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Do you know about the "Introduction of Triethylene Diamine Detection Method Triethylene Diamine Application Introduction"? Today Changzhou Mingshun Chemical Co., Ltd. will introduce you to this aspect. I hope that through the introduction of this article, you will be able to I have a certain knowledge and understanding of the application introduction of triethylenediamine and other aspects. Let’s take a look at the related introductions:

Introduction to the hazard category of piperazine hexahydrate. The detection method of triethylenediamine. Introduction to the application of triethylenediamine

Analysis method: chromatographic analysis

Analytical instrument: GC7890 gas chromatograph, column type: SE-54, 30 meters.

Moisture Analyzer: KF---1 type

The main content analysis process: 1. Gas column temperature: 200 degrees; sampling temperature: 240 degrees; vaporization chamber temperature: 240 degrees; dissolve the anhydrous piperazine sample in appropriate methanol, and the injection volume is 0.2 microliters. After the sample is injected, press the "Fl key" to obtain the content of methanol and piperazine by the area normalization method. Remove the content of methanol to obtain the content of piperazine.

Moisture measurement process: After the moisture analyzer is calibrated, pour in the proper anhydrous methanol. It is advisable to swallow the exposed electrode, start stirring, and titrate the moisture in the methanol with Karl Fischer reagent to make the pointer deflect a lot and hold for one minute. The change is over, there is no water at the moment, and then press the method

Participate in distilled water: Use a micro syringe to write 0.01---0.04 grams of water into the reaction flask from the feeding port, or weigh distilled water to participate in the reaction flask, and then calibrate according to the above operation.

T = m ×lOOO/ v

T: Water equivalent of Karl Fischer reagent (mg water/ml):

M: weight of water (g)

V: the volume of Karl Fischer reagent consumed in titration (ml)

Weigh the sample with a weighing tube, add anhydrous methanol to the reaction flask, swallow the exposed electrode, titrate with Karl Fischer reagent until the galvanometer has the same deflection during calibration, and hold it unchanged for one minute, turn on the feed Close the rubber stopper, quickly pour the weighing tube sample into the reaction flask, immediately close the rubber stopper, stir the solution until the sample is dissolved, and introduce it. The detection method of triethylenediamine is introduced and the Karl Fischer reagent is titrated as above.

The percentage of moisture content is calculated as follows:

Δ% = T × V/10×m

T: Water equivalent of Karl Fischer reagent (mg water/ml):

V: the volume of Karl Fischer reagent consumed in titration (ml)

M: the weight of the sample (g)

More concerned: [Picture] What are the dangers of piperazine What are the measures to protect anhydrous piperazine

Triethylenediamine is a tertiary amine compound with a double heterocyclic structure. It is mainly used as a gel catalyst for polyurethane foam. It is widely used in soft, semi-rigid and rigid polyurethane foam and elastomers. In addition, it can also Used as epoxy resin curing catalyst, ethylene polymerization catalyst, acrylonitrile polymerization catalyst-based ethylene oxide hydrocarbon polymerization catalyst, hexahydropyridine and other pesticide production initiators, and non-hydrogen electroplating additives. The chemical structure of triethylenediamine is very similar. It is a cage compound with three ethylene groups connected to two nitrogen atoms. The structure of this bicyclic molecule is very full and symmetrical. It can be seen from the structure that there is no substitution group with great steric hindrance on the N atom, and its pair of empty electrons are easy to approach. In the foaming system, the isocyanate first reacts with it to form an active complex. The nature of the complex is very unstable. Once the urethane bond is formed, it will be freed, which is conducive to further catalysis. Although triethylenediamine is not a strong base, it exhibits extremely high catalytic activity for the reaction of isocyanate groups and active hydrogen compounds. Among the tertiary amine catalysts, triethylenediamine is the most important species, which can be widely used in various polyurethane foams (including soft, semi-rigid, rigid polyurethane foams, microcellular elastomers), coatings , Elastomers, etc. In the one-step foaming technique, triethylenediamine is notable for its main character. On the one hand, due to its high activity, the dosage is small; the second is other

has a strong catalytic effect on the gel reaction and foaming reaction, and the catalysis on polyurethane and hydroxyl (urethane formation reaction, gel reaction) is more selective.

The points introduced above are about "Introduction to the application of triethylenediamine detection method". I believe that after reading the introduction of this article, I will have my own understanding of this aspect. Problems such as introduction to the application of ethylene diamine can also be solved well. Here, we, you know more about testing long-tail words, triethylenediamine manufacturers, etc., and hope to help you!

Keywords in this article: introduction ethylene reaction catalysis Karl reagent methanol