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Lignin was used herein to prepare chemical grouting materials as replacements for petroleum-based epoxy precursors. Demethylation, phenolation, and hydroxymethylation were conducted and the products were characterized via FT-IR, 1H NMR, and GPC. A quantitative NMR method was used to study the precise changes in the functional group composition. Raw lignin (RL), demethylated lignin (DML), phenolated lignin (PHL), and hydroxymethylated lignin (HML) were respectively reacted with epichlorohydrin to synthesize various lignin epoxy resin (LEP), including raw lignin epoxy resin (RLEP), demethylated lignin epoxy resin (DMLEP), phenolated lignin epoxy resin (PHLEP), and hydroxymethylated lignin epoxy resin (HMLEP). With LEP as feedstocks, new grouting materials were prepared and the effects of the RLEP content and the LEP variants were investigated. The results demonstrated that the prepared lignin epoxy grouting resin had outstanding viscosity and mechanical properties with RLEP content up to 16%, and this performance greatly exceeded the industry standard. DMLEP, PHLEP, and HMLEP were able to provide better tensile properties, heat-resistance, chemical-resistance and curing performance compared with that achieved with RLEP. Overall, lignin has displayed great potential in replacing petroleum-based materials for the preparation of high-performance chemical grouting materials.

Samples of poly[1-(3-sulfopropyl)-2-vinyl-pyridinium-betaine] (PSPV) have been synthesized to high conversion by free radical polymerization in aqueous solution of the zwitterionic monomer SPV with several concentrations of the crosslinker N , N ′-methylene-bis-acrylamide (MBA). Hydrogels obtained by swelling them in water and aqueous KSCN solution were examined by gravimetric and dimensional analysis, and by compression–strain measurements. The derived effective crosslinking density ν e was only ca. 11% of the theoretical value, indicating low efficiency of chemical crosslinking by MBA. At 298 K increasing content of MBA produces increases in the values of ν e , elastic moduli and polymer–water interaction parameter χ . At a fixed MBA content, increasing temperature led to decreases in the values of ν e , elastic moduli and χ , but an increase in water content of hydrogel. For swelling in aq. KSCN solution the mechanical properties are insensitive to content of salt. Experimental and theoretical analysis afforded values of the water/polymer, salt/water and salt/polymer interaction parameters. Where appropriate the findings are compared with those reported for a different zwitterionic hydrogel and a neutral non-zwitterionic hydrogel.

Copolymeric hydrogels were prepared by the chemically initiated free radical copolymerization in aqueous solution of mixtures of [1-(3-sulfopropyl)-2-vinyl-pyridinium-betaine] (SPV) and (2-hydroxyethyl methacrylate) (HEMA) in the presence of a crosslinking agent N , N ′-methylene-bis-acrylamide (MBA). The hydrogels were swollen to equilibrium in water and aqueous KSCN at 298 K and their swelling behaviour has been investigated using gravimetric measurements. The effects of the concentration of KSCN and the mole fraction of SPV in the feed ( F s ) have been noted and discussed. The main findings are: (a) In water, the water content ( W 1 ) of copolymeric hydrogels is insensitive to SPV content at F s ⩾ 0.45. In contrast, W 1 decreases sharply with decreasing F s within the range of 0 F s W ) exceeds the value in pure water, the enhancement in swelling being most marked at low values of [KSCN]. The content of water within the hydrogel increases with KSCN concentration in the swelling medium for low values of [KSCN], but thereafter falls with further increase in salt concentration. In contrast, the salt content within the swollen hydrogel displays a continuous increase with increasing [KSCN]. All these results of item (b) are for copolymeric hydrogels within the full range of F s (0 F s W and W 1 increase sharply with increasing F s over the entire range of copolymer composition.

Samples of poly[1-(3-sulfopropyl)-2-vinyl-pyridinium-betaine] (PSPV) have been synthesized to high conversion by free radical polymerization in aqueous solution of the zwitterionic monomer SPV with several concentrations of the crosslinker N , N ′-methylene-bis-acrylamide (MBA). The densities of the resultant xerogels increased regularly with the content of MBA. Hydrogels obtained by swelling them in water and aqueous KSCN solution were examined by gravimetric and dimensional analysis. The water contents increased with decreasing content of MBA, the value of 92.7 wt% at the lowest MBA content being higher than that for other zwitterionic hydrogels. Enhanced swelling occurred in 1 M aq. KSCN at each MBA content, the total swelling being 98.1 wt% at the lowest crosslinker content. Swelling increased with increasing temperature. An approximate procedure to formulating swelling equilibrium in term of the volume fraction of water in hydrogel, in conjunction with the van’t Hoff equation, yields a small positive value for the enthalpy of swelling. This is compared with values derived similarly for other hydrogels.

The lightly sulfonated poly(phenylene oxide) (SPPO) ionomers in different ratio of DMSO (dimethyl sulfoxide)/trichloromethane mixing solvents were emulsified by adding water to form a series of waterborne microemulsions. The variations of conductivity, viscosity and surface tension of SPPO ionomer solution as well as the effect of the polarity of solvent systems on the phase inversion during the emulsification process were studied. The mechanism of phase inversion was proposed.