Search results for "Ethylene-vinyl acetate"
showing 9 items of 9 documents
Evaluation of the bending behaviour of laminated glass beams via electronic speckle pattern interferometry
2017
The paper is devoted to the experimental analysis of the kinematical and mechanical behaviour of laminated glass beam structures. In particular, the utilized laminated glass specimens are composed of two glass layers bonded by a polymer layer constituted by Ethylene-vinyl acetate whose thickness has been nominally considered as constant for all the specimens. The experimental behaviour of the analyzed specimens is deduced by applying Electronic Speckle- Pattern Interferometry technique; actually, among optical methods this technique (handled by phase-stepping technique) is very effective to obtain a full-field displacement map and to numerically achieve the longitudinal strain. In particula…
Recycled Polycarbonate Based Nanocomposites
2013
Post-consumer polycarbonate (RPC) blends with various amounts (5, 10, 30 wt. %) of ethylene vinyl acetate copolymer (EVAc) are investigated as potential nanocomposite matrices. At EVAc weight content of 10 wt.% maximum tensile strength σM and impact strength AI increase is observed in comparison to neat RPC. Addition of EVAc, however, reduces resistance to creep as well as decrease thermal stability of the investigated compositions. Addition of montmorillonite nanoclay (MMT), however, allows increase modulus of elasticity E and yield strength σY of the investigated RPC blend with 10 wt. % of EVAc. Besides it creep resistance and thermal resistance of the investigated system is increased to …
Evolution of the morphology and characterzation of compatibilized PBT/EVA blends prepared by reactive extrusion
2006
In this work, the possibility of preparing compatibilized blends of poly(butylene terephthalate) (PBT) and an ethylene vinyl acetate (EVA) copolymer by reactive extrusion in the presence of an ethylene acrylic acid copolymer (EAA) and a bisoxazoline compound (PBO) as compatibilization promoters has been studied. In addition, the evolution of the morphology of the blends under different annealing conditions in the presence and absence of the compatibilizing promoters has been studied. Binary blends of PBT and EVA showed behavior typical of incompatible blends with a gross morphology and bad mechanical performance. The situation was however different for ternary PBT/EVA/EAA and especially for…
Recycled Polycarbonate Blend as Matrix for Development of Polymer Nanocomposite
2012
Summary: Secondary polycarbonate (SPC) is modified with various amounts (5, 10, 30 wt%) of ethylene vinyl acetate copolymer (EVAc) in order to reduce its brittleness. It is observed that at optimal EVAc weight content maximum tensile strength σM and impact strength AI increse by 14% (ωEVAc = 5 wt%) and 450% (ωEVAc = 10 wt%) in comparison to neat SPC, respectively. Addition of montmorillonite nanoclay (MMT) allowed further increase of elastic modulus E, strength and creep resistance of the investigated SPC blend with 10 wt% of EVAc.
Stability of parenteral nutrition admixtures containing organic phosphates
1995
The use of organic phosphates to avoid calcium phosphate precipitation in parenteral nutrition mixtures has been proposed. The purpose of this study was to evaluate the stability of total parenteral nutrition admixtures containing glucose-1-phosphate or glycerol phosphate as the phosphate source over 3 days. Three parenteral nutrition admixtures, each containing glucose-1-phosphate (30.0 mmol), glycerol phosphate (31.4 mmol) or inorganic phosphate (30.0 mmol), and their corresponding aqueous phases were prepared in 3-L ethylene vinyl acetate plastic bags and infusion bottles, and stored at 5 +/- 1 degrees C or 22 +/- 3 degrees C without light protection. Physical stability analysis and samp…
Composites of ethylene-vinyl acetate copolymers with modified magnesium hydroxide-thermo-oxidative ageing
2014
Flame retardant composites must perform their protective roles permanently, also under conditions of intermittent or long-term exposure to sunlight, moisture or increased temperature. The aim of our work was characterization of the thermo-oxidative ageing (90 °C) and the changes in flammability of ethylene-vinyl acetate copolymer composites with 40 and 60 wt.% of magnesium hydroxide. The neat polymer and its composites were investigated for their thermal (DSC) and structural (FTIR) characteristics as well as their density, melt flow index, tensile properties and combustibility during ageing test. As FTIR results identified the different carbonyl groups in copolymer were created, the highest…
Ethylene-vinyl Acetate Thermoplastic Copolymers Filled with Multiwall Carbon Nanotubes: Effect of Hydrothermal Ageing on Mechanical, Thermal, and Ele…
2013
A range of properties of two commercial thermoplastic ethylene-vinyl acetate (EVA) copolymers, Elvax 420 and Elvax 450, neat and as melt-mixed composite filled with 15 wt.-% of multi-wall carbon nanotubes (MWCNTs), are studied in the “as produced” state and after hydrothermal ageing. Addition of MWCNTs into the neat copolymers introduces the functionality of electrical conductivity and significantly improves their mechanical properties, while thermal characteristics are slightly affected by the presence of carbon nanotubes. A remarkable increase of the elastic modulus (150%) and stress at failure (50%) in stress–strain experiments as well as creep resistance (40%) of the nanocomposites in c…
Branched polymers starting from ethylene-vinyl acetate copolymers
1995
Abstract Polyethylene-graft-poly-2-phenyl-2-oxazoline, polyethylene-graft-poly-2-methyl-2-oxazoline and polyethylenegraft-poly(ethylene oxide) were prepared using poly(ethylene-co-vinyl chloroformate) as macroinitiator or polyfunctional precursor. The vinyl acetate groups of ethylene-vinyl acetate copolymer were hydrolyzed, the corresponding alcohol functions were converted into chloroformate, which in turn was used for grafting of oxazolines. Comb-like polymers with hydrophilic poly(ethylene oxide) grafts with definite length were synthesized as well. The resulting graft copolymers were characterized by GPC, IR, and 1 H-NMR spectroscopy and differential scanning calorimetry.
Reactive Compatibilization of PBT/EVA Blends with an Ethylene-Acrylic Acid Copolymer and a Low Molar Mass Bis-Oxazoline
2004
Polyesters and polyolefins form highly incompatible blends with poor properties and gross morphology that hinder any practical applications. In this work, the possibility to compatibilize an incompatible blend of poly(butylene terephthalate) (PBT) with ethylene vinyl acetate (EVA) by adding a bis-oxazoline compound, 2,2'-(1,3-phenylene)-bis(2-oxazoline) (PBO), and an ethylene acrylic acid copolymer (EAA) as compatibilizer precursors has been studied. The results indicate that the binary uncompatibilized blends show poor mechanical properties and a bad morphology with scarce adhesion between the phases. The situation is only slightly improved when the EAA is added while the best performance …