Aims and Scope
Water Absorption Enhancement of Sodium Poly Acrylate and Poly(2-Acrylamido-2-Methylpropane Sulphonic Acid) Based Hydrogel MixturesSohair A. Darwish, Ibrahim M. Ibrahim, Nasser Y. Mostafa, Mostafa A. Radwan, Mohamed A. Sadek, Hany A. Elazab
Hydrogels are hydrophilic polymers which are cross-linked to form three-dimensional structures, which can absorb, swell and retain huge amounts of water or aqueous fluids.
This paper reports the preparation and characterisation of Poly(2-Acrylamido-2-Methylpropane Sulphonic Acid) (PAMPS) hydrogel with different crosslinking intensities.
2-Acrylamido-2-methylpropane sulfonic acid (AMPS) monomer was purchased from Alfa Aesar Company as reagent grade. It was used as received (>98% purity) without any further purification.
PAMPS hydrogel was prepared by free radical crosslinking solution polymerization of AMPS in water at room temperature under a nitrogen blanket in cylindrical glass tubes. The characteristics of the obtained PAMPS hydrogel were compared with those of commercial sodium polyacrylates hydrogel.
It was found that decreasing the crosslinker weight improved the absorbance capacity but to a limit. The suggested reasons were discussed. The mixture showed higher absorbance rate than PAMPS, and bigger absorbance capacity than sodium polyacrylates.
This paper investigates the effect of crosslinker ratio on the swelling capacity of PAMPS. It was found that as the crosslinking ratio decreases, the porosity of the hydrogel increases, thus improving the swelling capacity.
December 24, 2021
- November 17, 2021
- August 27, 2021
- June 22, 2021
- August 27, 2021
- December 24, 2021
Analysis of the Effect of Separate Collection on the Composition of Mixed Municipal Solid Waste in ItalyPaolo S. Calabrò, Domenica Pangallo
Separate collection of municipal solid waste (MSW) is mandatory in Italy, and an increasingly higher standard of efficiency is applied; in fact, the target value set by regulation is 65%.
In the last 20 years, separate collection efficiency increased from 9.4% with 80% national MSW landfilled, and only one region was over 25% separate collection to 58.1% with 22% national MSW landfilled and 12 of 20 regions over 55% separate collection. However, significant differences are present in the three Italian macro regions (North, Center and South).
This paper analyzes the composition of waste carried in most Italian regions to evaluate the effect of separate collection on the composition of mixed municipal solid waste (unsorted). Moreover, a regression analysis on the same data allows to assess this latter as a function of separate collection efficiency.
August 18, 2020
- October 31, 2017
- October 12, 2017
- July 28, 2017
- July 21, 2017
- October 28, 2016
- June 03, 2016