ASTM F2625-10
(Test Method)Standard Test Method for Measurement of Enthalpy of Fusion, Percent Crystallinity, and Melting Point of Ultra-High-Molecular Weight Polyethylene by Means of Differential Scanning Calorimetry
Standard Test Method for Measurement of Enthalpy of Fusion, Percent Crystallinity, and Melting Point of Ultra-High-Molecular Weight Polyethylene by Means of Differential Scanning Calorimetry
SIGNIFICANCE AND USE
The crystallinity of UHMWPE will influence its mechanical properties, such as creep and stiffness. The reported crystallinity will depend on the integration range used to determine the heat of fusion, and the theoretical heat of fusion of 100 % crystalline polyethylene used to calculate the percent crystallinity in an unknown specimen. Differential scanning calorimetry is an effective means of accurately measuring both heat of fusion and melting temperature.
This test method is useful for both process control and research.
SCOPE
1.1 This test method discusses the measurement of the heat of fusion and the melting point of ultra-high-molecular weight polyethylene (UHMWPE), and the subsequent calculation of the percentage of crystallinity.
1.2 This test method can be used for UHMWPE in powder form, consolidated form, finished product, or a used product. It can also be used for irradiated or chemically-crosslinked UHMWPE.
1.3 This test method does not suggest a desired range of crystallinity or melting points for specific applications.
1.4 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.
1.5 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
Relations
Buy Standard
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NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.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: F2625 − 10
StandardTest Method for
Measurement of Enthalpy of Fusion, Percent Crystallinity,
and Melting Point of Ultra-High-Molecular Weight
1
Polyethylene by Means of Differential Scanning Calorimetry
This standard is issued under the fixed designation F2625; 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 E967 Test Method for Temperature Calibration of Differen-
tial Scanning Calorimeters and Differential Thermal Ana-
1.1 This test method discusses the measurement of the heat
lyzers
of fusion and the melting point of ultra-high-molecular weight
E968 Practice for Heat Flow Calibration of Differential
polyethylene (UHMWPE), and the subsequent calculation of
Scanning Calorimeters
the percentage of crystallinity.
E1953 Practice for Description of Thermal Analysis and
1.2 This test method can be used for UHMWPE in powder
Rheology Apparatus
form, consolidated form, finished product, or a used product. It
can also be used for irradiated or chemically-crosslinked
3. Terminology
UHMWPE.
3.1 Symbols:
1.3 This test method does not suggest a desired range of
3.1.1 ∆H,n—theoretical heat of fusion of 100 % crystalline
f
crystallinity or melting points for specific applications.
material (J/g).
1.4 The values stated in SI units are to be regarded as
3.1.2 ∆H,n—mass normalized heat of fusion of the test
s
standard. No other units of measurement are included in this sample (J/g).
standard.
3.1.3 T,n—melting temperature at the peak of the melting
p
endotherm (°C).
1.5 This standard does not purport to address all of the
safety concerns, if any, associated with its use. It is the
3.1.4 T,n—onset temperature of the melting endotherm
o
responsibility of the user of this standard to establish appro-
(°C).
priate safety and health practices and determine the applica-
3.1.5 %X, n—percentage of crystallinity of material.
bility of regulatory limitations prior to use.
4. Summary of Test Method
2. Referenced Documents
4.1 This test method consists of placing a known mass of
2
2.1 ASTM Standards:
UHMWPE in a sample pan and heating the sample pan at a
D3418 Test Method for Transition Temperatures and En-
controlled temperature while measuring the heat flow to the
thalpies of Fusion and Crystallization of Polymers by
sample pan and an empty reference pan. The area under the
Differential Scanning Calorimetry
melting endotherm, indicative of the enthalpy of melting, is
E691 Practice for Conducting an Interlaboratory Study to
normalized with the sample mass. This value is then normal-
Determine the Precision of a Test Method
ized with the theoretical enthalpy of melting of 100 % crystal-
E793 Test Method for Enthalpies of Fusion and Crystalliza-
linepolyethylenetodeterminethepercentageofcrystallinityin
tion by Differential Scanning Calorimetry
the test sample.
5. Significance and Use
1
This test method is under the jurisdiction ofASTM Committee F04 on Medical
5.1 The crystallinity of UHMWPE will influence its me-
and Surgical Materials and Devices and is the direct responsibility of Subcommittee
chanical properties, such as creep and stiffness. The reported
F04.15 on Material Test Methods.
crystallinity will depend on the integration range used to
Current edition approved Dec. 1, 2010. Published December 2010. Originally
determine the heat of fusion, and the theoretical heat of fusion
approved in 2007. Last previous edition approved in 2007 as F2625 – 07. DOI:
10.1520/F2625-10.
of 100 % crystalline polyethylene used to calculate the percent
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
crystallinity in an unknown specimen. Differential scanning
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
calorimetry is an effective means of accurately measuring both
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. heat of fusion and melting temperature.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1
---------------------- Page: 1 ----------------------
F2625 − 10
5.2 This test method is useful for both process control and standard and the heat of fusion shall be reported and compared
3
research. with published values (T = 156.6°C,∆ H = 28.57 J/g). The
o f
DSC calibration should be verified on at least a monthly basis.
6. Interferences
NOTE 3—The value of the∆H will vary with the lot of the indium by
f
6.1 As machining processes can affect the crystalline struc-
asmuchas3 %.Usersshouldrefertothecertificateofanalysisforthe∆H
f
ture of UHMWPE, care shoul
...
This document is not anASTM standard and is intended only to provide the user of anASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation:F2625–07 Designation:F2625–10
Standard Test Method for
Measurement of Enthalpy of Fusion, Percent Crystallinity,
and Melting Point of Ultra-High-Molecular Weight
1
Polyethylene by Means of Differential Scanning Calorimetry
This standard is issued under the fixed designation F2625; 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
1.1 This test method discusses the measurement of the heat of fusion and the melting point of ultra-high-molecular weight
polyethylene (UHMWPE), and the subsequent calculation of the percentage of crystallinity.
1.2 This test method can be used for UHMWPE in powder form, consolidated form, finished product, or a used product. It can
also be used for irradiated or chemically-crosslinked UHMWPE.
1.3 This test method does not suggest a desired range of crystallinity or melting points for specific applications.
1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
1.5 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.
2. Referenced Documents
2
2.1 ASTM Standards:
D3418 Test Method for Transition Temperatures and Enthalpies of Fusion and Crystallization of Polymers by Differential
Scanning Calorimetry
E691 Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method
E793 Test Method for Enthalpies of Fusion and Crystallization by Differential Scanning Calorimetry
E967 Test Method for Temperature Calibration of Differential Scanning Calorimeters and Differential Thermal Analyzers
E968 Practice for Heat Flow Calibration of Differential Scanning Calorimeters
E1953 Practice for Description of Thermal Analysis and Rheology Apparatus
3. Terminology
3.1 Symbols:
3.1.1 DH , n—theoretical heat of fusion of 100 % crystalline material (J/g).
f
3.1.2 DH , n—mass normalized heat of fusion of the test sample (J/g).
s
3.1.3 T , n—melting temperature at the peak of the melting endotherm (°C).
p
3.1.4 T , n—onset temperature of the melting endotherm (°C).
o
3.1.5 %X, n—percentage of crystallinity of material.
4. Summary of Test Method
4.1 This test method consists of placing a known mass of UHMWPE in a sample pan and heating the sample pan at a controlled
temperature while measuring the heat flow to the sample pan and an empty reference pan. The area under the melting endotherm,
indicative of the enthalpy of melting, is normalized with the sample mass. This value is then normalized with the theoretical
enthalpy of melting of 100 % crystalline polyethylene to determine the percentage of crystallinity in the test sample.
5. Significance and Use
5.1 The crystallinity of UHMWPE will influence its mechanical properties, such as creep and stiffness. The reported
1
This test method is under the jurisdiction of ASTM Committee F04 on Medical and Surgical Materials and Devices and is the direct responsibility of Subcommittee
F04.15 on Material Test Methods.
Current edition approved Feb. 1, 2007. Published February 2007. DOI: 10.1520/F2625-07.
Current edition approved Dec. 1, 2010. Published December 2010. Originally approved in 2007. Last previous edition approved in 2007 as F2625 – 07. DOI:
10.1520/F2625-10.
2
For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at service@astm.org. For Annual Book ofASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
1
---------------------- Page: 1 ----------------------
F2625–10
crystallinity will depend on the integration range used to determine the heat of fusion, and the theoretical heat of fusion of 100 %
crystalline polyethylene used to calculate the percent crystallinity in an unknown specimen. Differential scanning calorimetry is
an effective means of accurately measuring both heat of fusion and melting temperature.
5.2 This test method is useful for both process control and research.
6. Interferences
6.1 As machining processes can
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.