1200+ physical-chemical studies were performed and submitted to the regulatory authorities. The physical-chemical testing at our facility includes the following studies:
Physical State OPPTS 830.6303, Color - OPPTS 830.6302 , and Odor - OPPTS 830.6304
The physical state, color and the odour at 20 °C of the test item will be described by conventional terms.
OECD 102 - Melting / Freezing Point
The transition from solid to liquid phase takes place over temperature range. Therefore, the term "melting range" is often used and, in practice, the temperatures of the initial and final stages of melting are determined. For freezing Point, A sample of the substance is placed in a test tube and stirred continuously. As the sample is cooled, its temperature is measured at regular intervals. As soon as the temperature remains constant for a few readings (corrected for thermometer error), this temperature is recorded as the freezing temperature.
OECD 103 - Boiling Point
A sample is heated gradually in boiling test tube which is immersed in a liquid bath. The sample tube is held in close contact with a thermometer and it contains a boiling capillary which is fused about 1cm above its lower end. Upon approach of the boiling temperature bubbles emerge rapidly from the lower open end of the capillary. The boiling temperature is that temperature at which, at momentary cooling, the string of bubbles stops, and liquid suddenly rises in the capillary.
OECD 104 - Vapour Pressure
The Vapour Pressure gives an indication of the probability of the phase transitions liquid/gas and solid/gas. Vapour pressure data is required as a pre-requisite for animal as well as environmental studies. The purpose of the study is to determine the vapour pressure of the test item using the isothermal thermogravimetrical effusion method. The evaporation rates of the test item at elevated temperatures and ambient pressure are determined by monitoring the weight loss. This method is suitable for substances with vapour pressures as low as 1-10 Pa (10-12 mbar) and with purity as close as possible to 100% to avoid the misinterpretation of measured weight losses. It is useful to have preliminary information on the melting point/melting range of the substance before performing these tests.
OECD 105, CIPAC MT 157 - Water Solubility
This guideline addresses the determination of the solubility in water of essentially pure substances which are stable in water and not volatile. The water solubility of a substance can be considerably affected by the presence of impurities. Before determining water solubility, it is useful to have some preliminary information on the substance, like structural formula, vapour pressure, dissociation constant and hydrolysis as a function of pH. Two methods, the column elution method and the flask method are used to determine solubility.
OECD 107- Partition Coefficient by Shake Flask Method
The purpose of the test is to determine experimental value of the partition coefficient (n-octanol/water) when its logarithm is between -2 and 4 and sometimes 5. It is important to carry out the study at a temperature between 20°C and 25°C held constant. Three tests are carried out with different n-octanol/water percentages. The test vessels are prepared in duplicate for each of the three tests with measured quantities of the two solvents and the stock solution. The two phases are then usually separated by centrifugation after stirring. It is important to determine the concentrations of the test item in the two phases by analytical methods that may be suitable for test.
OECD 109, CIPAC MT 3, CIPAC MT 186 - Specific Gravity, Density and Bulk Density
The density is calculated from the difference in weight between the full and empty pycnometer and its volume.
For bulk density, a known weight of solid material is placed in a glass measuring cylinder and its volume is measured to determine pour density.Tap density is obtain by mechanically tapping in graduated measuring cylinder containing solid sample.
OECD 111 - Hydrolysis as a Function of pH
The experiments are performed to determine (i) the rate of hydrolysis of the test substance as a function of pH and (ii) the identity or nature and rates of formation and decline of hydrolysis products to which organisms may be exposed.
OECD 114 - Viscosity of Liquids
Viscosity measurements are carried out predominantly according to following principles : The flow under gravity through a capillary (capillary viscometer or flow cup) Dynamic viscosity can be measured by movement of a ball in a vertical or inclined liquid-filled cylindrical tube.
OECD 115 - Surface Tension of Aqueous Solutions
The purpose of the study is to evaluate the surface tension of an aqueous solution by means of a ring tensiometer at 20 °C. The methods are based on the measurement of the force which it is necessary to exert vertically on a stirrup or ring, in contact with the surface of the liquid, in order to separate it from the surface, or on a plate, with an edge in contact with the surface, in order to draw up the film that has formed.
OECD 117 - Partition Coefficient by HPLC Method
The guideline describes a relatively quick method of estimating the octanol-water partition coefficient (log Pow) of a test item by employing high performance liquid chromatography (HPLC). The reverse phase HPLC technique uses analytical columns filled with silica phase grafted with long hydrocarbon chains. The chemicals are thus retained in the column in proportion to their hydrocarbon/water partition coefficient. The log Pow is determined from a correlation between the retention time (specifically, “log k,” or, ”capacity factor”) and the known log Pow for a series of reference substances. The n-octanol/water partition ratio or coefficient is a key parameter in environmental risk assessment of chemicals and is used in a variety of calculations and models to estimate the environmental fate and bioavailability (and thus exposure) and toxicity of a test item.
OECD 122, CIPAC MT 75.3 - pH
This test guideline describes the procedure for the electrometric determination of pH of an undiluted aqueous solution or dispersion; the pH of 1% (w/v) dilution of a solution or dispersion in distilled or de-ionised water; or the pH of a chemical, diluted to end-use concentration.
ASTM - D93 and ISO 13736:2013 - Flash Point
“Flash point” is the minimum temperature at which a liquid gives off vapor within a test vessel in sufficient concentration to form an ignitable mixture with the air near the surface of the liquid. The lower the flash point, the easier it is to ignite a liquid solvent. These test method are applicable for the detection of contamination of relatively nonvolatile or nonflammable materials with volatile or flammable materials. These test methods should be used to measure and describe the properties of materials, products, or assemblies in response to heat and an ignition source under controlled laboratory conditions.
ASTM STP447B - Particle Size Distribution
This test procedure is applicable to solid test items to determine the particle size by dry sieving method to determine cumulative mass distribution.
EU A9 and A10 - Flammability
The test procedure is applicable to solid or liquid substances, which, in small amounts, will ignite spontaneously for a short time after coming into contact with air at room temperature .this is useful to determine explosive properties of the test item.
EU A21 and A17 - Oxidizing Properties
these test procedures are applicable for both solids and liquids by mixing the test item with suitable comustible substance in various ratios. Each mixture is then formed into a pile and the pile is ignited at once. The maximum burning rate determined is compared with the maximum burning rate of the reference mixture.
