V_{s0}} , that is assumed constant during the swelling process for simplicity of treatment. The swollen state of

3471-557: Is used almost exclusively in treating the hulls of wooden boats. Vegetable oils are increasingly being used in the electrical industry as insulators as vegetable oils are not toxic to the environment, biodegradable if spilled and have high flash and fire points. However, vegetable oils are less stable chemically, so they are generally used in systems where they are not exposed to oxygen , and they are more expensive than crude oil distillate. Synthetic tetraesters, which are similar to vegetable oils but with four fatty acid chains compared to

3560-501: Is used for the mass fraction of vapor in the steam. In alloys, especially those of noble metals, the term fineness is used for the mass fraction of the noble metal in the alloy. The mass fraction is independent of temperature until phase change occurs. The mixing of two pure components can be expressed introducing the (mass) mixing ratio of them r m = m 2 m 1 {\displaystyle r_{m}={\frac {m_{2}}{m_{1}}}} . Then

3649-413: Is used to fill the plastic tubes containing the fibers. The main purpose of the gel is to prevent water intrusion if the buffer tube is breached, but the gel also buffers the fibers against mechanical damage when the tube is bent around corners during installation, or flexed. Additionally, the gel acts as a processing aid when the cable is being constructed, keeping the fibers central whilst the tube material

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3738-544: Is used to produce biodiesel, or used directly as fuel in diesel cars which may require modification to heat the oil to reduce its higher viscosity . Other significant oils include: Seed oils are vegetable oils obtained from the seed ( endosperm ) rather than other parts of plants. Most vegetable oils are seed oils. Examples are sunflower, corn, and sesame oils. Claims that seed oils are unhealthy are not supported by scientific evidence. Oils are extracted first by expeller or cold pressing methods, then solvent expelling

3827-441: The elastic properties and firmness of the organogel. Often, these systems are based on self-assembly of the structurant molecules. (An example of formation of an undesired thermoreversible network is the occurrence of wax crystallization in petroleum .) Organogels have potential for use in a number of applications, such as in pharmaceuticals , cosmetics, art conservation, and food. A xerogel / ˈ z ɪər oʊ ˌ dʒ ɛ l /

3916-434: The 1930s and 1940s, and again in the 1970s and early 1980s when straight vegetable oil enjoyed its highest level of scientific interest. The 1970s also saw the formation of the first commercial enterprise to allow consumers to run straight vegetable oil in their vehicles. However, biodiesel , produced from oils or fats using transesterification is more widely used. Led by Brazil, many countries built biodiesel plants during

4005-490: The 1990s, and it is now widely available for use in motor vehicles, and is the most common biofuel in Europe today. In France, biodiesel is incorporated at a rate of 8% in the fuel used by all French diesel vehicles. In the mid-1970s, Canadian researchers developed a low-erucic-acid rapeseed cultivar. Because the word "rape" was not considered optimal for marketing, they coined the name "canola" (from "Canada Oil low acid"). The U.S. Food and Drug Administration approved use of

4094-482: The canola name in January 1985, and U.S. farmers started planting large areas that spring. Canola oil is lower in saturated fats, and higher in monounsaturates. Canola is very thin (unlike corn oil) and flavorless (unlike olive oil), so it largely succeeds by displacing soy oil, just as soy oil largely succeeded by displacing cottonseed oil. The production of vegetable oils went up 125% between 2000 and 2020, driven by

4183-443: The carbon atoms of the oil to break double-bonds with other carbons. Each carbon atom becomes single-bonded to an individual hydrogen atom, and the double bond between carbons can no longer exist. A fully hydrogenated oil, also called a saturated fat , has had all of its double bonds converted into single bonds. If a polyunsaturated oil is left incompletely hydrogenated (not all of the double bonds are reduced to single bonds), then it

4272-454: The charged nature of H + {\displaystyle {\text{H}}^{+}} and A − {\displaystyle {\text{A}}^{-}} , electrostatic interactions with other ions in the systems. This is effectively a reacting system governed by acid-base equilibrium modulated by electrostatic effects, and is relevant in drug delivery , sea water desalination and dialysis technologies. Due to

4361-419: The cotton seeds. The extracted oil was refined and partially hydrogenated to give a solid at room temperature and thus mimic natural lard, and canned under nitrogen gas. Compared to the rendered lard Procter & Gamble was already selling to consumers, Crisco was cheaper, easier to stir into a recipe, and could be stored at room temperature for two years without turning rancid. Soybeans are protein-rich, and

4450-403: The coupled acid-base equilibrium, electrostatics and network elasticity, only recently has such system been correctly recreated in computer simulations . Some species secrete gels that are effective in parasite control. For example, the long-finned pilot whale secretes an enzymatic gel that rests on the outer surface of this animal and helps prevent other organisms from establishing colonies on

4539-514: The elastic energy of one stand can be written as where R ref {\displaystyle R_{\text{ref}}} is the mean-square fluctuation in end-to-end distance of one strand. The modulus of the gel is then this single-strand elastic energy multiplied by strand number density ν = ϕ / N b 3 {\displaystyle \nu =\phi /Nb^{3}} to give This modulus can then be equated to osmotic pressure (through differentiation of

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4628-439: The elastic nature of the gel, the dispersion of A − {\displaystyle {\text{A}}^{-}} in the system is constrained and hence, there will be a partitioning of salts ions and H + {\displaystyle {\text{H}}^{+}} inside and outside the gel, which is intimately coupled to the polyelectrolyte degree of ionization. This ion partitioning inside and outside

4717-561: The exposure to oxygen, heat and light, resulting in the formation of oxidation products, such as peroxides and hydroperoxides , plant oils rich in polyunsaturated fatty acids have a limited shelf-life. In Canada, palm oil is one of five vegetable oils, along with palm kernel oil, coconut oil, peanut oil, and cocoa butter, which must be specifically named in the list of ingredients for a food product. Also, oils in Canadian food products which have been modified or hydrogenated must contain

4806-445: The extending fluid. Virtually any fluid can be used as an extender including water ( hydrogels ), oil, and air ( aerogel ). Both by weight and volume, gels are mostly fluid in composition and thus exhibit densities similar to those of their constituent liquids. Edible jelly is a common example of a hydrogel and has approximately the density of water. Polyionic polymers are polymers with an ionic functional group. The ionic charges prevent

4895-416: The final swollen gel, the second is associated with the initial gel and the third is of the pure solvent prior to mixing. Substitution of ϕ = ϕ 0 / λ 1 λ 2 λ 3 {\displaystyle \phi =\phi _{0}/\lambda _{1}\lambda _{2}\lambda _{3}} leads to Note that the second term is independent of

4984-627: The formation of tightly coiled polymer chains. This allows them to contribute more to viscosity in their stretched state, because the stretched-out polymer takes up more space. This is also the reason gel hardens. See polyelectrolyte for more information. A colloidal gel consists of a percolated network of particles in a fluid medium, providing mechanical properties , in particular the emergence of elastic behaviour. The particles can show attractive interactions through osmotic depletion or through polymeric links. Colloidal gels have three phases in their lifespan: gelation, aging and collapse. The gel

5073-430: The formula where M i {\displaystyle M_{i}} is the molar mass of the component i {\displaystyle i} , and M ¯ {\displaystyle {\bar {M}}} is the average molar mass of the mixture. Replacing the expression of the molar-mass products, In a spatially non-uniform mixture, the mass fraction gradient gives rise to

5162-404: The free energy) to give the same equation as we found above. Consider a hydrogel made of polyelectrolytes decorated with weak acid groups that can ionize according to the reaction is immersed in a salt solution of physiological concentration. The degree of ionization of the polyelectrolytes is then controlled by the pH {\displaystyle {\text{pH}}} and due to

5251-414: The gel is analogous to the partitioning of ions across a semipemerable membrane in classical Donnan theory, but a membrane is not needed here because the gel volume constraint imposed by network elasticity effectively acts its role, in preventing the macroions to pass through the fictitious membrane while allowing ions to pass. The coupling between the ion partitioning and polyelectrolyte ionization degree

5340-627: The gel is now completely characterized by stretch factors λ 1 {\displaystyle \lambda _{1}} , λ 2 {\displaystyle \lambda _{2}} and λ 3 {\displaystyle \lambda _{3}} and hence it is of interest to derive the deformation free energy as a function of them, denoted as f gel ( λ 1 , λ 2 , λ 3 ) {\displaystyle f_{\text{gel}}(\lambda _{1},\lambda _{2},\lambda _{3})} . For analogy to

5429-478: The gel would shrink to roughly its original size. This gel volume change can alternatively be introduced by applying external forces. If a uniaxial compressive stress is applied to a gel, some solvent contained in the gel would be squeezed out and the gel shrinks in the applied-stress direction. To study the gel mechanical state in equilibrium, a good starting point is to consider a cubic gel of volume V 0 {\displaystyle V_{0}} that

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5518-475: The historical treatment of rubber elasticity and mixing free energy, f gel ( λ 1 , λ 2 , λ 3 ) {\displaystyle f_{\text{gel}}(\lambda _{1},\lambda _{2},\lambda _{3})} is most often defined as the free energy difference after and before the swelling normalized by the initial gel volume V 0 {\displaystyle V_{0}} , that is,

5607-416: The hydrogel structure to obtain nanocomposites with tailored functionality. Nanocomposite hydrogels can be engineered to possess superior physical, chemical, electrical, thermal, and biological properties. Many gels display thixotropy – they become fluid when agitated, but resolidify when resting. In general, gels are apparently solid, jelly-like materials. It is a type of non-Newtonian fluid . By replacing

5696-488: The initial state. On the other hand, the mixing term f mix ( λ 1 , λ 2 , λ 3 ) {\displaystyle f_{\text{mix}}(\lambda _{1},\lambda _{2},\lambda _{3})} is usually treated by the Flory-Huggins free energy of concentrated polymer solutions f ( ϕ ) {\displaystyle f(\phi )} , where ϕ {\displaystyle \phi }

5785-485: The liquid with gas it is possible to prepare aerogels , materials with exceptional properties including very low density, high specific surface areas , and excellent thermal insulation properties. A gel is in essence the mixture of a polymer network and a solvent phase. Upon stretching, the network crosslinks are moved further apart from each other. Due to the polymer strands between crosslinks acting as entropic springs , gels demonstrate elasticity like rubber (which

5874-485: The mass fractions of the components will be The mass ratio equals the ratio of mass fractions of components: due to division of both numerator and denominator by the sum of masses of components. The mass fraction of a component in a solution is the ratio of the mass concentration of that component ρ i (density of that component in the mixture) to the density of solution ρ {\displaystyle \rho } . The relation to molar concentration

5963-424: The medium viscosity oil rendered from them was high in polyunsaturates. Henry Ford established a soybean research laboratory, developed soybean plastics and a soy-based synthetic wool, and built a car "almost entirely" out of soybeans. Roger Drackett had a successful new product with Windex , but he invested heavily in soybean research, seeing it as a smart investment. By the 1950s and 1960s, soybean oil had become

6052-454: The mixture. Expressed as a formula, the mass fraction is: Because the individual masses of the ingredients of a mixture sum to m tot {\displaystyle m_{\text{tot}}} , their mass fractions sum to unity: Mass fraction can also be expressed, with a denominator of 100, as percentage by mass (in commercial contexts often called percentage by weight , abbreviated wt.% or % w/w ; see mass versus weight ). It

6141-578: The most popular vegetable oil in the US; today it is second only to palm oil . In 2018–2019, world production was at 57.4 MT with the leading producers including China (16.6 MT), US (10.9 MT), Argentina (8.4 MT), Brazil (8.2 MT), and EU (3.2 MT). The early 20th century also saw the start of the use of vegetable oil as a fuel in diesel engines and in heating oil burners. Rudolf Diesel designed his engine to run on vegetable oil. The idea, he hoped, would make his engines more attractive to farmers who had

6230-429: The network contribution leads to This provides the starting point to examining the swelling equilibrium of a gel network immersed in solvent. It can be shown that gel swelling is the competition between two forces, one is the osmotic pressure of the polymer solution that favors the take in of solvent and expansion, the other is the restoring force of the polymer network elasticity that favors shrinkage. At equilibrium,

6319-548: The normal three found in a natural ester, are manufactured by Fischer esterification . Tetraesters generally have high stability to oxidation and have found use as engine lubricants. Vegetable oil is being used to produce biodegradable hydraulic fluid and lubricant . One limiting factor in industrial uses of vegetable oils is that all such oils are susceptible to becoming rancid . Oils that are more stable, such as ben oil or mineral oil , are thus preferred for industrial uses. Castor oil has numerous industrial uses, owing to

6408-427: The number of monomers remains the same while the gel volume has increased by a factor of λ 1 λ 2 λ 3 {\displaystyle \lambda _{1}\lambda _{2}\lambda _{3}} . As the polymer volume fraction decreases from ϕ 0 {\displaystyle \phi _{0}} to ϕ {\displaystyle \phi } ,

6497-436: The oil from seeds or fruits which are processed for edible purposes. Vegetable oils are also used to make biodiesel , which can be used like conventional diesel. Some vegetable oil blends are used in unmodified vehicles but straight vegetable oil , also known as pure plant oil, needs specially prepared vehicles which have a method of heating the oil to reduce its viscosity . The use of vegetable oils as alternative energy

6586-401: The oil mixture due to the heat used in hydrogenation. Partially hydrogenated oils and their trans fats have been linked to an increased risk of mortality from coronary heart disease , among other increased health risks. These concerns have led to regulations mandating the removal of partially hydrogenated oils from food. In the processing of edible oils, the oil is heated under vacuum to near

6675-451: The other with the mixing of the network with the solvent. Hence, we write We now consider the two contributions separately. The polymer elastic deformation term is independent of the solvent phase and has the same expression as a rubber, as derived in the Kuhn's theory of rubber elasticity : where G 0 {\displaystyle G_{0}} denotes the shear modulus of

6764-601: The phenomenon of diffusion . Vegetable oil Vegetable oils , or vegetable fats , are oils extracted from seeds or from other parts of edible plants . Like animal fats , vegetable fats are mixtures of triglycerides . Soybean oil , grape seed oil , and cocoa butter are examples of seed oils , or fats from seeds. Olive oil , palm oil , and rice bran oil are examples of fats from other parts of plants. In common usage, vegetable oil may refer exclusively to vegetable fats which are liquid at room temperature. Vegetable oils are usually edible. Olive oil has been

6853-426: The picture. Consider the case of two adjacent, initially uncharged acid sites HA {\displaystyle {\text{HA}}} are both dissociated to form A − {\displaystyle {\text{A}}^{-}} . Since the two sites are both negatively charged, there will be a charge-charge repulsion along the backbone of the polymer than tends to stretch the chain. This energy cost

6942-404: The presence of a hydroxyl group on the fatty acid. Castor oil is a precursor to Nylon 11 . Castor oil may also be reacted with epichlorohydrin to make a glycidyl ether which is used as a diluent and flexibilizer with epoxy resins. Vegetable oil is used in the production of some pet foods. AAFCO defines vegetable oil in this context as the product of vegetable origin obtained by extracting

7031-513: The rest of the oils from the leftover matter. This is a method used by larger capacity oil mills. As the energy consumption of the mechanical press increases as more oil is released, it is more efficient to extract the rest of the oil (past around 60%) by solvent extraction. A large quantity of used vegetable oil is produced and recycled, mainly from industrial deep fryers in potato processing plants, snack food factories and fast food restaurants . Recycled oil has numerous uses, including use as

7120-471: The smoke point or to about 232 °C (450 °F), and water is introduced at the bottom of the oil. The water immediately is converted to steam, which bubbles through the oil, carrying with it any chemicals which are water-soluble. The steam sparging removes impurities that can impart unwanted flavors and odors to the oil. Deodorization is key to the manufacture of vegetable oils. Nearly all soybean, corn, and canola oils found on supermarket shelves go through

7209-466: The stretching factors λ 1 {\displaystyle \lambda _{1}} , λ 2 {\displaystyle \lambda _{2}} and λ 3 {\displaystyle \lambda _{3}} and hence can be dropped in subsequent analysis. Now we make use of the Flory-Huggins free energy for a polymer-solvent solution that reads where v c {\displaystyle v_{c}}

7298-423: The subject discusses the use of hydrogels for nucleus pulposus replacement, cartilage replacement, and synthetic tissue models. Many substances can form gels when a suitable thickener or gelling agent is added to their formula. This approach is common in the manufacture of a wide range of products, from foods to paints and adhesives. In fiber optic communications, a soft gel resembling hair gel in viscosity

7387-536: The surface of these whales' bodies. Hydrogels existing naturally in the body include mucus , the vitreous humor of the eye, cartilage , tendons and blood clots . Their viscoelastic nature results in the soft tissue component of the body, disparate from the mineral-based hard tissue of the skeletal system. Researchers are actively developing synthetically derived tissue replacement technologies derived from hydrogels, for both temporary implants (degradable) and permanent implants (non-degradable). A review article on

7476-435: The term 'hydrogel' in the literature was in 1894. An organogel is a non-crystalline , non-glassy thermoreversible ( thermoplastic ) solid material composed of a liquid organic phase entrapped in a three-dimensionally cross-linked network. The liquid can be, for example, an organic solvent , mineral oil , or vegetable oil . The solubility and particle dimensions of the structurant are important characteristics for

7565-528: The total mass of a sample. In these contexts an alternative term is mass percent composition . The mass fraction of an element in a compound can be calculated from the compound's empirical formula or its chemical formula . Percent concentration does not refer to this quantity. This improper name persists, especially in elementary textbooks. In biology, the unit "%" is sometimes (incorrectly) used to denote mass concentration, also called mass/volume percentage . A solution with 1   g of solute dissolved in

7654-493: The two effects exactly cancel each other in principle and the associated λ 1 {\displaystyle \lambda _{1}} , λ 2 {\displaystyle \lambda _{2}} and λ 3 {\displaystyle \lambda _{3}} define the equilibrium gel volume. In solving the force balance equation, graphical solutions are often preferred. In an alternative, scaling approach, suppose an isotropic gel

7743-567: The word "modified" or "hydrogenated" when listed as an ingredient. A mix of oils other than the aforementioned exceptions may simply be listed as "vegetable oil" in Canada; however, if the food product is a cooking oil, salad oil or table oil, the type of oil must be specified and listing "vegetable oil" as an ingredient is not acceptable. From December 2014, all food products produced in the European Union were legally required to indicate

7832-453: The workplace as 15 mg/m total exposure and 5 mg/m respiratory exposure over an 8-hour workday. The U.S. National Institute for Occupational Safety and Health (NIOSH) has set a recommended exposure limit (REL) of 10 mg/m total exposure and 5 mg/m respiratory exposure over an 8-hour workday. Typical productivity of some oil crops, measured in tons (t) of oil produced per hectare (ha) of land per year (yr). Oil palm

7921-642: The xerogel due to a small amount of viscous flow) which results in a denser and more robust solid, the density and porosity achieved depend on the sintering conditions. Nanocomposite hydrogels or hybrid hydrogels, are highly hydrated polymeric networks, either physically or covalently crosslinked with each other and/or with nanoparticles or nanostructures. Nanocomposite hydrogels can mimic native tissue properties, structure and microenvironment due to their hydrated and interconnected porous structure. A wide range of nanoparticles, such as carbon-based, polymeric, ceramic, and metallic nanomaterials can be incorporated within

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