EPOXY REACTIONS Cross-linkage and Reaction of an Epoxy Resin ABSTRACT In this experiment the polymerization reactions with epoxy resins are studied. Cross-linked and chain polymers are synthesized with the reaction of reactive oxirane structure in Dow D.E.R. 331 epoxy resin respectively with MDAP and piperazine. The physical differences of two polymers are observed and IR spectrometry of the piperazine and epoxy resin reaction is taken, characteristic epoxy peak and O-H peak transmittance changes which show the reaction progress were determined. INTRODUCTION Epoxy resins are chemicals that are resistant corrosion, have good mechanical and thermal properties, good electric insulating properties and low shrinkage upon curing.
The general concept of distillation involves the boiling of a mixture, resulting in the lower boiling compounds boiling off first. This compound is then collected when the vapors are cooled on a condenser. Several different techniques exist for specific applications. The most commonly used method is the simple distillation apparatus (Figure 1). This results in the vapors being collected and affords one solution in moderate purity.
Experiment 2.13.: Micro-scale Synthesis of Triphenylmethanol Aim: This was a two part experiment in which the aim of the first part was to synthesise the Grignard reagent phenylmagnesiumbromide from reacting bromobenzene with magnesium and diethyl ether. The aim of the second part was to synthesise the alcohol triphenylmethanol using the previously produced phenylmagnesiumbromide by reacting it with benzophenone. Introduction: This experiment involved two reactions. First the Grignard reagent, phenylmagnesiumbromide, was synthesised from bromobenzene, magnesium and diethyl ether. Once produced, the Grignard reagent was then used to synthesise triphenylmethanol by reacting it with benzophenone.
Mixture is gently swirled and drained out into an Erlenmeyer flask. Anhydrous magnesium sulfate is added to dehydrate the washed mixture. The solution is then filter into a weighed, dry, 100mL Erlenmeyer flask. Dichloromethane in the mixture is vaporized with a rotary evaporator. The Caffeine, white powder residue, (0.0486g) should be obtained.
Analysis of two analytes using Thin-layer chromatography Thin layer chromatography (TLC) is a simple, suitable and not an expensive type of chromatography technique used to determine the number of components in a mixture, test the purity of compounds, separate the mixture from their compounds as compounds are absorbed in different degree levels and differ in terms of solubility. TLC consists of a stationary phase coated by silica gel and attached on a glass or a plastic plate and an organic solvent, the sample is then placed on the stationary phase as spots using capillary tube, the sample can either be liquid or liquefied in volatile solvent. Silica gel is a type of silica. The atoms of the silica are attached to oxygen atoms through covalent structure. The silicon atoms are connected to –OH groups on the outside of the silica gel.
LIQUID-LIQUID EXTRACTION OF BENZOIC ACID J Wright Organic Chem Lab 1 Tuesday 1:40-5 Ian Stubbs LIQUID-LIQUID EXTRACTION OF BENZOIC ACID PURPOSE: The purpose of this experiment was to extract benzoic acid from an aqueous of benzoic acid using methylene chloride, use liquid-liquid extraction to calculate the distribution coefficient of benzoic acid and to determine whether a single extraction or multiple extractions are more efficient. Add in the table of physical constants. See the attachment for the lab format. PROCEDURE: Gather a two stock solution that includes; 0.02M of sodium hydroxide (NaOH) aqueous solution and 0.02M of benzoic acid aqueous solution. For a single extraction, use a 50mL graduated cylinder and measure out 50mL of the benzoic acid solution into a 125mL separatory funnel.
If the solution of water and caffeine is mixed with the solvent dichloromethane, the caffeine is transferred to the dichloromethane. This results from the fact that caffeine is much more soluble in dichloromethane than water. Water and dichloromethane are not soluble in each other. The volatile dichloromethane can easily be vaporized off from the dichloromethane/caffeinesolution leaving fairly pure solid caffeine. In the process the solubilities of cellulose, tannins, and of chlorophyll will be considered.
Experiment 8 : Ramen Spectroscopy Objective: To utilize Raman Spectroscopy as an analytical chemistry tool to determine (i) the composition of an unknown chloroform/benzene mixture (ii) the amount of ethanol in vodka. Pre-lab questions: 1) What is a calibration curve and how would you go about constructing one? A calibration curve shows the response of an analytical method to known quantities of an analyte. To construct a calibration curve, we first prepare known samples of the analyte covering a range of concentrations expected for the unknowns and measure the response of the analytical procedures of these standards to generate signal data. After the measurement is done, a linear graph of the signal data against analyte concentration is plotted.
Reaction Scheme [pic] Although sulfanilic acid is insoluble in acid solutions, it is nevertheless necessary to carry out the diazotization reaction in an acid (HNO2) solution. This problem can be avoided by precipitating sulfanilic acid from a solution in which it is initially soluble. The precipitate is a fine suspension and reacts instantly with nitrous acid. The first step is to dissolve sulfanillic acid in basic solution. When the solution is acidified during diazotization to form nitrous acid, the sulfanilic acid is precipitated out of solution as a finely divided solid, which is immediately diazotized.