title: Separation of maleic anhydride grafted polypropylene using multidimensional high-temperature liquid chromatography.
abstract: Functionalization addresses a property gap of polyolefins and opens new perspectives due to improved surface properties in applications like composites (e.g., glass fiber reinforced polypropylene) and anti-corrosive coatings for metals. Various techniques have been developed to characterize functionalized polyolefins, yet no analytical approach addressing their chemical heterogeneity exists. Using High Temperature Size Exclusion Chromatography (HT-SEC) coupled to infrared spectroscopy we could show for two model samples of polypropylene grafted maleic anhydride (PP-g-MA), differing in their nominal MA content, that the grafting density increases with decreasing molar mass. Crystallization Analysis Fractionation (CRYSTAF) does not enable to separate these samples according to their composition to the extent required. Yet, when using High Temperature High Performance Liquid Chromatography (HT-HPLC), with either silica gel or Mica as stationary phase and a gradient mobile phase, a deformulation into a grafted and a non-grafted fraction could be achieved. This was confirmed by analyzing the eluted fractions by infrared spectroscopy. Hyphenating the separation according to composition with a separation according to molar mass (HT-HPLC x HT-SEC) enabled for the first time to reveal the bivariate distribution of PP-g-MA with regard to the molar mass and composition. Using on-line infrared detection quantitative information on the compositional and molar mass parameters of the individual fractions could be obtained.
authors.affiliation: Fraunhofer Institute for Structural Durability and System Reliability, Division Plastics, Group Material Analytics, Schlossgartenstrasse 6, 64289 Darmstadt, Germany.
authors.forename: K N
authors.initials: KN
authors.lastname: Prabhu
authors.affiliation: Fraunhofer Institute for Structural Durability and System Reliability, Division Plastics, Group Material Analytics, Schlossgartenstrasse 6, 64289 Darmstadt, Germany.
authors.forename: T
authors.initials: T
authors.lastname: Macko
authors.affiliation: Fraunhofer Institute for Structural Durability and System Reliability, Division Plastics, Group Material Analytics, Schlossgartenstrasse 6, 64289 Darmstadt, Germany. Electronic address: robert.bruell@lbf.fraunhofer.de.
authors.forename: R
authors.initials: R
authors.lastname: Brüll
authors.affiliation: SABIC Technology & Innovation, STC Geleen, P.O. Box 319, 6160 AH Geleen, The Netherlands.
authors.forename: K
authors.initials: K
authors.lastname: Remerie
authors.affiliation: SABIC Technology & Innovation, STC Geleen, P.O. Box 319, 6160 AH Geleen, The Netherlands.
authors.forename: J
authors.initials: J
authors.lastname: Tacx
authors.affiliation: SABIC Technology & Innovation, STC Geleen, P.O. Box 319, 6160 AH Geleen, The Netherlands.
authors.forename: P
authors.initials: P
authors.lastname: Garg
authors.affiliation: SABIC Technology & Innovation, STC Geleen, P.O. Box 319, 6160 AH Geleen, The Netherlands.
authors.forename: A
authors.initials: A
authors.lastname: Ginzburg
mesh_terms: D002850:Chromatography, Gel; D002851:Chromatography, High Pressure Liquid; D006358:Hot Temperature; D008299:Maleic Anhydrides / Q000737:chemistry; D008970:Molecular Weight; D011090:Polyenes / Q000737:chemistry*; D011126:Polypropylenes / Q000737:chemistry*
chemical_list: D008299:Maleic Anhydrides; D011090:Polyenes; D011126:Polypropylenes; C035051:PL 732
keywords: Functionalized polypropylene; HT 2D-LC; HT-HPLC; HT-SEC; IR-detection; liquid chromatography