ASTM D5017-96(2009)e1

Standard Test Method for Determination of Linear Low Density Polyethylene (LLDPE) Composition by Carbon-13 Nuclear Magnetic Resonance

SIGNIFICANCE AND USE
Performance properties are dependent on the number and type of short chain branches. This test method permits measurement of these branches for ethylene copolymers with propylene, butene-1, hexene-1, octene-1, and 4-methylpentene-1.
SCOPE
1.1 This test method determines the molar composition of copolymers prepared from ethylene (ethene) and a second alkene-1 monomer. This second monomer can include propene, butene-1, hexene-1, octene-1, and 4-methylpentene-1.  
1.2 Calculations of this test method are valid for products containing units EEXEE, EXEXE, EXXE, EXXXE, and of course EEE where E equals ethene and X equals alkene-1. Copolymers containing a considerable number of alkene-1 blocks (such as, longer blocks than XXX) are outside the scope of this test method.
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.  See Section 8 for a specific hazard statement.  
Note 1—There is no equivalent ISO standard.

General Information

• Status: Historical
• Publication Date: 09-Jun-2003
• ICS: 83.080.20 - Thermoplastic materials
• Technical Committee: D20 - Plastics
• Drafting Committee: D20.70 - Analytical Methods

Relations

• Replaces: ASTM D5017-96(2003)e1 - Standard Test Method for Determination of Linear Low Density Polyethylene (LLDPE) Composition by Carbon-13 Nuclear Magnetic Resonance
• Effective Date: 10-Jun-2003

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NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.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
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Designation: D5017 − 96 (Reapproved 2009)
Standard Test Method for
Determination of Linear Low Density Polyethylene (LLDPE)
Composition by Carbon-13 Nuclear Magnetic Resonance
This standard is issued under the fixed designation D5017; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
ε NOTE—Reapproved with editorial changes in April 2009.
1. Scope System of Units (SI): The Modern System
1.1 This test method determines the molar composition of
3. Terminology
copolymers prepared from ethylene (ethene) and a second
alkene-1monomer.Thissecondmonomercanincludepropene, 3.1 Some units, symbols, and abbreviations used in this test
butene-1, hexene-1, octene-1, and 4-methylpentene-1. method are summarized in IEEE/ASTM SI-10 and Practice
E386. Other abbreviations are listed as follows:
1.2 Calculations of this test method are valid for products
3.2 Abbreviations:
containing units EEXEE, EXEXE, EXXE, EXXXE, and of
3.2.1 C—carbon 13,
course EEE where E equals ethene and X equals alkene-1.
Copolymers containing a considerable number of alkene-1 3.2.2 LLDPE—linear low-density polyethylene,
blocks(suchas,longerblocksthanXXX)areoutsidethescope
3.2.3 T1—relaxation time, and
of this test method.
3.2.4 TR—pulse repetition time.
3.3 Definitions of Terms Specific to This Standard:
1.3 This standard does not purport to address all of the
safety concerns, if any, associated with its use. It is the 3.3.1 With a few modifications, terms used to designate
different carbon types were suggested by Carman. Methine
responsibility of the user of this standard to establish appro-
priate safety and health practices and determine the applica- carbons are identified by CH and branch carbons are labeled
according to branch type as summarized in Table 1. Branch
bility of regulatory limitations prior to use. See Section 8 for a
carbons are numbered starting with the methyl as number one.
specific hazard statement.
3.3.2 Backbone methylene carbons are designated by a pair
NOTE 1—There is no equivalent ISO standard.
ofGreeklettersthatspecifythelocationofthenearestmethine
carbonineachdirection.Forexample,α,α-methylenecarbonis
2. Referenced Documents
+
between two methine carbons or an α,δ methylene carbon has
one immediate methine neighbor and the second methine
2.1 ASTM Standards:
E177Practice for Use of the Terms Precision and Bias in carbon is located at least four carbons away.
ASTM Test Methods
E386Practice for Data Presentation Relating to High- 4. Summary of Test Method
Resolution Nuclear Magnetic Resonance (NMR) Spec-
4.1 Polymer samples are dispersed in hot solvent and
troscopy
analyzed at high temperatures using Carbon-13 nuclear mag-
E691Practice for Conducting an Interlaboratory Study to
netic resonance (NMR) spectroscopy.
Determine the Precision of a Test Method
4.2 Spectra are recorded under conditions such that the
IEEE/ASTM SI-10Standard for Use of the International
response of each chemically different carbon is identical.
Integrated responses for carbons originated from the different
comonomers are used for calculation of the copolymer com-
ThistestmethodisunderthejurisdictionofASTMCommitteeD20onPlastics
position.
and is the direct responsibility of Subcommittee D20.70 on Analytical Methods.
Current edition approved April 1, 2009. Published June 2009. Originally
ε1
approved in 1991. Last previous edition approved in 2003 as D5017–96(2003) .
DOI: 10.1520/D5017-96R09E01.
2 3
For referenced ASTM standards, visit the ASTM website, www.astm.org, or Available from ASTM International Headquarters, 100 Barr Harbor Drive,
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM C700, West Conshohocken, PA 19428.
Standards volume information, refer to the standard’s Document Summary page on Carman,C.J.,Harrington,R.A.,andWilkes,C.E., Macromolecules1977,Vol
the ASTM website. 10, p. 536.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
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D5017 − 96 (2009)
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TABLE 1 Designations for Different Carbon Types
9.8 Pulse width, <[4×sweep width Hz]
Monomer Branch Type Label
9.9 Decoupling, complete
Propene (P) methyl M1
Butene-1 (B) ethyl E1–E2 NOTE6—ThenuclearOverhauserenhancementforthecarbonsusedfor
4, 6, 7
Hexene-1 (H) butyl B1–B4
quantitative analysis have been shown to be full.
4-Methylpentene-1 (MP) isobutyl IB1–IB3
Octene-1 (O) hexyl H1–H6
10. Procedure
10.1 Weigh a 1.2-g sample into a 10-mm NMR tube. Add
1.5 mLof solvent (7.1) and 1.3 mLdeuterated solvent (7.2)to
5. Significance and Use
the tube. Cap the tube.
5.1 Performance properties are dependent on the number
NOTE 7—Solution concentration can be varied with instruments of
and type of short chain branches. This test method permits
different field strength as long as one meets the minimum signal-to-noise
measurement of these branches for ethylene copolymers with
requirement of 9.4.
propylene, butene-1, hexene-1, octene-1, and
10.2 Homogenize the sample in an oven at 150°C for 3 to 4
4-methylpentene-1.
h. Keep the tube in a vertical position during the heating step.
6. Apparatus
10.3 Set spectrometer parameters as detailed in Section 9.
6.1 NMR Spectrometer, C pulse-Fourier transform spec- 10.4 Transfer the tube to the NMR spectrometer and equili-
trometer with a field strength of at least 2.35 T.
brate 10 to 15 min at 130°C.
10.5 Scan the sample with complete broadband decoupling
NOTE 2—The system should have a computer size of at least 32 K for
50-MHz carbon frequency with digital resolution of at least 0.5 Hz/point
using the parameters of Section 9.
in the final spectrum.
10.6 Record the spectrum and the accurate full-scale inte-
6.2 Sample Tubes, 10-mm outside diameter.
gralfrom10to50ppm.Adjustpartialintegralssothatintegral
of the second largest peak in the spectrum is at least 50% of
NOTE 3—Sample tube size can be varied; however, the sample
preparation procedure described in 10.1 may need to be altered to
full-scale.This partial integral must be flat before and after the
maintain the minimum signal-to-noise requirement of 9.4.
area to be measured.
7. Reagents and Materials NOTE 8—The combination of sample preparation time and acquisition
timenecessarytoobtainthesignal-to-noiserequirementof9.4canleadto
7.1 Ortho-dichlorobenzene or 1,2,4-trichlorobenzene, re-
prohibitively long experiments if samples are run multiplicatively. It is
agent grade
acceptable to perform sample determinations using a single analysis.
Duplicate runs in accordance with 13.1 were performed for the round-
7.2 Deuterated o-dichlorobenzene or p-dichlorobenzene.
robin exercise.
This material is used at a concentration up to 20% with the
reagent specified in 7.1 as an internal lock.
11. Calculation
11.1 Measure the area between the appropriate integration
8. Hazards
limits outlined in Annex A1.
8.1 Warning—Solvents should be handled in a well-
11.2 Substitute the integrals into the appropriate equations
ventilated fume hood.
from Annex A2 to calculate the mole percent alkene-1.
9. Instrument Parameters
11.3 Annex A3 gives a sample calculation for an ethylene-
9.1 Pulse angle, 90° octene copolymer using integrals and equations in accordance
with 11.1 and 11.2.
9.2 Pulse repetition, 10 s
NOTE 9—With the prescribed repetition time (10 s) and pulse angle
9.3 Sample temperature, 130°C
(90°), the maximum allowable relaxation time (T ) for carbons used for
NOTE 4—The precise temperature should be measured using the NMR quantitative analysis is 2 s. To shorten the analysis time, a shorter pulse
thermometer (cyclooctane/methylene iodide).
repetition time can be used if one accounts for the relaxation time
differences. Relaxation times of carbons for the five copolymers were
9.4 Minimum signal-to-noise, 5000:1
determinedatacarbonfrequencyof50MHzusingtheinversionrecovery
8, 9
method. AppendixX1summarizestheserelaxationtimesandcorrection
NOTE 5—The signal-to-noise ratio is defined as 2.5 times the signal
factors(reciprocaloftherelativeintensities)fora4-srepetitiontime(T ).
intensity of the 30.0-ppm peak (isolated methylenes) divided by the peak R
With the shorter T , multiply integrals by these correction factors before
to peak noise for the region from 50 to 70 ppm. Calculation of R
using the equations in Annex A2. The T values would have to be
signal-to-noise is permitted using an equivalent software procedure.
remeasuredforanalysesperformedatspectrometerfrequenciesotherthan
9.5 Sweep width, 175 ppm
50 MHz.
9.6 Transmitter frequency (F1), 50 to 55 ppm
9.7 Apodisation, 2 (exponential) Hz
Randall, J. C., “NMR and Macromolecules,” Chapter 9, American Chemical
Society Symposium Series 247, 1984 .
Farrar,T.C.,andBecker,E.D., Pulse and Fourier Transform NMR,Chapter2,
Available from Wilmad Scientific Glass Co. Academic Press, New York, 1971.
6 9
Vidrime, D. W., and Peterson, P. E., Analytical Chemistry , Vol 48, 1976, p. Cheng, H. N., and Bennet, M. A., Macromolecule Chemistry , Vol 188, 1987,
1301. pp. 2665–2677.
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D5017 − 96 (2009)
11.4 If desired, convert results from mole percent alkene-1 prepared at one source, but the individual specimens were
tobranchesper1000carbons(br/1000C)usingtheequationsin prepared at the laboratories that tested them. Each “test result”
Annex A4. was the average of two individual determinations. Each labo-
ratory obtained one test result for each material. (Warning—
12. Report
The following explanations of r and R (13.2-13.2.3) are only
intended to present a meaningful way of considering the
12.1 Report the mole percent alkene-1 from 11.2 or
approximate precision of this test method. The data in Table 2
branches/1000C from 11.4, or both.
should not be rigorously applied to acceptance or rejection of
13. Precision and Bias
material, as those data are specific to the round robin and may
not be representative of other lots, conditions, materials, or
13.1 Table2isbasedonaroundrobinconductedin1988in
laboratories. Users of this test method should apply the
accordancewithPracticeE691,involvingninematerialstested
principlesoutlinedinPracticeE691togeneratedataspecificto
by six laboratories. For each material, all the samples were
theirlaboratoryandmaterials,orbetweenspecificlaboratories.
The principles of 13.2-13.2.3 would then be valid for such
Supporting data are available from ASTM Headquarters. Request RR:D20-
data.)
1192.
13.2 Concept of r and R—If S and S have been calc
...