ASTM D7029-04

Standard Test Method for Determination of Reactivity of Unsaturated Polyesters and Vinyl Esters at 180.0F [82.2°C]

SCOPE
1.1 This standard provides a standardized test method for determining the gelation and exotherm curve of unsaturated polyester and vinyl ester resins. This method provides guidance for measurement of the "Standard 180°F [82.2°C] Exotherm Curve" along with information on variances of the measurement which may be required for special resins. This test method provides information concerning the reactivity of unsaturated polyester and vinyl ester resins as they go through polymerization after mixing with the initiator.
Note 1—There is no known ISO Equivalent to this standard, although ISO 584 is similar.
1.2 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in nonconformance with the standard.
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

General Information

• Status: Historical
• Publication Date: 30-Apr-2004
• ICS: 71.080.70 - Esters
• Technical Committee: D20 - Plastics
• Drafting Committee: D20.18 - Reinforced Thermosetting Plastics

Relations

• Replaced By: ASTM D7029-09 - Standard Test Method for Determination of Reactivity of Unsaturated Polyesters and Vinyl Esters at 180.0F [82.2°C]
• Effective Date: 01-Sep-2009
• Referred By: ASTM D7745-19 - Standard Practice for Testing Pultruded Composites
• Effective Date: 01-May-2004

Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation:D7029–04
Standard Test Method for
Determination of Reactivity of Unsaturated Polyesters and
Vinyl Esters at 180.0°F [82.2°C]
This standard is issued under the fixed designation D 7029; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (e) indicates an editorial change since the last revision or reapproval.
1. Scope 3.1.1 gel time—the period of time in minutes and seconds
required for the recording pyrometer to go from a temperature
1.1 This standard provides a standardized test method for
below (usually 10 to 30°F or 5.5 to 16°C) bath temperature to
determining the gelation and exotherm curve of unsaturated
10°F [5.55°C] above the bath temperature, typically 150°F
polyester and vinyl ester resins. This method provides guid-
[65.5°C] to 190°F [78.8°C] for a bath at 180°F [82.2°C].
ance for measurement of the “Standard 180°F [82.2°C] Exo-
3.1.2 cure time—the period of time in minutes and seconds
therm Curve” along with information on variances of the
required for the recording pyrometer to go from a temperature
measurement which may be required for special resins. This
below (usually 10 to 30°F or 5.5 to 16°C) bath temperature to
test method provides information concerning the reactivity of
the maximum temperature reading, typically 150°F [65.5°C] to
unsaturated polyester and vinyl ester resins as they go through
the maximum temperature for a bath at 180°F [82.2°C].
polymerization after mixing with the initiator.
3.1.3 interval time—the period of time in minutes and
NOTE 1—There is no known ISO Equivalent to this standard, although
seconds required for the recording pyrometer to go from 10°F
ISO 584 is similar.
[5.5°C] above the bath temperature to the maximum tempera-
1.2 The values stated in either SI units or inch-pound units
ture reading, typically 190°F [78.8°C] to the maximum tem-
are to be regarded separately as standard. The values stated in
perature. Thus, interval time is cure time minus gel time.
each system may not be exact equivalents; therefore, each
3.1.4 peak exotherm—the maximum temperature reached
system shall be used independently of the other. Combining
during the testing.
values from the two systems may result in nonconformance
3.1.5 recording pyrometer—a broad class of temperature
with the standard.
measuring devices including thermocouples with the ability for
1.3 This standard does not purport to address all of the
continuous temperature recording.
safety concerns, if any, associated with its use. It is the
3.1.6 initiator—a compound that generates free radicals to
responsibility of the user of this standard to establish appro-
start the free radical polymerization of the unsaturated polyes-
priate safety and health practices and determine the applica-
ter and vinyl ester resins. It is typically a peroxide.
bility of regulatory limitations prior to use.
4. Summary of Test Method
2. Referenced Documents
4.1 Polyester or vinyl ester resin is mixed with the initiator
2.1 Society of Plastics Industry, Inc.:
in a beaker causing a polymerization of the resin to occur. Heat
Handbook of Reinforced Plastics “Procedure for Running
will accelerate the polymerization reaction. The exotherm
Exotherm Curves Using the Block Test Method”
generated by the resin as it cures is measured using a
2.2 ISO Standard:
thermocouple. The curve is plotted and the time to reach
ISO 584 Reinforced Plastics Based on Unsaturated Polyes-
various temperatures along with the peak temperature obtained
ter Resins—Determination of Reactivity at 80°C
(peak exotherm) is determined. The initiator normally em-
ployedtogeneratethetestresultsisbenzoylperoxide,although
3. Terminology
the method may be used with other initiator systems.
3.1 Definitions:
4.2 Thetestmethodisusefulinprovidinginformationabout
the heat generated during cure of the resin and the length of
time the resin remains in the liquid state prior to polymeriza-
This test method is under the jurisdiction ofASTM Committee D20 on Plastics
tion into solid form.
and is the direct responsibility of Subcommittee D20.18 on Reinforced Thermoset-
ting Plastics.
Current edition approved May 1, 2004. Published June 2004.
Available from American National Standards Institute (ANSI), 25 W. 43rd St.,
4th Floor, New York, NY 10036.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
D7029–04
5. Significance and Use L] an shall be fitted with a cover with access holes for the bath
heater, thermometer, and test tubes in order to minimize
5.1 This test method is used to measure the reactivity of
evaporation of water.
different lots of unsaturated polyester and vinyl ester resins.
7.4 Borosilicate Glass Test Tubes, of 19 mm diameter and
The information provided by this test can be used for assessing
150 mm length with plain end and lip.
the predicted performance of a resin when used in elevated
temperature as part of the process used to convert the resin into
7.5 “Type J” Thermocouple Needle, made from 304 stain-
a finished product.
less steel, 6 in. [152 mm] in length, with an outside diameter of
5.2 The method is used in research and development by
⁄8 in. [3.2 mm] connected to a “Type J” Jack Assembly or
companies that manufacture resins and for incoming quality
equivalent.
control companies using these polymers as raw materials for
7.6 “Type J” Double Conductor, B&S Gauge wire with
production. The method is based on the methods which were
poly insulation and color coding (white for positive/red for
previously outlined in the Handbook of Reinforced Plastics,
negative) to connect “Type J” thermocouple needle to record-
“Procedure for Running Exotherm Curves Using the Block
ing pyrometer or equivalent.
Test Method” published by the Society of the Plastics Industry.
7.7 Electronic Balance, suitable for accurate weighing to
0.01 g and a minimum capacity of 200 g.
6. Interferences
7.8 Machined Centering Device, for centering thermo-
6.1 The results obtained can be influenced by the type of
couple needle within the resin sample. This device may be
resin used, the age of the resin, the age of the initiator and the
made from reinforced plastics, micarta, or other suitable
type of initiator used. Care shall be taken to assure that the
material. See Fig. 1 for the set up of the device.
chemicals used are stored and used in accordance with the
7.9 Beaker (150 mL), made of glass or plastic.
manufacturers’ guidelines.
6.2 Control of the bath temperature and the circulation
8. Reagents and Materials
within the bath can affect the results of the test. Care shall be
taken to control the bath temperature and agitation to comply
8.1 Styrene Monomer, with 15 6 5 ppm of Tertiary Butyl
with the method instructions.
Catechol (TBC) Inhibitor.
8.2 Initiator Type:
7. Apparatus
8.2.1 Type I—98 % Benzoyl Peroxide crystals.
7.1 Recording Pyrometer, Iron Constantan, 60 in. [1.5 m]
8.2.2 Type II—Benzoyl Peroxide paste/emulsion with a
per hour charts speed or equivalent.
tolerance of 6 1.5 % of the specified concentration with a
7.2 Thermometer, with divisions every 0.1°F [0.05°C] ca-
maximum of 18 % water. Example: 40 % benzoyl peroxide
pable of reading a minimum of 180 6 1°F [82.2 6 0.5°C] or
with a range of concentration from 38.5 to 41.5 %.
equivalent.
8.2.3 Type III—Initiator(s) mutually agreed upon by labo-
7.3 Constant Temperature Water Bath, or alternate media
ratories running the test.
bathcapableofbeingcontrolledto180 60.5°F[82.2 60.2°C]
8.3 Unsaturated Polyester and Vinyl Ester Resin.
with an agitation rate of 1 to 2 times the bath capacity per
minute.The bath shall have a minimum capacity of 2.5 gal [8.8 8.4 Silicone Grease.
FIG. 1 Machine Centering Device for Thermocouple Assembly
D7029–04
9. Hazards 14.7 Immerse the test tube in the 180°F [82.2°C] constant
temperature bath so the level of liquid in the test tube is below
9.1 Initiators such as benzoyl peroxide must be stored in
the surface of the liquid in the bath and start the recording
accordance with manufacturers’ guidelines. Failure to do so
pyrometer.
can result in the materials becoming unstable causing fire or
14.8 When the peak exotherm temperature is reached, let
explosions.
thetemperaturebegintodropandremovethetesttubefromthe
9.2 Directly mixing metals like cobalt and other chemical
bath. Remove the test probe from the resin and test tube.
with the initiators can create explosive conditions.
15. Calculation or Interpretation of Results
10. Test Results
15.1 Unless otherwise specified the following values
...