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Terpolymers particles

St and divinylbenzene (DVB) were polymerized in a dispersion of acryl-amide-methacrylic acid-methylenebisacrylamide terpolymer particles (25). Fine polystyrene particles were formed in/on each seed terpolymer particle. The former was smaller by about one-twentieth than the latter. The distribution of polystyrene particles depended on the cross-link density. Different amounts of St and DVB were charged in the seeded polymerization, and the resulting composite particles were used for protein adsorption measurement to assess the hydrophobicity of the particle surface. The adsorbed amount was almost proportional to the amount of St and DVB charged. In contrast, cells were less stimulated by the 5% St-containing particle than by the 0% St-containing one, that is, the seed particle. This phenomenon is attributed to selective protein adsorption on the 5% St-containing particle (26). [Pg.655]

The molecular weight of the various product grades is controlled mainly by the reaction temperature, the overall pressure, and the partial pressure ratio of the monomers. A small amount of water (2 vol%) is added to the reaction mixture to reduce the amoimt of methanol chemically bound to the terpolymer in the form of ketal groups. The initially encountered problems of extensive reactor fouling and low bulk density of the product were overcome simultaneously by introduction of a seed powder (typically 4-10 wt% PK-EP-6) in the reactor prior to the start of the polymerization and the use of an excess of acid in the catalyst solution. Both the seed powder and the excess of acid assist agglomeration of the newly formed terpolymer particles. The required excess of acid depends on the desired molecular weight. [Pg.6229]

Although superseded by polyethylene as the world s number one plastic, polyvinyl chloride (PVC) retains its title as the most versatile of all plastics— both in the number of ways it can be processed and in the range of end products. This is due to (a) the wide variety of PVC resin types available (varying in molecular weight and distribution, homo-, co-, and terpolymers, particle size and distribution, morphology, crystallinity, etc.) and (b) the ability of PVC to be formulated with a multitude of additives, unmatched by any other plastic. [Pg.539]

Adsorption of rubber over the nanosilica particles alters the viscoelastic responses. Analysis of dynamic mechanical properties therefore provides a direct clue of the mbber-silica interaction. Figure 3.22 shows the variation in storage modulus (log scale) and tan 8 against temperature for ACM-silica, ENR-silica, and in situ acrylic copolymer and terpolymer-silica hybrid nanocomposites. [Pg.77]

Fluid loss additives such as solid particles and water-thickening polymers may be added to the drilling mud to reduce fluid loss from the well bore to the formation. Insoluble and partially soluble fluid loss additives include bentonite and other clays, starch from various sources, crushed walnut hulls, lignite treated with caustic or amines, resins of various types, gilsonite, benzoic acid flakes, and carefully sized particles of calcium borate, sodium borate, and mica. Soluble fluid loss additives include carboxymethyl cellulose (CMC), low molecular weight hydroxyethyl cellulose (HEC), carboxy-methYlhydroxyethyl cellulose (CMHEC), and sodium acrylate. A large number of water-soluble vinyl copolymers and terpolymers have been described as fluid loss additives for drilling and completion fluids in the patent literature. However, relatively few appear to be used in field operations. [Pg.10]

Controlling fluid loss loss is particularly important in the case of the expensive high density brine completion fluids. While copolymers and terpolymers of vinyl monomers such as sodium poly(2-acrylamido-2-methylpropanesulfonate-co-N,N-dimethylacrylamide-coacrylic acid) has been used (H)), hydroxyethyl cellulose is the most commonly used fluid loss additive (11). It is difficult to get most polymers to hydrate in these brines (which may contain less than 50% wt. water). The treatment of HEC particle surfaces with aldehydes such as glyoxal can delay hydration until the HEC particles are well dispersed (12). Slurries in low viscosity oils (13) and alcohols have been used to disperse HEC particles prior to their addition to high density brines. This and the use of hot brines has been found to aid HEC dissolution. Wetting agents such as sulfosuccinate diesters have been found to result in increased permeability in cores invaded by high density brines (14). [Pg.11]

When the DMAEMA content of NVP - DMAEMA copolymers was reduced from 20% to 8%, the silica fines stabilization effectiveness appeared to improve slightly. When the 80/20 NVP - DMAEMA copolymer was converted to a terpolymer containing 8% DMAEMA (CH SO, silica fines stabilization was substantially unaffected. However, stabilization of silica/kaolinite fines was greatly improved. This suggested that the interaction of polymer quaternary nitrogen atoms with anionic sites on mineral surfaces was important for the stabilization of migrating clays but a different interaction was important for the stabilization of silica fines. Calcite fines stabilization improved while hematite fines stabilization effectiveness decreased. This also indicated the nature of the adsorbed polymer - fine particle complex varied for different minerals. [Pg.220]

Non-reactive impact modifier (copolymer of ethylene and methyl acrylate). b Reactive impact modifier (terpolymer of ethylene, methyl acrylate and glycidyl methacrylate). c Interparticle distance, i.e. the average distance between particles of impact modifier in the PET matrix. [Pg.515]

Products with improved properties use instead pure PMMA a terpolymer from 1,3-butadiene, styrene, and methyl methacrylate (8). Actually, the proposed blend consists of up to 6 components of copolymers of different composition and particle diameters. [Pg.336]

Figure 12.10 Microcolumn SEC-LC analysis of an acrylonitrile-butadiene-styrene (ABS) terpolymer sample (a) SEC trace (b) LC trace. SEC conditions fused-silica column (30 cm X 250 mm i.d.) packed with PL-GEL (50 A pore size, 5 mm particle diameter) eluent, THF at a flow rate of 2.0 mL/min injection size, 200 nL UV detection at 254 nm x represents the polymer additive fraction (6 xL) transferred to LC system. LC conditions NovaPak C18 Column (15 cm X 4.6 mm i.d.) eluent, acetonitrile-water (60 40) to (95 5) in 15 min gradient flow rate of 1.5 mL/min detection at 214 nm. Peaks identification is follows 1, styrene-acrylonitrile 2, styrene 3, benzylbutyl phthalate 4, nonylphenol isomers 5, Vanox 2246 6, Topanol 7, unknown 8, Tinuvin 328 9, Irganox 1076 10, unknown. Reprinted with permission from Ref. (14). Figure 12.10 Microcolumn SEC-LC analysis of an acrylonitrile-butadiene-styrene (ABS) terpolymer sample (a) SEC trace (b) LC trace. SEC conditions fused-silica column (30 cm X 250 mm i.d.) packed with PL-GEL (50 A pore size, 5 mm particle diameter) eluent, THF at a flow rate of 2.0 mL/min injection size, 200 nL UV detection at 254 nm x represents the polymer additive fraction (6 xL) transferred to LC system. LC conditions NovaPak C18 Column (15 cm X 4.6 mm i.d.) eluent, acetonitrile-water (60 40) to (95 5) in 15 min gradient flow rate of 1.5 mL/min detection at 214 nm. Peaks identification is follows 1, styrene-acrylonitrile 2, styrene 3, benzylbutyl phthalate 4, nonylphenol isomers 5, Vanox 2246 6, Topanol 7, unknown 8, Tinuvin 328 9, Irganox 1076 10, unknown. Reprinted with permission from Ref. (14).
Fig. 21 Nucleation density vs particle density of PPE/SAN blends compatibilized by SMB triblock terpolymers, in comparison to uncompatibilized PPE/SAN blends... Fig. 21 Nucleation density vs particle density of PPE/SAN blends compatibilized by SMB triblock terpolymers, in comparison to uncompatibilized PPE/SAN blends...
Next 129Xe experiments on an EPDM terpolymer, which is present as the elastomer component in a composite material with carbon black will be discussed. The question investigated for these materials is whether the existence of any polymer-filler interaction can be detected by 129Xe NMR. This interaction influences the mobility of the elastomer chains in a relatively large shell around the filler particles. This fraction is called the bound rubber fraction. It is generally believed that the bound rubber fraction influences the mechanical and frictional properties of the filled elastomer [17, 18]. [Pg.474]

Various patents on the homopolymerization of BD in the presence of styrene are available [581-590]. According to these patents, St is used as a solvent in which BD is selectively polymerized by the application of NdV/DIBAH/EASC. At the end of the polymerization a solution of BR in St is obtained. In subsequent reaction steps the unreacted styrene monomer is either polymerized radically, or acrylonitrile is added prior to radical initiation. During the subsequent radical polymerization styrene or styrene/acrylonitrile, respectively, are polymerized and ris-l,4-BR is grafted and partially crosslinked. In this way BR modified (or impact modified) thermoplast blends are obtained. In these blends BR particles are dispersed either in poly(styrene) (yielding HIPS = high impact poly(styrene) or in styrene-acrylonitrile-copolymers (yielding ABS = acrylonitrile/butadiene/ styrene-terpolymers). In comparison with the classical bulk processes for HIPS and ABS, this new technology allows for considerable cost reductions... [Pg.98]

Figure 2. Effect of particle charge on mechanical stability (MAA terpolymer)... Figure 2. Effect of particle charge on mechanical stability (MAA terpolymer)...
Copolymer 35, generated from 19 and 8, was the first transition metal containing organometaHic polymer including one metal as a r 6-complex and the other as a r 5-complex.67 The remarkable terpolymer, 37, which contains r 4-(diene)iron, T]5-(cyclopentadienyl)man-ganese, and T)6-(styryl)chromium species in each chain, was made. Thermal decomposition in air was conducted to see if mixed metal oxide particles of novel composition could be generated, but characterization of these products was beyond our capabilities in 1972. [Pg.11]

Recently, Perro et al. [55] reviewed the developments in the field of Janus particles over the last 15 years, describing various strategies to obtain Janus-type particles using polymer precursors. One strategy is based on the self-assembly of ABC terpolymers in bulk [56, 57] or in solution [58], Another uses the electrostatic interactions of AB and CD diblock copolymers, which lead to inter-polyelectrolyte complexes [59], A different synthetic concept is to obtain Janus particles made of inorganic materials, e.g., acorn-like particles made of PdSx-CogSg [60] or... [Pg.48]


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See also in sourсe #XX -- [ Pg.182 ]




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