Standard Test Method for Estimating Package Stability of Coatings for Ultraviolet Curing

SIGNIFICANCE AND USE
Coatings intended to be cured by ultraviolet radiation, especially those involving free radical chemistry, tend to polymerize during storage. It is of interest to determine how well a formulation resists this effect. Many factors influence the storage stability of a composition. The procedures described here are intended to improve the precision of determining this property. Because the effects of resins, monomers, photoinitiators, synergists, stabilizers, or pigments can alter the relation between elevated and room temperature stabilities, any correlation of performance at two different temperatures is possible only with a given formulation and, therefore, is useful only for quality control.
SCOPE
1.1 This method covers procedures for testing the package stability of coatings intended to be cured by ultraviolet radiation. One procedure is given for clear coatings and another for opaque fillers.
1.2 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.
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
14-May-2005
Current Stage
Ref Project

Relations

Buy Standard

Standard
ASTM D4144-94(2005) - Standard Test Method for Estimating Package Stability of Coatings for Ultraviolet Curing
English language
2 pages
sale 15% off
Preview
sale 15% off
Preview

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NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.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:D4144–94(Reapproved2005)
Standard Test Method for
Estimating Package Stability of Coatings for Ultraviolet
Curing
This standard is issued under the fixed designation D4144; 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 (´) indicates an editorial change since the last revision or reapproval.
1. Scope relation between elevated and room temperature stabilities, any
correlation of performance at two different temperatures is
1.1 This method covers procedures for testing the package
possible only with a given formulation and, therefore, is useful
stability of coatings intended to be cured by ultraviolet
only for quality control.
radiation. One procedure is given for clear coatings and
another for opaque fillers.
4. Apparatus
1.2 The values stated in SI units are to be regarded as the
4.1 Oven, maintained at 50 6 2°C.
standard. The values given in parentheses are for information
4.2 Glass Jars, wide-mouth, 115-mL (4-oz), with 38-mm
only.
closures.
1.3 This standard does not purport to address all of the
4.3 Cans, lined, 115-mL (4-oz), friction top, with lids.
safety concerns, if any, associated with its use. It is the
4.4 Spheres, glass or porcelain, 7 to 10-mm diameter.
responsibility of the user of this standard to establish appro-
priate safety and health practices and determine the applica-
5. Procedure
bility of regulatory limitations prior to use.
5.1 Clear Coatings:
2. Summary of Method 5.1.1 Fill three 115-mL (4-oz) wide-mouth jars to 6 mm ( ⁄4
in.) from the top.Add a small glass or porcelain sphere to each
2.1 Specimens are placed in several containers, some of
container and put the lids on tightly.
which are subjected to an elevated temperature while others are
5.1.1.1 The amount of head space in a jar or can is critical
stored at room temperature.At specified intervals a specimen is
because the volume of air in contact with the sample has an
checked for evidence of gelling. Clear materials are held in
effect on the rate of polymerization.The stability is also related
glass containers so they can be examined visually without
to the ratio of the area of liquid-air interface to the volume of
opening to prevent contact with air which might inhibit
liquid.
polymerization. Opaque materials are checked by opening one
5.1.2 Put two jars in an oven at 50 6 2°C. Retain the third
can, probing the contents with a spatula to determine the extent
at a temperature, 25 6 2°C, and in the dark.
of any polymerization, and then discarding that specimen.
5.1.3 Check an oven jar daily but do not open or invert.
3. Significance and Use Rather, tip slightly, no more than 30°, to determine the extent
of polymerization by noting the mobility of the sphere. When
3.1 Coatings intended to be cured by ultraviolet radiation,
gelling is noticed, check the second jar to confirm.
especially those involving free radical chemistry, tend to
5.1.4 Record the duration of the test in days. Indicate the
polymerize during storage. It is of interest to determine how
last day the sphere is mobile followed by the first day it is
well a formulation resists this effect. Many factors influence
immobile, and if the days are not consecutive, why the interval
the storage stability of a composition. The procedures de-
occurred.
scribed here are intended to improve the precision of deter-
5.1.5 Check the jar stored at room temperature every week
mining this property. Because the effects of resins, monomers,
but do not open or invert. Tip slightly, no more than 30°, to
photoinitiators, synergists, stabilizers, or pigments can alter the
determine if the sphere is immobile.
5.1.6 Record the number of weeks not gelled followed by
This test method is under the jurisdiction of ASTM Committee D01 on Paint
the first week the sphere is immobile.
and Related Coatings,
...

Questions, Comments and Discussion

Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.