In-depth Analysis of a High Score** Sexual Identity

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Analysis of a High-Performance Polymer: Abstract: An infrared spectroscopy method was used to analyze a high-performance polymer; by interpreting the spectral data in conjunction with chemical analysis, the composition of the sample was determined, laying the foundation for the development of new high-performance polymers. Keywords: infrared spectroscopy, high-performance polymers, sample analysis. High-performance polymers are polymer materials that have seen rapid development in recent years; they are widely used in industries such as the automotive industry, aviation industry, construction, and textiles, playing a significant role in the development of the national economy. To meet the needs of national economic development, it is essential to research and develop new high-performance materials. The author used infrared spectroscopy in combination with chemical analysis to study a widely applicable high-performance material, analyzed its composition, and determined the makeup of the sample, thereby providing a solid basis for the development of new high-performance materials. 1 Experimental Section l, l Instruments and Reagents Instruments: Hitachi 260-50 infrared spectrophotometer Reagents ； Chloroform, anhydrous ethanol, petroleum ether, rosin acid, **furan, propylene, styrene-butadiene copolymer, liquid paraffin ； Sample: Unknown high-molecular-weight substance. 1.2 Preliminary experiments: The sample is highly elastic, has a sticky surface with an oily appearance, and exhibits strong adsorption properties. 1.3 Solubility test: A small amount of the sample was added to petroleum ether, chloroform, anhydrous ethanol containing furan, and it was found that the sample was soluble in chloroform but insoluble in petroleum ether, furan, propane, and ethanol. 1.4 Combustion Test: Take a small amount of the sample to be analyzed (approximately 0.1 g in mass), place it on a stainless steel spatula, heat it gradually until it catches fire. While the sample is burning, observe its combustion characteristics, as shown in the attached table. Through the flammability test, the sample softened and turned into droplets upon heating, indicating that it is a thermoplastic elastomer ； The large amount of black smoke produced during combustion indicates that this elastomer may contain benzene ring structures. 1.5 Sample preparation: Film sample preparation. Dissolve the sample, use a capillary to draw drops of the sample solution onto a clean KBr pellet, and allow the solvent to evaporate; then plot the graph, with the resulting spectrum shown in Figure 1. 1.6 Separation and purification of 6 components: The dissolution-precipitation method is used to separate polymer materials. The high-molecular-weight substance is dissolved in chloroform to form a concentrated solution; while stirring continuously, the precipitant (ethanol) is added drop by drop to the solution until it becomes turbid. Afterwards, the addition rate of the precipitant is increased, with the amount added being 10 times that of the high-molecular-weight solution. Let it stand, filter out the precipitate, dissolve the precipitate in chloroform for plotting, as shown in Figure 2. The solvent in the filtrate was evaporated to dryness, yielding an oil mixture; a plot is shown in Figure 4. The oil mixture was extracted repeatedly with ethanol, yielding two substances: an oil layer and an ethanol layer. The oil layer smear was fed into the imaging system to generate a plot, as shown in Figure 5. The ethanol layer was heated in a water bath to evaporate the ethanol, and the residue was plotted, as shown in Figure 6. 2 Spectrum analysis: As can be seen from Figure 1, there is a relatively wide absorption peak around 2,900 cm-1, and another absorption peak exists above 3,000 cm-1. In addition, absorption peaks corresponding to the skeletal vibrations of the benzene ring are present at 1,600 and 1,500 cm-1, further confirming that the unknown substance contains a benzene ring structure. As can be seen from Figure 2, absorption is present above 3,000 cm-1, and there are absorption bands due to the vibration of the benzene ring framework at 1,600 and 1,500 cm-1. This indicates that the precipitate is an aromatic polymer. According to literature, the high-performance polymer containing a benzene ring is styrene-butadiene rubber; a plot using standard styrene-butadiene rubber is shown in Figure 3. By comparing Figure 3 with Figure 2, as in the case of the two figures, it can be determined that the precipitate obtained through extraction is styrene-butadiene rubber. As can be seen from Figure 4, there is an absorption peak at 1700 cm-1, indicating that the additive contains acids. There are strong absorption peaks at 2,900, 1,460, and 1,380 cm-1; it is preliminarily determined that the hydrocarbons are straight-chain alkanes. As can be clearly seen from Figure 5, the oil layer consists of straight-chain alkanes. According to literature, paraffin oil is commonly used as an additive to improve compressive resilience and compressive set. Therefore, it is reasonable to assume that the oil layer consists of liquid paraffin; this was confirmed by comparing with standard liquid paraffin using a calibration curve. 2.5 The Cr(II) standard solutions were prepared by stepwise dilution, with concentrations of 0.00, 1.00, 2.00, 3.00, 4.00, 5.00, 6.00, 7.00, and 8.00 (×10^-8 g/mL). To each of these solutions, 10 mL of 2.5 mol/L KBr solution and 25 mL of 0.1 mol/L EDTA solution were added. The pH was adjusted to 3.50, and the mixture was diluted to 50 mL with NaCl-HCl aqueous solution at pH 3.50 to achieve the final volume. After adding the EDTA solution, measurements began after 5 minutes. A regression analysis was performed using the peak height and concentration; the equation of the working curve obtained was y=0.18+2.02x, with a correlation coefficient of r=0.998. 2.6 Results of sample analysis: 2.5 g of grape sample was weighed and placed in a 150 mL conical flask, to which V(HClO4) was added ； 5 mL of a concentrated acid solution of V(HNO3) at a ratio of 1:4. Heat to carry out the digestion reaction; once all brown gas has dissipated, the sample becomes clear and white smoke appears, remove it from heat and cool it. Add a small amount of water along the wall of the bottle, then heat again until white smoke appears. Remove it from heat again, add 30 mL of water, 3 mL of 6% NaHSO3, and 1 mL of HNO3, mix well, and heat to a boil for 10 minutes before cooling. Transfer the solution to a small beaker, add 2.5 mL of 0.1 mol/L EDTA solution and 10 mL of 2.5 mol/L KBr solution, adjust the pH to 3.5, then transfer the solution to a 50 mL volumetric flask and bring the volume to the mark with NaCl-HCl solution at pH 3.50. The measurement began 5 minutes after adding the EDTA solution, with a blank experiment conducted simultaneously. The sample analysis results are shown in Table 3.