This research is focused on the synthesis and the ability to inhibit scale and corrosion of poly(acrylic acid-co-acrylamide) (PAA-AM copolymers). A series of polymers were synthesized by free radical polymerization having various weight ratios of acrylic acid (AA) to acrylamide (AM). The structures of the synthesized polymers were characterized by UV-Vis Spectroscopy, FT-IR, and 1H-NMR. The thermal stability of the polymers was analyzed by a TGA technique. The water solubility of the polymers was examined using a turbidity meter. The scale inhibition performance test was performed by titration of calcium ion with ethylene diamine tetraacetic acid (EDTA) solution. After that, the crystal structure of CaCO3 scale from the scale inhibition test was examined using a scanning electron microscope. The efficiency of the corrosion inhibitor on low carbon steel AISI 1018 was investigated by a potentiodynamic polarization technique. The result show that PAA-AM copolymers having a 9:1 weight ratio with 45.82% at 100 ppm inhibited scale forming. The corrosion resistance of all inhibitors could be achieved when the concentration of the inhibitor was lower than 100 ppm.

Carboxylated polymer can be used as an anti-scaling agent in circulating water cooling systems. Poly(acrylic acid) and homopolymer have some drawbacks such as slight solubility in water and low calcium tolerance leading difficulty to determine the remaining quantity of polymer in water. This research is mainly focused on synthesis and ability of poly(acrylic acid-co-2-acrylamido-2-methylpropane sulfonic acid) (PAA-PAMPS) for scale inhibition. These terpolymers varied in mole ratios of monomers were prepared via solution polymerization. The obtained polymers are then characterized by FT-IR, 1H-NMR, TGA, turbidity, and UV-visible spectroscopy. For a scale inhibition test, GB/T 16632-2008 standard is applied. The scale inhibition efficiency for 100% was found in PAA-PAMPS copolymer (7:3). Afterwards this polymer was chosen for synthesizing an ultraviolet-tagged PAA-PAMPS-PNaSS terpolymer. UV-visible spectroscopy was used to monitor benzene sulfonate structure in sodium styrene sulfonate of the polymer chain at 224 nm.

In most scenarios, there tend to have some impurities such as organic and inorganic substances found on the surface water. These impurities can be classified as insoluble and soluble compounds which in turn, can be purified by filtration and sedimentation prior used. Calcium carbonate (CaCO3), is one of the most contaminated compounds on surface water, mainly causes severe damage to industrial parts. Therefore, CaCO3 need immediate removal from raw water before applied to an unit operation by coagulation and flocculation. We mainly focused on precipitation of synthetic water and raw water with polyaluminium chloride (PAC) and synthetic polymer flocculants in this research study. The synthetic flocculants of Polyacrylic acid (PAA), Polyacrylamide (PAM) and Poly (acrylic acid-co-acrylamide) (PAAAM) by free radical polymerization in aqueous. The PAAAM is synthesized in various mole ratio of acrylic acid and acrylamide of 9:1 to 5:5. The polymer flocculants are characterized by FT-IR and 1H-NMR techniques. The FTIR spectra of the sample showed absorption frequency above HYPERLINK "tel:3200-3000" \t "_blank" 3200-3000, 1750-1550 and 1650-1500 corresponding to OH and CO stretching and NH bending respectively. The 1H-NMR spectra of PAM showed chemical shift at 1.50, 2.10 and 4.20 ppm regarding to proton of methyl, methylene and amide group respectively and the present of proton resonances at 1.50 and 2.30 ppm regarding to proton of methyl and methylene of PAA. The removal efficiency of suspended CaCO3 is measured and calculated via turbidity technique. The dosage of PAC 0.1 ppm can remove suspended CaCO3 approximately 65.33% after the PAAAM with mole ratio of 8:2 is applied to system lead to the removal efficiency increasing to 99.03%.

Calcium sulfate dihydrate (CaSO4•2H2O, CSD), gypsum is a by-product in the production of citric acid (citryogypsum). This by-product could neither be exploited nor distributed as a reactant because of its physical properties including those that are not equivalent to natural gypsum. Moreover, the mentioned citrogypsum has been continually increasing environmental problems. Therefore, this research aims at how to recycle gypsum that is synthesized by hydrothermal method at 95oC for 7 hrs under the atmospheric pressure via different solutions (MeOH, EtOH, PrOH, BuOH and Hexane). In order to produce alpha-calcium sulfate hemihydrate (α-CaSO4•0.5H2O, α-CSH) with improved physical properties that will be used for different industries. FT-IR reveals the chemical composition of crystal and the adsorption of methyl group on the surface. Besides, TGA thermogram shows the theoretical crystal water content of CSD and α-CSH 20.9 wt% and 6.2 wt% respectively. The DSC thermogram, shows that endothermic peaks at 151.2 oC and 168.5 oC. There were two steps of loss at 1.5 and 0.5 water molecule respectively. With SEM images of crystal shows the plate-like shape of citrogypsum, while α-CSH shows the hexagonal shape excluding hexane solution. Of all the results, the polarity of solution has an impact on the transition of CSD to α-CSH under this condition.

Hydrogel is very popular used in medicinal materials due to their properties. The aim of study is to investigate the development of chitosan (CS) hydrogel beads to extend drug-releasing time and enhance the stability of hydrogel beads from decomposition due to surrounding temperature. Gentamicin (GM) is using as a drug model for loading and releasing from hydrogel beads. For this purpose, the effects of ionic gelation of CS and tripolyphosphate (TPP) on various concentrations (1, 3, 5, and 7%w/v) are emphasized. Scanning electron microscopy (SEM) has revealed that CS hydrogel beads are roughly surface with decreasing of the %CS content. The Fourier transform infrared (FT-IR) spectra show a weak band of hydroxyl stretching at 2878 cm-1 of chitosan, the absorption band of the carbonyl stretching of the secondary amide at 1651 cm-1. The releasing solution of CS hydrogel beads exhibit an antimicrobial activity against 4 type of bacterias compared to Chloramphenical. For this reason, indicating that CS hydrogel beads are an appropriate for controlled drug release system to turmeric crude extract.