Premium
Structure—performance relationships of viscosity index improvers: I microstructural determination of olefin copolymers by NMR spectroscopy
Author(s) -
Kapur G. S.,
Sarpal A. S.,
Mazumdar S. K.,
Jain S. K.,
Srivastava S. P.,
Bhatnagar A. K.
Publication year - 1995
Publication title -
lubrication science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.632
H-Index - 36
eISSN - 1557-6833
pISSN - 0954-0075
DOI - 10.1002/ls.3010080106
Subject(s) - comonomer , copolymer , nuclear magnetic resonance spectroscopy , materials science , spectroscopy , viscosity index , carbon 13 nmr , dept , analytical chemistry (journal) , viscosity , proton nmr , chemistry , polymer chemistry , chromatography , organic chemistry , composite material , stereochemistry , polymer , scanning electron microscope , physics , base oil , quantum mechanics
Five commercial olefin copolymer (OCP) viscosity index (VI) improvers have been characterised at the molecular level. The copolymer compositions have been determined using 1 H and 13 C‐NMR spectroscopy. The microstructural parameters, such as comonomer sequence distribution, number average sequence lengths and run number, have been determined by 13 C‐NMR spectroscopy. NMR spectral editing techniques, e.g. Distortionless Enhancement via Polarisation Transfer (DEPT) have been used for peak assignments. This analytical approach aims at correlating the microstructural parameters with the physical properties and performance of these VI improvers, to be communicated later.