Surface modification of polybutadiene facilitated by supercritical carbon dioxide

Abstract

ABSTRACT:The hydrophilicity of polymers can be improved through surface modification, traditionally done with conventional organic solvents, but these may cause the deterioration of polymer bulk properties due to irreversible polymer swelling. However, supercritical carbon dioxide (scCO 2 ) not only swells the polymer reversibly, but also acts as a convenient transport medium for monomeric solutes, which may be subsequently polymerized. Thus we are able to modify the polymer surface without affecting its bulk strength and durability. Here we report scCO 2 surface modification of polybutadiene using ultraviolet-visible (UV/Vis) and Fourier transform infrared (FTIR) spectroscopy. Monomers such as 3-vinylbenzoic acid and crotonic acid are used to study the effects of pressure, solute structure, and reaction mechanism on the diffusion rates and partitioning of monomers between the fluid phase and the polymer.

Supercritical carbon dioxide as a green solvent for processing polymer melts: Processing aspects and applications

“…Dissolution of CO 2 in a polymer facilitates diffusion of monomers and catalysts/initiators within the polymer matrix. In this case, CO 2 is the carrier of active chemical species [101] as well as the swelling agent. Accordingly, chemical modification of polymers can be carried out in milder conditions than with standard methods of melt modification in extruders or batch mixers.…”

Head drop syndrome secondary to multimodality treatments for head and neck cancer

“…If the solute is a reactive monomer, the SC‐CO 2 ‐assisted impregnation can be followed by polymerizations, and so it is possible to prepare a massive composite15–18 or a surface‐modified organic polymer compound19–21 or to induce the grafting of suitable polar monomers onto the polymer backbone 22…”

Grafting of Maleic Anhydride onto Isotactic Polypropylene in the Presence of Supercritical Carbon Dioxide as a Solvent and Swelling Fluid

“…13,14 At a properly chosen value of the density, scCO 2 can dissolve low polar compounds and interact with the polymer, both plasticizing and swelling the matrix; upon release of pressure, precipitation of the finely dispersed solute into the polymer structure occurs thus allowing impregnation of the substrate. 14 If the solute is a reactive monomer, the scCO 2assisted infusion can be followed by polymerization, and through this route, it is possible to prepare a massive composite [15][16][17][18][19][20][21] or a surface-modified organic polymer compound [22][23][24] or to induce grafting of suitable polar monomers onto the polymer backbone. 25,26 Our research group has previously investigated the modification of iPP with maleic anhydride by using supercritical CO 2 as a solvent and carrier agent to deliver the monomer into the bulk polymer, performing an ex situ γ radiation initiated grafting of the solubilized † Current address: STMicroelectronics Srl, Stradale Primosole, 50 95121 Catania, Italy.…”

“…If the solute is a reactive monomer, the scCO 2 -assisted infusion can be followed by polymerization, and through this route, it is possible to prepare a massive composite − or a surface-modified organic polymer compound − or to induce grafting of suitable polar monomers onto the polymer backbone. , …”