of 3V (Fig. 3.54a). For this fraction, there are two low molar mass components with
a slight difference in their molar masses which elute in SEC mode. It is assumed
that the first component (early eluting, approximately between 4.125 mL and
4.75 mL, SEC axis) comprises highly branched chains, which no longer show
adsorption on the stationary phase due to the interruption of the long continuous
methylene sequences by the branch points, or even random EP sequences in the
backbone chain. EPR components of 3VA-30 show a higher molar mass compared
to 3V-30, and no low molar mass iPP component is observed in this fraction (see
Fig. 3.54b).
EPCs of similar molar masses but different ethylene and propylene sequence
lengths as well as low and high molar mass iPP components were separated quite
well for the 60
C fraction of both samples (Fig. 3.54c, d). The 80
C and 90
C
fractions of sample 3V (Fig. 3.54e, g) contain both lower and slightly higher molar
mass iPP that eluted in pure 1-decanol and after the start of gradient, respectively.
The ethylene content of the EP copolymers determines their elution behaviour in
accordance with the elution behaviour of PE homopolymers on the Hypercarb
column. The same fractions for 3VA show only low molar mass iPP and high
molar mass EP copolymer (ethylene-rich). For 3VA-80, EP copolymer (ethylenerich) eluted at approximately 5.5 mL together with PE homopolymers having
similar molar masses.
To summarize, P-TREF fractionation and subsequent analysis of the individual
fractions by high-temperature solvent gradient interaction chromatography and
2D-LC was found to be an effective method for the comprehensive characterization
of complex polymeric materials such as IPCs. All components were identified by
coupling of the chromatographic separation to FTIR spectroscopy. FTIR provides
information not only on the ethylene and propylene contents but also on the
ethylene and propylene crystallinities.
References
1. Francuskiewicz F (1994) Polymer fractionation. Springer, Berlin
2. Mori S, Barth HG (1999) Size exclusion chromatography. Springer, Berlin
3. Striegel AM, Yau WW, Kirkland JJ, Bly DD (2009) Modern size-exclusion liquid chromatography. John Wiley, Hoboken, NJ
4. Pasch H, Trathnigg B (1998) HPLC of polymers. Springer, Berlin
5. Pasch H, Trathnigg B (2013) Multidimensional HPLC of polymers. Springer, Berlin
6. Pasch H, Malik I, Macko T (2013) Adv Polym Sci 251:77
7. Housaki T, Satoh K, Nishikida K, Morimoto M (1988) Makromol Chem Rapid Commun
9:525
8. Nishikida K, Housaki T, Morimoto M, Kinoshita T (1990) J Chromatogr A 517:209
9. www.chem.agilent.com/en-US/. . ./lc/gpc. . ./pl-gpc220
10. www.malvern.com/ViscotekHT-GPC
11. http://www.polymerchar.com/gpc-ir
12. Markovich RP, Hazlitt LG, Smith-Courtney L (1993) In: Provder T (ed) Chromatography of
polymers. Characterization by SEC and FFF, ACS symposium series 521. American Chemical Society, Washington, DC
142
3 Column-Based Chromatographic Techniques
a slight difference in their molar masses which elute in SEC mode. It is assumed
that the first component (early eluting, approximately between 4.125 mL and
4.75 mL, SEC axis) comprises highly branched chains, which no longer show
adsorption on the stationary phase due to the interruption of the long continuous
methylene sequences by the branch points, or even random EP sequences in the
backbone chain. EPR components of 3VA-30 show a higher molar mass compared
to 3V-30, and no low molar mass iPP component is observed in this fraction (see
Fig. 3.54b).
EPCs of similar molar masses but different ethylene and propylene sequence
lengths as well as low and high molar mass iPP components were separated quite
well for the 60
C fraction of both samples (Fig. 3.54c, d). The 80
C and 90
C
fractions of sample 3V (Fig. 3.54e, g) contain both lower and slightly higher molar
mass iPP that eluted in pure 1-decanol and after the start of gradient, respectively.
The ethylene content of the EP copolymers determines their elution behaviour in
accordance with the elution behaviour of PE homopolymers on the Hypercarb
column. The same fractions for 3VA show only low molar mass iPP and high
molar mass EP copolymer (ethylene-rich). For 3VA-80, EP copolymer (ethylenerich) eluted at approximately 5.5 mL together with PE homopolymers having
similar molar masses.
To summarize, P-TREF fractionation and subsequent analysis of the individual
fractions by high-temperature solvent gradient interaction chromatography and
2D-LC was found to be an effective method for the comprehensive characterization
of complex polymeric materials such as IPCs. All components were identified by
coupling of the chromatographic separation to FTIR spectroscopy. FTIR provides
information not only on the ethylene and propylene contents but also on the
ethylene and propylene crystallinities.
References
1. Francuskiewicz F (1994) Polymer fractionation. Springer, Berlin
2. Mori S, Barth HG (1999) Size exclusion chromatography. Springer, Berlin
3. Striegel AM, Yau WW, Kirkland JJ, Bly DD (2009) Modern size-exclusion liquid chromatography. John Wiley, Hoboken, NJ
4. Pasch H, Trathnigg B (1998) HPLC of polymers. Springer, Berlin
5. Pasch H, Trathnigg B (2013) Multidimensional HPLC of polymers. Springer, Berlin
6. Pasch H, Malik I, Macko T (2013) Adv Polym Sci 251:77
7. Housaki T, Satoh K, Nishikida K, Morimoto M (1988) Makromol Chem Rapid Commun
9:525
8. Nishikida K, Housaki T, Morimoto M, Kinoshita T (1990) J Chromatogr A 517:209
9. www.chem.agilent.com/en-US/. . ./lc/gpc. . ./pl-gpc220
10. www.malvern.com/ViscotekHT-GPC
11. http://www.polymerchar.com/gpc-ir
12. Markovich RP, Hazlitt LG, Smith-Courtney L (1993) In: Provder T (ed) Chromatography of
polymers. Characterization by SEC and FFF, ACS symposium series 521. American Chemical Society, Washington, DC
142
3 Column-Based Chromatographic Techniques