GB 28142-2011Imidacloprid wettable powders (English PDF)

3.1 Composition and appearance

This product should meet the standards of imidacloprid with suitable additives and fillers processing is made uniform loose powder, there should be no lumps.

3.2 Technical Specifications

Imidacloprid WP should meet the requirements of Table 1.

Table 1 imidacloprid WP Control Project Index

project

index

10% 20% 25% 50% 70%

Imidacloprid mass fraction /% 20.0 10.0 1.0 to 1.0 1.5-1.5 1.2-1.2 25.0 50.0 70.0 2.5-2.5 2.5-2.5 pH range 6.0 to 10.0 Wetting time/s <= 90 Fineness (through 45µm test sieve) /% >= 98

Table 1 (continued)

project

index

10% 20% 25% 50% 70%

Suspension rate /% >= 85 Thermal storage stability of a qualified when a normal production of heat storage stability test was measured at least once every three months.

Test Method 4

Safety Tips. Use of this standard shall have practical experience of laboratory personnel work. This standard does not point out all of the safety issues. Make with those who have the responsibility to take appropriate safety and health practices and to ensure compliance with the relevant national regulations.

4.1 General provisions

This standard reagents and water in the absence of other requirements specified, refers to three analytical reagent and GB/T 6682-2008 specified in water. Test results determined in accordance with GB/T 8170-2008 4.3.3 Rounding the value comparison method.

4.2 Sampling

According to GB/T 1605-2001 "on solid preparation sampling" approach. Determining sample package using a random number table method; the final sample size not less than 300g.

4.3 Identification Test

Liquid chromatography --- The identification test can be carried out simultaneously with the determination of the mass fraction of imidacloprid. Under the same chromatographic operating conditions, the test the retention time of the sample solution and the standard solution to a peak of imidacloprid chromatographic retention time, the relative difference should be 1.5% Fewer.

4.4 Determination of the mass fraction of imidacloprid

4.4.1 Method summary

Sample dissolved in mobile phase, methanol and water as the mobile phase, use as filler to C18 stainless steel column and UV detector at a wavelength 260nm, the sample of imidacloprid reverse phase HPLC separation and determination of external standard.

4.4.2 Reagents and solutions

Methanol. HPLC grade;

Water. The new secondary steam distilled water;

Imidacloprid standard. a known mass fraction w>=99.0%.

4.4.3 Instruments

High performance liquid chromatography. a variable wavelength UV detector;

Chromatographic data processor or chromatography workstation;

Column. 250mm × 4.6mm (id) stainless steel column, built C18,5µm filler (or with equivalent effect column);

Filter. pore size of about 0.45µm;

Micro injector. 50µL;

Quantitative sample line. 5µL;

Ultrasonic cleaner.

4.4.4 HPLC operating conditions

Mobile phase. Psi (methanol. water) = 40.60, by membrane filtration, and degassing;

Flow rate. 0.8mL/min;

Column temperature. room temperature (temperature change should not exceed 2 °C);

Detection wavelength. 260nm;

Injection volume. 5µL;

Retention time. about imidacloprid 6.0min.

It said operating parameters are typical, according to the characteristics of different instruments, given operating parameters adjusted as appropriate, in order to obtain the best results.

Typical imidacloprid WP HPLC is shown in Figure 1.

1 --- imidacloprid.

Figure 1 imidacloprid WP High Performance Liquid Chromatographic

4.4.5 Measuring step

4.4.5.1 Preparation of standard solution

Weigh 0.1g (accurate to 0.0002g) imidacloprid standard in 100mL flask with methanol to volume, ultrasonic oscillation 5min make sample dissolution, cooled to room temperature and shake well. Using a pipette to take the above solution 5mL to 50mL volumetric flask, dilute with mobile phase to the mark.

4.4.5.2 Preparation of sample solution

Weigh containing imidacloprid 0.1g (accurate to 0.0002g) sample in 100mL flask with methanol to the mark, the ultrasonic transducer Dang 5min to dissolve the sample was cooled to room temperature and shake well. Using a pipette to take the above solution 5mL to 50mL volumetric flask, with the mobile phase Dilute to the mark.

4.4.5.3 Determination

Under these operating conditions, after the instrument is stable, continuous injection of several doses of the standard solution until the two adjacent needles Imidacloprid peak area relative change After less than 1.2%, according to the solution, the sample solution, the sample solution and standard sequence of the standard solution was measured.

4.4.5.4 Calculation

The two needle sample solution and measured before and after the two doses of the standard sample solution imidacloprid peak areas are averaged. Imidacloprid sample the mass fraction according to equation (1).

A2 · m1 · w

A1 · m2

Where.

w1 --- sample imidacloprid mass fraction, expressed as a percentage;

A2 --- sample solution, imidacloprid mean peak area;

m1 --- imidacloprid standard mass in grams (g);

w --- imidacloprid standard mass fraction, expressed as a percentage;

A1 --- the standard solution, the average peak area imidacloprid;

m2 --- sample mass, in grams (g).

4.4.6 Allowable difference

Imidacloprid content parallel determination of the difference between the results, 10%, 20%, 25% wettable powder should be less than 0.5%; 50%, 70% WP should not exceed 1.0%, and the arithmetic mean as a measurement result.

Determination of 4.5 pH value According to GB/T 1601 carried out.

4.6 Determination of the suspension rate

According to GB/T 14825-2006 4.1 performed. Weigh containing imidacloprid 0.1g sample (accurate to 0.0002g), the remaining 1/10 the suspension and the precipitate was transferred to a 100mL flask with 60mL to 25mL of methanol 3 times all the residue washed into 100mL capacity Flask, under ultrasonic oscillations 5min, cooled to room temperature, constant volume, shake, filter, measuring 4.4 according to the quality of imidacloprid, calculate the hanging Floating rate.

4.7 Determination of wetting time

According to GB/T 5451 carried out.

4.8 Determination of fineness

According to GB/T 16150 in the "wet sieve method".

4.9 Thermal storage stability test

According to GB/T 19136 in "powder formulations" to. After the heat storage imidacloprid content should not be less than 97% of the reservoir before the suspension was still should meet Combined standard requirements for qualified.

4.10 Product inspection and acceptance

Shall comply with GB/T 1604's.

5.1 Marking, labeling, packaging

Imidacloprid WP application aluminized plastic bags or aluminum foil bag, net weight is generally not more than 100g. It can also be used in accordance with User requirements or the order agreement, the use of other forms of packaging, subject to the provisions of GB 3796.

5.2 Storage

Imidacloprid WP package should be stored in well-ventilated, dry coffers. Storage and transportation, to prevent moisture and sunlight, no food, seed Child, feed-mixing, avoid contact with skin, eyes, mouth and nose to prevent inhalation.

5.3 Security

This product is a low toxicity formulation. It can penetrate through the skin. When using this product to avoid contact with skin, use soap and water after application.

Poisoning should immediately sent to hospital symptomatic treatment.

5.4 Warranty Period

Under the specified storage conditions, imidacloprid WP guarantee of two years starting from the date of manufacture.

Appendix A

(Informative)

Other names for imidacloprid, structural formula and basic physicochemical parameters Other name, structural formula and basic physicochemical parameters of the active ingredient imidacloprid product are as follows.

ISO common name. Imidacloprid CAS Registry Number. 138261-41-3 CIPAC Numeric Code. 582 Chemical name. 1- (6-chloro-3-pyridylmethyl) -N- nitromethylene-imidazol-2-yl-amine Structure.

Empirical formula. C9H10ClN5O2 Molecular Weight. 255.7 Biological activity. Insecticidal Melting point. 144 °C Vapor pressure (20 °C). 4 × 10-7mPa Solubility (20 °C, g/L). water 0.61, 0.68 toluene, methylene chloride 55, 1.2 isopropanol, n-hexane is less than 0.1 Stability. pH value of 5 to 11 stable, easy hydrolysis.