Determination for solid content of polyacrylamide
1Key Takeaways
This standard specifies the determination method for the solid content of powdery and colloidal polyacrylamide. This standard applies to the determination of the solid content of powdery and colloidal polyacrylamide produced by different polymerization methods.
2Expert Interpretation
In-depth analysis of GB 12005.2-89 Polyacrylamide solid content determination method, covering the scope of application, determination steps and implementation recommendations. This article comprehensively interprets the content of the standard from technical background to practical application.
National Standard of the People's Republic of China GB 12005.2—89 Determination of Solid Content of Polyacrylamide
This standard specifies the determination method of solid content of powdered and colloidal polyacrylamide, and is applicable to samples produced by different polymerization methods. Solid content is defined as the percentage of solid matter after removing volatiles such as water.
Scope of application of the standard
GB 12005.2—89 standard is applicable to:
- Determination of solid content of powdered polyacrylamide
- Determination of solid content of colloidal polyacrylamide
- Samples produced by different polymerization methods
Determination principle and technical background
Polyacrylamide is a polymer material, and its solid content is an important indicator for measuring product quality. The solid content can be obtained by drying the sample to constant weight under specific temperature and vacuum conditions, and calculating the percentage of the sample mass after drying to the mass before drying.
The determination method is divided into two parts: the direct drying method for powdered samples and the indirect determination method for colloidal samples, which are respectively suitable for samples in different forms.
Instruments and Equipment
The following are the experimental instruments and their technical parameters specified in the standard:
| Instrument name | Specifications and models | Instructions for use |
|---|---|---|
| Weighing bottle | Inner diameter 40 mm, height 30 mm | Used to accurately weigh the sample mass |
| Polyester membrane | Length 120 mm, width 60 mm, thickness 0.1 mm | Used for collecting and weighing colloidal samples |
| Glass rod | Diameter 3~4 mm, length 100~120 mm | Used for sample coating and operation |
| Analytical balance | Sensitivity 0.0001 g | Accurately weigh the sample mass |
| Vacuum oven | Vacuum degree 5300 Pa, adjustable temperature | Used for sample drying |
Determination steps and methods
Powder sample determination steps
- Take three clean weighing bottles and dry them at 105 ± 2 °C to constant weight, and record the mass (accurate to 0.0001 g).
- Weigh 0.6~0.8 g of sample, accurate to 0.0001 g.
- Put the weighing bottle with the sample in a vacuum oven and dry it at 105 ± 2 °C and 5300 Pa vacuum conditions for 4 hours.
- Take out the weighing bottle, weigh it (accurate to 0.0001 g) after cooling for 30 minutes, and calculate the solid content.
Measurement steps of colloidal samples
- Take three polyester films and three glass rods, dry them at 100 ± 2 °C to constant weight, and record the mass (accurate to 0.0001 g).
- Use a glass rod to take 0.4~0.6 g of sample on each polyester film, and weigh it quickly together with the glass rod (accurate to 0.0001 g).
- Evenly spread the sample on the surface of the polyester film.
- Put the coated polyester film and glass rod into a vacuum oven and dry them at 100 ± 2 °C and 5300 Pa for 4 hours.
- Take out the dried sample, cool it for 15 minutes, weigh it (accurate to 0.0001 g), and calculate the solid content.
Result calculation and verification
Solid content percentage calculation formula:
S = (m / m₀) × 100%- m: mass of sample after drying, g
- m₀: mass of sample before drying, g
Three parallel determination values are rounded to two decimal places, and the arithmetic mean is taken as the final result. When the individual measured value of a powder sample deviates from the average value by more than 1%, or when the individual measured value of a colloid sample deviates from the average value by more than s%, resampling is required.
Implementation recommendations
To ensure the accuracy and consistency of the measurement results, it is recommended that:
- Operate strictly in accordance with the temperature and vacuum conditions specified in the standard.
- Choose appropriate instruments and equipment, and calibrate the analytical balance and oven regularly.
- For colloid samples, ensure uniform coating to avoid measurement errors.
- Pay attention to the accuracy of the decimal places when recording experimental data.