Polymer blend

About: Polymer blend is a research topic. Over the lifetime, 18474 publications have been published within this topic receiving 437183 citations. The topic is also known as: polymer mixture & Polymerblend 或者 Polyblend.

Filler blend of carbon nanotubes and organoclays with improved char as a new flame retardant system for polymers and cable applications

Abstract: Multi wall carbon nanotubes (MWCNTs) or single wall carbon nanotubes (SWCNTs) were used as fillers in polyethylene (PE). Only MWCNTs reduced the heat release rates caused by polymer degradation. MWCNTs can be more effective in heat release reduction than organoclays. The char generated by the filler blend 'MWCNTs and organoclays' as a synergistic flame retardant system in an ethylene vinylacetate (EVA) based polymer blend was improved compared with the char generated by the only organoclay based nanocomposite. Initial results indicated that there was a strengthening effect of the char by MWCNTs. The synergistic improvement for heat release reduction by a blend of the two fillers 'MWCNTs and organoclays' was used for the development of a flame retardant cable compound. 1.5 kg of MWCNTs was compounded on a Buss ko-kneader to generate 60 kg of a nanocomposite based on the filler blend. The flame retardant properties of insulated wires made either by the filler blend or by 'classical' organoclays were measured.

The Thermodynamics of High‐Polymer Solutions: I. The Free Energy of Mixing of Solvents and Polymers of Heterogeneous Distribution

Abstract: The theories of Flory and Huggins for the free energy of mixing of a homogeneous chain polymer of uniform molecular weight with a single uniform solvent have been extended to the case of a polymer mixture of varying chain lengths with a mixture of solvents. By making the similar assumptions as those of Huggins, and utilizing familiar statistical mechanical methods, the partial molal free energy of mixing of the solvent is found to be ΔF0¯=RT[ln φ0+(1−φ0)(1–1/mN)+μ(1−φ0)2], where φ0 is the volume fraction of solvent, mN a simple function of the number average molecular weight, and μ a constant characteristic of the polymer‐solvent mixture (consisting largely of a heat term, but also including γ, the coordination number of the rubber segments). By assuming that a mixture of two solvents behaves like a new homogeneous liquid a method of calculating μ for such mixtures is developed. Applications of these formulas to solubility and fractionation are shown in a subsequent article.

Polymer Blends in Membrane Transport Processes

Abstract: Polymer blend technology and gas membrane separation have been two research areas where Prof. Don Paul has had major contributions. The combination of these topics has been chosen as the subject of this review paper. The morphology of phase separated polymer blends is an important variable in the design of enhanced transport properties. The fundamentals of polymer blends in transport processes will be discussed along with situations where polymer blends may be desired. These areas include barrier polymers, gas membrane separation, percolation networks for electrical conductivity, proton exchange membranes, and polymers employed in optoelectronic devices. The predictions of the series, parallel, Maxwell, and equivalent box models are applied where relevant to these examples.