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To determine if the parameters of two molecules (usually a solvent and a polymer) are within range, a value called interaction radius is given to the substance being dissolved. This value determines the radius of the sphere in Hansen space and its center is the three Hansen parameters.
Another application of polymer solutions includes the manufacture of fibers by wet or dry spinning or plastic films. Disadvantages of solution polymerization are decrease of monomer and initiator concentration leading to reduction of reaction rate, lower volume utilization of reactor, additional cost of the process related to solvent recycling ...
Flory–Huggins solution theory is a lattice model of the thermodynamics of polymer solutions which takes account of the great dissimilarity in molecular sizes in adapting the usual expression for the entropy of mixing. The result is an equation for the Gibbs free energy change for mixing a polymer with a solvent. Although it makes simplifying ...
A solvent is usually a liquid but can also be a solid, a gas, or a supercritical fluid. Water is a solvent for polar molecules, and the most common solvent used by living things; all the ions and proteins in a cell are dissolved in water within the cell. Major uses of solvents are in paints, paint removers, inks, and dry cleaning. [2]
These may be liquid solutions (e.g. in aqueous solution), or solid solutions (e.g. a substance which has been plasticized). [2] The introduction into the polymer of small amounts of a solvent (plasticizer) reduces the temperature of glass transition, the yield temperature, and the viscosity of a melt.
In polymer science, dispersion polymerization is a heterogeneous polymerization process carried out in the presence of a polymeric stabilizer in the reaction medium. . Dispersion polymerization is a type of precipitation polymerization, meaning the solvent selected as the reaction medium is a good solvent for the monomer and the initiator, but is a non-solvent for the po
Due to the low entropy of mixing, miscibility gaps are often observed for polymer solutions. [11] Many polymers are known that show UCST or LCST behavior in organic solvents. [39] Examples for organic polymer solutions with UCST are polystyrene in cyclohexane, [37] [40] polyethylene in diphenylether [41] [42] or polymethylmethacrylate in ...
Beginning with a mixture of polymer and solvent (top), cosolvents encourage the aggregation of polymers (right), simplifying production and improving performance. Without the use of cosolvent, droplets of primary solvent coalesce into distinct domains and polymer is more randomly dispersed (left). Adapted from Janssen et al (2015).