CASE STUDY. Degradation of Polyethylene by FTIR and High Temperature GPC

Transcription

1 Degradation of Polyethylene by FTIR and High Temperature GPC CASE STUDY Degradation of Polyethylene by FTIR and High Temperature GPC PROBLEM The objective of this analysis was to determine if thermal degradation had occurred in a polyethylene sample by Fourier Transform Infrared Analysis (FTIR) and High Temperature Tetradetection Gel Permeation Chromatography (GPC-HT). ANALYTICAL STRATEGY FTIR is will be used to identify the portion of brown discoloration of the polyethylene sample, while high temperature GPC will be performed to compare the molecular weights of the sample and a virgin polyethylene. CONCLUSIONS The FTIR spectrum of the sample was found to be consistent with oxidized polyethylene. The failed PE sample was found to show an increase in molecular weight as compared to the virgin material. Read the following report to see the full analysis. Page 1

2 Page 1 of 33 Final Report Jordi Labs LLC Degradation of Polyethylene by FTIR and High Temperature GPC Case Study Date: XX/XX/XX Released by: Dr. Mark Jordi President Jordi Labs LLC Report Number: JXXXX Jordi Labs LLC - Confidential

3 Page 2 of 33 Date Client Name Company Name Address Dear Valued Client, Please find enclosed the test results for your sampled described as: 1. Virgin PE sheet 2. Failed PE Sheet (Lot# ASABFY) The following tests were performed: 1. Fourier Transform Infrared Spectroscopy (FTIR) 2. High Temperature Tetradetection Gel Permeation Chromatography (GPC-HT) Objective The objective of this analysis was to determine if thermal degradation had occurred in a polyethylene sample by Fourier Transform Infrared Analysis (FTIR) and High Temperature Tetradetection Gel Permeation Chromatography (GPC-HT). Summary of Results Visual observation of the sample shows a brown discoloration in the failed PE sheet as shown in Image 1. The FTIR spectrum of the sample was compared to our database of ~23,000 entries and found to be consistent with oxidized polyethylene. The peak at 1722 cm -1 is diagnostic for C=O which is consistent with oxidation of the polymer. Table II shows the molecular weight values as determined by GPC-HT. The failed PE sample was found to show an increase in molecular weight as compared to the virgin material. This is at first counter intuitive but is often observed in polyolefin degradation due to the onset of crosslinking.

4 Page 3 of 33 Individual Test Results A summary of the individual test results is provided below. All accompanying data, including spectra, has been included in the data section of this report. FTIR Image 1. Sample Lot# ASABFY A thin portion of the sample was extracted using a clean, sharp razor blade and analyzed by FT-IR. The spectrum was compared to our library database of ~23,000 entries and found to be consistent with oxidized polyethylene. The presence of additional peaks at 1722 and 1182 cm -1 suggests oxidation. These bands are consistent with C=O and ether functional groups. Table 1 shows the peak identifications for the failed sample and the virgin polyethylene. Figure 1 shows the FT-IR spectrum for the failed sample and Figure 2 shows the spectrum of the virgin polyethylene sample.

5 Page 4 of 33 Figure 1. FT-IR Spectrum for Lot# ASABFY IR Frequency (cm -1 ) Table 1 FTIR Peaks and Identifications Functional Group Lot# ASABFY Polyethylene Reference C-H asymmetric Stretch in CH C-H symmetric Stretch in CH C=O stretch CH 2 bend 1376 CH 3 bend 1182 C-O-C stretch CH 2 rock 2

6 Page 5 of 33 Figure 2. FT-IR Spectrum for Virgin Polyethylene Figure 3. FT-IR Spectrum Overlay of Failed (Blue) and Virgin Polyethylene (Red)

7 Page 6 of 33 Figure 4. FT-IR Spectrum Overlay of Failed Polyethylene (black) and Oxidized Polyethylene (light blue) Best Match GPC-HT Table II shows the results for a series of standards analyzed to demonstrate system performance. Polystyrene standards were analyzed with weight average molecular weights of 233,643 and 99,420. Confirmation of the accuracy of our calibration was achieved by running a linear polyethylene standard that was obtained from the National Institute of Standards and Technology (1475a). Table III shows the results for the samples. The method of known dn/dc was applied for the samples as the chemistry was known. Overlays are provided for the polyethylene samples in Figures 5-8. The failed PE sample was found to show a higher molecular weight as compared to the virgin resin. A significant increase in the light scattering signal was observed as shown in Figure 6. This indicates the presence of crosslinking in the degraded sample. Table II. Standards Standard Analysis (GPC-T) (PS 99,420) Sample Mn Mw Mz Mw/Mn IV Rh ;56;18 PS99K 99420Da 02.vdt 99,329 99, , ID dn/dc Conc PS99K 99420Da

8 Page 7 of 33 Standard Analysis (GPC-T) (PS 233,643) Sample Mn Mw Mz Mw/Mn IV Rh ;58;09 PS235K Da 01.vdt 108, , , ;01;55 PS235K Da 03.vdt 108, , , ID dn/dc Conc PS235K Da PS235K Da NIST 1475a Linear Polyethylene Analysis (Mw = 53,070) Sample Mn Mw Mz Mw/Mn IV Rh ;37; A 02.vdt 19,290 53, , ;39; A 03.vdt 19,291 53, , ID dn/dc Conc 1475A A Table III. Analysis of Samples Virgin PE Sheet (GPC-T) Sample Mn Mw Mz Mw/Mn IV Rh _04;47;59_modified_P Virgin PE 44, , , Virgin PE 06;51;32 modified P 44, , , ID dn/dc Conc Virgin modified PE Virgin modified PE Failed PE Sheet (GPC-T) Sample Mn Mw Mz Mw/Mn IV Rh Failed PE 02;44;29 degraded PE 44, , e Failed PE 03;46;14 degraded PE 43, , e ID dn/dc Conc Failed PE Failed PE

9 Page 8 of Failed PE = Red Virgin PE = Green Refractive Index (mv) Retention Volume (ml) _02;44;29 degraded_pe_sheets_02.vdt: Refractive Index _04;47;59_modified_PE_sheet_01.vdt: Refractive Index Figure 5: Overlay of refractive index curves for the virgin PE (green) and Failed PE (red) samples Failed PE = Red Virgin PE = Green Right Angle Light Scattering (mv) Retention Volume (ml) _02;44;29 degraded_pe_sheets_02.vdt: Right Angle Light Scattering _04;47;59_modified_PE_sheet_01.vdt: Right Angle Light Scattering Figure 6: Overlay of Right Angle Light Scattering curves for the virgin PE (green) and Failed PE (red) samples.

10 Page 9 of Failed PE = Red Virgin PE = Green Viscometer - DP (mv) Retention Volume (ml) _02;44;29 degraded_pe_sheets_02.vdt: Viscometer - DP _04;47;59_modified_PE_sheet_01.vdt: Viscometer - DP Figure 7: Overlay of Viscometry curves for the virgin PE (green) and Failed PE (red) samples Log Molecular Weight Normalized Wt Fr Retention Volume (ml) _02;44;29 degraded_pe_sheets_02.vdt: Log Molecular Weight Normalized Wt Fr _04;47;59_modified_PE_sheet_01.vdt: Log Molecular Weight Normalized Wt Fr Figure 8: Overlay of weight fraction and log molecular weight curves for the virgin PE (green) and Failed PE (red) samples.

11 Page 10 of 33 Analysis Conditions Information on the specific conditions used to perform the analysis is typically listed in this section of the report. Closing Comments Deformulation of an unknown material is intended to provide a best estimate of the chemical nature of the sample. All chemical structures are supported by the evidence presented but are subject to revision upon receipt of additional evidence. Additional factors such as material processing conditions may also affect final material properties. Jordi Labs reports are issued solely for the use of the clients to whom they are addressed. No quotations from reports or use of the Jordi name is permitted except as authorized in writing. The liability of Jordi Labs with respect to the services rendered shall be limited to the amount of consideration paid for such services and do not include any consequential damages. Jordi Labs specializes in polymer testing and has 30 years experience doing complete polymer deformulations. We are one of the few labs in the country specialized in this type of testing. We will work closely with you to help explain your test results and solve your problem. We appreciate your business and are looking forward to speaking with you concerning these results. Sincerely, Kiran Rana Mark Jordi Kiran Rana, M.S. Mark Jordi, Ph. D. Chemist President Jordi Labs LLC Jordi Labs LLC Laurie Scharp Laurie Scharp Chemist Jordi Labs LLC

12 Page 11 of 33 Appendix Table of Contents Page System Calibration using PS 99,420 (PS99K) Page PS 235K Standard Analysis (233,643) Page NIST 1475a Linear Polyethylene Standard Page Samples Page FTIR Data

13 Page 12 of 33 System Calibration using PS 99,420 (PS99K)

14 Page 13 of 33 System Calibration using PS 99,420 (PS99K) Refractive Index (mv) Low Angle Light Scattering (mv) Viscometer - DP (mv) Right Angle Light Scattering (mv) Retention Volume (ml) _10;56;18_PS99K_99420Da_02.vdt: Refractive Index Right Angle Light Scattering Low Angle Light Scattering Viscometer - DP PS 99K: RI, RALS, LALS DP Overlay Chromatogram Cumulative Weight Fraction Log Molecular Weight _10;56;18_PS99K_99420Da_02.vdt: Cumulative Weight Fraction PS99K: Cumulative Weight Fraction Curve

15 Page 14 of Log Molecular Weight Normalized Wt Fr Retention Volume (ml) _10;56;18_PS99K_99420Da_02.vdt: Log Molecular Weight Normalized Wt Fr PS99K: MW Distribution Curve

16 Page 15 of 33 PS 235K Standard Analysis (233,643)

17 Page 16 of 33 PS 235K Standard Analysis (233,643) Refractive Index (mv) Low Angle Light Scattering (mv) Viscometer - DP (mv) Right Angle Light Scattering (mv) Retention Volume (ml) _11;58;09_PS235K_233643Da_01.vdt: Refractive Index Right Angle Light Scattering Low Angle Light Scattering Viscometer - DP PS 235K: RI, RALS, LALS DP Overlay Chromatogram Cumulative Weight Fraction Log Molecular Weight _11;58;09_PS235K_233643Da_01.vdt: Cumulative Weight Fraction PS 235K: Cumulative Weight Fraction Curve

18 Page 17 of Log Molecular Weight Normalized Wt Fr Retention Volume (ml) _11;58;09_PS235K_233643Da_01.vdt: Log Molecular Weight Normalized Wt Fr PS 235K: MW Distribution Curve Log Intrinsic Viscosity Log Molecular Weight _11;58;09_PS235K_233643Da_01.vdt: Log Intrinsic Viscosity PS 235K: Mark Houwink Plot

19 Page 18 of 33 NIST 1475a Linear Polyethylene

20 Page 19 of 33 NIST 1475a Linear Polyethylene Refractive Index (mv) Low Angle Light Scattering (mv) Viscometer - DP (mv) Right Angle Light Scattering (mv) Retention Volume (ml) _19;37;55_1475A_02.vdt: Refractive Index Right Angle Light Scattering Low Angle Light Scattering Viscometer - DP NIST 1475a Linear Polyethylene: RI, RALS, LALS DP Overlay Chromatogram Cumulative Weight Fraction Log Molecular Weight _19;37;55_1475A_02.vdt: Cumulative Weight Fraction NIST 1475a Linear Polyethylene: Cumulative Weight Fraction Curve

21 Page 20 of Log Molecular Weight Normalized Wt Fr Retention Volume (ml) _19;37;55_1475A_02.vdt: Log Molecular Weight Normalized Wt Fr NIST 1475a Linear Polyethylene: MW Distribution Curve Log Intrinsic Viscosity Log Molecular Weight _19;37;55_1475A_02.vdt: Log Intrinsic Viscosity NIST 1 475a Linear Polyethylene: Mark Houwink Plot

22 Samples Page 21 of 33

23 Page 22 of 33 Modified PE sheet Refractive Index (mv) Low Angle Light Scattering (mv) Viscometer - DP (mv) Right Angle Light Scattering (mv) Retention Volume (ml) _13;09;33_degraded_modified_PE_sheet_01.vdt: Refractive Index Right Angle Light Scattering Low Angle Light Scattering Viscometer - DP Modified PE sheet: RI, RALS, LALS DP Overlay Chromatogram Cumulative Weight Fraction Log Molecular Weight _13;09;33_degraded_modified_PE_sheet_01.vdt: Cumulative Weight Fraction Modified PE sheet: Cumulative Weight Fraction Curve

24 Page 23 of Log Molecular Weight Normalized Wt Fr Retention Volume (ml) _13;09;33_degraded_modified_PE_sheet_01.vdt: Log Molecular Weight Normalized Wt Fr Modified PE sheet: MW Distribution Curve Log Intrinsic Viscosity Log Molecular Weight _13;09;33_degraded_modified_PE_sheet_01.vdt: Log Intrinsic Viscosity Modified PE sheet: Mark Houwink Plot

25 Page 24 of 33 Degraded PE Sheet Refractive Index (mv) Low Angle Light Scattering (mv) Viscometer - DP (mv) Right Angle Light Scattering (mv) Retention Volume (ml) _10;03;57_modified_PE_Sheet_01.vdt: Refractive Index Right Angle Light Scattering Low Angle Light Scattering Degraded PE Sheet-01.vdt. Viscometer - DP Degraded PE Sheet: RI, RALS, LALS DP Overlay Chromatogram Cumulative Weight Fraction Log Molecular Weight _10;03;57_modified_PE_Sheet_01.vdt: Degraded Sheet-01.vdt. Cumulative Weight Fraction Degraded PE Sheet: Cumulative Weight Fraction Curve

26 Page 25 of Log Molecular Weight Normalized Wt Fr Retention Volume (ml) _10;03;57_modified_PE_Sheet_01.vdt: Degraded Sheet-01.vdt. Log Molecular Weight Normalized Wt Fr Degraded PE Sheet: MW Distribution Curve Log Intrinsic Viscosity Log Molecular Weight _10;03;57_modified_PE_Sheet_01.vdt: Degraded Sheet-01.vdt. Log Intrinsic Viscosity Degraded PE Sheet: MW Distribution Curve

27 FTIR Data Page 26 of 33

28 Copr. 1980, Sadtler. All Rights Reserved. Page 27 of Lot# ASABFY

29 Copr. 1980, Sadtler. All Rights Reserved. Page 28 of Lot# ASABFY (in black) Oxidized Polyethylene (in green)

30 Copr. 1980, Sadtler. All Rights Reserved. Page 29 of OM #1; A-C POLYETHYLENE Name(s): A-C POLYETHYLENE 316 Source Of Sample: ALLIED FIBERS AND PLASTICS COMPANY, ALLIED CORPORATION Technique: FILM (CAST FROM o-dichlorobenzene) Density: 0.98 Classification: Polymers: POLYETHYLENES Solution Data: Acid Number: 16 Viscosity Data: (Brookfield): (140C) CPS Softening Point: 140C Comments: Chemical Description: OXIDIZED ETHYLENE HOMOPOLYMER

31 Page 30 of 33 Index HQI Chemical Name Spectrum OM # PETROLITE C-4040 OM # DISLON OM # PETROTHENE NL OM # CERAMER 5005 OL # BAYLON V22H764*LOW DENSITY POLYETHYLENE OM # POLY-ETH 2255 RC # ROCK F T WAX OM # A-C POLYETHYLENE 316 OM # POLY-ETH 2205 QF # HEPTACOSANE OL # M-P-A 60-T (TOLUENE) OM # HOSTALEN GK9050 HO AS # DAF 618 FILM FORMULATED WITH AN ADHESI... OM # ESCOR ATX 310 OL # PARVAN 3150, F.N. 3502*REFINED PARAFFI... SR # PARVAN 3150, F.N. 3502*REFINED PARAFFI... SR # PARVAN 3150, F.N. 3502*REFINED PARAFFI... SR # PARVAN 3150, F.N. 3502*REFINED PARAFFI... PL # WAX X-12 : MIXTURE OF STRAIGHT CHAIN F... AS # AREMCO #562 OM # PETROTHENE HD 5002 AS # THERMOGRIP 1317

32 Page 31 of 33 Index HQI Chemical Name Spectrum OL # POLY EM 40*PH STABLE ANIONIC POLYETHYL... OM # VOLARA 2E OL # PARVAN 4550, F.N. 3519*REFINED PARAFFI...

33 Page 32 of Polyethylene

34 Page 33 of Lot# ASABFY (in black) Polyethylene Reference (in red)