Adv Polym Sci (2013) 257: 203–252
DOI: 10.1007/12_2013_216
© Springer-Verlag Berlin Heidelberg 2013
Published online: 16 May 2013
Polyolefin Characterization: Recent
Advances in Separation Techniques
Benjamı ´n Monrabal
Abstract New polyolefin resins, in spite of their simple chemistry, just carbon
and hydrogen atoms, have become by design complex polymers with improved
performance for the desired application. Besides the fundamental molar mass
distribution, there are many other features that can be controlled when dealing
with copolymers and new multireactor/multicatalyst resins. The average properties
measured by spectroscopic techniques are not enough to define the microstructure
of the new resins; it is necessary to fractionate the polymer according to certain
parameters such as molar mass, branching, or stereoregularity. Separation techniques
have become essential for the control and characterization of these polymers;
nevertheless, full characterization is not a simple task and has demanded the
development of new separation methodologies in recent years, and in many cases
multiple separation techniques are required to define the microstructure. A review
of the most important separation techniques with emphasis on the new technologies
is given and the applications of these new polyolefin resins discussed.
Keywords Cross-fractionation chromatography Á Crystallization analysis
fractionation Á Crystallization elution fractionation Á Field flow fractionation Á Gel
permeation chromatography Á High temperature liquid chromatography Á
Size-exclusion chromatography Á Solvent gradient interaction chromatography Á
Temperature rising elution fractionation Á Thermal gradient interaction chromatography
Contents
1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 205
2 Polyolefin Microstructure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 206
2.1 Polyethylene Microstructure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 207
2.2 Polypropylene Microstructure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 209
B. Monrabal (*)
Polymer Char, Valencia, Spain
e-mail: benjamin.monrabal@polymerchar.com
DOI: 10.1007/12_2013_216
© Springer-Verlag Berlin Heidelberg 2013
Published online: 16 May 2013
Polyolefin Characterization: Recent
Advances in Separation Techniques
Benjamı ´n Monrabal
Abstract New polyolefin resins, in spite of their simple chemistry, just carbon
and hydrogen atoms, have become by design complex polymers with improved
performance for the desired application. Besides the fundamental molar mass
distribution, there are many other features that can be controlled when dealing
with copolymers and new multireactor/multicatalyst resins. The average properties
measured by spectroscopic techniques are not enough to define the microstructure
of the new resins; it is necessary to fractionate the polymer according to certain
parameters such as molar mass, branching, or stereoregularity. Separation techniques
have become essential for the control and characterization of these polymers;
nevertheless, full characterization is not a simple task and has demanded the
development of new separation methodologies in recent years, and in many cases
multiple separation techniques are required to define the microstructure. A review
of the most important separation techniques with emphasis on the new technologies
is given and the applications of these new polyolefin resins discussed.
Keywords Cross-fractionation chromatography Á Crystallization analysis
fractionation Á Crystallization elution fractionation Á Field flow fractionation Á Gel
permeation chromatography Á High temperature liquid chromatography Á
Size-exclusion chromatography Á Solvent gradient interaction chromatography Á
Temperature rising elution fractionation Á Thermal gradient interaction chromatography
Contents
1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 205
2 Polyolefin Microstructure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 206
2.1 Polyethylene Microstructure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 207
2.2 Polypropylene Microstructure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 209
B. Monrabal (*)
Polymer Char, Valencia, Spain
e-mail: benjamin.monrabal@polymerchar.com