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Blends polyacrylates

Similar results were obtained in the pervaporation separation of acetic acid-water mixtures using blended polyacrylic acid-nylon 6 membranes [22], poly(4-vinylpyridine-co-aciylonitrile) membranes [11] and in the permeation and separation of aqueous alcohol solutions through PVA-AN-HEMA latex membranes [5],... [Pg.55]

Decabromododiphenyl Oxide—Polyacrylate Finish. This finish, effective on both polyester and nylon fabrics, is one of the most effective finishes available (ca 1993) for cotton—polyester blends (131). Relatively high cost and difficulty in appUcation may have prevented more widespread use. [Pg.491]

Examples of photothermoplasts include polyacrylates, polyacrylamides, polystyrenes, polycarbonates, and their copolymers (169). An especially well-re searched photothermoplast is poly(methyl methacrylate) (PMMA), which is blended with methyl methacrylate (MMA) or styrene as a monomer, and titanium-bis(cyclopentadienyl) as a photoinitiator (170). [Pg.154]

Dimercapto-l,3,4-thiadiazole derivatives, accelerated by amines, are used to cross-link chlorinated polyethylene. Polyisobutylene containing brominated i ra-methylstyrene cure functionahty can be cross-linked in polymer blends with dimercapto-1,3,4-thiadiazole derivatives accelerated with thiuram disulfides. Trithiocyanuric acid is suggested for use in polyacrylates containing a chlorine cure site and in epichlorohydrin mbbers. [Pg.225]

Standard-grade PSAs are usually made from styrene-butadiene rubber (SBR), natural rubber, or blends thereof in solution. In addition to rubbers, polyacrylates, polymethylacrylates, polyfvinyl ethers), polychloroprene, and polyisobutenes are often components of the system ([198], pp. 25-39). These are often modified with phenolic resins, or resins based on rosin esters, coumarones, or hydrocarbons. Phenolic resins improve temperature resistance, solvent resistance, and cohesive strength of PSA ([196], pp. 276-278). Antioxidants and tackifiers are also essential components. Sometimes the tackifier will be a lower molecular weight component of the high polymer system. The phenolic resins may be standard resoles, alkyl phenolics, or terpene-phenolic systems ([198], pp. 25-39 and 80-81). Pressure-sensitive dispersions are normally comprised of special acrylic ester copolymers with resin modifiers. The high polymer base used determines adhesive and cohesive properties of the PSA. [Pg.933]

Variation of melt viscosity for both the preblends and preheated blends with the blend ratio are shown in Fig. 19. There are two distinct regions in viscosity change with the addition of polyacrylic rubber (ACM) in the blends. First, in the higher shear rate region, the viscosity increases with the addition of the ACM (up to 40% ACM) in the blend and then it decreases. In the lower... [Pg.617]

Engineering polymers are often used as a replacement for wood and metals. Examples include polyamides (PA), often called nylons, polyesters (saturated and unsaturated), aromatic polycarbonates (PCs), polyoxymethylenes (POMs), polyacrylates, polyphenylene oxide (PPO), styrene copolymers, e.g., styrene/ acrylonitrile (SAN) and acrylonitrile/butadiene/styrene (ABS). Many of these polymers are produced as copolymers or used as blends and are each manufactured worldwide on the 1 million tonne scale. [Pg.66]

The three major types of raw materials used in superplasticizers, SNF, SMF, and polyacrylates are shown in Fig. 2.1, which also illustrates the three different types of polyacrylates. Minor amounts of other materials are often added such as triethanolamine (to counteract retardation), tributyl phosphate (to cut down excessive air entrainment) and hydroxycarboxylic acid salts or lignosulfonates (to increase retardation). In addition proprietary superplasticizers can be blends of two of the main ingredients. [Pg.125]

Synthetic muscle systems were first mentioned by Flory in 1953 and defined in the context of this chapter by Kuhn et al. 5° Flory described the effect of temperature on a polyacrylic acid-polyvinyl alcohol blend. Kuhn studied pH, temperature, and ionic strength stimuli. Tanaka et al. made a significant contribution to the technology in an experiment that combined the contraction-relaxation phenomenon with stimuli developed indirectly by an electric current. Their work resulted in a patent. ... [Pg.177]

Flame relardanls are used in smolder-resistant upholstery fabric, combination flame retardant-durable press performance, flame-retardant treatments for wool, thermoplastic fibers (Tris. decabromodiphenyl oxide-polyacrylate finishes. Antihlu/e 19. nylon finishes), polyester-cotton fiber blends (THPOH-ummonju-Tris finish, decabromodiphenyl oxide-polyacrylate finish. THPC-amide-polytv illy I bromide) finish, THPOH-NHi and Fyrol 76. LRC-UX) finish, phusphonium salt-urea precondcn-satej. cotton-wool blends, and core-yam fabric,... [Pg.642]

The use of an electric field is not the only effective way to influence the LC polymer structure, magnetic fields displays a closely similar effect167 168). It is interesting as a method allowing to orient LC polymers, as well as from the viewpoint of determining some parameters, such as the order parameter, values of magnetic susceptibility, rotational viscosity and others. Some relationships established for LC polymer 1 (Table 15), its blends with low-molecular liquid crystals and partially deuterated polyacrylate (polymer 4, Table 15) specially synthesized for NMR studies can be summarized as follows ... [Pg.238]

Where experience with water chemistry, system metallurgy, or system operation suggests that only minimal waterside problems may occur, or where customer demands are for minimal expenditure, inhibitor treatments may consist of only simple formulations, such as a phosphonate/polyacrylate blend. Many cooling systems around the world, both large and small, do in fact operate on little more than just this type of simple low-cost approach. However, for the most part, the operators face an uphill battle to maintain operational efficiency, and many are unaware of the benefits to be gained by using a more comprehensive treatment program. [Pg.304]

Superabsorbent polymers are now commonly made from the polymerization of acrylic acid blended with sodium hydroxide in the presence of an initiator to form a polyacrylic acid, sodium salt (sometimes referred to as cross-linked sodium polyacrylate). Some of the polymers include polyacrylamide copolymer, ethylene maleic anhydride copolymer, cross-linked carboxy-methyl-cellulose, polyvinyl alcohol copolymers, cross-linked polyethylene oxide, and starch grafted copolymer of polyacrylonitrile to name a few. The latter is one of the oldest SAP forms created. [Pg.32]

A few papers dealing with silicone latex IPNs have appeared. Frisch et al. [ 111 ] patented a process whereby two emulsions were prepared the first contained a hydroxyl-terminated PDMS and stannous octoate, the second a crosslinked polyurethane, poly(urethaneurea) or polyacrylate latex. The two lattices were blended and a film was cast and cured at 120 °C. The mechanical properties were found to be enhanced, especially in the case of the polyacrylate/PDMS IPN. Noteworthy is the fact that semi-IPNs such as the thermally stable... [Pg.135]

Dewetting of an Incompatible Polymer Blend on a Gold Surface Polyacryl-co-Styrene and Polybutadiene... [Pg.187]

Early antisealants used sodium hexametaphosphate (SHMP) as a threshold agent to inhibit the growth of calcium carbonate and sulfate-based scales.6 Most antisealants on the market today contain sulfonate, phosphate, or carboxylic acid functional groups. Perhaps the most effective antisealants today contain and blend of polyacrylic acid (PAA) and phosphoric acid or polyacrylate and a hydroyethylidene diphosphonate (HEDP).12 The polyacrylate-HEDP blends also claim to have good dispersion qualities toward silts and clays.12 Some new inhibitors include a chelant and disper-ant to keep suspended solids such as iron and manganese oxides in solution. These newer antisealants are generally more effective than SHMP for a variety of potential scales.6... [Pg.178]

Organic peroxides are used to initiate free-radical polymerization of ethylene, butadiene, styrene, vinyl chloride, vinyl acetate, and methyl methacrylate. They are also used to cure unsaturated polyesters, occasionally to cross-link thermoplastics such as polyethylene and polyacrylates, and increasingly for grafting and compatibiliza-tion of polymer blends. A variety of organic peroxides offer useful reactivity over a temperature range from 0 to 130°C or more, for different polymers and different processes. [Pg.664]

Other examples of solvent effects in casting blends include epoxy resin/copoly-ester/tetrachloroethane polyethersulphone/poly(ethylene oxide)/cyclohexanone and mixtures of PVC with various polyacrylates in solvents such as THF One particular pair of polymers PVC/poly(ethyl acrylate) appear to be miscible but no suitable solvent has been found as yet. Homogeneous blends can only be prepared by in situ polymerisation though it is possible that miscibility is enhanced by small amounts of graft copolymer which is inevitably formed by this technique. [Pg.131]

PERAPRET D and PERAPRET DS are anionic polyacrylate dispersions with low viscosity. They have a solids content of approx. 25% and a pH of 2-3. They are both used to facilitate the removal of soil from textiles, particularly blends of cellulosic and synthetic fibres, under normal conditions of household washing. They are, therefore, applied as additives in soil-release finishing. The treating liquor must, of course, only contain products that do not impair this desired effect. [Pg.89]

The effect of temperature on the flow behaviour of polymethacrylate and polyacrylate blends in mineral oil demonstrated that it is strongly controlled by the entropy of activation for viscous flow [51], confirming early speculations [52]. The increased negative entropy was presumably a result of the very sluggish translational motion of the polymer coils. On the other hand, the enthalpy of activation for viscous flow of the polymer solutions was, for the most part, very nearly the same as that of the oil solvent. Only the most efficient systems exhibited decreased enthalpy, suggesting that coil expansion at high temperatures may be a factor, but the effect was very small relative to the entropy effect. [Pg.167]


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See also in sourсe #XX -- [ Pg.152 , Pg.153 , Pg.155 ]

See also in sourсe #XX -- [ Pg.152 , Pg.153 , Pg.155 ]




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