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2 PYCNOMETRIC POWDER (PP) DATA SHEET Catalog No. : 5110 Material : Ground Silica Appearance : Off-white translucent coarse powder Lot No. : 4805 Tapped Density*: g/ml (2.77 sigma) Test Conditions: Cylinder 1 : 250 ml No. of taps 2 : 2000 Tap rate 3 : /min Tap height 4 : mm 5 (1/8 ) Sample mass 6 : g 7 (or approximately 235 ml) Other Data*: Hausner Ratio 8 (HR): 1.07 ± 0.03 (2.77 sigma) Notes V HR = 0 V f V 0 = initial (untapped) volume V f = final (tapped) volume Carr s Compressibility Index 9 (CI): 6.14% ± 2.25% (2.77 sigma) CI = ( V V ) 0 V 0 f 100% V 0 = initial (untapped) volume V f = final (tapped) volume 1. Shall conform to the following minimum specifications: ASTM E1272 class B. 2. This has been found to be more than sufficient to attain constant volume for this material. 3. Quantachrome instruments tap at a nominal 260 taps/min. Above specification based on BP (Appendix VXII D.) and ISO (787 part 11) standards. 4. Quantachrome instruments are shipped with nominal drop height 1/8 unless specified for 3mm mm falls within specification for most metric standards. 5. Drop height for specific instrument used (ser no ) in the development of this data sheet was measured to be 3.11mm using NIST traceable pin gauge no Sample weights used in the development of this data sheet were obtained using NIST traceably calibrated, electronic balance serial number , trace number FL Balance used should have a readability of 0.1g or better. Multiple part-weighings of the test powder may be necessary on balances with less than total sample mass capacity. 8. H.H. Hausner, Int J Powder Metall. 3 (1967) See also USP General Test Chapter <616>. 9. R.L. Carr, Chem Eng. 72 (1965) See also USP General Test Chapter <616>. * Special Note: The values reported on this Data Sheet represent measurements on the sample as received DS &RUSRUDWH'ULYH%R\QWRQ%HDFK)/86$7HO)D[

3 PYCNOMETRIC POWDER (PP) INSTRUCTION SHEET Introduction Quantachrome PP s are provided to aid in installation, validation and verification of Quantachrome s tap density analyzers, and for the determination of envelope (geometric) density of irregularly shaped particles and coarse powders. They were characterized on Quantachrome tap density analyzers. Safety Pycnometric Powders are safe for use by trained personnel under normal laboratory conditions. Consult the appropriate Material Safety Data Sheet (MSDS) for details. Storage/Sampling Be certain to store in a sealed container. During transit of powdered samples, segregation can occur. For this reason it is recommended that the entire contents be re-mixed prior to use for maximum accuracy. Instrument Readiness Please confirm the proper calibration of the equipment to be used. Sample Preparation No special preparation is necessary PPRM

4 MATERIAL SAFETY DATA SHEET SECTION I Product Name: PP110 Manufacturer s Information Name: Quantachrome Instruments Street: 1900 Corporate Drive City, State, ZIP: Boynton Beach FL Country: USA Tel: (800) Tel: (561) Fax: (561) SECTION II Ingredients Composition: Ground Silica CAS No.: SECTION III Physical/Chemical Data Appearance: White powder. Odor: None. Solubility in water: Insoluble. Specific gravity: 2.5 SECTION IV Flash-point: Extinguishing media: Fire fighting procedure: Unusual fire and explosion hazards: SECTION V Stability: Incompatibility: Fire & Explosion Hazard Data Not flammable. Appropriate for surrounding fire. Protect from nuisance dust. None. Reactivity Data Inert. Hydrofluoric and phosphoric acids, concentrated alkaline solutions.

5 SECTION VI Exposure route: Acute and chronic health hazards: Carcinogen: Symptoms of exposure: Medical conditions aggravated: Emergency first aid: Health Hazard Data Inhalation of dust. Repeated or prolonged inhalation of dust may result in irritation to the respiratory tract. Not listed by OSHA or NTP. Nuisance dust may cause eye and respiratory irritation. Chronic respiratory conditions may be aggravated by exposure to high concentrations of dust.. Remove to fresh air if nuisance dust. Flush eyes with copious amounts of water. SECTION VII Storage conditions: Handling precautions: Intended use: Storage, Handling & Use No special conditions necessary. Minimize generation of dust, transport in closed containers. Pycnometric powder. SECTION VIII Control methods: Waste disposal: Spill Control Sweep or vacuum up material for disposal, do not generate dust. Follow local, state or federal guidelines for disposal of inert solid waste. Material contaminated in use may require special precautions. SECTION IX Respiratory: Eyes: SECTION X Median particle size: Ecological information: Special Protection Dust control measures or NIOSH/MSHA approved respirator. Safety glasses with side shields or goggles are recommended. Other Data c. 110 um No specific information available. Glass is normally recognized as a non-hazardous material and routinely disposed of in non-hazardous waste (landfill) sites. Reasonable care has been taken in the preparation of this MSDS from sources believed to be reliable. Quantachrome Instruments extends no warranties nor responsibilities regarding its use. March 26, Revised May 3,

6 POWDER TECH NOTE 24 GEOMETRIC (Envelope) DENSITY WITHOUT MERCURY One of the most common density measurements involves the determination of the geometric space occupied within the envelope of a solid material, including any interior voids, cracks or pores. This is called geometric, envelope or bulk density. And only equals true density when there are no internal openings in the material being measured. If the material has a uniform rectilinear or spherical shape, the volume it occupies can be calculated from measurements by caliper or ruler. However, a great majority of measurements involve complex shapes in formed materials such as ceramics, powder metals, molded polymers and granulated or pelleted products. In this case, the unknown volume may be determined by immersing it in liquid and measuring the volume of liquid displaced, which is the Archimedes principle. TAP DENSITY Each particle of a solid material has the same true density after grinding, milling or processing, but more geometric space is occupied by the material. In other words, the geometric density is less, approaching 50% less than true density if the particles are spherical. Handling or vibration of powdered material causes the smaller particles to work their way into the spaces between the larger particles. The geometric space occupied by the powder decreases and its density increases. Ultimately, no further natural particle packing can be measured without the addition of pressure. Maximum particle packing is achieved. For decades*, liquid mercury has been used to measure geometric (envelope) density because its non-wetting nature prevents its entry into small voids. However, if there are problems with mercury amalgamation, safe handling or disposal facilities, liquids such as hot wax**, oil, kerosene or water have been used. In the latter case, the sample is usually coated with a polymer spray to seal openings and an appropriate correction is made in each measurement. Under controlled conditions of tap rate, tap force (fall) and cylinder diameter, the condition of maximum packing efficiency is highly reproducible. This tap density measurement is formalized in the British Pharmacopoeia method for the Apparent Volume, ISO 787/11 and ASTM standard test methods B527, D1464 and D4781 for tap density. (Over) *ASTM C **ASTM B Corporate Drive Boynton Beach, FL USA (800) (561) Fax (561) (Page 1 of 2)

7 POWDER TECH NOTE 24 POWDER PYCNOMETRY At ambient pressure, only voids in solid materials greater than 14.5 µm can be penetrated by mercury. That being the case, a free flowing powder having a narrow particle size distribution centering on 14.5 µm will enter or be excluded from cylindrical, slit, wedge, slit/wedge and constricted (ink bottle) openings in much the same manner as liquid mercury. MATERIALS Quantachrome provides a particle size reference material, PP 14, a pycnometric powder that is well suited to be employed as described above. Automated tap density determinations are performed either by the Quantachrome Autotap or two sample Dual Autotap. These units accept standard graduated cylinders from 10 to 1000 ml. During tapping, cylinder rotation helps to maintain a level powder surface for accurate readings. Automatic operation is controlled by a preset number of taps up to Both tap units conform to the tap density standards cited herein. Further, if the pycnometric powder has a known tap density, the volume displaced by the unknown sample is easily calculated from the tap density of the combination of a pycnometric powder reference + unknown sample. V p = V mix + [V mi x V 0 ] (m 0 /m s ) Where: V p = geometric (envelope) volume, unknown [cc/g] V mix = sum of volumes, reference + unknown [cc/g] V 0 = pycnometric powder volume, reference [cc/g] m 0 = mass of reference [g] m s = mass of unknown [g] This alternative method of powder pycnometry has been demonstrated to agree within <1% with the method of mercury immersion pycnometry 1. Autotap and Dual Autotap [1] C.A. Leon y Leon, et al., A Comparison Between Particle Densities determined by Mercury Displacement and Solid Pycnometry, Powder Technology, submitted (1997) (Page 2 of 2)

8 POWDER TECH NOTE 30 Tapped Density in the Pharmaceutical Industry Both active and inactive (excipient) compounds are used in the manufacture of solid dosage formulations, i.e. tablets and capsules. These powders possess many properties or characteristics and exhibit certain behaviors as a result. One important characteristic is tapped bulk density, or simply tapped (tap) density: that is, the maximum packing density of a powder (or blend of powders) achieved under the influence of well-defined, externally applied forces. The minimum packed volume thus achieved depends on a number of factors including particle size distribution, true density, particle shape and cohesiveness due to surface forces including moisture. Therefore, the tap density of a material can be used to predict both its flow properties and its compressibility (see below as to how). These are just two of the many parameters which are important in the overall tabletting process - which requires that loose powders be compacted into a durable solid form with the correct mechanical strength, porosity and dissolution characteristics and in capsulefilling performance. The two most commonly used measures of the relative importance of interparticulate interactions are the compressibility index (often referred to as Carr s Index 1 ) and the Hausner ratio 2 as follows: where V and D represent powder volume and density respectively, subscript 0 denotes the initial or untapped state and f the final or tapped state. In free-flowing powders the initial bulk and tapped densities will be more similar than in poorly flowing powders which yield greater differences between the two values. The Autotap and two-sample Dual Autotap conform to USP <616> for Tapped Density (Method II). The measuring cylinder containing the powder sample is dropped a height of 3mm (1/8 ) at a rate of approximately 250 drops per minute. Both Autotaps feature a drop counter which can be set to any value from 1 to An optional lock-out mechanism is available to prevent tampering with a preset number of counts. Quantachrome s Autotaps therefore can contribute a vital role in the development and assurance of solid dosage formulations in the pharmaceutical industry. 1 R.L. Carr, Chem Eng. 72 (1965) H.H. Hausner, Int J Powder Metall. 3 (1967) 7-13 Compressibility Index = 100* (V 0 - V f )/V 0 = 100* (D f - D 0 ) / D f and Hausner Ratio = V 0 / V f = D f / D Corporate Drive Boynton Beach, FL USA (800) (561) Fax (561) (Page 1 of 1)