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Showing papers on "Vinyl acetate published in 1977"


Patent
Takeru Higuchi1, Anwar Hussain1
21 Sep 1977
TL;DR: A drug delivery device for a continuous and controlled rate for a prolonged period of time is comprised of a shaped body of polymeric material containing a pharmaceutically acceptable drug and permeable to passage of the drug by diffusion.
Abstract: Drug-delivery device for releasing a drug at a continuous and controlled rate for a prolonged period of time is comprised of a shaped body of polymeric material containing a pharmaceutically acceptable drug and permeable to passage of the drug by diffusion. The polymeric material is an ethylene-vinyl acetate copolymer having a vinyl acetate content of about 4 to 80% by weight and a melt index of about 0.1 to 1000 grams per 10 minutes.

228 citations


Book ChapterDOI
01 Jan 1977
Abstract: III. Polyaddition . . . . . . . . . . . . . . . . . . . . 56 A. Polymerization through the Ring . . . . . . . . . . . . 57 1. Furan and 2-Alkylfurans . . . . . . . . . . . . . . 57 a) Free-Radical Systems . . . . . . . . . . . . . 57 b) Anionic Systems . . . . . . . . . . . . . . . . 57 c) Cationic Systems . . . . . . . . . . . . . . . . 58 d) ~'-Ray Irradiation . . . . . . . . . . . . . . . 61 e) Stereospecific Systems . . . . . . . . . . . . . . 61 2. Copolymerization of Furan and Homologues with Maleic Anhydride . . . . . . . . . . . . . . . . . . . 62 3. Benzofuran and Naphthofurans . . . . . . . . . . . . 63 4. Dihydrofurans . . . . . . . . . . . . . . . . . 65 5. The Photopolymerization of 2-Furaldehyde . . . . . . . . 66 6. Miscellaneous Reactions . . . . . . . . . . . . . . 68 a) The Paterno-Btichi Reaction with Furans . . . . . . . . 68 b) The Aromatization of bis-Furan Adducts . . . . . . . . 68 c) Poly(2,5-difurylketone) . . . . . . . . . . . . . 68 B. Polymerization through a Funct ion External to the Ring . . . . 69 1. 2-Alkenylfurans . . . . . . . . . . . . . . . . . 69 a) Free-Radical Systems . . . . . . . . . . . . . . 69 b) Anionic Systems . . . . . . . . . . . . . . . . 71

105 citations



Patent
25 May 1977
TL;DR: In this paper, the authors described a set of dry pigment compositions which are easily dispersed in aqueous systems, and the compositions contain 55 to 80% of a pigment and 45 to 20% of nonionic material comprising, by weight of the pigment, 15 to 45% of the nonionic dispersing agent and 10 to about 67% of water-dispersible, at least partially hydrolyzed polymer of vinyl acetate or a polymer of an N-vinyl pyrrolidone.
Abstract: Dry pigment compositions which are easily dispersed in aqueous systems are described. The compositions contain 55 to 80% of a pigment and 45 to 20% of a nonionic material comprising, by weight of the pigment, 15 to 45% of a nonionic dispersing agent and 10 to about 67% of a water-dispersible, at least partially hydrolyzed polymer of vinyl acetate or a polymer of an N-vinyl pyrrolidone.

52 citations


Patent
08 Feb 1977
TL;DR: Perfumed composites of ethylene and polar monomer copolymers, such as vinyl acetate and ethyl acrylate, are disclosed as discussed by the authors, which faithfully retain the fragrance of the perfume oil for periods up to a year and more.
Abstract: Perfumed composites of ethylene and polar monomer copolymers, such as vinyl acetate and ethyl acrylate, are disclosed Shaped bodies prepared from such composites faithfully retain the fragrance of the perfume oil for periods up to a year and more

49 citations


Patent
30 Jun 1977
TL;DR: In this article, a hydrolyzed terpolymer of maleic anhydride with vinyl acetate and ethyl acrylate was used for the prevention of scale and the inhibition of corrosion.
Abstract: A process for the prevention of scale and the inhibition of corrosion which comprises adding to water a hydrolyzed terpolymer of maleic anhydride with vinyl acetate and ethyl acrylate, the molar ratio of maleic anhydride to the other monomers being from 2.5:1 to 5:1, the ratio of vinyl acetate to ethyl acrylate being 1:1 to 2:1, and the molecular weight of the terpolymer being below 1000.

44 citations


Book ChapterDOI
01 Jan 1977

37 citations


Journal ArticleDOI
TL;DR: In this paper, the molecular weights obtained at high conversions agreed more closely with predictions based upon a locally segregated state than with those based on complete molecular mixing, however, calculations based on agitation and diffusion rates raised serious questions about the validity of the segregation model for this polymerization.

37 citations


Journal ArticleDOI
TL;DR: In this article, the authors used thermally stimulated current (TSC) to study the low-temperature dielectric β relaxations of several polymers including poly(vinyl chloride), polyvinyl acetate, polyamide 6, 6,6, poly(t-butyl acrylate), poly(methyl methacrylate) and poly(ethyl methacricrylate).
Abstract: The method of thermally stimulated current (TSC) has been used to study the low-temperature dielectric β relaxations of several polymers including especially poly(vinyl chloride), poly(vinyl acetate), polyamide 6, 6,6,poly(t-butyl acrylate), poly(methyl methacrylate), poly(ethyl methacrylate), poly(phenyl methacrylate), and poly(t-butyl methacrylate). The distribution characteristics of the relaxation processes have been determined from the corresponding TSC peaks by a fractional polarization technique which consists of applying the electric field in several discrete steps during a slow cooling. Several common features have been found in all the polymers investigated: the β peaks are characterized by a distribution of relaxation times resulting from a distribution in activation energy and this distribution is quasisymmetrical and continuous. These facts are in agreement with the hypothesis of a relaxation involving local motions of small polar groups undergoing various interactions with the environment. Some discrepancy remains, however, between our calculated values of the mean activation energy and those obtained from the dielectric loss.

35 citations


Journal ArticleDOI
TL;DR: In this paper, it was shown that poly(vinyl chloride is not miscible with poly(VCL) due to a specific interaction of the ketone carbonyl of the terpolymer (proton acceptor) and the tertiary hydrogen of poly(vyl chloride), and this specific interaction allows for a broad range of terpolymers compositions which retain miscibility with polyVCL.
Abstract: Ethylene/ethyl acrylate/carbon monoxide ter polymers (E/ EA/CO) can exhibit a very high degree of miscibility with poly(vinyl chloride) as determined from dynamic mechanical measurements. The blends yield transparent films and show a large amorphous phase which exhibits only one major glass transition. However, some crystallinity can be detected and has been measured by differential, scanning calorimetry. Residual crystallinity is at least partially due to the somewhat non-uniform nature of the terpolymerization. The acrylate monomer exhibits faster polymerization rates than the other two constituents. By contrast, ethylene/ethyl acrylat copolymers are not miscible with poly(vinyl chloride). The addition of carbon monoxide to the termpolymer structure is believed to yield miscibility with poly(vinyl chloride) via specific interaction of the ketone carbonyl of the terpolymer (proton acceptor) and the tertiary hydrogen of poly(vinyl chloride) (proton donor). This specific interaction allows for a broad range of terpolymer compositions which retain miscibility with polyvinyl chloride. Similar results are also observed with ethylene/vinyl acetate/carbon monoxide (E/VA/CO) as well as ethylene/2-ethylhexyl acrylate/carbon monoxide termpojymers. The vinyl acetate terpolymers (and their blends) display a lower degree of crystallinity than the E/EA/ CO. This is consistent with the more uniform nature of the E/VAJCO terpolymerization.

32 citations


Journal ArticleDOI
01 Mar 1977-Polymer
TL;DR: Proton spin and Overhauser enhancements in vinyl polymers have been calculated for three correlation time distributions, and compared with experimental measurements on solutions of poly(vinyl acetate) in toluene- d 8 as discussed by the authors.

Patent
12 Sep 1977
TL;DR: A termonomer mixture of ethylene, vinyl acetate and not more than 5 weight percent carbon monoxide is copolymerized to provide a resin of desirable rheological properties e.g. low Melt Flow Rate and a high melt viscosity, when prepared at temperatures not exceeding about 260° F.
Abstract: A termonomer mixture of ethylene, vinyl acetate and not more than about 5 weight percent carbon monoxide is copolymerized to provide a resin of desirable rheological properties e.g. low Melt Flow Rate and a high melt viscosity, when prepared at temperatures not exceeding about 260° F.

Patent
05 Jul 1977
TL;DR: In this article, a composition containing interpolymerized vinyl chloride, vinyl acetate and vinyl alcohol; a copolymer of ethylene and vinyl acetates and a castor oil-modified sebacic alkyd is interposed between a vinyl skin and the printing on the surface of a vinyl core.
Abstract: A laminated article in which a composition containing interpolymerized vinyl chloride, vinyl acetate and vinyl alcohol; a copolymer of ethylene and vinyl acetate and a castor oil-modified sebacic alkyd is interposed between a vinyl skin and the printing on the surface of a vinyl core. An adhesive composition is also claimed.

Patent
07 Jan 1977
TL;DR: In this article, a photosensitive material for use in electrophotography which comprises a conductive support having a photoconductive layer coated with a protective layer, the material being superior in light-decay property, mechanical strength and image formability, wherein said protective layer is composed of either (1) a member selected from the group of resins consisting of polyvinyl butyral, polyvyl acetate, acryl or derivative resins thereof, copolymers of styrene and maleic anhydride or alkyl esters thereof,
Abstract: The present invention provides a photosensitive material for use in electrophotography which comprises a conductive support having a photoconductive layer coated with a protective layer, the material being superior in light-decay property, mechanical strength and image formability, wherein said protective layer is composed of either (1) a member selected from the group of resins consisting of polyvinyl butyral, polyvinyl acetate, acryl or derivative resins thereof, copolymers of styrene and maleic anhydride or alkyl esters thereof, copolymers of vinyl acetate or derivatives thereof and vinyl pyrrolidone, copolymers of butyl vinyl ether and maleic anhydride or alkyl monoesters thereof and shellac, or of (2) a resin and silane-coupling agent.

Patent
20 Apr 1977
TL;DR: A pressure-sensitive adhesive containing a base material consisting of an aqueous emulsion of vinyl acetate-ethylene copolymer having an ethylene content of 15 to 40% by weight, with an intrinsic viscosity of 0.4 to 1.4 dl/g as mentioned in this paper.
Abstract: A pressure-sensitive adhesive containing a base material therefore comprising an aqueous emulsion of vinyl acetate-ethylene copolymer having an ethylene content of 15 to 40% by weight, preferably 20 to 35% by weight, the benzene-insoluble part of less than 30% by weight, preferably less than 20% by weight, and an intrinsic viscosity of the benzene-soluble part of 0.4 to 1.4 dl/g, preferably 0.6 to 1.0 dl/g, (at 30° C) which is prepared by the emulsion copolymerization of vinyl acetate and ethylene and optionally at least one unsaturated monovinyl monomer in the presence of a protective colloid and a polyoxyethylenic nonionic sulfactant, or a base material comprising a blend of said aqueous emulsion of vinyl acetate-ethylene copolymer as set forth above and an emulsion of an acrylic ester copolymer; and the aqueous emulsion of vinyl acetate-ethylene copolymer useful as the base material for the pressure-sensitive adhesive.


Patent
05 May 1977
TL;DR: In this article, gun roving glass fibers are coated with an aqueous-based size comprising an epoxidized polyvinyl acetate copolymer in combination with a vinyl acetate-ethylene copolymers.
Abstract: Disclosed are gun roving glass fibers coated with an aqueous-based size comprising an epoxidized polyvinyl acetate copolymer in combination with a vinyl acetate-ethylene copolymer and a vinyl acetate copolymer.

Patent
27 Dec 1977
TL;DR: In this article, a composite fiber having side-by-side or sheath and core arrangement of the first component consisting mainly of crystalline polypropylene or propylene copolymer mainly of propylene and the second component consisting of an ethylene-vinyl acetate copolymers having a vinyl acetate content of 0.5-18 mol % of the total monomers, a saponification product thereof or (3) a mixed polymer of any of the foregoing members (1) and polyethylene having the total content of Vinyl acetate and vinyl alcohol
Abstract: Tobacco filters having uniform hardness and small pressure drop which give uniform flow of smoke can be obtained by forming bundles of fibers consisting of 20-100% by weight of composite fibers based upon the total amount of mixed fibers of said composite fibers and 80-0% of other fibers, subjecting said composite fibers to heat treatment at a temperature lower than the melting point of the first component and higher than the melting point of the second component and stabilizing said fiber bundles by the self adhesion of the second component, said composite fibers having side-by-side or sheath and core arrangement of the first component consisting mainly of crystalline polypropylene or propylene copolymer mainly of propylene and the second component consisting of (1) an ethylene-vinyl acetate copolymer having a vinyl acetate content of 0.5-18 mol % of the total monomers, (2) a saponification product thereof or (3) a mixed polymer of any of the foregoing members (1) and (2) and polyethylene having the total content of vinyl acetate and vinyl alcohol component of 0.5 mol % or more based upon the total monomer content of the mixed polymer; said second component having a circumferential ratio of 60- 100% of the fiber cross-section.

Patent
19 Dec 1977
TL;DR: In this paper, the starting polymers are preferably copolymers of ethylene and vinyl acetate having stiffness less than about 20,000 psi, and mixed blowing agents are particularly characterized as mixtures of dichlorodifluoromethane and at least one fluorocarbon constituent A, as defined.
Abstract: Low density, closed cell, soft foam products having dimensional stability are made from ethylenic resins having low stiffness, especially comprising copolymers consisting essentially of ethylene and monoethylenically unsaturated non-ionic comonomers, by release to lower pressure of a flowable, foamable gel under pressure, e.g., by extrusion foaming, wherein the gel comprises the ethylenic polymer and a volatile mixed blowing agent. The starting polymers are preferably copolymers of ethylene and vinyl acetate having stiffness less than about 20,000 psi. The mixed blowing agents are particularly characterized as mixtures of dichlorodifluoromethane and at least one fluorocarbon constituent A, as defined. Exemplary mixtures contain (I) dichlorodifluoromethane and (II) from 35 to 50 percent chloropentafluoroethane, octafluoropropane or octafluorocyclobutane based on the mixtures of I and II.

Journal ArticleDOI
TL;DR: In this paper, the palladium-catalyzed phenylation of olefins with iodobenzene has been extended to enol esters, in the presence of triethylamine and a catalytic amount of palladium acetate.
Abstract: The palladium-catalyzed phenylation of olefins with iodobenzene has been extended to enol esters. In the presence of triethylamine and a catalytic amount of palladium acetate, vinyl acetate is phenylated with iodobenzene to produce, mainly, stilbene, accopanied by small amounts of (E)- and (Z)-styryl acetates.

Journal ArticleDOI
TL;DR: In this paper, a broad line proton magnetic resonance (NMR) measurements on the system poly(vinyl acetate)-toluene were reported, and four dielectric relaxations were observed between 80 and 400°K.
Abstract: Dielectric measurements, differential thermal analyses (DTA), and broad-line proton magnetic resonance (NMR) measurements are reported on the system poly(vinyl acetate)–toluene. Four dielectric relaxations were observed between 80 and 400°K. From proton NMR measurements on solutions in toluene and in deuterated toluene, the relaxation processes can be assigned, respectively, to segmental motion of poly(vinyl acetate), α; motion of side group, β′ rotation of toluene, β; local motions of poly(vinyl acetate) and toluene, γ, in order of appearance with decreasing temperature. Two stepwise changes in DTA traces have been observed and can be assigned as glass transition points TgI and TgII. Comparison of these glass transition points with temperatures at which dielectric relaxation times for the α and β processes are 100 sec, indicate that segmental motion of poly(vinyl acetate) and rotation of toluene are frozen-in at TgI and TgII, respectively. Activation plots for the α process conform to the Vogel–Tamman equation. In terms of the parameters A, B, and T0 of the equation, TgI can be represented by an expression of the form TgI ≈ T0 + B/(A + 3). In the range of concentration above 50% by weight, A and B are almost independent of concentration but T0 varies strongly. The nature of the secondary dispersions is also discussed.

Patent
Donald Eugene Morris1
14 Oct 1977
TL;DR: Vinyl esters such as vinyl acetate are hydrocarboxylated with tertiary organo-phosphine stabilized palladium catalysts utilizing low water concentration; the ready hydrolysis of the α-acetoxypropionic acid affords a convenient route to lactic acid as discussed by the authors.
Abstract: Vinyl esters such as vinyl acetate are hydrocarboxylated with tertiary organo-phosphine stabilized palladium catalysts utilizing low water concentration; the ready hydrolysis of the α-acetoxypropionic acid affords a convenient route to lactic acid.

Journal ArticleDOI
TL;DR: In this article, a contrast feature was found for the catalytic oxidation of ethyIene by palladium(II) in aqueous and acetic acid solutions, suggesting that the redox-decomposition for the yielding of vinyl acetate is preceded by an equilibrium process between the 2-and 1-acetoxyethylpalladium σ-complexes without any intermolecular hydrogen exchange.

Patent
06 Jun 1977
TL;DR: An improvement in the process of producing polyvinyl chloride by the suspension process in the presence of protective colloids was made by utilizing a protective colloid mixture of from 20% to 80% of the mixture of a polyvyl acetate having a hydrolysis degree of 40 to 55 mol % and the remainder of the protective colloidal mixture of an aminoethyl-hydroxypropyl cellulose having a molar substitution of from 0.05 to 1.5 mols as discussed by the authors.
Abstract: An improvement in the process of producing polyvinyl chloride by the suspension process in the presence of protective colloids by utilizing a protective colloid mixture of from 20% to 80% of the protective colloid mixture of a polyvinyl acetate having a hydrolysis degree of 40 to 55 mol % and the remainder of the protective colloid mixture of (1) a water-soluble polyvinyl alcohol having a hydrolysis degree of 70 to 90 mol %, or (2) an aminoethyl-hydroxypropyl cellulose having a molar substitution of from 0.05 to 1.5 mols of aminoethyl groups and 3 to 5 mols of hydroxypropyl groups, or (3) a vinyl acetate/vinyl pyrrolidone copolymer having a ratio of vinyl pyrrolidone to vinyl acetate in the copolymer of 50% to 70% by weight to 30% to 50% by weight and a K-value of 25 to 40. By the use of this protective colloid mixture, the polyvinyl chloride produced exhibits a large absorption of plasticizer and gives finished products having a low number of specks.

Patent
21 Mar 1977
TL;DR: In this paper, an 82 - 98 weight percent binder is used and various ratios of ethylene to vinyl acetate moieties in the resin are used to modify molding and extrusion properties.
Abstract: Ethylene vinyl acetate copolymer resins are used as desensitizers and bins of moldable explosive compositions of cyclic nitramines, such as RDX. 82 - 98 weight percent binder is used and various ratios of ethylene to vinyl acetate moieties in the resin are used to modify molding and extrusion properties.

Patent
27 May 1977
TL;DR: In this article, a catalytically effective amount of palladium metal on a zinc oxide support in the presence of a sulfur modifier was used to provide mixtures of acetic acid and vinyl acetate.
Abstract: Ethylene and oxygen are reacted in the presence of steam in the vapor phase within the temperature range of from about 150° C. to about 250° C. in contact with a catalytically effective amount of palladium metal on a zinc oxide support in the presence of a sulfur modifier to provide mixtures of acetic acid and vinyl acetate.

Patent
Parker L C1, Kenneth D. Miller1
24 Jan 1977
TL;DR: In this paper, a low-pour fuel composition is prepared by blending with a gas oil a minor amount of a high asphaltene residuum, such as an Arabian Light 1050° F.
Abstract: A low-pour fuel composition is prepared by blending with a gas oil a minor amount of a high asphaltene residuum, such as an Arabian Light 1050° F. residuum, and from about 0.003 to about 0.50 weight percent of an oil-soluble copolymer which can be, for example, an ethylene-vinyl acetate copolymer or a block copolymer of the A--B--A type wherein the A block is derived from an ester of acrylic acid or methacrylic acid and an aliphatic alcohol and the B block is a copolymer of ethylene and vinyl acetate, etc.

Book ChapterDOI
TL;DR: In recent years, the liquid phase oxidation of organic substrates using transition metal compounds as catalysts has become a profitable means of obtaining industrially important chemicals Millions of tons of valuable petrochemicals are produced in this manner annually.
Abstract: In recent years, the liquid phase oxidation of organic substrates using transition metal compounds as catalysts has become a profitable means of obtaining industrially important chemicals Millions of tons of valuable petrochemicals are produced in this manner annually [1] Typical examples of such processes are the production of vinyl acetate or acetaldehyde via the Wacker process, equations (1) and (2); the Mid-Century process for the oxidation of methyl aromatics, such as p-xylene to terephthalic acid, equation (3); and the production of propylene oxide from propylene using alkyl hydroperoxides, equation (4)

Patent
09 Nov 1977
TL;DR: In this paper, a polyvinyl(dialkylthiocarbamoylthio)acetate resin expressed by the formula ##STR1## (wherein R 1 and R 2 each represent hydrogen atom or an alkyl group of C1 -C5) is provided.
Abstract: A new polyvinyl(dialkylthiocarbamoylthio)acetate resin expressed by the formula ##STR1## (wherein R1 and R2 each represent hydrogen atom or an alkyl group of C1 -C5) is provided. Said resin has a superior heavy metals-removing performance and is insoluble in organic solvents and hence very useful as an agent for removing heavy metals. Said resin is prepared by reacting a tetraalkylthiuramdisulfide expressed by a formula ##STR2## (wherein R3, R4, R5 and R6 each represent hydrogen atom or an alkyl group of C1 -C5) with a vinyl acetate polymer on heating in a solvent. Said resin is used as an agent for removing heavy metals, alone or in admixture with an auxiliary agent such as active carbon.

Journal ArticleDOI
TL;DR: In this paper, the traditional theoretical approach to emulsion polymerization is extended to include effects due to the size of each polymer latex particle, and Coupled partial differential equations are derived to describe the system and shown to reduce to the conventional Smith-Ewart equations under certain limits.
Abstract: The traditional theoretical approach to emulsion polymerization is extended to include effects due to the size of each polymer latex particle. Specific account can thus be taken of the particle size distribution in considering the growth of the colloid. Coupled partial differential equations are derived to describe the system and shown to reduce to the conventional Smith-Ewart equations under certain limits. Solutions are presented for simple models for the emulsion polymerization of styrene and vinyl acetate.