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Properties of Polymer Dispersions

Swedish, Turkish) and emulsions (Arabic, Chinese, Enghsh, Indonesian, Italian, Malay). Another reason for the use of emulsion or emulsion polymer comes from the most important production process for these products, the emulsion polymerization. The products are referred to as emulsion polymers or simply emulsions. [Pg.3]

In contrast to this the name latex (Latin latex, liquid Greek A-ata, droplet) is derived from the naturally occurring rubber milk and is most widely used for aqueous synthetic organic polymer colloids, especially for the substitution products of natural latex, butadiene-styrene copolymer emulsions. [Pg.3]

To obtain highly stable polymer dispersions, the particles are usually provided with ionic groups, for example by adsorption of anionic or cationic surfactants, or by incorporation of ionic groups into the polymer. Another, nonionic type of stabilization takes place via hydrophilic groups on the particle surface, for example by amino-or hydroxyl-containing monomers or protective colloids. Polymer dispersions used in industry usually are stabilized by both mechanisms (ionic and nonionic). The special nature of the particle surface, which differs from the particle interior, plays an important role in all applications. [Pg.3]

Industrially important polymer dispersions usually contain 40-60 % of polymer in water. Each mL of dispersion contains about 10 particles with diameters of 50-500 nm. One particle contains 1-10 000 macromolecules, and each macromolecule contains about 100-10 monomer units (Fig. 1-2). [Pg.3]

These figures give an impression of the possible variation, if just the molecular weight (or molecular weight distribution) and particle size (or particle size distribution) of homo-polymers will be considered. The random incorporation of various monomers in the chains, the possibility of cross-linking between the polymer chains and finally separated phases of different polymers in a particle allow a virtually un-Hmited variety in this product class. [Pg.4]


All of these intermolecular forces influence several properties of polymers. Dispersion forces contribute to the factors that result in increased viscosity as molecular weight increases. Crystalline domains arise in polyethylene because of dispersion forces. As you will learn later in the text, there are other things that influence both viscosity and crystallization, but intermolecular forces play an important role. In polar polymers, such as polymethylmethacrylate, polyethylene terephthalate and nylon 6, the presence of the polar groups influences crystallization. The polar groups increase the intensity of the interactions, thereby increasing the rate at which crystalline domains form and their thermal stability. Polar interactions increase the viscosity of such polymers compared to polymers of similar length and molecular weight that exhibit low levels of interaction. [Pg.76]

Aqueous emulsions of styrene, methyl methacrylate, methyl acrylate, and ethyl acrylate were polymerized with y-radiation from a Co source in the presence of sodium dodecyl sulfate or sodium laurate. The continuous measurement of conversion and reaction rate was carried out dilato-metrically. The acrylates polymerized fastest and the over-all polymerization rate increased as follows styrene < methyl methacrylate < ethyl acrylate methyl acrylate. The effects of radiation dose, temperature, and original monomer and emulsifier concentrations were studied with respect to the following factors properties of polymer dispersions, number and size of polymer particles, viscometrically determined molecular weights, monomer-water ratio, and kinetic constants. [Pg.60]

Ferroelectric composites are alternatives to standard piezoelectric and pyroelectric ceramics such as lead zirconate titanate (PZT) and BaHOs (BT). They combine the strong ferroelectric and dielectric properties of ceramics with the easy processing and good mechanical properties of polymers. Dispersion of micrometer-sized ferroelectric particles in an electrically passive epoxy matrix was first published by Furukawa et al. [1976] and later extended to ferroelectric matrices such as poly(vinylidene fluoride) (PVDF) and poly(vinylidene fluoride-co-3-fluoroethylene) (PVDF-TrFE) [Hsiang et al., 2001 Hilczer et al., 2002 Gimenes et al., 2004 Lam et al., 2005 Beloti et al., 2006]. However, the necessity of miniaturization of electronic components and... [Pg.538]

Electrooptical Properties of Polymer Dispersed Liquid Crystal Films... [Pg.215]

Kim Jaeyong, and Han Jeong In. Effect of liquid crystal concentration on electro-optical properties of polymer dispersed liquid crystal lens for smart electronic glasses with autoshading and auto-focusing function. Electron. Mater. Lett. 10 no. 3 (2014) 607-610. [Pg.136]

Table 13 Essential properties of polymer dispersion biocides... Table 13 Essential properties of polymer dispersion biocides...
However, given the required properties of polymer dispersion biocides it is unlikely that there will ever be a true universal preservative . Development costs and regulatory and registration restrictions will prevent the development of novel molecules for polymer dispersion preservation and producers will continue to concentrate on the formulation of a number of active agents that together may fulfil the requirements of the ideal biocide. [Pg.247]

D. A. Hi ins, Probing the mesoscopic chemical and physical properties of polymer-dispersed hquid crystals. Adv. Mater. 12, 251-264 (2000). [Pg.385]

Osmond, DWJ, Wagstaff, I. Properties of polymer dispersions prepared in organic liquids. In Barrett KEJ, editor. Dispersion Polymerization in Organic Media. Chichester John WUey Sons 1975. p 243-271. [Pg.77]

Zheng, Z., Ma, J., Li, W., Song, J., Liu, Y., Xuan, L. Improvements in morphological and electro-optical properties of polymer-dispersed liquid crystal grating using a highly fluorine-substituted acrylate monomer. Liq. Cryst. 35, 885-893 (2008)... [Pg.400]

Lahiri T, Pal Majumder T (2012) The effect of cross-linked chains of polymer network on the memory states of polymer stabilized ferroelectric molecules. Polymer 53 2121-2127 Lee K, Suh SW, Lee SD (1994a) Fast linear electro-optical switching properties of polymer-dispersed ferroelectric liquid crystals. Appl Phys Lett 64 718 Lee K, Suh SW, Lee SD, Kim CY (1994b) Ferroelectric response of polymer-dispersed chiral smectic C liquid crystal composites. J Korean Phys Soc 27(1) 86... [Pg.165]

The flow behavior is also an important parameter. The flow property of polymer dispersions is a particular advantage of this aggregate state. Dispersions can have a polymer content which is a multiple higher than polymer solutions, yet stiU be free-flowing. Besides the polymer content, particle size, particle size distribution and electrolyte content, the viscosity is also affected by dissolved constituents in the aqueous phase. The water phase of many polymer dispersions contains a whole range of water-soluble oligomers, auxiliaries and additives which contribute to the application properties as well. [Pg.4]

Jazbinsek, M., Drevensek Olenik, I., Zgonik, M., Fontecchio, A.K., and Crawford, G.P. (2002). Electro-optical properties of polymer dispersed liquid crystal transmission gratings. Mo/. Cryst. Liq. Cryst. 375 455- 65. [Pg.158]


See other pages where Properties of Polymer Dispersions is mentioned: [Pg.3746]    [Pg.230]    [Pg.237]    [Pg.386]    [Pg.194]    [Pg.649]    [Pg.455]    [Pg.3]    [Pg.3]    [Pg.5]    [Pg.7]   


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