To address current industrial needs and modern legislation, a series of rapidly degradable and strongly adhering crosslinked polyurethanes featuring the commercially available and degradable chain-extender 2,2’-sulfonyldiethanol have been made for use as depolymerisable coatings and ‘debond-on-demand’ hot-melt adhesives. Variation of the chain-extended polyurethane (CEPU) composition, through increased hard segment content, provided a route to tailor the mechanical, adhesive, and degradable characteristics, whereby CEPUs with ultimate tensile strengths and elongation at break of up to 42.68 MPa and 17.59 e, respectively, could be achieved. The adhesive shear strength of the CEPUs was investigated on a selection of substrates with the highest shear strength observed of 7.80 MPa on aluminium. Depolymerization was triggered via exposure of the CEPUs to tetra-butylammonium fluoride (TBAF), causing the solubilisation of the CEPUs and the generation of low molecular weight species. Rapid ‘debond-on-demand’ adhesion was also achieved upon exposure to 1 M TBAF(aq), with losses in shear strength of up to 34% on aluminum when exposed for 30 minutes.

Functionalisation of polyurethane-urea oligomers with hydrogen bonding amide end groups leads to dramatic thermal, mechanical, morphological, and rheological changes of supramolecular polyurethane elastomers. This study reports the design, synthesis and characterisation of six new aliphatic thermally stable supramolecular polyurethanes (SPUs). It was found that introduction of the amide end groups affords a polymer network that is maintained by dynamic associations within the solid state of the material. Through atomic force microscopy (AFM), the aggregation of hard segments of these phase separated SPU networks was found to be more prominent with the introduction of the amide end groups. The strong hydrogen bonding associations between the amide end groups were complemented by urea-urea and urethane-urethane interactions from the main chains to enhance the self-assembly and phase separation of SPUs and also improve the mechanical, thermal and rheological properties with respect to other SPU elastomers that feature bisamide end groups. These thermally stable phase separated SPUs also displayed remarkable re-adhesive capabilities on both glass and aluminium substrates, for example, SPU2 exhibited unique reusability after seven adhesion cycles.

A series of supramolecular comb polymers (SCPs) with adhesive and healable characteristics have been generated through the copolymerisation of methacrylate monomers featuring aromatic amide functionalities with lauryl methacrylate. By varying the amide functionality and loading of the supramolecular monomers, the properties of the resulting SCPs can be tailored, ultimately providing stable films at room temperature. As the loading of the amide-bearing monomer was increased, the phase separation between the hard and soft domains was enhanced, promoting larger hard-domain aggregation, as observed via atomic force microscopy (AFM). The mechanical properties of the SCPs correlated to the loading of the amide-bearing monomers, by increasing the mol% incorporation the resulting SCPs transition from possessing high strain to high ultimate tensile strength (UTS) and Young's modulus (YM). Over several re-adhesion cycles, the SCPs were shown to retain their shear strength when thermally adhered to both glass and aluminium substrates. Additionally, the SCPs exhibited healable properties at elevated temperatures (> 45 °C) allowing for the recovery of mechanical properties post-damage.

A series of supramolecular comb polymers (SCPs) with adhesive and healable characteristics have been generated through the copolymerisation of methacrylate monomers featuring aromatic amide functionalities with lauryl methacrylate. By varying the amide functionality and loading of the supramolecular monomers, the properties of the resulting SCPs can be tailored, ultimately providing stable films at room temperature. As the loading of the amide-bearing monomer was increased, the phase separation between the hard and soft domains was enhanced, promoting larger hard-domain aggregation, as observed via atomic force microscopy (AFM). The mechanical properties of the SCPs correlated to the loading of the amide-bearing monomers, by increasing the mol% incorporation the resulting SCPs transition from possessing high strain to high ultimate tensile strength (UTS) and Young's modulus (YM). Over several re-adhesion cycles, the SCPs were shown to retain their shear strength when thermally adhered to both glass and aluminium substrates. Additionally, the SCPs exhibited healable properties at elevated temperatures (> 45 °C) allowing for the recovery of mechanical properties post-damage.

Phase transfer catalysis P.T.C is one of the most widely used techniques in the preparation of a wide range of compounds not only in organic chemistry but also a broadly useful in several other areas of chemistry. There have been extensive studies that have been used to synthesize many compounds that are biologically important with highly efficient and the percentage of the product and purity are high with perfect time. In this study, a number of chalcones were prepared and reacted with phenoxy acetamide, 4-methyl phenoxy acetamide and phenyl mercapto acetamide for the preparation of 2–pyridones compounds under phase transfer catalysis conditions. The reaction mechanism and the structure of the resulting compounds were determined using physical analysis methods IR and ¹ H-NMR. ¹³ C-NMR was also measured for some compounds.

Phase-transfer catalysis P.T.C is one of the most widely used techniques in the preparation of a wide range of compounds not only in organic chemistry but also a broadly useful in several other areas of chemistry. There have been extensive studies that have been used to synthesize many compounds that are biologically important with highly efficient and the percentage of the product and purity are high with perfect time. In this study, a number of chalcones were prepared and reacted with phenoxy acetamide, 4-methyl phenoxy acetamide and phenyl mercapto acetamide for the preparation of 2–pyridones compounds under phase transfer catalysis conditions. The reaction mechanism and the structure of the resulting compounds were determined using physical analysis methods IR and 1H-NMR. 13C-NMR was used to measure some compounds.

This research highlights the chemical modification of one of the carbon nanostructures (multi-walled carbon nanotubes-COOH) with an artificial sweetener (saccharine) to synthesize a highly efficient absorbent material (MWCNTs-CO-Sac). This material was thereafter used to the packing column in solid phase extraction of cadmium and copper divalent ions from real samples. This nano-adsorbent was diagnosed with different techniques: infrared spectroscopy (FTIR), Thermogravimetry (TG), Differential thermal analysis (DTA), powder X-ray diffraction (PXRD), energy-dispersive X-ray spectroscopy (EDX), Particle size distribution (PSD) and scanning electron microscopy (SEM). The effect of pH, sample and eluent flow rates, volume, type and concentration of eluent, volume of sample and interfering ions were studied to achieve the optimal conditions for solid phase extraction of Cd(II) and Cu(II) based on the inductively coupled plasma-optical emission spectrometry (ICP-OES). Moreover, the preconcentration factors were calculated to be 75. The results of a limit of detection (LOD) 0.07 μgL-1 and 0.09 μgL-1 for Cd(II) and Cu(II) respectively. The relative standard deviation (RSD %) of this study was 0.45% for Cd(II) and 0.51% for Cu(II). The optimized method was applied to soil and environmental water samples.

In this paper, pH-sensitive hydrogels were prepared and developed from cellulose fibers extracted from rice husks with sodium alginate by using a double cross-linker. Cellulose fibers extraction process was carried out by alkaline and bleaching treatment. Cellulose fibers were used in variable quantities to investigate their effects on swelling degree. The resulted hydrogels showed a very strong swelling (1785-2718%) in phosphate buffer solution (pH 7), good swelling (776-1195%) in pH 10, and less swelling (81-124%) in pH 4. All of these swelling degrees and more properties of the resulted cellulose fibers and hydrogels were tested and evaluated via some techniques like Infrared spectroscopy (ATR), thermal analysis (TG, DTG, DSC, and DTA), and Scanning electron microscopy (SEM). These results show that cellulose/alginate hydrogels could provide many possible applications in the biomedical, and purification of the wastewater by adsorbing pollutants.

In his study activated carbon was prepared from Helhelok stones as a raw material by using chemical activation with zinc chloride (ZnCl2) as a chemical agent with the concentration 40% for 25h at (25⁰C±2). The optimum conditions were approved in having carbonization temperature 400ᵒC for 1h to get a maximum percentage of yield 56%. Other properties of the prepared activated carbon were also studied such as pH, ash content, density, moisture content, conductivity, iodine number and methylene blue dye absorbance. Eventually the prepared activated carbon in this work has obtained good characteristics that make it play an essential role in industrial uses and compared it with commercial standard sample from B. D. H Company.

Polyethylene (HDPE) is widely used in various applications due to its chemical, physical. and biological inertness but its durability presents a great challenge when it is released in the environment. To reduce its adverse effect on environment, currently various efforts are being made to modify its properties using naturally occurring biodegradable polymers but still these modifications found to be costly and required biodegradability in polyethylene is not yet achieved. Therefore, an attempt has been made to deveop biodegradable polyethylene blends using naturally occurring polymers. In this connection biodegradable high density polyethylene (HDPE) blends were prepared by thermally blending 2.0, 5.0 and 10.0 wt % amount of naturally occurring polymers such as; chitosan (CH), cellulose(CE), starch (ST), alginate (AL), pectin (PE), shellac (SH) and xanthan (XA). The observed biodegradabilility in HDPE blends might be due to the presence of hydrolysable linkages and stereo-favourable orientations of blended natural polymers. The added polymers have played a significant role in increasing the hydrophilicity in blended HDPE and acted as a bioassimilative nutrients for seeded microorganisms. The biodegradability of HDPE-polymer blends was evaluated in presence of various fungi such as; aspergillus niger, aspergillus terreus, fusarium solani, tricoderma hariziauum and tricoderrma viride. The disinfected films of pristine HDPE and polymer blened HDPE were inoculated with these fungi and the extend of biodegrdation was evaluated after a incubation period of three months at 28 ± 1˚C. The biodegradability of HDPE-polymer blends was compared with pristine HDPE by evaluating their molecular weights, and weight percent loss in samples incubated for three months along with selected fungus. The biodegrdation in pristine HDPE and its polymer blends was confirmed by comparing their FT-IR spectra and also by evaluating the variations in their mechanical and thermal properties. A significant variation in their morphologies in prsence of fungi has confirmed biodegradation in HDPE-polymer blends in comparison to pristine HDPE films. These studies have provided sufficient evidnces to confirm the role of added natural polymers in developing a biodegradable HDPE by blending various polymers such as chitosan (CH), cellulose(CE), starch (ST), alginate (AL), pectin (PE), shellac (SH) and xanthan (XA). Out of these polymers, the chitosan is found to be quite effective as it is acted better bioassimilative nutrient for microorganisms to cause biodegrdation of HPEF in comparison to other polymers.

The current work deals with synthesis of natural polymer hydrogels (Sodium alginate-Chitosan- Arabic Gum) as beads. The beads are formulated with different polymer proportions depending on the experimental central composite (design) Response Surface Methodology (RSM) has been used. The degree of swelling in acidic and neutral mediums was investigated, analyzed, modeled and optimized statistically. A typical drug (Allopurinol) was loaded by using optimized polymer formulations. The loading capacity and the in vitro release profiles were estimated. The shape and morphological analysis for the beads before and after drug releasing have been investigated also by using Scanning Electron Microscope. The results obtained confirmed that Arabic Gum content was a significant parameter in the swelling processes regardless the pH of the swelling media. Thus, swelling indices of the beads were higher in acidic medium (pH 3.9) compared to that once in (pH 7.1), to indicate a pH-sensitive swelling behavior. An optimum RSM results for swelling indices of 504.98 % and 207.97 % were obtained in acidic and neutral medium respectively. The in vitro drug release showed equilibrium after 12 hours where as (66.1- 85.7 %) and (44-54 %) was released at pH 3.9 and 7.1 respectively. The SEM analysis of the polymer beads confirmed that the beads had lost their shape due to erosion and swelling activities after releasing of the drug.

Many biomedical applications including controlled drug delivery systems have been developed based on hydrogel technologies. Different composite hydrogels including synthetic and natural polymers can be produced to controllable systems in drug deliver application. In this study, poly vinyl alcohol (PVA)-Gelatin hydrogel membranes were prepared by the esterification reaction between hydroxyl groups of PVA and carboxyl groups of Gelatin to deliver Captopril as a model of drug. Captopril was successfully loaded into PVA-Gelatin hydrogel membrane in different ration of Gelatin (10:1, 10:2, 10:3, 10:4, 10:5, 10:6, 10:7, and 10:8). The prepared hydrogel membranes were characterized by Fourier Transforms Infrared Spectroscopy (FT-IR) and Scanning Electron Microscopy (SEM). The effects of different process parameters, like percentage of Gelatin, size distribution, swelling behavior and in vitro drug releasing from hydrogel membrane in different phosphate buffer solutions pH (7.1 and 3.9) were studied. The models of kinetics of releasing drug were investigated by using different types of mechanisms (Zero-order, First order, Higuchi’s model and Korsmeyer-Peppas Model).

Polymeric drug delivery systems are new developed technology. They can be used to support patient’s compliance. They can help to maintain uniform drug levels and increase the safety margin for high-potency drugs. Then, they decrease the number of daily doses. Thus, in this study, Poly vinyl alcohol (PVA)-Sodium alginate (NaAlg) interpenetrating polymer network (IPN) hydrogels were prepared by using Glutaraldehyde as a crosslinked. The model drug (Carbidopa) was delivered by using emulsification / solvent-evaporation method. Carbidopa was successfully loaded into PVA-NaAlg IPN hydrogels. The prepared IPN hydrogels were characterized by Fourier Transforms Infrared Spectroscopy using (FT-IR) and Scanning Electron Microscopy (SEM). The effects of different process parameters, like degree of swelling and In vitro drug releasing of IPN hydrogel in different phosphate buffer solutions pH (7.1 and 3.9) were studied. The models of kinetics of releasing drug were investigated by using different types of mechanisms (Zero-order, First order, Higuchi’s model and Hixson-Crowell model).

Semi-interpenetrating polymer network (semi-IPN) microspheres of Sodium alginate (NaAlg) and Gelatin were prepared and cross-linked with glutaraldehyde by using emulsification/solvent-evaporation method to deliver Diltiazem HCl as a model of drug. Diltiazem HCl was successfully loaded into NaAlg- Gelatin microspheres in different ratios of NaAlg and Gelatin. The prepared microspheres were characterized by Fourier Transmission Infrared Microscopy (FT-IR) and Scanning Electron Microscope (SEM). The effects of different process parameters, like percentage of polymers, swelling behavior and in vitro drug release of microspheres in different phosphate buffer solutions pH (7.1and3.9) were studied. The models of kinetics of releasing drug were investigated by using different types of mechanisms (Zeroorder, First order, Higuchi’s model and Hixson-Crowell model).