Poly-vinylacetate

Poly vinylacetate has found use as a binder in expls (Refs 2, 3 and 6)... 

Maleimides Alkyl and aryl maleimides in small concentrations, e.g., 5-10 wt% significantly enhance yield of cross-link for y-irradiated (in vacuo) NR, cw-l,4-polyisoprene, poly(styrene-co-butadiene) rubber, and polychloroprene rubber. A-phenyhnaleimide and m-phenylene dimaleimide have been found to be most effective. The solubihty of the maleimides in the polymer matrix, reactivity of the double bond and the influence of substituent groups also affect the cross-fink promoting ability of these promoters [82]. The mechanism for the cross-link promotion of maleimides is considered to be the copolymerization of the rubber via its unsaturations with the maleimide molecules initiated by radicals and, in particular, by allyfic radicals produced during the radiolysis of the elastomer. Maleimides have also been found to increase the rate of cross-linking in saturated polymers like PE and poly vinylacetate [33]. 

Robeson LM, Kuphal JA (1989) Blends of poly(vinylacetate) and poly(propylene carbonate). US Patent 4,912,149... 

Abbreviations. BZC, benzalkonium chloride PS, potassium sorbate CDs, cyclodextrins HP-fS-CD, 2-hydroxypropyl-p-cyclodextrin HPMCAS, hydroxypropyl methylcellulose acetate succinate PEG, polyethylene glycol P-407, poloxamer 407 PVAP, poly vinylacetate phthalate. 

CA 68, 41780b(1968) [Thickeners (such as homopolymers and copolymers of unsatd acids, ketones acetals) for liquid expls (such as NG) are discussed. For example, lOg of a 40% soln of poly(vinylacetate) in EtOAc was mixed with 90g NG and after evapn of EtOAc on a water baih, a clear, homogeneous viscous soln was formed. Condensation products of aldehydes and ketones and of diols and... 

Poly vinylacetate 6,1 kcal/gmol Polymethyl methacrylate 7,2 kcal/gmol Hydrogen (potential) bonds AU = 6—20 kcal/gmol... 

Figure 10. Density of different polymer latex particles as a function of centrifugation time (N = 40.000 min 1) (Y ) polyvinyl acetate (%) poly(vinylacetate-co-ethylene) (A) polystyrene (X) poly( butadiene-co-styrene) (O) poly butadiene)...

The dilatational rheology of the poly(vinylacetate) monolayer onto an aqueous subphase has been studied between 1°C and 25°C by Monroy et al. [59], These authors have used the combination of several techniques. By this way, the exploration of a broad frequency range was possible. The relaxation experiments have shown multiexponential decay curves, whose complexity increases with decreasing the temperature. A regularization technique has been used to obtain the relaxation spectra from the relaxation curves and the dilatational viscoelastic parameters have been calculated from the spectra. The shapes of the relaxation spectra agree with the predictions of the theoretical model proposed by Noskov [100],... 

Gelva Poly(VinylAcetate) Technical Bulletin, Publication No. 6103, Monanto Chemical Co., St. Louis, Mo., 1969. 

We have studied the addition of methylmetacrylate monomer to macroradicals of polystyrene and poly vinylacetate. 

Grafting of Monomer to Surface-Active Agents. A recent patent claims the preparation of a F/T stable poly(vinylacetate-vinylbenzoate) copolymer emulsion in the presence of a graft polymer of vinylacetate on a polyalkylene glycol (21). 

We believe that the shell acts as a physical barrier preventing contact of propargite with the leaf thus, the presence of a shell reduces phytotoxlclty. Because the shell is porous and inconplete, the poly vinylacetate shell does not prevent the... 

Fig. 8.16 Conductivity of a composite formed from carbon-black coated poly(vinylacetate) pellets (Grunlan et al., 2001). Reprinted by permission of John Wiley Sons, Inc.

It has been attempted to perform template polymer syntheses without using biological sources. Concepts focus on the formation of a complex between monomer molecules and a present macromolecule [4,480], This way the monomer will get preorganized and the polymerization is supposed to follow a zip mechanism controlled by the length and the configuration of the template polymer, offering replication of the molecular weight and control of the stereo structure. Polymerization of acrylic acid in the presence of poly(ethyleneimine), N-vinylimidazole/ poly(methacrylic acid) or acrylonitrile with poly(vinylacetate) have been described [469,470,471,472,473]. Recently the preparation of solid polyelectrolyte complexes from chitosan and sodium-styrenesulfonate has been reported [481]. 

Improved rubbing fastness can be achieved with partially hydrolysed poly vinylacetate (PVAc/PVA) or polyvinylether and the application of pigment binders, mostly based on acrylic copolymers similar to those nsed as hand builders (Chapter 4). Application methods mostly nse pad-dry techniqnes. 

Poly vinylacetate aq emulsion for use as a binder in non-metallic cartridge cases is covered by US Mil Spec, Polyvinyl Acetate Aqueous Emulsion (PAAE) (For use in Ammunition) , MiL-P-50S55( V U) (31 March 1971). The requirements and criteria are in Table 1... 

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