Hydrolysis of Magnetic Amylase-Imprinted Poly(ethylene-co-vinyl alcohol) Composite Nanoparticles

A new procedure has been developed, which is based on homogeneous precipitation of organized mesoporous silica from an aqueous solution of sodium metasilicate and a nonionic poly(ethylene oxide) surfactant serving as a structure-directing agent. The decrease in pH, which induces the polycondensation of silica, is achieved by hydrolysis of ethyl acetate. Owing to the complexation of Na+ cations by poly(ethylene oxide) segments, assembling of the mesostructure appears to occur under electrostatic control by the S0Na+I- pathway, where S0 and I- are surfactant and inorganic species, respectively. As the complexation of Na+ cations causes extended conformation of poly(ethylene oxide) segments, the pore size and pore volume of organized mesoporous silica increase in comparison with materials prepared under neutral or acidic conditions. The assembling of particles can be fully separated from their solidification, which results in the formation of highly regular spherical particles of mesoporous silica.

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Influence of the polymer molecular weights on the electrical properties of Poly(vinyl alcohol) – Poly(ethylene glycols)/Graphene oxide nanocomposites

Materials Today Proceedings ◽

10.1016/j.matpr.2020.12.565 ◽

2021 ◽

Author(s):

Shurooq S. Al-Abbas ◽

Rusul A. Ghazi ◽

Athmar K. Al-shammari ◽

Nisreen R. Aldulaimi ◽

Ali R. Abdulridha ◽

...

Keyword(s):

Graphene Oxide ◽

Electrical Properties ◽

Vinyl Alcohol ◽

Poly Vinyl Alcohol ◽

Molecular Weights ◽

Ethylene Glycols ◽

Poly Ethylene

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Thermal Properties, Isothermal Decomposition by Direct Analysis in Real-Time-Of-Flight Mass Spectrometry and Non Isothermal Crystallization Kinetics of Poly(Ethylene-Co-Vinyl Alcohol)/Poly(ε-Caprolactone) Blend

Crystals ◽

10.3390/cryst11030292 ◽

2021 ◽

Vol 11 (3) ◽

pp. 292

Author(s):

Abdulaziz Ali Alghamdi ◽

Hussain Alattas ◽

Waseem Sharaf Saeed ◽

Abdel-Basit Al-Odayni ◽

Ahmed Yacine Badjah Hadj Ahmed ◽

...

Keyword(s):

Mass Spectrometry ◽

Real Time ◽

Crystallization Kinetics ◽

Isothermal Crystallization ◽

Vinyl Alcohol ◽

Time Of Flight ◽

Direct Analysis ◽

Isothermal Crystallization Kinetics ◽

Flight Mass Spectrometry ◽

Poly Ethylene

A series of poly(ethylene-co-vinyl alcohol)/poly(ε-caprolactone) blends with different compositions were prepared using solvent casting. The miscibility of this pair of polymers was investigated using differential scanning calorimetry (DSC), and proved by a negative Flory interaction parameter value calculated from the Nishi–Wang equation. The miscibility of this blend was also confirmed by scanning electronic microscopy (SEM). The thermal behaviors of the obtained materials were investigated by DSC, thermogravimetric analysis, and direct analysis in real-time–time-of-flight mass spectrometry and the results obtained were very relevant. Furthermore, the crystalline properties of the obtained materials were studied by DSC and X-ray diffraction where the Ozawa approach was adopted to investigate the non-isothermal crystallization kinetics. The results obtained revealed that this approach described the crystallization process well.

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Effect of Cobalt Stearate and Vegetable Oil on Uv and Biodegradation of Linear Low-Density Poly(Ethylene)-Poly(Vinyl Alcohol) Blends

Polymers from Renewable Resources ◽

10.1177/204124791100200401 ◽

2011 ◽

Vol 2 (4) ◽

pp. 131-148 ◽

Cited By ~ 1

Author(s):

Francis Vidya ◽

Subin S. Raghul ◽

Sarita G Bhat ◽

Eby Thomas Thachil

Keyword(s):

Vegetable Oil ◽

Vinyl Alcohol ◽

Water Soluble ◽

Poly Vinyl Alcohol ◽

Low Density ◽

Compression Moulding ◽

Melt Mixing ◽

Degradation Behaviour ◽

Moulding Process ◽

Poly Ethylene

The main objective of this study was to enhance the rate of UV and biodegradation of polyethylene by incorporating biodegradable materials and prooxidants. Prooxidants such as transition metal complexes are capable of initiating photooxidation and polymer chain cleavage, rendering the product more susceptible to biodegradation. In this work, the effect of (1) a metallic photoinitiator, cobalt stearate, and (2) different combinations of cobalt stearate and vegetable oil on the photooxidative degradation of linear low-density poly(ethylene)-poly(vinyl alcohol) (LLDPE/PVA) blend films has been investigated. For this, film-grade LLDPE was blended with different proportions of PVA. PVA is widely used in the industrial field, and recently it has attracted increasing attention as a water-soluble biodegradable polymer. Cobalt stearate and vegetable oil were added to the blends as prooxidants. The blends were prepared by melt mixing in a Thermo HAAKE Polylab system. Thin films containing these additives were prepared by a subsequent compression moulding process. The effect of UV exposure on LLDPE/PVA films in the presence as well as absence of these additives was investigated. Tensile properties, FTIR spectra, and scanning electron microscopy (SEM) were employed to investigate the degradation behaviour. It was found

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