• Stearic Acid is a saturated fatty acid with 18 carbon chain and has the IUPAC name octadecanoic acid. It is a waxy solid and its salts and esters are called Stearates.
• Stearic acid is obtained from fats and oils by saponification of triglycerides using hot water.
Bifunctional Characteristics of Stearic Acid:
• Stearic acid exploit its bifunctional character, with a polar head group that can be attached to metal cation and a non polar chain that confers solubility in organic solvents.
• This combination leads to uses as a surfactant and softening agent.
• Stearic acid is an organic compound that are amphiphilic in nature, i.e., they contain both hydrophobic (water insoluble) and hydrophilic (water soluble) group.
Vulcanization:
• Vulcanization
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It reacts with most accelerators to form the highly active zinc salt.
• Complex formation of the zinc ion with different accelerators is critical to get efficient curing. A preceding reaction with stearic acid forms the hydrocarbon-soluble zinc stearate and liberates water before the onset of crosslinking
• It has been suggested in many different studies that these active complexes of Zn²⁺ ions with accelerators are more reactive than the free accelerator.
• This active sulphurating agent reacts at the allylic sites of the rubber polymer unsaturations to form a rubber bound intermediate, which reacts with another rubber bound intermediate or with another polymer chain to generate a crosslink. The exact activator role of ZnO is highly dependent on the type of accelerator present in the initial vulcanisation system.
Role of Stearic Acid in Sulfur Vulcanization:
• The acceleration system often needs some proportion of fatty acid (like Stearic acid) for cure activation.
• In general, fatty acids as co-activators in rubber vulcanisation increase the crosslink
In a small reaction tube, the tetraphenylcyclopentadienone (0.110 g, 0.28 mmol) was added into the dimethyl acetylene dicarboxylate (0.1 mL) and nitrobenzene (1 mL) along with a boiling stick. The color of the mixed solution was purple. The solution was then heated to reflux until it turned into a tan color. After the color change has occurred, ethanol (3 mL) was stirred into the small reaction tube. After that, the small reaction tube was placed in an ice bath until the solid was formed at the bottom of the tube. Then, the solution with the precipitate was filtered through vacuum filtration and washed with ethanol. The precipitate then was dried and weighed. The final product was dimethyl tertraphenylpthalate (0.086 g, 0.172mmol, 61.42%).
The compound that is formed is 17alpha-propiolic acid which is reduced to the lactone. Then the solution is oxidized and treated with thioacetic acid and chloranil that finally create spironolactone, also known as 17-hydroxy-7α-mercapto-3-oxo-17α-pregn-4-ene-21-carboxylic acid γ-lactone acetate (6). Spironolactone has a melting point of 198 degrees Celsius to 207 degrees Celsius. It is insoluble in water, but soluble in benzene, ethyl acetate, and alcohol. The solubility of Spironolactone increases with increasing polarity of the solvent. The IR spectrum of spironolactone shows a conjugate carbonyl group and a lactone carbonyl present in the structure
head group is attached to one of the glycerol hydroxyls with addition to the two hydrocarbon fatty
14. Erucic acid is a long-chain unsaturated fatty acid. Like oleic acid, it suppresses the creation of VLCFSAs, but is much more
Omega-3 fatty acids are essential fatty acids that one needs to obtain from the diet to maintain health. There are three types of omega-3 fatty acids involved in human function, which are also known as polyunsaturated fatty acids. These are ALA (α-linolenic acid), EPA (eicosapentaenoic acid), and DHA (docosahexaenoic acid). ALA is a short chain fatty acid that is derived from plant sources such as flaxseed oil and hemp oil. EPA and DHA are long-chain fatty acids that are found mostly from animal sources such as fatty fish.
of a zwitterion is made possible due to the basic properties of the NH2 group
Ensure gloves are worn at all times when handling strong acids and bases within the experiment of the preparation of benzocaine. 4-aminobenzoic acid (3.0g, 0.022 moles) was suspended into a dry round-bottomed flask (100cm3) followed by methylated sprits (20 cm3). Taking extra care the concentrated sulphuric acid of (3.0 cm3, 0.031 moles) was added. Immediately after the condenser was fitted on, and the components in the flask were swirled gently to mix components. It should be ensured that the reactants of the concentrated sulphuric acid and the 4-aminobenzoic acid were not clustered in the ground glass joint between the condenser itself and the flask. In order to heat the mixture to a boiling point, a heating mantle was used and then further left for gently refluxing for a constituent time of forty minutes. After the duration of the consistent forty minutes the rou...
Prepare .05 to .075 g of crude lipid by dissolving it in hexane. Add to the silica gel slurry in the column.
Chemical: Acids in foods and beverages such as citrus fruits, spices, wines and carbonated beverages; acids produced by acidogenic bacteria following carbohydrate exposure; acids from gastric regulation. (Wilkins, BS, RDH, DMD, 2013)
Varying the n value carries out the experiment. Absorbencies of each of the ZLn complexes are obtained. The sum of the concentrations of the metal, Z, and the ligand, L, are kept equal. With the ratio of the ligand to the metal in the solution with the maximum absorbance for the ZLn complex, the value of n can be determined as well as the composition of ZLn.
...eicosapentaenoic acid), and ALA (alpha-linolenic acid) are considered to be the three main fatty acids.
This is an example of a soap molecule. The hydrocarbon end is non polar and hydrophilic (water hating) and the carboxylate end is polar and hydrophilic (water loving). This the property which allows it to clean, it acts as an emulsifying agent. The soap disperses in water to form miscelles where a negatively charged surface is formed and hydrocarbon chains are in the centre. These miscelles surround droplets of dirt or grease suspending them in the water so they can be washed away.
The acid contained such as malic and tartaric acid actually work to dissolve the
Now a days the skim milk is used in the making of other products. There is also a type of butter which contain approximately 80-82% milk fat, 16-17% water and 1-2% milk solids called viable butter and may also contain salt or may not contain salt and is in the form of sweet butter. Calcium, phosphorus, protein and vitamin soluble in fats such as vitamin A, D and E may also be present in butter. Methyl ketone, fatty acids, lactones, diacetyl and dimethyl are five major compounds that contribute to the flavor of butter. Butter is chemically a mixture of triglycerides especially those that are derived from fatty acids palmitic, oleic, myrisyic and stearic acid
Fatty acids are another type of lipid. The common feature of fatty acids is that they are all esters of moderate to long chain fatty acids. Two polyunsaturated fatty acids, linoleic and linoleic, are designated "essential" because their absence in the human diet has been associated with health problems, such as scaly skin, stunted growth and increased dehydration. These acids are also precursors to the prostaglandins, a family of physiologically potent lipids present in minute amounts in most body tissues.