Esterification reagent and method for determining resin hydroxyl value
A resin and hydroxyl value technology, applied in the field of hydroxyl value detection of polymer materials, can solve the problems of long measurement process time, volatile acylation reagent, strong irritation, etc., to overcome the poor reproducibility of results, improve the working environment, The effect of reducing time
- Summary
- Abstract
- Description
- Claims
- Application Information
AI Technical Summary
Problems solved by technology
Method used
Image
Examples
Embodiment 1
[0056] The present embodiment provides a kind of method of measuring resin hydroxyl value, comprises the following steps:
[0057] (a) Prepare hydrochloric acid standard solution: Take 36 mL of concentrated hydrochloric acid and add it to a 2000 mL volumetric flask, then add ethanol to the volumetric line of the volumetric flask to make a constant volume;
[0058] (b), calibrate the concentration of hydrochloric acid standard solution: anhydrous Na 2 CO 3 Baked at 300°C for 0.5 h, accurately weighed 0.2525 g with an electronic balance and added to 50 mL of deionized water to form Na 2 CO 3 Solution, add 5 drops of bromothymol blue as an indicator, titrate with hydrochloric acid standard solution until the solution is light yellow, and this Na 2 CO 3 Boil the aqueous solution in water at 100°C until it turns blue, then add the standard hydrochloric acid solution dropwise until light yellow, cook again, repeat the operation until the color does not change after cooking, and ...
Embodiment 2
[0074] This embodiment also provides a method for measuring the hydroxyl value of the resin. The specific steps are the same as in Embodiment 1, except that the selected resin samples are different. In this example, a commercial unsaturated polyester is selected, its hydroxyl value ranges from 20 to 25, its acid value AN is 0.86 mgKOH / g, and its solid content NV% is 67.59%. The specific test and calculation results are listed in Table 2.
[0075] Resin sample acid value, solid content and measured data in the embodiment 2 of table 2
[0076]
[0077] It can be obtained that the hydroxyl values measured three times for the resin sample in this embodiment are 22.43, 22.16, and 22.53 respectively, and the average value thereof is 22.37. Therefore, the hydroxyl value of the commercially available unsaturated polyester is 22.37.
Embodiment 3
[0079]This example also provides a method for measuring the hydroxyl value of the resin. The specific steps are the same as in Example 1, except that the selected resin samples are different, and the esterification reactant used is 1,6-hexamethylene diisocyanate (HDI) , the concentration of hydrochloric acid standard solution is C HCl =0.2088mol / L. In this example, a commercial saturated polyester is selected, its hydroxyl value ranges from 55 to 60, its acid value AN is 0.04236 mgKOH / g, and its solid content NV% is 59.99%. The specific test and calculation results are listed in Table 3.
[0080] Resin sample acid value, solid content and measured data in the embodiment 3 of table 3
[0081]
[0082] Thus, the three measured hydroxyl values of the resin sample in this embodiment are 56.71, 56.30, and 56.42 respectively, and the average value is 56.48. Therefore, the hydroxyl value of the commercially available saturated polyester is 56.48.
PUM
| Property | Measurement | Unit |
|---|---|---|
| acid value | aaaaa | aaaaa |
| acid value | aaaaa | aaaaa |
| acid value | aaaaa | aaaaa |
Abstract
Description
Claims
Application Information
Login to View More