Colloidal characteristics

This paper presents the physical mechanism and the structure of a comprehensive dynamic Emulsion Polymerization Model (EPM). EPM combines the theory of coagulative nucleation of homogeneously nucleated precursors with detailed species material and energy balances to calculate the time evolution of the concentration, size, and colloidal characteristics of latex particles, the monomer conversions, the copolymer composition, and molecular weight in an emulsion system. The capabilities of EPM are demonstrated by comparisons of its predictions with experimental data from the literature covering styrene and styrene/methyl methacrylate polymerizations. EPM can successfully simulate continuous and batch reactors over a wide range of initiator and added surfactant concentrations. 

Accordingly, TEM investigations confirmed the NPs formation in Pt-catalysed hydrosilylation from a solution of [PtCl2(cod)]. The particles formed in situ showed a mean size of 2.3 nm. Moreover, XPS (X-ray Photoemission Spectrometry) analysis confirmed that the colloid characteristics are distinct from bulk metal and monometallic complex (binding energy for Pt bulk metal is 71.0 eV for [PtCl2(cod)], 72.45 eV and for Pt colloid, 72.24eV) [12]. 

Dobson, E. L., Finkelstein, L. J., Finney, C. R. and Kelly, L. S. (1966). Particulate chromic phosphate Colloid characteristics suitable for measurement of liver circulation, page 477 in Radioactive Pharmaceuticals, AEC Symposium Series No. 6, Report No. CONF-651111, Andrews, G. A., Kniseley, R. M. and Wagner, H. N., Jr., Eds. (National Technical Information Service, Springfield, Virginia). 

Abstract Emulsion homopolymers and copolymers (latexes) are widely used in architectural interior and exterior paints, adhesives, and textile industries. Colloidal stabihzators in the emulsion polymerization strongly affect not only the colloidal properties of latexes but also the fdm and mechanical properties, in general. Additionally, the properties of polymer/copolymer latexes depend on the copolymer composition, polymer morphology, initiator, polymerization medium and colloidal characteristics of copolymer particles. 

Colloidal Characteristics of MA and BMA Latexes Depending on Initial Concentration of Sodium AlkylSulfonate in Aqueous Phase... 

Colloidal Characteristics of Acrylate and Styrene Latexes Syrtthesized with SDDS... 

Over the past few years, there has been a growing emphasis on the understanding of the colloidal basis of properties of food emulsions, rather than just treating them as a black box whose properties could be characterized in terms of certain empirical parameters. Researchers are attempting to quantitatively relate the properties of food emulsions to the characteristics, interactions, and spatial distribution of the droplets they contain. A wide variety of analytical, mathematical, and computational techniques are being developed and utilized to achieve this objective. Powerful commercial instmments are widely available to quantify the colloidal characteristics of both dilute and concentrated emulsions, e.g., droplet size, concentration, and electrical charge (137-139). Theoretical, computational, and... 

Hawley, A.E. Davis, S.S. Ilium, L. Targeting of colloids to lymph nodes influence of lymphatic physiology and colloidal characteristics. Adv. Drug Delivery Rev. 1995, 17, 129-148. 

The colloidal characteristics of A -alkylacrylamide- or Af-alkylmethacrylamide-based particles are temperature related. In fact, the swelling ability, charge density, charge distribution, hydrophilic-hydrophobic balance, hydration and dehydration properties, particle size, surface polarity, colloidal stability, water content, turbidity, and electrokinetic and rheological properties are indis-cemibly temperature dependent. Such polymer particles can be used as a stimuli-responsive model for the investigation of colloidal properties and for theoretical studies. 

The next direct method for the determination of colloidal characteristics of crude oil is the conductive method. This method is based on the measurement of the electrical conductivity of the sample during the time the colloidal particles pass through a calibrated microhole. The schematic of the setup used for measurement by the conductive method is shown in Figure 2.63. 

Overall, the LJF experiments indicated thatflux is very dependent on the structure of the deposit, which was determined by the solute or colloid characteristics and their interaction in suspension. Organic ryection is more reliable for tighter membranes (10 kDa) and flux is more stable. Coagulation pretreatment can improve flux and rfiction, however the... 

Table A3.1 Hematite preparation procedures and colloid characteristics, ferric chloride floe characteristics for comparison. ...

Liposomes can be made entirely from naturally occurring substances, and are therefore biodegradable and nonimmunogenic. In some cases, the introduction of synthetic lipids is useful for specific characteristics such as stability and charge. The lipid composition, colloidal characteristics, and surface modifications also allow liposomes to have functional properties, such as stability, controlled release of the encapsulated molecules, specific targeting, and controlled pH and temperature sensitivity. 

Fig. 14 Colloidal characteristics of the polyAA-stabilized particles prepared by surfactant-free nitroxide-mediated emulsion polymerization of styrene (a) pH-dependence of the diameters ( ), (b) stability of the polystyrene particles with pH, and (c) influence of the initial polyAA-SGl concentration and of the target degree of polymerization, )Pn,th, on the particle diameter...

This paper is the seventh in a series discussing colloid chemistry, and focuses on latex paints. These are defined, and then discussed under the following headings terminology, general features, inherent contradictions, emulsion paints as latex-based compositions, latex characterisation, colloid characteristics, latex modification, latex stability, latex paints as polymers and pigment mixed dispersions, functional additives, and paint stability. 5 refs. 

Tawa, T Ito, S. The role of hard segments of aqueous polyurethane-urea dispersion in determining the colloidal characteristics and physical properties. Polymer Journal,... 

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