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CD/K/08:2014

ICS

© EAS 2014 First Edition 2014

CD-K-8:2014

ICS

DRAFT EAST AFRICAN STANDARD

Thinner for acrylic resin based auto-refinishing paint - specification

EAST AFRICAN COMMUNITY

CD/K/08:2014

ii © EAC 2014 – All rights reserved

Copyright notice

This EAC document is copyright-protected by EAC. While the reproduction of this document by participants in the EAC standards development process is permitted without prior permission from EAC, neither this document nor any extract from it may be reproduced, stored or transmitted in any form for any other purpose without prior written permission from EAC.

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Web: www.eac-quality.net

Reproduction for sales purposes may be subject to royalty payments or a licensing agreement. Violators may be persecuted

CD/K/08:2014

© EAC 2014 – All rights reserved iii

Contents Page

1. Forward 5 2. Introduction 6 3. Scope 8 4. Normatives references 8 5. Requirements 9 6. Packiging 10 7. Marking 10

8. Annex A (Normative) : Determination of flash point 12

10. Annex B (Normative ) : Determination of flash point 25

13. Annex C (Normative) : Determination of specific gravity at 20 oC 29

14. Annex D (Normative): Determination of specific gravity at 20 oC 31

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iv © EAC 2014 – All rights reserved

Foreword Development of the East African Standards has been necessitated by the need for harmonizing requirements governing quality of products and services in the East African Community. It is envisaged that through harmonized standardization, trade barriers that are encountered when goods and services are exchanged within the Community will be removed.

In order to achieve this objective, the Community established an East African Standards Committee mandated to develop and issue East African Standards.

The Committee is composed of representatives of the National Standards Bodies in Partner States, together with the representatives from the private sectors and consumer organizations. Draft East African Standards are circulated to stakeholders through the National Standards Bodies in the Partner States. The comments received are discussed and incorporated before finalization of standards, in accordance with the procedures of the Community.

East African Standards are subject to review, to keep pace with technological advances. Users of the East African Standards are therefore expected to ensure that they always have the latest versions of the standards they are implementing. This Draft East African Standard, DEAS CD/K/08:2014, was prepared by Technical Committee EASC/TC 70, Paints, Varnishes and related products. The Committee is composed of representatives from National Standards Bodies, regulators and academia, together with the representatives from the private sector and consumer organizations in Partner States.

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© EAC 2014 – All rights reserved v

Introduction

A paint thinner is a solvent used to thin oil-based paints in preparation of the product for use. It is also in cleanning up after their use. The solvents used as paint thinners include:

• Mineral spirits (US) / White spirit (UK)

• Acetone

• Mineral turpentine (turps)

• True turpentine

• Naphtha

• Methyl ethyl ketone (MEK)

• Dimethylformamide (DMF)

• 2-Butoxyethanol, or any of the other glycol ethers

Other solvents sometimes used in the production of paint thinners include:[1]

• Ethylbenzene

• Xylene

• n-butyl acetate

• Butan-1-ol

It is recommanded to be carefully while painting or making the paint of proper consistency by addition of thinner liquid, because there is an exposure to the vapours which can be harmfull for the human health.

The thinner which concerned by this standard is proper for acrylic resin based auto-refinishing paint. It consists of organic liquids only, and shall be clear and free from sediments. The requirements for this standard are intended to render efficient its use in order to satisfy the users and comply with the environment standards.

http://en.wikipedia.org/wiki/Solvent

http://en.wikipedia.org/wiki/Oil_paint

http://en.wikipedia.org/wiki/Mineral_spirits

http://en.wikipedia.org/wiki/White_spirit

http://en.wikipedia.org/wiki/Acetone

http://en.wikipedia.org/wiki/Mineral_turpentine

http://en.wikipedia.org/wiki/Turpentine

http://en.wikipedia.org/wiki/Naphtha

http://en.wikipedia.org/wiki/Methyl_ethyl_ketone

http://en.wikipedia.org/wiki/Dimethylformamide

http://en.wikipedia.org/wiki/2-Butoxyethanol

http://en.wikipedia.org/wiki/Glycol_ethers

http://en.wikipedia.org/wiki/Paint_thinner#cite_note-1

http://en.wikipedia.org/wiki/Ethylbenzene

http://en.wikipedia.org/wiki/Xylene

http://en.wikipedia.org/wiki/N-butyl_acetate

http://en.wikipedia.org/wiki/Butan-1-ol

DRAFT EAST AFRICAN STANDARD CD/K/08:2014

© EAC 2014 – All rights reserved 1

Thinner for acrylic resin based auto-refinishing paint —Specification

1 Scope

This Draft East African Standard specifies requirements, sampling and methods of test for thinner for acrylic resin based auto-refinishing paint.

2 Normative references

1. ISO 115710:2002, Paints and varnishes – corrosion testing by alternate immersion in and removal from a buffered sodium chloride solution

2. ISO 1524 : 2003, Paints, Varnishes and printing inks – Determination of fineness of grind

3. ISO 3251 : 2008, Paints , varnishes and plastics – Determination of non - volatile matter content

4. ISO 9117-3 : 2010, Paints and varnishes – Drying tests – Part 3 : Surface drying test using ballotini.

5. ISO 2813 : 1994, Paints and varnishes – Determination of specular gloss of non – metallic paint films

at 20 degrees, 60 degrees and 85 degrees

6. ISO 6504 :- 3 : 2006, Paints and vanishes – Determination of hiding power – Part 3 : Determination of

contrast ratio of light – coloured paints at a fixed spreading rate.

7. ISO 7253, Paints and varnishes — Determination of resistance to neutral slate spray

8. ISO 2810, Paints and varnishes — Natural weathering of coatings — Exposure and assessment

9. KS 161, Methods of test for paints, varnishes, lacquers and enamels Part 15, Determination of resistance to neutral salt spray (corrosion test)

10. ISO 16474-3:2013, Paints and varnishes -- Methods of exposure to laboratory light sources -- Part 3: Fluorescent UV lamps

11. KS 1027 , Auto refinishing paints — Specification, Part 1: Synthetic resin based

12. KS 03-161:, Methods of test for paints, varnishes, lacquers and enamels, Part 6. Measurement of specular gloss for non-metallic paint films.

13. ISO 15184, Paints and varnishes -— Determination of film hardness by pencil test.

14. ISO 3856 – 1 : 1984, Paints and varnishes – Part 1 : Determination of lead content – Flame atomic

absorption spectrometric method and dithizone spectrophotometric method.

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2 © EAC 2014 – All rights reserved

15. ISO 3668:1998, Paints and varnishes -- Visual comparison of the colour of paints

16. ISO 8130 – 14 : 2004, Coating powders – Part 14 : Terminology

3 Requirements

3.1 General requirements

3.1.1 The thinner shall consist of organic liquids only, and shall be clear and free from sediments and suspended matter. It shall have no objectionable odour.

3.1.2 Toxicity

It shall be free from toxic solvents like benzene and chlorinated hydrocarbons when tested as prescribed in annex A

3.1.3 Compatibility

When the paint based on acrylic resin is thinned in the ratio of 1:4 with the thinner, the mixed material shall be smooth and uniform. It shall not show the tendency of breakdown, coagulation or precipitation of the paint.

2.2 Specific requirements

The thinner shall also comply with the requirements given in Table 1.

Table 1 — Requirements for thinner

SL No. Characteristic Requirement Test method

i) Colour

Not darker than a freshly prepared solution of 0.003 g of K2Cr2O7 in 1 litre of distilled water.

ISO 3668 : 1998

ii)

Odour

Shall have no appreciable odour after drying on a filter paper for 1 h.

(Olfactorial) ISO 16000-28

iii)

Spot test

Shall show complete evaporation from a Whatman filter paper 42 without leaving a stain or only spot after 1 h.

(Visual) ISO 9514 :2005

iv) Relative density 20/20 oC min. 0.850 Annex C

CD/K/08:2014


SL No. Characteristic Requirement Test method

v)

Distillation:

(a) Initial boiling point

oC, min.

(b) Dry point oC, max.

120

180

Annex B

vi) Residual on vaporization, mg/100 mL, max.

5 Annex D

vii) Copper corrosion Shall not blacken or corrode clean

metallic copper ISO 115710 :2002,

viii) Flash point 24.0 oC, min. Annex A

a Specification for thinner for nitrocellulose resin based paints and lacquers.

3 Sampling

3.1 Representative samples of bulk supplies shall be drawn as prescribed in ISO b 15528 from the market or elsewhere and tested for compliance to the standard.

4 Packaging and marking

4.1 Packaging

Thinners for synthetic resin based auto-refinishing paints shall be packaged in suitable containers that will not affect the quality of the product.

4.2 Marking

Thinners for auto-refinishing paints shall be labelled legibly and indelibly with the following:

CD/K/08:2014


a) The words, ‘thinner for acrylic resin auto-refinishing paint or acrylic thinner’

b) Manufacturer’s name and/or registered trademark;

c) Date of manufacture.

d) Net content

e) Batch/code number

f) The words: ‘Inflammable liquid’;

g) Country of manufacture and country of origin

h) Expiry date or best before date

i) Instructions for use, storage and disposal

CD/K/08:2014

© EAC 2014 – All rights reserved

Annex A

(normative)

Determination of flash point

A.1 Summary of test method

A.1.1 A brass test cup of specified dimensions, filled to the inside mark with test specimen and fitted with a cover of specified dimensions, is heated and the specimen stirred at specified rates. An ignition source is directed into the test cup at regular intervals with simultaneous interruption of the stirring, until a flash is detected. The flash point shall be 40 oC minimum

A.2 Significance and use

A.2.1 The flash point temperature is one measure of the tendency of the test specimen to form a flammable mixture with air under controlled laboratory conditions. It is only one of a number of properties which must be considered in assessing the overall flammability hazard of a material.

A.2.2 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 and should not be used to describe or appraise the fire hazard or fire risk of materials, products, or assemblies under actual fire conditions. However, results ofthese test methods may be used as elements of a fire risk assessment which takes into account all of the factors which are pertinent to an assessment of the fire hazard of a particular end use.

A.2.3 These test methods provide the only closed cup flash point test procedures for temperatures up to 370 °C (698 °F).

A.3 Apparatus

A.3.1 Pensky-Martens closed cup apparatus (manual)

This apparatus consists of the test cup, test cover and shutter, stirring device, heating source, ignition source device, air bath, and top plate described in detail in Clause H.10. The assembled manual apparatus, test cup,


test cup cover, and test cup assembly are illustrated in Figures. A1.1-A1.4, respectively. Dimensions are listed respectively.

A.3.2 Pensky-Martens closed cup apparatus (automated)

This apparatus is an automated flash point instrument that is capable of performing the test in accordance with Clause H.7 (Procedure A) and Clause H.8 (Procedure B) of these test methods. The apparatus shall use the test cup, test cover and shutter, stirring device, heating source, and ignition source device described in detail in Clause H.10.

A.3.3 Temperature measuring device

Thermometer or an electronic temperature measuring device, such as resistance thermometers or thermocouples. The device shall exhibit the same temperature response as the mercury thermometers.

A.3.4 Ignition source

Natural gas flame, bottled gas flame, and electric igniters (hot wire) have been found acceptable for use as the ignition source. The gas flame device described in detailed in Figure A.1.4 requires the use of the pilot flame described in Clause H.10. The electric igniters shall be of the hot-wire type and shall position the heated section of the igniter in the aperture of the test cover in the same manner as the gas flame device.

WARNING — Gas pressure supplied to the apparatus should not be allowed to exceed 3 kPa (12 in.) of water pressure.

A.3.5 Barometer, with accuracy of 60.5 kPa.

NOTE The barometric pressure used in this calculation is the ambient pressure for the laboratory at the time of the test. Many aneroid barometers, such as those used at weather stations and airports, are precorrected to give sea level readings and would not give the correct reading for this test.

A.4 Reagents and materials

A.4.1 Cleaning solvents


Use suitable solvent capable of cleaning out the specimen from the test cup and drying the test cup and cover. Some commonly used solvents are toluene and acetone.

WARNING — Toluene, acetone, and many solvents are flammable and a health hazard. Dispose of solvents and waste material in accordance with local regulations.

A.5 Sampling

Successive test specimens can be taken from the same sample container. Erroneously high flash points may be obtained if precautions are not taken to avoid the loss of volatile material. Do not open containers unnecessarily, to prevent loss of volatile material or possible introduction of moisture, or both. Samples for storage shall be capped tightly with inner seals. Do not make a transfer unless the sample temperature is at least the equivalent of 18°C or 32°F below the expected flash point. Do not store samples in gas-permeable containers, since volatile material may diffuse through the walls of the enclosure. Samples in leaky containers are suspect and not a source of valid results.

NOTE Volatile vapors can escape during heating when the sample container is not properly sealed.

A.6 Preparation of apparatus

A.6.1 Support the manual or automated apparatus on a level steady surface, such as a table.

A.6.2 Tests are to be performed in a draft-free room or compartment. Tests made in a laboratory hood or in any location where drafts occur are not reliable.

NOTE 1 A shield, of the approximate dimensions 460 mm (18 in.) square and 610 mm (24 in.) high, or other suitable dimensions, and having an open front is recommended to prevent drafts from disturbing the vapors above the test cup.

NOTE 2 With some samples whose vapors or products of pyrolysis are objectionable, it is permissible to place the apparatus along with a draft shield in a ventilation hood, the draft of which is adjustable so that vapors can be withdrawn without causing air currents over the test cup during the ignition source application period.

A.6.3 Prepare the manual apparatus or the automated apparatus for operation in accordance with the manufacturer’s instructions for calibrating, checking, and operating the equipment.

WARNING — Gas pressure should not be allowed to exceed 3 kPa (12 in.) of water pressure.


A.6.4 Thoroughly clean and dry all parts of the test cup and its accessories before starting the test, to ensure the removal of any solvent which had been used to clean the apparatus. Use suitable solvent capable of removing all of the specimen from the test cup and drying the test cup and cover. Some commonly used solvents are toluene and acetone.

WARNING — Toluene, acetone, and many solvents are flammable health hazard.

A.7 Procedure A

A.7.1 Manual apparatus

Fill the test cup with the test specimen to the filling mark inside of the test cup. The temperature of the test cup and test specimen shall be at least 18°C or 32°F below the expected flash point. If too much test specimen has been added to the test cup, remove the excess using a syringe or similar device for withdrawal of fluid. Place the test cover on the test cup and place the assembly into the apparatus. Be sure the locating or locking device is properly engaged. If the temperature measuring device is not already in place, insert the device into its holder. Light the test flame, and adjust it to a diameter of 3.2 to 4.8 mm (0.126 to 0.189 in.), or switch on the electric igniter and adjust the intensity in accordance with the manufacturer’s instructions.

WARNING — Gas pressure should not be allowed to exceed 3 kPa (12 in.) of water pressure.

WARNING — Exercise care when using a gas test flame. If it should be extinguished it will not ignite the vapors in the test cup, and the gas for the test flame that then enters the vapor space can influence the result.

WARNING — The operator should exercise and take appropriate safety precautions during the initial application of the ignition source, since test specimens containing low-flash material can give an abnormally strong flash when the ignition source is first applied.

WARNING — The operator should exercise and take appropriate safety precautions during the performance of these test methods. The temperatures attained during these test methods, up to 370°C (698°F), are considered hazardous. Apply the heat at such a rate that the temperature, as indicated by the temperature measuring device, increases 5 to 6°C (9 to 11°F)/min. Turn the stirring device at 90 to 120 rpm, stirring in a downward direction.

WARNING — Meticulous attention to all details relating to the ignition source, size of test flame or intensity of the electric igniter, rate of temperature increase, and rate of dipping the ignition source into the vapor of the test specimen is desirable for good results.

A.7.1.1 Application of ignition source

a) If the test specimen is expected to have a flash point of 110 °C or 230 °F or below, apply the ignition source when the temperature of the test specimen is 23 + 5 °C or 41 + 9 °F below the expected flash point and each time thereafter at a temperature reading that is a multiple of 1 °C or 2 °F. Discontinue the stirring of the test specimen and apply the ignition source by operating the mechanism on the test


cover which controls the shutter so that the ignition source is lowered into the vapor space of the test cup in 0.5 s, left in its lowered position for 1 s, and quickly raised to its upward position.

b) If the test specimen is expected to have a flash point above 110 °C or 230 °F, apply the ignition source in the manner described above at each temperature increase of 2°C or 5°F, beginning at a temperature of 23 + 5 °C or 41 + 9 °F below the expected flash point.

WARNING — As a safety practice, when using automated apparatus, it is strongly advised that, for an expected flash point above 130 °C, to dip the igniter every 10 °C throughout the test until the sample temperature reaches 28 °C below the expected flash point and then follow the prescribed dipping procedure. This practice has been shown to reduce the possibility of a fire, and, on average, not to significantly affect the result. A limited study has shown that this dipping practice has no observable effect on test method repeatability.

When testing materials to determine if volatile material contamination is present, it is not necessary to adhere to the temperature limits for initial ignition source application as stated above in a) and b)

When testing materials where the expected flash point temperature is not known, bring the material to be tested and the tester to a temperature of 15 + 5 °C or 60 + 10 °F.

NOTE Flash Point results determined in an “unknown expected flash point mode” should be considered approximate. This value can be used as the expected flash point when a fresh specimen is tested in the standard mode of operation.

Record as the observed flash point the reading on the temperature measuring device at the time ignition source application causes a distinct flash in the interior of the test cup. The sample is deemed to have flashed when a large flame appears and instantaneously propagates itself over the entire surface of the test specimen.

When the ignition source is a test flame, the application of the test flame may cause a blue halo or an enlarged flame prior to the actual flash point. This is not a flash and shall be ignored. When a flash point is detected on the first application, the test shall be discontinued, the result discarded, and the test repeated with a fresh test specimen. The first application of the ignition source with the fresh test specimen shall be 23 + 5°C or 41 + 9°F below the temperature at which a flash point was detected on the first application. When a flash point is detected at a temperature which is greater than 28°C or 50°F above the temperature of the first application of the ignition source, or when a flash point is detected at a temperature which is less than 18°C or 32°F above the temperature of the first application of the ignition source, the result shall be considered approximate, and the test repeated with a fresh test specimen. Adjust the expected flash point for this next test to the temperature of the approximate result. The first application of the ignition source with the fresh test specimen shall be 23 + 5 °C or 416 + °F below the temperature at which the approximate result was found.

When the apparatus has cooled down to a safe handling temperature, less than 55 °C (130 °F), remove the test cover and the test cup and clean the apparatus as recommended by the manufacturer.


NOTE Exercise care when cleaning and positioning the lid assembly so not to damage or dislocate the flash detection system or temperature measuring device. See the manufacturer’s instructions for proper care and maintenance.

A.7.2 Automated apparatus

The automated apparatus shall be capable of performing the procedure as described in H.7.1, including control of the heating rate, stirring of the test specimen, application of the ignition source, detection of the flash point, and recording the flash point.

A.7.2.1 Start the automated apparatus in accordance with the manufacturer’s instructions. WARNING —Failure to install the sample temperature measuring device correctly, when using automated apparatus, can result in uncontrolled heating of the test portion and potentially a fire. Some automated apparatus include provisions to avoid this occurrence. The apparatus shall follow the procedural details described in H.7.1

A.8 Procedure B

A.8.1 Manual apparatus

Fill the test cup with the test specimen to the filling mark inside of the test cup. The temperature of the test cup and test specimen shall be at least 18°C or 32°F below the expected flash point. If too much test specimen has been added to the test cup, remove the excess using a syringe or similar device for withdrawal of fluid. Place the test cover on the test cup and place the assembly into the apparatus. Be sure the locating or locking device is properly engaged. If the temperature measuring device is not already in place, insert the device into its holder. Light the test flame and adjust it to a diameter of 3.2 to 4.8 mm (0.126 to 0.189 in.), or switch on the electric igniter and adjust the intensity in accordance with the manufacturer’s instructions. WARNING — Gas pressure should not be allowed to exceed 3 kPa (12 in.) of water pressure. WARNING — Exercise care when using a gas test flame. If it should be extinguished it will not ignite the vapors in the test cup and the gas for the test flame that then enters the vapor space can influence the result. WARNING — The operator should exercise and take appropriate safety precautions during the initial application of the ignition source, since test specimens containing low-flash material may give an abnormally strong flash when the ignition source is first applied. WARNING — The operator should exercise and take appropriate safety precautions during the performance of these test methods. The temperatures attained during these test methods, up to 370°C (698°F), are considered hazardous.) Turn the stirring device at 250 +10 rpm, stirring in a downward direction. Apply the heat at such a rate that the temperature as indicated by the temperature measuring device increases 1 to 1.6°C (2 to 3°F)/min. Proceed as prescribed in H 7, with the exception of the preceding requirements for rates of stirring and heating.

A.8.2 Automated apparatus

The automated apparatus shall be capable of performing the procedure as described in H.8.1, including control of the heating rate, stirring of the test specimen, application of the ignition source, detection of the flash point, and recording the flash point. Start the automated apparatus in accordance with the manufacturer’s instructions. The apparatus shall follow the procedural details in accordance with H.8.1 above.


A.9 Precision, calculation, and report for procedures A and B

A.9.1 Calculation

Observe and record the ambient barometric pressure (see Note H 3.5) at the time of the test. When the pressure differs from 101.3 kPa (760 mm Hg), correct the flash point as follows:

Corrected flash point C+ 0.25 (101.3 – K) (1)

Corrected flash point F + 0.06 (760 – P) (2)

Corrected flash point C + 0.033 (760 – P) (3)

where:

C = observed flash point, °C,

F = observed flash point, °F,

P = ambient barometric pressure, mm Hg, and

K = ambient barometric pressure, kPa.

After correction for barometric pressure, round the temperature to the nearest 0.5°C (1°F) and record.

A.9.2 Report

A.9.2.1 Report the corrected flash point as Procedure A or Procedure B Pensky-Martens Closed Cup Flash Point of the test specimen.

A.9.3 Precision and Bias (Procedure A)


Precision — The precision of this procedure as determined by the statistical examination of the interlaboratory test results, is as follows:

Repeatability — The difference between successive results, obtained by the same operator with the same apparatus under constant operating conditions on identical test material, would in the long run, in the normal and correct operation of the test method, exceed the following values in 1 case in 20.

r = AX, (4)

A = 0.029,

X = mean result in °C, and

r = repeatability.

Reproducibility — The difference between two single and independent results, obtained by different operators working in different laboratories on identical material, would in the long run, in the normal and correct operation of the test method, exceed the following values only in 1 case in 20.

R =BX, (5)

B = 0.071,

X = mean result in °C, and

R = reproducibility.

Bias — Since there is no accepted reference material suitable for determining the bias for the procedure in these test methods, bias has not been determined.

Relative bias — Statistical evaluation of the data did not detect any significant difference between the reproducibility variances of manual and automated Pensky-Martens flash point results for the samples studied. Evaluation of the data did not detect any significant difference between averages of manual and automated Pensky-Martens flash point for the samples studied with the exception of cycle oil and fuel oil which showed some bias. In any case of dispute, the manual procedure shall be considered the referee test.

NOTE: The precision statements were derived on clear liquids only.


A.9.3 Precision and bias (Procedure B)

Precision — The precision of this procedure, as determined by the statistical examination of the interlaboratory test results, is as follows:

Repeatability — The difference between successive results obtained by the same operator with the same apparatus under constant operating conditions on identical test materials would, in the long run, in the normal and correct operation of the test method, exceed the following value in 1 case in 20:

Residual fuel oil 2°C

Other types 5°C

Reproducibility — The difference between two single and independent results obtained by different operators working in different laboratories on identical material would, in thelong run, exceed the following value only in 1 case in 20:

Residual fuel oil 6°C

Other types 10°C

NOTE The precisions of these standards were derived from interlaboratory studies conducted in the C–scale using C–scale measuring devices.

Bias — Since there is no accepted reference material suitable for determining the bias for the procedure in these test methods, bias has not been determined.

NOTE Procedure B was not tested in the 1991 interlaboratory program.

A.10 Apparatus specifications

A typical assembly of the apparatus, gas heated, is shown in Figure A.1.1. The apparatus shall consist of a test cup, cover, and stove conforming to the following requirements:

Cup — The cup shall be of brass, or other nonrusting metal of equivalent heat conductivity, and shall conform to the dimensional requirements in Figure. A.1.2. The flange shall be equipped with devices for locating the


position of the cup in the stove. A handle attached to the flange of the cup is a desirable accessory. The handle shall not be so heavy as to tip over the

empty cup.

Cover:

Cover Proper —T he cover shown in Figure A.1.3 shall be of brass and shall have a rim projecting downward almost to the flange of the cup. The rim shall fit the outside of the cup with a clearance not exceeding 0.36 mm (0.014 in.) on the diameter. There shall be a locating or locking device, or both, engaging with a corresponding device on the cup. The four openings in the cover, A, B, C, and D, are shown in Figure A.1.3. The upper edge of the cup shall be in close contact with the inner face of the cover throughout its circumference.


Shutter — The cover shall be equipped with a brass shutter (Figures A.1.1 and A.1.4), approximately 2.4 mm (3⁄32 in.) thick, operating on the plane of the upper surface of the cover. The shutter shall be so shaped and mounted that it rotates on the axis of the horizontal center of the cover between two stops, so placed, that when in one extreme position, theshutter shall exactly close the three openings. When operated to the other extreme, the three cover openings shall be exactly open and the tip of the exposure tube shall be fully depressed.

Flame-Ignition Device — The flame-ignition device (Figure A.1.4) shall have a tip with an opening 0.69 to 0.79 mm (0.027 to 0.031 in.) in diameter. This tip shall be made preferably of stainless steel, although it may be fabricated of other suitable metals. The flame-exposure device shall be equipped with an operating mechanism which, when the shutter is in the open position, depresses the tip so that the center of the orifice is between the planes of the under and upper surfaces of the cover proper at a point on a radius passing through the center of the larger opening A (Fig. A1.3). An electric igniter is also suitable. The electric igniters shall be of the electric resistance (hot-wire) type and shall position the heated section of the igniter in the aperture of the test cover in the same manner as the gas flame device.

Pilot Flame — A pilot flame shall be provided for automatic relighting of the exposure flame. A bead 4 mm (5⁄32 in.) in diameter can be mounted on the cover so that the size of the test flame can be regulated by comparison. The tip of the pilot flame shall have an opening the same size as the tip of the flame exposure device (0.69 to 0.79 mm (0.027 to 0.031 in.) in diameter).

Stirring Device — The cover shall be equipped with a stirring device (Figure A.1.4) mounted in the center of the cover and carrying two 2-bladed metal propellers. In Figure A.1.4 lower propeller is designated by the letters L, M, and N. This propeller shall measure approximately 38 mm from tip to tip, with each of its two blades 8 mm in width with a pitch of 45°. The upper propeller is designated by the letters A, C, and G. This propeller measures approximately 19 mm, tip to tip, each of its two blades is also 8 mm in width with a pitch of 45°. Both propellers are located on the stirrer shaft in such a manner that, when viewed from the bottom of the stirrer, the blades of one propeller are at 0 and 180° while the blades of the other propeller are at 90 and 270°. A stirrer shaft may be coupled to the motor by a flexible shaft or a suitable arrangement of pulleys.

Stove — Heat shall be supplied to the cup by means of a properly designed stove which is equivalent to an air bath. The stove shall consist of an air bath and a top plate on which the flange of the cup rests.

Air Bath — The air bath shall have a cylindrical interior and shall conform to the dimensional requirements in Figure A.1.1. The air bath may be either a flame or electrically heated metal casting, or an electric-resistance element (E.10). In either case, the air bath must be suitable for use at the temperatures to which it will be subjected without deformation.

Heater, Flame or Electric — If the heating element is a flame or an electric heater, it shall be so designed and used that the temperatures of the bottom and the walls are approximately the same. In order that the air bath internal surfaces should be at a uniform temperature, it should not be less than 6.4 mm (1⁄4 in.) in thickness unless the heating element is designed to give equal heat flux densities over all the wall and bottom surfaces.

Heater, Electric Resistance — If the heater is of the electric resistance type, it shall be constructed so that all parts of the interior surface are heated uniformly. The wall andbottom of the air bath shall not be less than 6.4


mm (1⁄4 in.) in thickness unless the resistance heating elements are distributed over at least 80 % of the wall and all the bottom of the air bath.A heater having such a distribution of the heating elements positioned at least 4.0 mm (5⁄32 in.) away from the internal surface of the heating unit can be used in conjunction with a

minimum thickness of 1.58 mm (1⁄16 in.) for the wall and bottom of the air bath.

Top Plate — The top plate shall be of metal, and shall be mounted with an air gap between it and the air bath. It may be attached to the air bath by means of three screws and spacing bushings. The bushings should be of proper thickness to define an air gap of 4.8 mm (3⁄16 in.), and they shall be not more than 9.5 mm (3⁄8 in.) in diameter.


Annex B

(normative)

Distillation range

B.1 Definitions

B.1.1 Initial boiling point

The temperature indicated by the distillation thermometer at the instant the first drop of condensate leave the condenser tube.

B.1.2 Dry point

The temperature indicated at the instant the last drop of liquid evaporates from the lowest point in the distillation flask, disregarding any liquid on the side of the flask.

B.2 Summary of the method

A 100 mL specimen is distilled under conditions equivalent to a simple batch differential distillation. The temperature of the mercury in the thermometer is equilibrated with that of the refluxing liquid before the distillate is taken over. Boiling temperatures observed on a partial immersion thermometer are corrected to standard atmospheric pressure to give true boiling temperatures.


B.3 Apparatus

B.3.1 Distillation apparatus

B.3.2 Distillation flasks

200 mL of borosilicate glass.

NOTE Liquid superheating in a new flask may be prevented by depositing a small amount of carbon in the bottom of the flask. This may be accomplished by heating and decomposing a pinch of tartaric acid in the bottom of the flask. The flask is then prepared for use by washing with water, rinsing with acetone, and drying.

B.3.3 Source of heat

An adjustable gas burner/electric heater so constructed that sufficient heat can be obtained to distill the product at the uniform rate specified (see Note 1) for narrow range (less than 2 oC). An electric heater may be used only if it has been proven to give results comparable to those obtained using gas heat.

B.3.4 Receiver

A 100 mL cylinder graduated in 1 ml subdivisions and having an overall height of 250 mm to 260 mm.

B.3.5 Thermometers

Partial immersion type of the range –5 oC to 300 oC with subdivisions of 1 oC. Both bore corrections and either ice or steam standardization corrections are recommended.

B.4 Safety precautions


B.4.1 Most organic solvents and chemical intermediates will burn. In the operation of the distillation apparatus, use a suitable catch pan and shielding to contain spilled liquid in the event of accidental breakage of the distillation flask.

B.5 Preparation of apparatus

B.5.1 Clean and dry the condenser tub by swabbing with a piece of soft lint-free cloth attached to a wire or cord or by any other suitable means.

B.5.2 Center the thermometer into the neck of the flask through a tight fitting cork stopper so that the upper end of the bulb is level with the lower side of the vapour tube at its junction with the neck of the flask.

NOTE It is far more important that the greatest volume of mercury be immersed in the refluxing zone than that the immersion mark on the thermometer be placed at any specific point.

B5.3 Insert the vapour tube of the distillation flask into the condenser, making a tight connection with a well-rolled cork. Adjust the position of the heater shield board so that the neck of the flask is vertical and the vapour tube extends into the condenser tube a distance of 25 mm to 50 mm. Have the bottom of the flask resting firmly in the 32 mm opening of the upper heat resistant board.

B.6 Procedure


B.6.1 Using the graduated receiver, measure 100 mL ± 0.5 mL of the temperature adjusted sample. Remove the flask from the apparatus and transfer the specimen directly to the flask, allowing the graduate to drain for 15 s to 20 s.

B.6.2 Connect the flask to the condenser and insert the thermometer as described in A.5.2. Place the receiver, without drying, at the outlet of the condenser tube in such a position that the condenser tube extends into the graduate at least 25 mm but does not extend below the 100 ml mark. Place a flat cover on the top of the graduate to prevent the condensed moisture from entering the graduate.

B.6.3 Adjust the heat input so that the distillation proceeds at a rate of 4 to 5 mL/min (approximately) 2 drops per second and move the receiving cylinder so that the tip of the condenser tube touches one side of the cylinder after the first drop falls (initial boiling point). Record the readings of the distillation thermometer after collecting 5 mL, 10 mL, 20 mL, 30 mL, 40 mL, 50 mL, 60 mL, 70 mL, 80 mL, 90 mL and 95 mL of distillate.

B.6.4 Without changing the heater setting, continue distillation beyond 95 per cent point unit until the dry point is observed (A.1.3). If dry point is not obtained (that is, if active decomposition should occur before the dry point is reached as evidenced by rapid evolution of vapour or heavy fumes; or if there is a liquid remaining on the bottom of the flask when the maximum temperature is observed on the distillation thermometer), record this fact.

B.6.5 When the dry point cannot be obtained, report as the end point, the maximum temperature observed on the distillation thermometer. When active decomposition is encountered, the rapid evolution of vapour and heavy fumes is usually followed by a gradual decrease in the distillation temperature. If the expected drop in temperature does not occur, record the maximum temperature observed on the distillation thermometer after the 95 per cent point has been reached, and report as end point, 5 minimum. This notation shows that a true end point could not be reached within the given time limit. In any event, the end point should not exceed 5 minimum after the 95 per cent point.

B.6.7 Record the barometric pressure

B.6.8 Barometric correction

Correct each reading for deviation of the barometric pressure from normal by adding algebraically the correction calculated as follows:


Correction = k (760 - p)

where,

K = rate of change of boiling point with pressure in degrees Celsius per millimetre, and

P = Barometric pressure in millimetres of mercury at standard temperature.

Annex C

(normative)

Determination of specific gravity at 20 oC

C.1 Definition

Specific gravity is the ratio of the mass of a given volume of liquid at 20 oC to the mass of an equal volume of water at the same temperature.

C.2 Apparatus


C.2.1 Hydrometer glass graduated in units of relative density of total range 0.600 to 1.100 with a graduation interval of 0.001.

B.2.2 Thermometers Of total range of –5 to 250 oC with a graduation interval of 0.5.

B.2.3 Hydrometer cylinder Clear glass, or metal. For convenience in pouring, the cylinder may have a lip on the rim. The inside diameter of the cylinder shall be at least 25 mm greater than the outside diameter of the hydrometer used in it. The height of the cylinder shall be such that the hydrometer floats in the sample with at least 25 mm clearance between the bottom of the hydrometer and the bottom of the cylinder.

C.2.4 Constant-temperature bath, for use when the sample requires a test temperature much above or below room temperature.

C.3 Procedure

.3.1 Adjust the temperature of the sample to 20 oC and bring the hydrometer cylinder and thermometer to approximately the same temperature.

C.3.2 Transfer the sample to a clean hydrometer cylinder without splashing to avoid formation of bubble. Remove any air bubbles formed, after they have collected on the surface of the sample, by touching them with a piece of clean filter paper before inserting the hydrometer.

C.3.3 Place the cylinder containing the sample in a vertical position in a location free from air currents. Ensure that the temperature of the sample does not change appreciably during the time necessary to complete the test; during this period, the temperature of the surrounding should not change by 2 oC. When testing at temperatures above room temperature a constant temperature bath may be necessary to avoid excessive temperature changes.

C.3.4 Lower the hydrometer gently into the sample. Take care to avoid wetting the stem above the level to which it will be immersed in the liquid. Continuously stir the sample with the thermometer taking care that the mercury thread is kept fully immersed and that the stem of the hydrometer is not wetted above the immersion level. As soon as a steady reading is obtained, record the temperature of the sample to the nearest 0.25 oC and then remove the thermometer.


C.3.5 Depress the hydrometer about two scale divisions into the liquid, and then release it. The remainder of the stem of the hydrometer, which is above the level of the liquid, must be kept dry since unnecessary liquid on the stem affects the reading obtained. With samples of low viscosity, impart a slight spin to the hydrometer on releasing to assist in bringing it to rest, floating freely away from the walls of the cylinder. Allow sufficient time for the hydrometer to come to rest, and for all air bubbles to come to the surface. This is particularly necessary in case of more viscous samples.

C.3.6 When the hydrometer has come to rest, floating freely away from the walls of the cylinder, estimate the hydrometer scale reading to the nearest 0.000 1 relative density. The correct hydrometer reading is that point on the hydrometer scale at which the principal surface of the liquid cuts the scale. Determine this point by placing the eye slightly below the level of the liquid and slowly raising it until the surface first seen as distorted eclipse, appears to become a straight line cutting the hydrometer scale.

Annex D

(normative)

Determination of residue on evaporation

D.1 Note : Residue on evaporation: The amount of nonvolatile residue obtained under the conditions of test.


D.2 Apparatus

D.2.1 Evaporation bath, either a solid metal-block bath using a metal of high thermal conductivity, or a liquid bath fitted with a reflux condenser, electrically heated and constructed in accordance with the general principles shown in Figure F.1. The electric supply to the liquid bath shall be sufficient to keep the Liquid boiling through the preheating coil at the specified rate. The evaporation bath shall be provided with wells and air jets for three or more beakers and be insulated. The preheaters, manifolds, and air outlets shall be so constructed as to allow the required rate of air flow (see Clause E.2.2). The beaker wells shall be made sufficiently deep to allow insertion of the 100 ml beakers to a depth of 70 mm. If a liquid bath is used, it shall be filled to within 25 mm of the top with a stable liquid having a boiling point within 160o C and 165o C; (ethylene glycol) containing approximately 3 per cent of water is suitable for this purpose.

D.2.2 Air supply apparatus, capable of supplying filtered air at a pressure not greater than 34.5 kN/m2 (0.35 kgf/cm2) to the inlet of the preheating coil of the bath, and at a rate sufficient to provide a flow from each outlet of 1 000 ± 150 ml/s at a temperature of 155± 5o C.

D.2.3 Flowmeter, capable of metering a flow of air equivalent to 1 000 ml/s for each outlet of the evaporation bath at the operating temperature. The use of a calibrated flowmeter allowing a flow of 600 ± 90 ml/s, measured at room temperature, will ensure delivery of 1 sml /90000 ± at the operating temperature, provided that the pressure at the outlet of the flowmeter is not greater than 34.5 kN/m2 (0.35 kgf/cm2).

D.2.4 Beakers, of 100 mL capacity, flat bottomed as shown in Figure F.1. The beakers shall be arranged in sets, the number in each set depending on the number of beaker wells in the evaporation bath

D.2.5 Cooling vessel, suitable covered vessel for cooling the beakers before weighing, such as a glass desiccator or a tightly covered metal vessel for each set of beakers. A drying agent is not to be used in the cooling vessel.

D.2.6 Balance, having a sensitivity of at least 0.1 mg, preferably with no drying agent in the case.

D.2.7 Thermometer, of the mercury-in-glass type, nitrogen-filled, graduated on the stem, enamel-baked, adjusted for 76 mm immersion and allowing temperature in the range 150 oC to 160 oC to be measured with an accuracy of ± 1 oC at an average temperature of the mergent mercury column of 65 oC (see note on A.5.2).

D.3 Cleaning liquids


D.3.1 A mixture of equal volumes of toluene and acetone, of analytical reagent quality.

D.3.2 Chromic/sulphuric acid solution.

D.4 Preparation of apparatus

D.4.1 Assemble the apparatus as shown in Figure F.1. With the apparatus at room temperature, adjust the air flow to a rate of 600 mL/s at one of the outlets. Measure the flow at the remaining outlets and make any necessary adjustments so that the rate at each outlet is 600± 90 mL/s (see E.2.3). Heat the bath and when its temperature reaches 160o C to 165o C, place a beaker in each well (E.2.1). Submit air at the rate required with the conical jets in position. Check the temperature in each well by placing the bulb of the thermometer on the bottom of the beaker in the well. Do not use any well where the temperature does not lie between 150 oC and 160 oC.

D.4.2 Clean new beakers by immersion in the chromic/sulphuric acid solution (E.3.2) for at least 6 h. Remove the beakers from the solution by means of stainless steel forceps and handle only with forceps thereafter. Wash the beakers thoroughly, first with tap water, then with distilled water.

NOTE Protective clothing such as gloves and goggles must be worn by operators using chromic/sulphuric acid solution.

Clean beakers which have been used in previous determinations by removing the residue with the mixture (E.3.1), then immerse them for at least 6 h in chromic/sulphuric acid cleaning solution followed by washing as described above. Clean the tare beakers in a similar manner.

Dry the beaker for 1 h in an oven at 150 oC and allow them to cool for at least 2 h in the cooling vessel placed in the vicinity of the balance.

D.5 Procedure

For each sample, weigh to the nearest 0.1 mg two test beakers for aduplicate determination, using analytical balance. Repeat the weighings without changing the order in which the beakers are weighed, until consecutive masses for the beakers agree within 0.1 mg, and record the masses. If suspended or solid matter is present, mix the contents of the sample container thoroughly. Immediately filter, at atmospheric pressure, the necessary quantity of the sample through a sintered-glass funnel of porosity grade p.100 (pore size index 40 mµ to 100 mµ ).


Using a graduated measuring cylinder, pour 50 ml of the sample into each test beaker. Place the full beakers and also the empty tare beaker in the evaporation bath, previously heated to the specified temperature (160o C to 165o C). Replace the conical jet as each beaker is filled, centering the jet vertically above the surface of the liquid. The time elapsing between filling the first and second beakers shall be as short as possible. Supply air at the required rate.

After 30 min evaporation, remove the beakers from the bath, place them in the cooling vessel and allow to cool in the vicinity of the balance for at least 2 h. Weigh the beakers in the same manner and in the same sequences as was followed previously, repeating the weighings until consecutive masses agree within 0.1 mg. If the results of the two evaporations differ by more than 1.0 mg, repeat the determinations.

D.6 Expression of results

D.6.1 Calculate the residue on evaporation A, in milligrams per 100 mL, by the formula.

A = 2 000 (m1 - mo)

where,

m1 = the mass, in grams, of the test beaker plus residue; and

mo = the mass, in grams, of the empty test beaker.


D.6.2 Report the mean of the sum of the results of the duplicate determinations to thenearest milligram per 100 ml as the residue on evaporation. After the numericalvalue designated by the word ‘filtered’ if the sample has been so treated.

D.7 Precision

For results of the order of 10 mg/100 mL (i.e. the maximum permitted residue), duplicate results shall not be considered suspect unless they differ by more than 3 mg/100 mL (repeatability) or 6 mg/100 mL (reproducibility).

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