PolyHIPE/pullulan composites derived from glycidyl methacrylate and 1,3‐butanediol dimethacrylate‐based high internal phase emulsions

Abstract

Highly porous composites of poly(glycidyl methacrylateco-1,3-butanediol dimethacrylate) and pullulan were prepared as semi-interpenetrating polymer networks by cross-linking of high internal phase emulsions (HIPEs). HIPEs were prepared by using an aqueous phase made of pullulan dissolved in deionised water. Instead of conventional cross-linkers such as divinyl benzene, 1,3-butanediol dimethacrylate was used as a flexible co-monomer. Morphological and mechanical properties of the porous composites with an initial pullulan loading ranging from 1 to 10 wt % have been investigated. Resulting composites were tested in terms of uniaxial compression stress and it was found out that the use of pullulan and flexible comonomer in the HIPE preparation increases the compression modulus from 13.53 to 30.8 MPa. Textural analyses of the resulting composites show that in all cases open cellular foams composed of primary cavities (112-74 lm) connected with secondary interconnected pores were produced with a specific surface area in the range of 1.7-3.0 m 2 g 21 . In addition, the influence of using porogen in the oil phase was investigated. It was found that using a porogen reduces the cavity size diameter from 112 to 20 mm and increases the compression modulus from 13.53 to 47.06 MPa.

Adsorptive polyHIPE composites based on biosorbent immobilized nanoclay: Effects of immobilization techniques

“…The external phase of the HIPEs consists of crosslinkers together with monomers, and this continuous phase is usually stabilized against droplet coalescence by the different type of surfactants such as non‐ionic, anionic, cationic, or a mixture of them. Their concentration generally ranges between 5 and 50 vol% . Although surfactants provide effective emulsion stabilization and desired porous morphology, their relatively high cost is a disadvantage in the process, especially while using them at high loadings.…”

Preparation of polyHIPE nanocomposites: Revealing the influence of experimental parameters with the help of experimental design approach

“…[ 13 ] In this frame, scientists have been focused on improving mechanical properties and increasing specific surface area to make polyHIPEs good candidates for real industrial applications. Research studies related to improving mechanical properties can be classified under three titles: (a) using lower internal phase ratios during emulsion preparation [ 14,15 ] ; (b) using stress reducer or impact modifier monomers, [ 15–18 ] and (c) inclusion of various reinforcing nanoparticles into emulsion. [ 10,11,18–20 ] Inclusion of nanoparticles not only serve for the improvement of mechanical properties, but nanoparticles can also add functionality to the final polyHIPE material [ 3,21,22 ] and/or participate in crosslinking through their active sites.…”

“…[ 10,11,18–20 ] Inclusion of nanoparticles not only serve for the improvement of mechanical properties, but nanoparticles can also add functionality to the final polyHIPE material [ 3,21,22 ] and/or participate in crosslinking through their active sites. [ 23,24 ] On the other hand, using porogens [ 12,17,25 ] in the continuous phase, or hyper‐crosslinking [ 26,27 ] of the resulting polyHIPEs are the known approaches for increasing the surface area. In general, these attempts related to improving properties were led a significant progress in terms of characteristic properties and applications of polyHIPEs.…”

Facile Visible‐Light‐Induced Preparation and Hydrophobization of Porous polyEGDMA and polyTEGDMA Thick Monoliths

“…There are two fundamentally different techniques—thermal and photochemical one that are commonly used to preparation and modification of porous polymers. Thermally activated processes allow operating with the entire volume of thin or thick porous polymer materials ; however, they do not give any possibility to change locally the obtained material properties. Contrariwise, the photochemically activated processes provide an opportunity to create the patterns with different functionality in a porous material .…”