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Copolymers of polyacrylates

Photochromic materials with liquid-crystal polymer40 2 are interesting advanced materials, due to their sensitivity to light, electric, and magnetic fields. Copolymers of polyacrylic or polysiloxane backbone, con-... [Pg.21]

Figure 3.23 The tertiary electroviscous effect observed for particles of polystyrene latex with a copolymer of polyacrylic acid at the outer surface. The experimental points were obtained at pH 3 and 10. The dry particle radius was 75 nm and Ka 25... Figure 3.23 The tertiary electroviscous effect observed for particles of polystyrene latex with a copolymer of polyacrylic acid at the outer surface. The experimental points were obtained at pH 3 and 10. The dry particle radius was 75 nm and Ka 25...
Formation of hydrophobically associated copolymers of polyacrylic acid with long-chain amines by use of a carbodiimide [129]. [Pg.345]

Low molecular weight (1000—5000) polyacrylates and copolymers of acryflc acid and AMPS are used as dispersants for weighted water-base muds (64). These materials, 40—50% of which is the active polymer, are usually provided in a Hquid form. They are particularly useful where high temperatures are encountered or in muds, which derive most of their viscosity from fine drill soHds, and polymers such as xanthan gum and polyacrylamide. Another high temperature polymer, a sulfonated styrene maleic—anhydride copolymer, is provided in powdered form (65,66). AH of these materials are used in relatively low (ca 0.2—0.7 kg/m (0.5—2 lb /bbl)) concentrations in the mud. [Pg.180]

Evidence for the firm binding of Zn comes from studies using labelled zinc polyacrylate containing Zn and C. Only small amounts of these ions were lost to a saline solution over a three-month period, even in the presence of calcium (Peters et al., 1972 Peters, Jackson Smith, 1974). There is some evidence, from leaching studies, that Zn is more firmly bound to a copolymer of acrylic and itaconic adds than to poly(acrylic acid), and less firmly bound to a copolymer of maleic and acrylic adds. [Pg.106]

Emulsion paints are based on aqueous synthetic resin dispersions, which afford a lacquer-like paint film. The resin dispersions which are commonly used by the paint industry contain water as the carrier phase. A large number of such dispersions are available, based on different resins such as poly(vinyl acetate), which may be employed as a copolymer with vinyl chloride, maleic dibutyl ester, ethylene, acrylic acid esters, polyacrylic resin, and copolymers of the latter with various monomers, as well as styrene-butadiene or poly(vinyl propionate). These disper-... [Pg.159]

The dyes with long-lived luminescence are particularly attractive since background fluorescence can easily be discarded in time domain measurements. Crosssensitivity to oxygen may be problematic but it can be minimized by utilizing gas-blocking polymers. For example, Kuemer et al. [15] used the precipitation technique to prepare polyacrylonitrile-based beads doped with a ruthenium(II) complex which showed virtually no cross-sensitivity to oxygen. Copolymers of polyacrylonitrile and polyacrylic acid were used to provide the beads with... [Pg.212]

Another interesting positive-tone polyacrylate DUV resist has been reported by Ohno and coworkers (82). This material is a copolymer of methyl methacrylate and glycidyl methacrylate. Such materials are negative e-beam resists, yet in the DUV they function as positive resists. Thermal crosslinking of the images after development provides relief structures with exceptional thermal stability. The reported sensitivity of these copolymers is surprising, since there are no obvious scission mechanisms available to the system other than those operative in PMMA homopolymer, and the glylcidy side-chain does not increase the optical density of the system. [Pg.152]

The percent inhibition was calculated according to the equation in Table II. As shown in Table II, the results indicated that when compared to the polyacrylic acid, copolymers of acrylic acid and N-(hydroxyalkyl)-acrylamide were quite effective in inhibiting calcium phosphate formation at the normal use dosage of 10 to 20 ppm. Among the three copolymers tested, acrylic acid/... [Pg.286]

In this work, we have chosen several systems stabilized through hydrogen bonds. The homopolymer is a polybase, i.e. PEO, PVME or PVP, and the copolymer is polyacrylic acid with various degrees of neutralization a, in which the acrylates are the non active groups. Complex formation is studied by potentiometry (because complexation induces a variation of the solution pH) and by viscometry and polarized luminescence which respectively give information about the macroscopic and local structure of the complex in solution. The influence of parameters such as the degree of neutralization of PAA a, the concentration ratio r - [polybase]/[PAA], the concentration and the molecular weight of polymers is examined. [Pg.73]

PMA is a tough leathery resin with a low Tg and a solubility parameter of 10.5 H. In polymers of alkyl acrylates the solubility parameter decreases as the size of the alkyl group increases. The flexibility also increases with the size of the pendant groups but because of side chain crystallization this tendency is reversed when the alkyl group has more than ten carbon atoms. Polyalkyi acrylates are readily hydrolyzed by alkalis to produce salts of polyacrylic acid. The copolymer of ethyl acrylate (95%) and chloroethyl vinyl ether (5%) is a commercial oil-resistant elastomer. [Pg.158]

Copolymer of styrene and acrylonitrile Copolymer of styrene and butadiene Natural rubber Chlorinated polyethylene Chlorosulfonated polyethylene Polyamides Polyesters Polyurethanes Polysulfones Polyacrylates Polyacrylamides Polydimethylsiloxane Copolymer of vinylidene fluoride and hexafluoropropylene... [Pg.86]

HMX HMX HMX HMX HMX HMX HMX HMX HMX HMX HMX HMX HNS NTO NTO/HMX NTO/HMX NTO/HMX PETN PETN PETN PETN PETN PETN PETN PETN PETN PETN RDX RDX RDX RDX RDX RDX RDX RDX RDX RDX RDX RDX RDX TATB/HMX Cariflex (thermoplastic elastomer) Hydroxy-terminated polybutadiene (polyurethane) Hydroxy-terminated polyester Kraton (block copolymer of styrene and ethylene-butylene) Nylon (polyamide) Polyester resin-styrene Polyethylene Polyurethane Poly(vinyl) alcohol Poly(vinyl) butyral resin Teflon (polytetrafluoroethylene) Viton (fluoroelastomer) Teflon (polytetrafluoroethylene) Cariflex (block copolymer of butadiene-styrene) Cariflex (block copolymer of butadiene-styrene) Estane (polyester polyurethane copolymer) Hytemp (thermoplastic elastomer) Butyl rubber with acetyl tributylcitrate Epoxy resin-diethylenetriamine Kraton (block copolymer of styrene and ethylene-butylene) Latex with bis-(2-ethylhexyl adipate) Nylon (polyamide) Polyester and styrene copolymer Poly(ethyl acrylate) with dibutyl phthalate Silicone rubber Viton (fluoroelastomer) Teflon (polytetrafluoroethylene) Epoxy ether Exon (polychlorotrifluoroethylene/vinylidine chloride) Hydroxy-terminated polybutadiene (polyurethane) Kel-F (polychlorotrifluoroethylene) Nylon (polyamide) Nylon and aluminium Nitro-fluoroalkyl epoxides Polyacrylate and paraffin Polyamide resin Polyisobutylene/Teflon (polytetrafluoroethylene) Polyester Polystyrene Teflon (polytetrafluoroethylene) Kraton (block copolymer of styrene and ethylene-butylene)... [Pg.12]

With the exception of local main-chain motions, the above-mentioned types of molecular motions have been investigated on a series of hydrophilic polymethacrylates and polyacrylates by means of dynamic mechanical measurements carried out with a torsional pendulum. For this purpose, the constitution of polymethacrylates was systematically altered and correlated with the dynamic mechanical response spectra. It was established for a series of copolymers of poly(2-hydroxyethyl methacrylate) that the temperature of the y relaxation (140 K 1 Hz), assigned to the motion of 2-hydroxyethyl... [Pg.155]

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]

Polyacrylic acid was chosen as the stabilising moiety because there is a substantial body of literature on its solution properties and because Napper (12) has demonstrated a correlation between critical flocculation temperature and 0-temperature for particles stabilised by copolymers of unionised PAA. Also, since PAA is a weak acid the degree of ionisation can be varied by titration with base. [Pg.161]

Very recently, these processes were extended for the generation of helical morphologies of K2SO4 crystals [38] generated in the presence of polyacrylic acid, Fig. la,b, and for the preparation of helices from the achiral BaC03 nanocrystals [39,40] grown in the presence of racemic hydrophilic block copolymers. [Pg.127]

For the packaging of sensitive foods, PP films are coated with polyvinylidene chloride, polyvinyl acetate, EVAcopolymers, polyacrylates, styrene-butadiene copolymers, LDPE, poly-l-butene or random copolymers of propene with ethylene and 1-butene. By using these various coatings PP has recently sharply reduced the use of regenerated cellulose (cellophane), the previous market leader in this area. [Pg.26]

The highest sonic damping is obtained in transition zones. The glass transition can be used for this purpose if cross-linked polymers are applied, with a rubbery solid state until far above Tg. Very interesting work in this field was done by Sperling and his coworkers (1987,1988) who studied the damping behaviour of homopolymers, statistical copolymers and interpenetrating networks (IPNs) of polyacrylics, polyvinyls and polystyrenes. [Pg.518]

In the poly(ethyl acrylate)rubbers described above spirobenzopyran and aromatic azo chromophores were incorporated in the cross-links between the polyacrylic chains. In contrast, Matejika and al. studied cross-linked systems with azo side groups they considered especially the relative importance of the thermal effects occurring during photomechanical conversion. Most interesting are their results on copolymers ccmtaining low concentrations of chromophore (for which heat effects are less important), namely copolymers of )8-hydroxyethyl methacrylate (0.99) and azonaphthol methacrylate (XII) (0.01) swollen in water... [Pg.38]

Plastics that are commonly processed by extrusion include acrylics (polymethacrylates, polyacrylates) and copolymers of acrylonitrile cellulosics (cellulose acetate, propionate, and acetate butyrate) polyethylene (low and high density) polypropylene polystyrene vinyl plastics polycarbonates and nylons. The material properties and extrusion properties have been reviewed by Whelan and Dunning.Additives that may be included to modify or enhance proper-ties include lubricants and antislip agents to assist processing during extrusion plasticizers to achieve softness and flexibility stabilizers and antioxidants to retard or prevent degradation and dyes and pigments. [Pg.1720]

Homopolymers or copolymers each unit of which is ionizable examples of this type being polyacrylic acid or copolymers of acrylic acid with styrene sulfonic acid. Here again partial or complete ionization is possible. [Pg.61]

Polymethacrylic and polyacrylic acids give essentially no carbon dioxide under these conditions, while polymaleic acid (3ff) evolves 0.2 moles/monomer unit. Copolymers of itaconic and acrylic acid decarboxylate to produce an amount of carbon dioxide roughly corresponding. [Pg.227]

The pyrolysate of polyacrylic-/nfer-nef-polysiloxane copolymer contains as main fragment molecules pyrolysis products similar to those of poly(butyl acrylate) and of poly(dimethylsiloxane (see Figure 6.7.8. and Section 16.1). The identification of fragments that would indicate sequences of other comonomers or any molecular connections between the two types of comonomer units was not possible. Other copolymers with acrylic acid as comonomer were studied using analytical pyrolysis. Among these are copolymers with special properties such as the copolymer with the formula shown below ... [Pg.362]


See other pages where Copolymers of polyacrylates is mentioned: [Pg.96]    [Pg.218]    [Pg.3385]    [Pg.93]    [Pg.96]    [Pg.218]    [Pg.3385]    [Pg.93]    [Pg.350]    [Pg.176]    [Pg.455]    [Pg.99]    [Pg.37]    [Pg.99]    [Pg.454]    [Pg.520]    [Pg.132]    [Pg.167]    [Pg.146]    [Pg.74]    [Pg.191]    [Pg.144]    [Pg.98]    [Pg.78]    [Pg.167]    [Pg.485]    [Pg.177]    [Pg.857]    [Pg.1292]    [Pg.553]    [Pg.558]   
See also in sourсe #XX -- [ Pg.216 , Pg.217 , Pg.218 , Pg.219 , Pg.220 ]




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