Polymerization compounding of polyurethane-fumed silica composites

Abstract

Polymerization Compounding (PC) offers the possibility to design composite materials by controlling the architecture of a grafted polymer on the surface of solid substrates to be incorporated in a polymer matrix. The approach consists in involving the surface of a reinforcement in a polymerization process of a polymer to be used either as a matrix in the final composite or else as a special surface treatment to enhance solid/polymer interface properties in the composite. The PC process is illustrated here with fumed silica as a solid substrate and polyurethane as a matrix. The hydroxyl sites on silica particles were reacted consecutively with a toluene diisocyanate (TDI) compound and then with either bis‐phenol‐A (BA) or hydroxy‐terminated polybutadiene (HTPB) in order to obtain the desired coating. Soxhlet extractions were conducted to confirm grafting of the polymer on the solid surface. The amount of grafted polymer was evaluated by thermogravimetric analysis. Modified particles were incorporated into HTPB/TDI compounds at concentrations as high as 25% w/w. Water absorption, thermorheological as well as mechanical properties all show clear contribution of the improved bonding between the solid phase and the binder. POLYM. ENG. SCI. 46:360–371, 2006. © 2006 Society of Plastics Engineers

Non-linear Viscoelastic Behaviour of Rubber-Rubber Blend Composites and Nanocomposites: Effect of Spherical, Layered and Tubular Fillers

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The effect of processing routes on the thermal and mechanical properties of poly(urethane‐isocyanurate) nanocomposites

“…Finally, the last group, from now on denominated as Solvmix, consists on the use of solvents to aid the dispersion of the filler and its subsequent dispersion in the polyol component with a simultaneous removal of the solvent. This route has been extensively studied by several authors . Its main advantage is associated to the resultant dispersion of the filler in the matrix.…”

Encapsulation of nanoparticles by polymerization compounding in a gas/solid fluidized bed reactor

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