Sulfonation of low-density polyethylene and its impact on polymer properties

Abstract

Sulfonation of polymers is of great importance for the packaging industry mainly due to its effect on the alteration of surface functionality of polymer films. In this study we customized liquid phase sulfonation of low‐density polyethylene (LDPE) swelling the polymer by using a combination of polar and nonpolar solvents. Swollen polymer was treated with sulfuric acid of varying concentrations with continuous mixing for in‐depth sulfonation of the polymer. Presence of cyclohexane and ethanol, as polar and nonpolar reagents, not only kept the batch under isothermal conditions but also homogenously influenced in‐depth functionalization of LDPE. The durability of the sulfonated polymer was determined by grinding the test samples 30 days after the reaction. Fourier transform‐infrared spectroscopy indicated presence of functional group moieties, which is also supported by increase of 5% and 1.35% in density and sulfur contents of the polymer, respectively. Contact angle measurements indicate 30° decrease in values of the sulfonated polymer which corresponds with decrease in carbon to hydrogen ratio (from 5.9 to 5.3) and increase in sulfur to carbon ratio (up to 0.0184) resulting from the sulfonation of the polymer. Differential scanning calorimetery results indicate almost linear reduction in the crystallinity of LDPE with an increase in acid concentration used for the sulfonation reaction. POLYM. ENG. SCI., 54:2522–2530, 2014. © 2013 Society of Plastics Engineers

Environmentally Friendly Route for Fabricating Conductive Agent for Lithium-Ion Batteries: Carbon Nanoparticles Derived from Polyethylene

“…Further, ketone peak around 1700 cm −1 and O-H single bond peak started to appear with the simultaneous disappearance of C-H bonds. Changes in O-H and C=O bonds are related to attachment of oxygen functional group and sulfone functional group during the sulfonation process [8,10,21,22]. Lastly, Raman spectroscopy was used to conclude chemical structural change of PE chains into a cyclic structure (Figure 3).…”

Analysis of partially sulfonated low density polyethylene (LDPE) membranes as separators in microbial fuel cells

“…where DH f is the change in the enthalpy of fusion of the polyethylene lm, and DH * f is the standard value for the enthalpy of fusion of the polyethylene lm (293.1 J g À1 ). 24 The membrane crystallinity nature was found to be inversely related with the sulfonation duration, although increments in the % crystallinity of the SPE-45 and SPE-60 membranes were observed due to the formed crosslinks (Table T1, ESI †). The results indicated the effects of sulfonation and crosslinking on the membrane crystallinity properties and melting temperatures.…”

“…[17][18][19][20][21] Various studies on the surface sulfonation of polyethylene lms have been performed using oleum and chlorosulfonic acid in an organic phase solvent. [22][23][24][25] In a study, Whitesides et al have shown carboxylic group incorporations on the surfaces of low density polyethylene lms through ATR IR spectroscopy. 26 Idage et al have also shown the incorporation of functional groups during the surface sulfonation of HDPE lms using X-ray photoelectron spectroscopy.…”

Study On Polyethylene-Based Carbon Fibers Obtained by Sulfonation Under Hydrostatic Pressure

“…Several studies have examined polyethylene-based carbon bers and various attempts to improve the tensile strength of polyethylene-based carbon bers have been made [19][20][21][22][23][24][25][26][27][28]. J. Kim and J. Lee examined polyethylene-derived carbon bers using LLDPE.…”