N-isopropylacrylamide

Particle size distribution (Granulometry)

Link to relevant study record(s)

Reference

Endpoint:

particle size distribution (granulometry)

Type of information:

experimental study

Adequacy of study:

key study

Study period:

28 November 2017 and 29 November 2017

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

ISO 13320 (Particle size analysis - Laser diffraction methods)

Qualifier:

according to guideline

Guideline:

other: CIPAC MT 187 “Particle Size Analysis by Laser Diffraction”, Handbook K, 2007

GLP compliance:

yes (incl. QA statement)

Type of method:

other: The analysis is conducted initially using a visual microscope and is then undertaken more formally using a Laser Diffraction Particle Size Analyser

Type of particle tested:

other: powder

Specific details on test material used for the study:

Lot Number 2161004
Purity 99.41%
Description White to light yellow flakes, with characteristic odour
Expiry date 31/01/2018

Mass median aerodynamic diameter:

ca. 491.383 µm

Geometric standard deviation:

>= 8.749 - <= 9.459

Key result

Percentile:

D10

Mean:

30.759 µm

St. dev.:

1.319

Key result

Percentile:

D50

Mean:

494.609 µm

St. dev.:

9.761

Key result

Percentile:

D90

Mean:

1 197.05 µm

St. dev.:

22.868

Optical Microscope Analysis

Standard visual observation

Sample observed to be mostly coarse powder with some large flakes also contains some medium and fine particles 

Observation using 3.2 objective lens

The particles appeared to be irregular shaped crystals with some rectangular shaped crystals. The smallest individual particle size was approximately 6 µm and the largest individual size was approximately 2080 µm.

Observation using 40 objective lens

The sample was observed to be made up of single crystalline particles.

Manual Sieve Analysis

Full Test Results

 

Sieve size (µm)	Sieve weight (g)	Sieve + powder weight (g)	Powder weight (g)	% by weight
< 2000	353.7	400.5	46.8	27.7
> 2000	325.9	448.2	122.3	72.3
		TOTALS	169.1	100.0

Solubility And Dispersability Test For Particle Size Analysis

Table of solubility results

Dispersant used : Silicone Oil & Kerosene

		Series 1			Series 2
Silicone Oil
Time elapsed	1 (1.6 mg)	2 (1.5 mg)	3 (1.5 mg)	1 (5.0 mg)	2 (4.9 mg)	3 (5.0 mg)
10 seconds		Welldispersed			Welldispersed
30 minutes		Welldispersed			Welldispersed
60 minutes		Welldispersed			Welldispersed
90 minutes		Welldispersed			Welldispersed
120 minutes		Welldispersed			Welldispersed

Kerosene
Time elapsed	1 (1.5 mg)	2 (1.5 mg)	3 (1.6 mg)	1 (5.0 mg)	2 (4.9 mg)	3 (5.0 mg)
10 seconds		Well dispersed			Welldispersed
30 minutes		Well dispersed			Welldispersed
60 minutes		Well dispersed			Welldispersed
90 minutes		Well dispersed			Welldispersed
120 minutes		Well dispersed			Welldispersed

The sample was sieved < 2000 µm prior to testing to remove coarse particles/flakes (some of the flakes were in the region of 10 - 15 mm in diameter). Sample contained a wide range of particles from fine powder to large flakes. Testing using DPM did not give reproducible results. Testing was then carried out with silicone oil on SVM, this was not picking up the larger particles present in sample. Testing using kerosene as the solvent gave results which matched up with visual  analysis.

 

Comments:          The sample proved to be insoluble, and well dispersed in kerosene.

Kerosene was therefore used as the dispersant.

During the method development phase of the analysis trials were conducted using both the dry powder module (DPM) and the small volume (wet) module (SVM). The SVM trials were conducted using kerosene as the dispersant. The results of these trials indicated that the most appropriate test and material parameters to obtain the optimum measurements  were.

 

Module: SVM

Dispersant: Kerosene

Average Sample Concentration: 1382 % Vol

Dispersion speed: 1500 rpm

Refractive index (sample): 1.500n

Absorption: 0 AU

Analysis Model: General Purpose (Normal)

 

Using the identified parameters, the particle size was analysed over the range 0.02 µm to 2000 µm.

Full Test Results

 

	RUN 1	RUN 2	RUN 3	RUN 4	RUN 5	Average* *
Volume weighted mean	532.296	563.360	546.433	544.717	553.359	548.033
Median	478.374	507.828	498.421	491.484	498.370	494.609
Mode	751.375	819.429	779.471	788.731	812.267	789.551
MMAD *	475.254	504.516	495.171	488.279	495.120	491.383
d10 - 10 % of material is <	31.304	33.199	29.949	29.962	29.676	30.759
d50 - 50 % of material is <	478.374	507.828	498.421	491.484	498.370	494.609
d90 - 90 % of material is <	1160.836	1226.963	1187.100	1193.956	1214.393	1197.050

 

All results are in µm

*Mass median aerodynamic diameter

**Average result is calculated from the entirety of data captured in each run and is not a simple arithmetic mean.

2.45.% by volume of sample was seen to be<10.00 µm.

 

Standard Deviation results

 

Run No.	1	2	3	4	5	STDVP	% STDVP
d10 - 10 % of material is <	31.304	33.199	29.949	29.962	29.676	1.319	4.3
d50 - 50 % of material is <	478.374	507.828	498.421	491.484	498.370	9.761	2.0
d90 - 90 % of material is <	1160.836	1226.963	1187.100	1193.956	1214.393	22.868	1.9
d15.78 - 15.78 % of material is <	54.237	58.041	52.766	52.346	52.685	2.115	3.9
GSD	8.820	8.749	9.446	9.389	9.459	0.318	3.5
MMAD	475.254	504.516	495.171	488.279	495.120	9.697	2.0

 

GSD = Geometric standard deviation of the lognormal particle size distribution (calculated from d50/d15.78) STDVP = standard deviation of the population

% STDVP = percentage standard deviation of the  population

Coefficient of variation for d50 is less than 3%; d10 and d90 are less than 5%. Thus repeatability of the characteristic particles in the size distribution are within the acceptable limits as per the ISO 13320-1 teststandard.

Executive summary:

Particle Size Analysis using small volume (wet) module (SVM)	Average (µm)
Volume weighted mean	548.033
Median (d.50)	494.609
Mode	789.551
MMAD (Mass Median Aerodynamic Diameter)	491.383
10 % of material is <	30.759
50 % of material is <	494.609
90 % of material is <	1197.050
by volume of sample was seen to be < 10.00 µm	2.45 %
Manual sieve analysis indicated that 27.7 % by weight of the sample had a particle size of < 2000 µm.  A subsequent laser diffraction analysis on the < 2000 µm sample produced the results above

Description of key information

Particle Size Analysis using small volume (wet) module (SVM)	Average (µm)
Volume weighted mean	548.033
Median (d.50)	494.609
Mode	789.551
MMAD (Mass Median Aerodynamic Diameter)	491.383
10 % of material is <	30.759
50 % of material is <	494.609
90 % of material is <	1197.050
by volume of sample was seen to be < 10.00 µm	2.45 %
Manual sieve analysis indicated that 27.7 % by weight of the sample had a particle size of < 2000 µm.  A subsequent laser diffraction analysis on the < 2000 µm sample produced the results  above