N- hydroxymethyl acrylamide

This product is white crystalline powder, which is easily soluble in water, alcohol and acetone. Slightly soluble in benzene and toluene.

The molecular formula is CH2＝CHCONHCH2OH

Molecular weight: 101.10 (according to 1979 international atomic weight)

I. Technical requirements

N- hydroxymethyl acrylamide shall meet the following requirements

Second, below, Jiangsu Chemical Plant teaches you several inspection methods

1. measurement of appearance

Visual inspection.

2. Determination of melting point range (according to GB617 Melting Point Determination Method)

3. Determination of total aldehyde content

Accurately weigh 0.45g sample (weighed to 0.0002g) and put it in a 100ml volumetric flask. Dilute to scale (solution I). Accurately weigh 5.0ml of solution I, put it in a 250ml iodine volumetric flask, and add 25.0ml of iodine standard solution [c (1/2i2) = 0.1mol/l] and 30ml of 1mol/l sodium hydroxide solution. Close the bottle stopper, keep the temperature in water bath at 55 2℃ for 15min, and add 12.5ml of 6mol/L hydrochloric acid after cooling. Iodine precipitated is titrated with 0.1mol/L sodium thiosulfate standard solution, and 1ml0.5% starch solution is used as indicator near the end point, and drops to blue and disappears, and a blank test is made at the same time.

Total aldehyde quantity X1(%) is calculated according to formula (1):

X1＝[(V0－V)c*0.015]/m*100（1）

In which:

V0—— the volume of sodium thiosulfate standard solution used in titration blank test, ml;

V—— the volume of hydrochloric acid standard solution required for sample titration, ml;

M—— mass of sample, g;

0.015—— mass of formaldehyde equivalent to each millimolar titration solution, g;

C—— molar concentration of sodium thiosulfate standard solution used in titration.

4. Determination of free aldehyde

Weigh 2g sample (weighed to 0.0002g) and put it in a 250ml iodine volumetric flask. Use 15ml of water to dissolve, then add 5ml of 10% ammonium chloride and 10ml of 0.5mol/L sodium hydroxide, immediately close the bottle stopper and leave for 30min. 3 drops of bromothymol blue were used as indicator. With 0.5mol/L hydrochloric acid standard solution titration. When the solution changes from blue to green, it will be finally narrowed, and a blank test will be done at the same time.

The free aldehyde X2(%) is calculated according to formula (2):

X2＝[(V0－V)c*0.004503]/m*100（2）

In which:

V0—— the volume of hydrochloric acid standard solution required for blank test, ml;

V—— standard volume of hydrochloric acid required for sample titration, ml;

M—— mass of sample, g;

0.004503(6/4*0.03002)—— millimolar grams when formaldehyde reacts with ammonium hydroxide;

C—— concentration of hydrochloric acid standard solution required for titration.

5. Determination of content

Accurately take 3.0ml solution I and put it in a 250ml iodine volumetric flask. Add 20.0ml of 0.1mol/l bromine solution and 25ml of [c (1/2h2so4) = 1mol/l] sulfuric acid, immediately close the bottle stopper, and place it in the dark for 40min. Add 5%KI25ml (added around the bottle stopper to avoid bromine escaping), titrate with 0.1mol/L sodium thiosulfate standard solution after 5min, add 1ml of 0.5% starch solution as indicator near the end point, and then titrate to colorless (meanwhile, do blank test).

The content X3(%) is calculated according to formula (3):

X3＝[(V0－V)c*0.05055*20]/m*100（3）

In which:

V0—— the volume of sodium thiosulfate standard solution used in blank test, ml;

V—— the volume of sodium thiosulfate standard solution required by the sample, ml;

M—— sample mass, g;

0.05055—— The standard solution of sodium thiosulfate used is converted into grams of millimoles of sample.

C—— the molar concentration of sodium thiosulfate standard solution used.