Nylon‐6 film grafted with acrylic acid for dissepiment in alkaline storage batteries

Abstract

A grafted nylon‐6 membrane that can be used in alkaline storage batteries was prepared by grafting acrylic acid onto nylon‐6 film using (NH4)2Ce(NO3)6/H2SO4 as initiator. The nylon‐6 films to be grafted were pre‐swelled in 20% formic acid solution, activated with an aqueous solution containing ceric ammonium nitrate and sulfuric acid. The grafting efficiency was greatly affected by the reaction temperature, the concentration of (NH4)2Ce(NO3)6/H2SO4, and the swelling time in formic acid. The degree of grafting that could be achieved under optimized conditions was up to 312%. Through infrared spectroscopy (IR) and X‐ray photoelectron spectroscopy (XPS) analysis, it was realized that graft reaction took place on the nitrogen atom of the amide group and the density of grafting point increased with an increase in the degree of grafting in a certain range. The highest density of grafting point was found to be 51.3% in a given set of reaction conditions. X‐ray diffraction illustrated that the crystallinity of the grafted membranes decreases with the increase of the degree of grafting. A membrane with 173% degree of grafting showed electric resistance of 0.11 Ω/cm2, and ion exchange capacity (IEC) of 8.7 mmol/g, which can meet the requirement for the electric discharge of storage batteries with strong power. Copyright © 2004 John Wiley & Sons, Ltd.

Structuring and characterization of a novel highly microporous PEI/BMI semi-interpenetrating polymer network

“…The H-bonded or positively charged amines have a binding energy at 401.7 eV [55]. An increase in the binding energy from 399.7 to 401.6 eV was observed when amide nitrogen in Nylon-6 was grafted with polyacrylic acid [44]. The presence of electron-withdrawing group such as carbonyl moiety and neighboring amine group lead to an increase in the positive Fig.…”

“…8. The binding energy in the range of 399.3-400.2 eV was assigned to amide group as reported elsewhere [44,49,55]. The increase in the intensity within this range for PEI-BMI-EtOH (S and L) membranes might be attributed to amide groups resulted from imide cleavage.…”

“…The peak at 1446 cm K1 labeled (i) was assigned to the scissoring CH 2 symmetric bending [43] as well as to CH 3 asymmetric bending [40]. The increase in the intensity of the peak (i) with the appearance of a shoulder at 1454 cm K1 might be attributed to amide N-H bending [42] and OH bending [44] involved in hydrogen bonding (Table 4). Therefore, we might suggest the presence of amide in amic acid group in the structure of PEI-BMI-EtOH S and L membranes.…”

Nickel–metal hydride battery separators fabricated from sulfonated nonwovens

“…Currently, there are generally two methods to improve the hydrophilicity of separators. One is surface treatment with wet chemicals, corona discharge, plasma, 4 and so on, and another is the introduction of hydrophilic groups, such as carboxylic 5,6 and sulfonic groups, 7,8 onto the polymer through graft reactions. In this study, we improved the wettability of polyolefin nonwovens through sulfonation reactions and fabricated them into Ni-MH batteries as separators.…”