Solution swelling

Fig. 1. Bending motion of PAANa gel in dc electric fields. PAANa gel in an NaOH solution swells at the anode side and bends toward the cathode like a bimetal... 

It is usual to consider the course of emulsion polymerization to proceed through three intervals [16,17]. The particle number increases with time in Interval I, where latex particles are being formed, and then remains constant during Intervals II and II. The monomer concentration in particles is in equilibrium with a monomer saturated aqueous solution. Swelling is limited only by the opposite force of the particle surface/water tension. Hence, the concentration of monomer in the particles is usually taken as constant up to the point where free monomer droplets disappear. In Intervals I and II, the monomer concentration... 

Montmorillonite, especially the sodium form in low-ionic strength solutions, swells consequently, centrifugation in moderately high fields is needed to separate the clay particles and the solutions. Clay suspensions were usually centrifuged with a DuPont Sorvall RC-5 refrigerated super-speed centrifuge with an angle-head... 

Fig. 7 Consolidation of a self-reinforced polymer composite by solution swelling of arranged fibres dark grey reinforcement phase). The fibres are exposed to solution, which swells the surface of the fibres. The surfaces of the swollen fibres allow the fibres to bond together when consolidated during solvent extraction. Following complete solvent extraction, the fibre cores remain bonded by the surface layer of the fibres light grey) that had been previously swollen by the solvent. More complex fibre architectures can be arranged and the technique is equally applicable any arrangement of fibres such as woven fabrics and random fibre mats...

Solution swelling High Vf since no additional matrix required no matrix distribution problems Low risk of relaxation of reinforcement Use of only one polymer type eases recycling Good fibre-matrix continuity matrix phase is sourced fi om surface of reinforcement Can be applied to commodity commercial polymer fibres or fabrics Difficult to control degree of solution swelling Relatively difficult to apply industrially... 

Cotton is hydrolyzed by hot dilute or cold concentrated acids to fonn hydrocellulose but is not affected by dilute acids near room temperature. Cotton has excellent resistance to alkalies. Concentrated alkali solutions swell cotton, but the fiber is not damaged. 

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