scispace - formally typeset
Search or ask a question
Topic

Vinyl acetate

About: Vinyl acetate is a research topic. Over the lifetime, 15970 publications have been published within this topic receiving 162142 citations. The topic is also known as: Ethenyl acetate & Ethenyl ethanoate.


Papers
More filters
Journal ArticleDOI
TL;DR: The thickness of films of poly(methyl methacrylate) (PMMA), poly(vinyl acetate) (PVAc), and polystyrene (PS) adsorbed on Pyrex glass was studied by measuring the flow rates of polymer solutions and the corresponding pure solvents through sintered filter disks as mentioned in this paper.
Abstract: The thickness of films of poly(methyl methacrylate) (PMMA), poly(vinyl acetate) (PVAc), and polystyrene (PS) adsorbed on Pyrex glass was studied by measuring the flow rates of polymer solutions and the corresponding pure solvents through sintered filter disks. Adsorption isotherms were in agreement with those reported by other workers and showed saturation adsorption equivalent to 2–8 condensed monolayers of monomer units. Film thicknesses were of the order of magnitude of the free coil diameters in solution and were directly proportional to the intrinsic viscosity of the polymer, except for PS in benzene where the thicknesses leveled off as molecular weight increased. It was concluded that polymers adsorb from solution in monolayers of compressed or interpenetrating coils; that below some critical molecular weight which varies with polymer and solvent, a much larger fraction of the segments lies directly in the interface; that adsorbed films may consist of a dense layer immediately adjacent to the surface and a deep layer of loops extending into the solvent; and that it is the segment—solvent interaction rather than the segment—surface interaction which dominates the conformation of the adsorbed chain.

47 citations

Journal ArticleDOI
TL;DR: In this paper, LiBF4, LiClO4, and LiCF3SO3 were obtained as a function of frequency at various temperatures ranging from 302 to 363 K. The maximum room temperature ionic conductivity was found to be 1.18 × 10−3 S cm−1 for the film containing LiBF 4 and the temperature dependent ionic conductsivity values seem to obey VTF relation.
Abstract: Solid polymer electrolytes comprising poly(vinyl acetate) (PVAc), and poly(vinylidene fluoride-co-hexafluoropropylene) (PVdF-co-HFP), low molecular weight plasticizer [Ethylene Carbonate (EC)] and different lithium salts (LiBF4, LiClO4, and LiCF3SO3) are prepared by solution casting technique. The electrolyte films are subjected to various characterization techniques such as XRD, FTIR, DSC, SEM and ac impedance analysis. Ionic conductivity is obtained as a function of frequency at various temperatures ranging from 302 to 363 K. The maximum room temperature ionic conductivity is found to be 1.18 × 10−3 S cm−1 for the film containing LiBF4 and the temperature dependent ionic conductivity values seem to obey VTF relation. Microstructure of the samples has been depicted by means of scanning electron microscope. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010

47 citations

Journal ArticleDOI
TL;DR: In this paper, generalized two-dimensional correlation spectroscopy has been applied to the study of the composition-dependent near-infrared (NIR) spectral changes in 11 different ethylene/vinyl acetate (EVA) copolymers with vinyl acetate content from 6 to 42 wt%.
Abstract: Generalized two-dimensional (2D) correlation spectroscopy has been applied to the study of the composition-dependent near-infrared (NIR) spectral changes in 11 different ethylene/vinyl acetate (EVA) copolymers with vinyl acetate (VA) content from 6 to 42 wt%. The 2D synchronous correlation analysis of the 11 NIR spectra has separated the bands due to ethylene units from those due to the VA units. The obtained results are consistent with those reached by the calculation of the second derivative and by chemometrics analysis reported in our previous paper. However, the 2D correlation analysis has given clearer evidence for the band separation. Two-dimensional asynchronous correlation analysis has revealed out-of-phase variations between some bands due to ethylene and some bands due to VA and has determined the order of intensity change between them. On the basis of the order of intensity change, the bands of ethylene in the orthorhombic crystalline phase have been discriminated from those in the amorphous and disordered phases. This paper discusses the potentials of three powerful techniques, 2D correlation analysis, the calculation of the second derivatives, and that of regression coefficients in chemometrics, in unraveling rather complicated NIR spectra.

47 citations

Journal ArticleDOI
TL;DR: The effect of pristine silica nanoparticles on a model low-density polyethylene (LDPE)-ethylene vinyl acetate copolymer (EVA) thermoplastic elastomer blend system is explored in this article.
Abstract: The effect of pristine silica nanoparticles on a model low-density polyethylene (LDPE)-ethylene vinyl acetate copolymer (EVA) thermoplastic elastomer blend system is explored in this article. Pristine silica nanoparticles were melt-blended with the LDPE-EVA system at 1.5, 3, and 5 wt % loadings through the variation of the sequence of addition. In one of the compositions, coupling agent bis[3-(triethoxysilyl)propyl] tetrasulfide (Si-69) was used to improve the interaction of hydrophilic silica fillers with the polymer matrix. The blends were compression-molded, and their mechanical, dynamic mechanical, and thermal properties, X-ray diffraction patterns, and morphology were evaluated. The properties of the blends were found to be strong functions of the sequence of addition of nanofillers during their preparation. With Si-69 as a coupling agent, the dynamic storage modulus of nanosilica-based composites was found to increase up to 35%. An appreciable improvement in the tension set properties of the thermoplastic elastomer nanocomposites was observed in all the nanosilica-based films. Morphological studies and dynamic properties clearly indicated that the differential properties of these blend systems primarily stemmed from the extent of dispersion and alternation of crystalline morphology, which in turn was a strong function of preferential incorporation in the LDPE or EVA matrix and the agglomeration tendency of the nanofillers.

47 citations

Journal ArticleDOI
TL;DR: In this paper, a radical crosslinking copolymerization (RCC) was used to synthesize polyvinyl acetate (PVAc) nanogels in the presence of xanthate as a reversible chain transfer agent.
Abstract: Poly(vinyl acetate) (PVAc) nanogels are synthesized by a radical crosslinking copolymerization (RCC) in solution of vinyl acetate and divinyl adipate (DVA) or 2,4,6-tris(allyloxy)-1,3,5-triazine (TAT) as the crosslinker, in the presence of a xanthate as a reversible chain transfer agent. Higher concentrations of crosslinker and lower concentrations of xanthate produce PVAc nanogels of higher molar masses, for a given concentration of xanthate and for a fixed concentration of crosslinker, respectively. The xanthate end-groups allow for the synthesis of ‘second generation’ nanogels through a subsequent RCC from precursors. The chemical cleavage of the crosslinks yields individual poly(vinyl alcohol) chains, which attests that the length of the constitutive chains is controlled by the xanthate.

46 citations


Network Information
Related Topics (5)
Copolymer
84K papers, 1.2M citations
95% related
Polymerization
147.9K papers, 2.7M citations
94% related
Polymer
131.4K papers, 2.6M citations
93% related
Nanocomposite
71.3K papers, 1.9M citations
87% related
Self-healing hydrogels
34.9K papers, 1.2M citations
84% related
Performance
Metrics
No. of papers in the topic in previous years
YearPapers
202389
2022142
2021157
2020199
2019277
2018351