Vinyl acetate copolymers with

The low vinyl acetate ethylene—vinyl acetate copolymers, ie, those containing 10—40 wt % vinyl acetate, are made by processes similar to those used to make low density polyethylene for which pressures are usually > 103 MPa (15,000 psi). A medium, ie, 45 wt % vinyl acetate copolymer with mbber-like properties is made by solution polymerisation in /-butyl alcohol at 34.5 MPa (5000 psi). The 70—95 wt % vinyl acetate emulsion copolymers are made in emulsion processes under ethylene pressures of 2.07—10.4 MPa (300—1500 psi). 

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). 

A different approach, although stdl working with essentially non-fiinctional polymers has been exemplified [114,115], in which, a 100% solid (solvent free) hot melt has been irradiated to produce pressure-sensitive adhesives with substantially improved adhesive properties. Acrylic polymers, vinyl acetate copolymers with small amounts of A,A -dimethylaminoethyl methacrylate, diacetone acrylamide, A-vinyl pyrrohdone (NVP) or A A have been used in this study. Polyfunctional acrylates, such as trimethylolpropane trimethacrylate (TMPTMA) and thermal stabilizers can also be used. 

Partially saponified poly(vinyl acetate) Fully saponified poly(vinyl acetate) Copolymers with crotonic acid Copolymers with vinyl acetate with methacrylic acid with acrylic acid esters with acrylonitrile with styrene with ethyl vinyl ether with butadiene... 

Rhodium precipitation in solubilized rhodium-phosphite complex catalyzed liquid recycle hydroformylation may be minimized or prevented by carrying out product recovery in the presence of an organic polymer containing polar functional groups such as amides, ketones, carbamates, ureas and carbonates.[20] Patent examples include the use of polyvinylpyrrolidone and vinylpyrrolidone-vinyl acetate copolymer with diorganophosphite-modified rhodium catalysts. 

Can produce ethylene and vinyl acetate copolymer with long chain branching Currently a limited range of comonomers, mainly linear polymer chains with short chain branching... 

Table V. Grafting of Vinyl Chloride on Ethylene—Vinyl Acetate Copolymers with Non-uniform Molecular Weight (50% VAC in the Backbone)...

Instruction C. Product 14. In a stirrer autoclave, 1300 grams of vinyl chloride and 700 grams of an ethylene-vinyl acetate copolymer with 17% vinyl acetate are stirred at 75°C. and then cooled to 40°C. Two grams of azodiisobutyronitrile dissolved in 30-40 ml. of vinyl chloride are introduced under pressure, the solution is stirred at 40 °C. for one... 

Dincer, S. Bonner, D. C., "Thermodynamic Analysis of an Ethylene and Vinyl Acetate Copolymer with Various Solvents by Gas Chromatography," Macromolecules, 11,107 (1978). 

Walsh, D. J. Higgins, J. S. Rostami, S. Weeraperuma, K., "Compatibility of Ethylene-Vinyl Acetate Copolymers with Chlorinated Polyethylenes. 2. Investigation of the Thermodynamic Parameters," Macromolecules, 16, 391 (1983). 

Fig. 5. Plots of A, transmitted light intensity and B scattered light intensity (arbitrary units) against temperature for an initially homogeneous blend of an ethylene vinyl acetate copolymer with a chlorinated polyethylene. At the phase separation temperature there is a drop in transmitted intensity and a rise in scattered intensity...

This is responsible for the miscibility of various polyesters polyacrylates and vinyl acetate copolymers with PVC Another postulated interaction which has not been studied so much is that between ether groups and aromatic rings which may be responsible for the miscibility of polystyrene and poly(methyl vinyl ether). Interactions probably also exist between other groups and aromatic moeties. However, some interactions can at present only be inferred from favourable heats of mixing found for low molecular weight analogues without much being really understood at a molecular level. 

Fig. 31. Experimental cloud point curve (dotted line) and simulated spinodals, for blends of an ethylene-vinyl acetate copolymer with chlorinated polyethylene. The initial curve (A) using an X,j (—4.2 Jcm ) value calculated from heat of mixing data and an adjusted (—0.0108 J cm K" ) was too flat bottomed. By adjusting (and the appropriate Q,j) a closer fit could be obtained (B) Q,j = -0.00678 (C)...

A crosslinked polymer synthesised [50] by crosslinking ethylene-vinyl acetate copolymer with dicumyl peroxide gave two large signal at 31.8 and... 

I. Organic carbochain polymers and copolymers of poly-4-methylpentene-l [4] PMMA or methyl methacrylate (MMA) copolymers with other alkyl-(meth)acrylates (AMA) [1-3, 5] poly(vinyl acetate) vinyl acetate copolymer with ethylene [4, 6-8] polymers of chlorine-containing olefins [9]. 

Poly(vinyl acetate) and vinyl acetate copolymers with crotonic acid, vinyl laurate, and dibutyl maleate are important solid resins some are available in solution. 

Near-infrared diffuse reflectance spectra were measured by use of a rotating drawer for pellets of 12 kinds of ethylene-vinyl acetate copolymers with vinyl acetate comonomer varying in the 7-44 wt% range. An attempt was made to predict the melting points of these copolymers. The potential of near-infrared spectroscopy with that of Raman spectroscopy in the discrimination of copolymers and the prediction of their properties was given. 23 refs. 

Specific interactions in binary blends of ethylene-vinyl acetate copolymer with various low molecular weight terpene-phenol tackifying resins (TPR) were systematically investigated, as a function of the composition of the blend and of the electron acceptor ability of the resin, by using attenuated total reflection FTIR spectroscopy. Molecular acid-base were evidenced between TPR hydroxyl groups and EVA carbonyl groups. Quantitative information on the fraction of acid-base bonded entities, the enthalpy and equilibrium constant of pair formation were obtained. A crystalline transition of the EVA copolymer was observed and discussed in terms of enthalpy and entropy considerations based on FTIR and calorimetric DSC investigations. Fundamental results are then summarised to predict the interfacial reactivity of such polymer blends towards acid or basic substrates. 16 refs. 

Adhesives for paper-to-paper applications are made from polyvinyl acetate emulsions, with added plasticizers, or from vinyl acetate copolymers (notably Ethylene-vinyl acetate copolymers) with added polyvinyl alcohol to modify viscosity, flow and coating properties, remoistenability and the rate of formation of the adhesive bond. These... 

Ethylene-vinyl alcohol copolymer (EVAL, E/ VAL, and EVOH) n. A family of copolymers made by hydrolyzing ethylene-vinyl acetate copolymers with high VA content. Those containing about 20-35% ethylene are useful as barriers to many vapors and gases, though not to water. Because of their water sensitivity, they are usually sandwiched between layers of other polymers. 

The foUowing activity coefficients and interaction parameters determined by GLC for solute-statistical copolymers may be found in the literature (a) forty three non-polar and polar solutes on ethylene-vinyl acetate copolymer with 29% weight of vinyl acetate at 150.6 and 160.5°C [105] chloroform, carbon tetrachloride, butyl alcohol, butyl chloride, cyclohexanol, cyclohexane, phenol, chlorobenzene and pentanone-2 on the same copolymer with 18% weight vinyl acetate at 135°0 [102], normal xdkanes (C5, Oj, Og, Ojo), oct-l-ene, chlorinated derivatives, n-butanol, toluene, benzene, methyl-propyl-ketone and n-butyl-cyclohexane on the copolymer mentioned with 40% weight vinyl acetate at 65, 75 and 85°0 [68, 106] (b) n-nonane, benzene, chloroform, methyl-ethyl-ketone and ethanol in methyl methacrylate-butyl methacrylate copolymer with 10% butyl methacrylate [32] (c) hydrocarbons in styrene-alkyl methacrylates copolymers at 140°C [101] (d) the solutes in (b) on butadiene-acrylonitrile copolymer with 34% weight acrylonitrile [68]. 

As mentioned previously, the Alfrey Priee Q and e values for vinyl acetate are 0.026 and —0.22, respectively [226]. Thus vinyl acetate is rather sluggish in its free-radical copolymerization, with most monomers, particularly olefinic monomers, bearing electron-donating subtitutents. The copolymerization reactivity ratios reflect the reluctance of vinyl acetate to enter into copolymerization with other monomers [270]. Nevertheless, vinyl acetate copolymers with a great many electron-rich as well as electron-poor olefins have been prepared. Especially significant from a commercial point of view are copolymers with ethylene, vinyl chloride, acrylates, methacrylates, fumarates, and maleates. Often, mixtures of three and more comonomers are used in these copolymerizations. 

D1N Dincer, S. and Botmer, D.C., Thermodynamic analysis of ethylene and vinyl acetate copolymer with various solvents by gas chromatography, Macroffro/ecw/ra, 11, 107, 1978. 

WAL Walsh, D.J., Higgins, J.S., Rostami, S., and Weeraperama, K., Compatibility of ethylene-vinyl acetate copolymers with chlorinated polyethylenes. 2. Investigation of the thermodynamic parameters, Macroffro/ecw/ra, 16,391, 1983. 

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