Aplicações

Propylene oxide (PO) is a major industrial product used in assorted industrial applications, mainly for the production of polyols (the building blocks for polyurethane plastics). Several production methods exist, with and without co-products. This white paper lays out opportunities to optimize PO production for safer and more efficient processes, higher quality products, and substantial time savings by using online process analysis instead of laboratory measurements.

Os poliuretanos são um dos tipos de plástico mais comumente usados. Eles são produzidos pela reação de polióis brutos com isocianatos. Dependendo do material de partida pode ser obtida uma grande variedade de plásticos. A determinação do índice de acidez, do índice de hidroxila e do teor de isocianato desempenha um papel importante na análise de matérias-primas para plásticos. O índice ácido da matéria-prima poliol é geralmente usado no controle de qualidade para garantir a uniformidade entre lotes. Além disso, é usado como fator de correção para calcular o verdadeiro número de hidroxila. Neste Boletim de Aplicação é descrita a determinação do índice de acidez de acordo com ASTM D4662 e ASTM D7253. Uma matéria-prima para poliuretanos são os polióis. Os polióis contêm vários grupos hidroxila. Portanto, o número de hidroxila de uma matéria-prima se correlaciona diretamente com a quantidade de polióis presentes e é, portanto, um importante parâmetro de controle de qualidade. Neste Boletim de Aplicação é descrita a determinação do índice de hidroxila de acordo com ASTM E1899 e DIN 53240-3. Como os polióis reagem estequiometricamente com os isocianatos, o conhecimento do teor de isocianato é um importante parâmetro de qualidade para a produção de poliuretanos. Neste documento é descrita a determinação de acordo com EN ISO 14896 método A, ASTM D5155 método A e ASTM D2572.

Caprolactam is an important polymer used for the production of Nylon 6, which is the base material for industrial fibers. Due to its commercial significance, many different synthesis methods have been developed over the years. Caprolactam is hygroscopic and water soluble, therefore it is important to have a reliable analysis technique for water determination. Analyzing the water content by conventional methods requires each sample to be weighed, dissolved, heated, and titrated. Compared to the primary method, near-infrared spectroscopy (NIRS) offers unique advantages: it generates reliable results within seconds, but it does not need any sample preparation nor does it create chemical waste.

Acrylic acid dimerizes spontaneously. Determining the dimer content is, therefore, a key part of the quality control for acrylic acid. One quality control parameter for the dimerization is the acid number. This Application Note describes its determination by automated, potentiometric titration.

The hydroxyl number is an important sum parameter for quantifying the presence of hydroxyl groups in a chemical substance. As a key quality parameter, it is regularly determined in various polymers like resins, paints, polyesterols, fats and solvents. Unlinke other standards, ASTM E1899 works pyridine-free and without refluxing at elevated temperatures for a longer time. It is performed at room temperature, requires only a small sample size, is applicable to extremely low hydroxyl numbers (<1 mg KOH/g sample) and can be performed fully automatically. This Application Note describes the potentiometric determination of the hydroxyl number in 1-octanol and polyethylene glycol according to ASTM E1899, EN 15168 and DIN 53240-3. Using the OMNIS DIS-Cover technique all sample preparation steps can be fully automated. Moreover, the use of an OMNIS Sample Robot allows parallel analysis of multiple samples. The average time per analysis for one sample is thus reduced from approximately 24 min to 12 min., increasing productivity in the laboratory considerably.

This e-book explains how Raman and near-infrared (NIR) spectroscopy enable rapid, nondestructive polymer analysis, ensuring high quality while reducing costs and waste.

Raman spectroscopy can easily monitor polymerization by tracking monomer consumption and polymer formation, providing a valuable tool for polymer manufacturers.

The water content of beta-caprolactam is determined according to Karl Fischer.

This Application Note describes the determination of multiple quality parameters (hydroxyl number, acid number, and moisture content) of polyols using Vis-NIRS. Without any sample preparation, this unique analytical technique enables straightforward quantitative analysis.

Toxic and corrosive chemicals such as p-toluenesulfonyl isocyanate (TSI) and tetrabutylammonium hydroxide are used for the Hydroxyl Number analysis of polyols by titration according to ASTM D4274-16. This application note demonstrates how the XDS RapidLiquid Analyzer operating in the visible and near-infrared spectral region (Vis-NIR) provides a cost-efficient and fast solution for the determination of the hydroxyl (OH) number of polyols. With no sample preparation or chemicals needed, Vis-NIR spectroscopy allows for the analysis of polyols in less than a minute.