Sulfonation of (glycidyl methacrylate) chains grafted onto nonwoven polypropylene fabric

A two-step process has been invented to prepare sulfonated polypropylene from chlorinated polypropylene via thiolation and successive oxidation to enhance the dyeability of polypropylene. With a short thiolation reaction time of 3 h in an N-methyl-2-pyrrolidone solution, 1.7-20.5% sulfur can be incorporated into a polypropylene bulk effectively. Chlorine-thiol substitution and hydrosulfide conversion have been examined with elemental analysis, and their behaviors as a function of the SH/Cl ratio can be explained with an equilibrium model of hydrosulfide and accessible chlorine in a given timescale. Oxidation of thiol has been performed successfully with hydrogen peroxide. The evolution of oxidation intermediates such as sulfoxide, sulfone, sulfinic acid, and sulfonic acid can be identified by Raman and Fourier transform infrared analyses. Sulfonated polypropylene can be stained by a basic dye very effectively, and its dye uptake reaches 190 mmol of dye/kg of polymer for 3.6 mmol of sulfur/g of polymer. This dye uptake is 20 times more effective than that of chlorinated polypropylene on a molar basis. Thus, it is clear that a modification can be performed effectively to enhance the dyeability of polypropylene.

Section: Introductionmentioning

confidence: 99%

Preparation of sulfonated polypropylene and its dyeability: Thiol as a functionalization template of polypropylene

Choi

Park

2008

“…Styrene (St) is often grafted onto polymer fiber and film surfaces since the following‐up functionalization can be realized on the benzene ring, however, sulfonation was implemented in caustic conditions. The sulfonation of polyethylene‐g‐glycidyl methacrylate (GMA) membrane even lasted for a few days . PP‐g‐St particles were sulfonated by being immersed in 98% H 2 SO 4 in a weight‐to‐volume ratio of 1/5 at 98 °C for 2 h, while the poly(vinylidene fluoride)‐g‐ St membranes were functioned by being soaked in 98% H 2 SO 4 at 70 °C for 8 h .…”

Section: Introductionmentioning

confidence: 99%

Microstructure and sulfonation of dual monomer‐grafted polypropylene nonwoven fabrics

Tao

Pang

et al. 2019

The sulfonation of styrenic polymers often needs harsh reaction conditions, such as concentrated sulfuric acid and elevated temperature. The awkward situation is handled by grafting copolymerization of polar and nonpolar monomers, and essentially the surface wettability between sulfonating agent and matrix polymer is circumvented in the study. Two pairs of dual monomers, glycidyl methacrylate (GMA)-acrylic acid (AA), styrene (St)-acrylic acid (AA), were grafted onto polypropylene nonwoven fabrics (PP) using thermal polymerization, and the resulted fabrics were further sulfonated using sodium sulfite and sulfuric acid, respectively. The microstructure of the modified fabrics was characterized by infrared spectroscopy and scanning electron microscopy. The ion exchange property was verified by copper (II) removal from aqueous solution, and its reutilization was carried out in electrochemical desorption process. The results show that hydrophilic and active monomer AA speeds grafting and sulfonation, but overload of AA will deteriorate copolymerization of GMA, and switch copolymerization chain component due to acylation with benzene ring. Although interfacial compatilizer promotes dual grafting, its overdosing may intensify microphase segregation of the grafting polymers owing to emulsification. The resultant granular polymers will be drained off during functionalization and reutilization processes. The ion exchange fabrics can be applied for treatment of metal ion wastewaters with unique electrochemical desorption feature.

“…There have been strong demands for highly crosslinked polymer particles [1][2][3][4][5][6][7][8][9] with superior heat resistance, solvent resistance, and mechanical strength because of their extensive applications such as column packing materials, 6 protein synthesis and biomedical applications, 7 polymer-supported catalysis, spacer for display uses, conductive ball, etc. Therefore, the development of a novel technique for the preparation of monodispersed highly crosslinked polymer particles becomes an important research subject.…”

Section: Introductionmentioning

confidence: 99%

Highly crosslinked micron‐sized, monodispersed polystyrene particles by semicontinuous dispersion polymerization. II. Semicontinuous, delayed addition and seeded semicontinuous processes

Lee

2009

A highly crosslinked, monodispersed polystyrene (PS) particle was prepared by the seeded semicontinuous dispersion polymerization using ready-made monodispersed PS seed particles. The effects of Styrene (in 2nd stage)/Styrene (in PS seed) ratio, addition point and feeding time of divinylbenzene (DVB), concentration of DVB and polymerization temperature on the particle size, size distribution and morphology of the resulting particles were investigated. Monodispersed PS particles with 15 wt % of the DVB were prepared at 1/1 in St/St ratio, In comparison, highly crosslinked monodispersed and smooth-surfaced PS particles containing up to 70 wt % of the DVB were effectively prepared at 0/1. 5% weight loss of the PS particles determined by TGA occurred from 353.3 to 389.6 C and the degree of swellability in toluene decreased from 113 to 101% as the DVB concentration increased from 10 to 70 wt %, implying increased thermal stability and solvent resistance due to the increase of the crosslink density. This study demonstrates that the seeded semicontinuous process, primarily with the starved condition at the second stage, is an efficient way to obtain highly crosslinked, monodispersed PS particles.