The Characterization of Linear Polyethylene SRM 1475. II. Determination of Total Methyl Content by Infrared Spectrophotometry
Related Experiment Video
Updated: Oct 19, 2025

MALDI-ToF MS Method for the Characterization of Synthetic Polymers with Varying Dispersity and End Groups
Published on: October 3, 2025
1Institute for Materials Research, National Bureau of Standards, Washington, D.C. 20234.
Abstract:
An ASTM method was used to determine the methyl content of linear polyethylene SRM 1475 by measuring the absorbance at 1378 cm-1 (7.25 nm) of methyl groups on compensated infrared spectra. The methyl content of this polymer was found to be 0.15 methyls per 100 carbon atoms. Considering the methyls to be polymer end groups, the number average molecular weight computed approximates that determined by gel permeation chromatography within the experimental error. These values indicate that the polymer is essentially free of branching.
More Related Videos
Related Concept Videos
Polymer Classification: Stereospecificity
Polymer Classification: Architecture
Mass Spectrometry: Aromatic Compound Fragmentation
Mass Spectrometry: Long-Chain Alkane Fragmentation
Free-Radical Chain Reaction and Polymerization of Alkenes
¹³C NMR: Distortionless Enhancement by Polarization Transfer (DEPT)

