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Compatability: acrylics

Uses Acrylic in combination with compat. acrylic resins to improve applic. [Pg.503]

Unlike most crystalline polymers, PVDF exhibits thermodynamic compatibiUty with other polymers (133). Blends of PVDF and poly(methyl methacrylate) (PMMA) are compatible over a wide range of blend composition (134,135). SoHd-state nmr studies showed that isotactic PMMA is more miscible with PVDF than atactic and syndiotactic PMMA (136). MiscibiUty of PVDF and poly(alkyl acrylates) depends on a specific interaction between PVDF and oxygen within the acrylate and the effect of this interaction is diminished as the hydrocarbon content of the ester is increased (137). Strong dipolar interactions are important to achieve miscibility with poly(vinyhdene fluoride) (138). PVDF blends are the object of many papers and patents specific blends of PVDF and acryflc copolymers have seen large commercial use. [Pg.387]

Poly(ethyl methacrylate) (PEMA) yields truly compatible blends with poly(vinyl acetate) up to 20% PEMA concentration (133). Synergistic improvement in material properties was observed. Poly(ethylene oxide) forms compatible homogeneous blends with poly(vinyl acetate) (134). The T of the blends and the crystaUizabiUty of the PEO depend on the composition. The miscibility window of poly(vinyl acetate) and its copolymers with alkyl acrylates can be broadened through the incorporation of acryUc acid as a third component (135). A description of compatible and incompatible blends of poly(vinyl acetate) and other copolymers has been compiled (136). Blends of poly(vinyl acetate) copolymers with urethanes can provide improved heat resistance to the product providing reduced creep rates in adhesives used for vinyl laminating (137). [Pg.467]

The anthraquinones are useful in acrylics and are compatible with polystyrene and ceUulosics. Solvent Red 111 has a special affinity for poly(methyl methacrylate) as the red in automobile taillights exposure for a year in Florida or Arizona produces only a very slight darkening. Acid types are usehil for phenohcs (see Dyes, anthraquinone). [Pg.464]

In addition to acting as impact modifiers a number of polymeric additives may be considered as processing aids. These have similar chemical constitutions to the impact modifiers and include ABS, MBS, chlorinated polyethylene, acrylate-methacrylate copolymers and EVA-PVC grafts. Such materials are more compatible with the PVC and are primarily included to ensure more uniform flow and hence improve surface finish. They may also increase gelation rates. In the case of the compatible MBS polymers they have the special function already mentioned of balancing the refractive indices of the continuous and disperse phases of impact-modified compound. [Pg.342]

Rosin and its derivates have shown wide compatibility with a broad range of acrylics and other PSA polymer precursors. This property has made them one of the most common tackifiers in the industry. [Pg.504]

The other class of acrylic compatible tackifiers includes those based on ter-penes. Terpenes are monomers obtained by wood extraction or directly from pine tree sap. To make the polyterpene tackifiers, the monomers have to be polymerized under cationic conditions, typically with Lewis acid catalysis. To adjust properties such as solubility parameter and softening point, other materials such as styrene, phenol, limonene (derived from citrus peels), and others may be copolymerized with the terpenes. [Pg.504]

There are several ways in which the impact properties of plastics can be improved if the material selected does not have sufficient impact strength. One method is by altering the composition of the material so that it is no longer a glassy plastic at the operating temperature of the product (Chapter 6). In the case of PVC this is done by the addition of an impact modifier which can be a compatible plastic such as an acrylic or a nitrile rubber. The addition of such a material lowers the glass transition temperature and the material becomes a rubbery viscoelastic plastic with much improved impact properties. This is one of the methods in which PVC materials are made to exhibit superior impact properties. [Pg.92]

Radical cyclization is compatible with the presence of other functional groups. Treatment of XCH2CON(R)-C(R )=CH2 derivatives (X = Cl, Br, 1) with Ph3SnH and AIBN led to formation of a lactam via radical cyclization. " Cyclization of N-iodoethyl-5-vinyl-2-pyrrolidinone led to the corresponding bicyclic lactam, " and there are other examples of radical cyclization with molecules containing a lactam unit " or an amide unit. Radical cyclization occurs with enamines as well. Photochemical irradiation of A,A-dialIyl acrylamide leads to formation of a lactam ring, and in this case thiophenol was added to generate the phenylthio derivative. Phenylseleno N-allylamines lead to cyclic amines. co-Iodo acrylate esters cyclize to form lactones. " ... [Pg.1040]

Brauer, G. M., Stansbury, J. W. Argentar, H. (1983). Development of high-strength, acrylic resin-compatible adhesive cements. Journal of Dental Research, 62, 366-70. [Pg.353]

The protic catalytic conditions are also compatible with trapping of the radicals formed after cyclization with acrylates or acrylonitriles prior to their reduction with Cp2TiCl . In this manner highly substituted alkenes for the potential preparation of modified steroids can be accessed (Scheme 19) [97]. [Pg.50]

Although the metathesis of ene-ynes is a valuable method for the preparation of 1,3-butadienes, and may be used for Diels-Alder reactions, a problem arises from the need to employ either a high temperature or a Lewis add to accelerate the cycloaddition, which is usually not feasible with the Grubbs catalyst Therefore, the combination of metathesis and cycloaddition is usually performed in sequential fashion (as just shown, and highlighted earlier) [264]. However, Laschat and coworkers [265] have shown the Lewis acid BC13 to be compatible with the Grubbs I catalyst (6/3-13). Reaction of 6/3-92 and ethyl acrylate using a mixture of 2.5 equiv. of the Lewis acid and 10 mol% of 6/3-13 led to 6/3-93 in 60% yield (Scheme 6/3.27). [Pg.454]

Transparency is often required. This is achieved by arranging that the particle size of the modifier to be below that of the wavelength of visible light (0.4-0.8 pm). This can normally be achieved by emulsion polymerisation, e.g., polybutadiene, polystyrene. Adhesion and surface compatibility between the polymer and modifier can be achieved by surface grafting of polar groups, e.g., acrylonitrile, various acrylates, onto the impact modifier surface before blending. [Pg.114]

Much work on the preparation of nonaqueous polymer dispersions has involved the radical polymerization of acrylic monomers in the presence of copolymers having the A block the same as the acrylic polymer in the particle core 2). The preparation of polymer dispersions other than polystyrene in the presence of a PS-PDMS diblock copolymer is of interest because effective anchoring of the copolymer may be influenced by the degree of compatibility between the PS anchor block and the polymer molecules in the particle core. The present paper describes the interpretation of experimental studies performed with the aim of determining the mode of anchoring of PS blocks to polystyrene, poly(methyl methacrylate), and poly(vinyl acetate) (PVA) particles. [Pg.268]

Nishiguchi MK, Somero GN (1992) Temperature- and concentration-dependence of compatibility ofthe organic osmolyte P-dimethylsulfoniopropionate. Cryobiology 29 118-124 Noordkamp D, Gieskes W, Gottschal J, Forney L, van Rijssel M (2000) Acrylate in Phaeocystis colonies does not affect surrounding bacteria. J Sea Res 43 287-296 Otte ML, Morris JT (1994) Dimethylsulphoniopropionate (DMSP) in Spartina altemiflora Loisel. Aquat Bot 48 239-259... [Pg.192]

PVA and PAcr.Ac. are compatible polymers on the whole range of composition [40-45], These blends are homogeneous and the films are transparent evidencing a good clarity [43,57] or semitransparency [43], However a heterogeneous IPN [45] was obtained by acrylic acid polymerization in a PVA matrix. [Pg.129]

After cleaning by abrasion and with solvents, the polyimides can be stuck with a poly-imide, epoxy or acrylic resin adhesive whose thermal resistance is compatible with the operating conditions. Preliminary tests are essential. [Pg.598]

An interesting feature of current commercial products is that the polymer vehicles available for formulation have been limited to nonionic and anionic materials. The delivery vehicles available included off-the-shelf polymers such as carboxymethylcellulose, soluble starch, hydroxyethyl-cellulose, polyvinyl alcohol, poly(acrylic acid), and polyvinylpyrrolidone, or mixtures thereof. The choice of available polymeric delivery system primarily depends on component compatibility, aesthetics, and efficacy. However, by reliance upon available (off-the-shelf) systems, limitations on bioadhesion, drug bioavailability, contraceptive efficacy, and end-use characteristics has been limited. [Pg.217]


See other pages where Compatability: acrylics is mentioned: [Pg.17]    [Pg.20]    [Pg.218]    [Pg.17]    [Pg.20]    [Pg.218]    [Pg.134]    [Pg.389]    [Pg.335]    [Pg.717]    [Pg.734]    [Pg.408]    [Pg.221]    [Pg.31]    [Pg.243]    [Pg.869]    [Pg.873]    [Pg.141]    [Pg.344]    [Pg.225]    [Pg.226]    [Pg.237]    [Pg.108]    [Pg.283]    [Pg.364]    [Pg.22]    [Pg.50]    [Pg.124]    [Pg.53]    [Pg.221]    [Pg.70]    [Pg.71]    [Pg.276]    [Pg.269]    [Pg.204]   
See also in sourсe #XX -- [ Pg.148 ]




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