Advanced functional polymer membranes

PEEK Biomaterials in Trauma, Orthopedic, and Spinal Implants

Review of the proton exchange membranes for fuel cell applications

Future perspectives and recent advances in stimuli-responsive materials

Ion exchange membranes: State of their development and perspective

Preparation and applications of ion exchange membranes by radiation-induced graft copolymerization of polar monomers onto non-polar films

Synthesis and characterization of PVP/AAc copolymer hydrogel and its applications in the removal of heavy metals from aqueous solution

Preparation and characterization of superabsorbent hydrogels obtained by radiation induced crosslinking of polyacrylamide (PAAm), poly(acrylic acid) (PAAc), poly(vinyl alcohol) (PVA), and potassium polyacrylate (PAAcK) were investigated individually and in (PAAm)-binary systems for possible uses in agricultural fields. The swelling of the investigated hydrogels was mainly related to the type of their hydrophilic functional groups and/or the presence of polarized charges. The preparation conditions, such as irradiation dose and hydrogel blend compositions, that influence the water absorbency of PAAm/PAAcK copolymers and alter their gel content and crosslinking density were investigated. The higher the irradiation dose, the higher the gel content, and the lower the water absorbency. PAAm/PAAcK copolymer, possessing pore structure and fast swelling, was prepared by mixing the hydrogel components with a gas-forming agent, namely, ammonium carbonate. Studies were also made on the applications of such hydrogels to improve the physical and water retention properties of sandy soil for agricultural purposes. The effect of different types and amounts of hydrogels added to sandy soil on the emergence, vegetative growth, and wilting time of corn (Zea mays) plants was investigated. As the hydrogel level increased, the average of plant height, leaf width, total dry weight, corncob production, and time to wilt increased. The obtained results suggested that the PAAm/PAAcK hydrogels can improve sandy soil properties for cultivation, because they often absorb and keep water one thousand times more than their own weight, reduce watering frequency of the plants, and enhance water retention of soil matrix that results in an increase in plant growth and performance.

Radiation synthesis of hydrogels to enhance sandy soils water retention and increase plant performance

Radiation-induced degradation of chitosan for possible use as a growth promoter in agricultural purposes

The present work has focused on the possibility of accelerating the biodegradation process of low-density polyethylene (LDPE) by mixing it with starch and exposing the obtained blend to the effect of UV radiation and/or soil burial treatments. Comparable studies between the properties of untreated LDPE/starch blends and those exposed to UV irradiation and soil burial treatment were investigated. In reference to the mechanical properties of untreated blends. The tensile strength of the blends exposed to UV irradiation-soil burial treatments was reduced by 20–66%, meanwhile, the tensile strength of the blends exposed only to soil burial treatment reduced by 10–26% from the initial value according to the starch content in the blend. The changes in the thermal, structural, and morphological properties of the blends due to the photo-irradiation and/or microbial treatments were determined using differential scanning calorimetry (DSC), transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The obtained results showed that there is a synergistic effect on the LDPE/starch biodegradation process when the blends exposed to UV-sunlight and followed by soil buried treatment. This means that photo-radiation induced oxidation reaction enhanced and accelerated the biodegradability rate of LDPE/starch blends by creating oxidized LDPE/starch that is more susceptible to biotic reactions. The results suggested that it is possible to replace non-degradable polyethylene polymer by biodegradable one for controlling the lifetime of its waste.

Synergistic effect of combining UV-sunlight–soil burial treatment on the biodegradation rate of LDPE/starch blends

El-Sayed A. Hegazy

Papers

Preparation and applications of ion exchange membranes by radiation-induced graft copolymerization of polar monomers onto non-polar films

Synthesis and characterization of PVP/AAc copolymer hydrogel and its applications in the removal of heavy metals from aqueous solution

Radiation synthesis of hydrogels to enhance sandy soils water retention and increase plant performance

Radiation-induced degradation of chitosan for possible use as a growth promoter in agricultural purposes

Synergistic effect of combining UV-sunlight–soil burial treatment on the biodegradation rate of LDPE/starch blends