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The interactions betweenpoly(methylmethacrylate)(PMMA),poly(vinylalcohol) (PVA) poly(ethylene glycol)(PEG)as industrial biopolymers andchitosan, cellulose, starch as natural biopolymers with iodine(I 2 ) were investigated using diethyl ether as a solvent. 5% of I 2 was added to each polymer and soaked in the solvent. The interactions were investigated using concepts of the activation energy(Ea), Decisivefactor (Df) and the changing in the glass transition temperature (ΔTg , s). Therefore, the differential scanning calorimeter (DSC) was used to monitorthe thermal transitions. The optical microscope(OM) device was used to study the surface morphologies.Resultsshowed a clear depression in the glass transition temperatures (T g , s) for all polymers( as well as new colors appear) except cellulose still unaffected .It appears that cellulose molecules coated with a film prevent iodine to diffuse through the network structure of cellulose thus no effected its color or its Tg which indicates that molecular structure of cellulose quite different from that of starch and for this fact cellulose not soluble by a solvent and undigested in the human body. The depression inTg values of polymers indicate that iodine ruptures the engineering bonds of the polymers. The most effected Tg is of chitosan (lowered by 40.23˚C, this mean that iodine ruptures both hydrogen bonding through nitrogen and oxygen atoms in chitosan molecule.From T g values, it seems that iodine can acts as moderate plasticizer, by diffusing through the net of synthetic and natural biopolymers ruptures their secondary bonds result in depression of their T g except in case of cellulose.

Superabsorbent polymer (SAP) blend has been synthesized from Carboxymethyl Cellulose (CMC) , starch, and aluminum sulfate octadecahydrate cross-linker. Water Absorption Capacity (WAC), FTIR, SEM, DSC, CHO, Flame Photometer and ignition tests are carried out to determine the used CMC formula, investigate the cross-linking process, and suggest a cross-linking model. Flame Photometer results showed there are two sodium acetate groups in the CMC molecule. This result confirmed by theoretical calculations and CHO test . To investigate which of Al 3+ and SO 4 2-ions causes the crosslinking : the extraction of the cross-linked CMC/starch tested with BaCl 2 solution(showed dense white precipitate ; sulfate group not share for blend formation), NaOH solution( showed white precipitate of aluminum hydroxide; Al 3+ ion present (i.e. Al 3+ ion share in the blend structure). These results confirmed by flame test for sodium ion, which showed high Na emission energy (5.75); there is an exchange between Al and Na ions. To check that aluminum is a part of the structure, sample of the cross-linked CMC ignited. A white precipitate appear for aluminum oxide ,which confirms the presence of Al. Based on that there are three CMC molecules connected to each Al atom, theoretical calculations about the amount of Al in the cross-linked CMC molecule showed a good agreement with the CHO results (5.613% Vs. 5.739 % respectively). FTIR spectrum of the cross-linked CMC/starch blend showed that there is a reaction between CMC and starch molecules; i.e. the new repeating unit contains three starch molecules. This conclusion confirmed by theoretical calculations and results of EDX, CHO, and ignition tests. Al% in the new mer appeared a good agreement between theoretical calculations (4.32%) and CHO results (4.512%). Ignition test calculations confirmed that the new mer contains three Al atoms. Evidences of the occurrence of the cross-linking process were obtained from FTIR, morphology, DSC and absorbency results. Absence of the primary hydroxyl alcohol band in the CMC/starch blend spectrum, indicates that this site is active and the reaction between starch and CMC molecules occurs through it. Morphologies studies showed that the sample after crosslinking is more compact than before as well as show one piece for after cross-linking comparing with different pieces before cross-linking.Optimum cross-linking ratio appeared to be 2wt% corresponded to WAC equal to 58 g/g.in distilled water and DSC results indicates that CMC/starch is a miscible blend.

In this work, a series of Natural Rubber (NR)/Styrene Butadiene Rubber (SBR) blends were formulated to protect metallic petrochemical storage tanks from corrosive media. Therefore, these blends tested against a 10% HCl solution for 72 hr at room temperature. Blends series were prepared with different ratios of NR/SBR; 25/75, 30/70, 35/65, 40/60, 45/55, 50/50, and 55/45. Three types of carbon black (N-330, N-660, and N-762) were added individually to the 45/55 blend. Hardness, tensile strength, modulus, and elongation properties were tested before and after immersion in the 10% HCl attack media. All these mechanical properties decreased after immersion action accept hardness property. Up to 45 phr NR content, the hardness increased linearly independent on immersion action, but HCl immersion gives higher hardness values. Tensile strength increased up to 40 phr NR content with and without immersion and the immersion action decreased tensile values. The highest elongation value obtained with 35/65 blend with and without immersion. The 45 phr NR content gives the higher modulus, while the lowest value obtained with the 30 phhr content. For 45/55 blend, the hardness increased as the carbon black particle size decreased and immersion action gives higher hardness values. The tensile strength decreased linearly with the carbon black surface area, while with the medium surface area, the highest modulus and lowest elongation obtained.

Uncross-linked carboxymethyl cellulose (CMC) / starch blend used to prepare two hydrogels; the first is crosslinked CMC / starch with aluminum sulfate octadecahydrate cross-linker and the second is SHNCs manufactured from incorporation of 0.3wt% nano graphite oxide (GO) in the above cross-linked blend. Viscoelastic and rheological properties of these two hydrogels were studied and compared with the uncross-linked blend. Results showed that the cross-linking process increases the blend miscibility and converted it to miscible blend. The SHNCs hydrogel has the higher T g and the uncrosslinked blend has the higher Tan δ. GO addition causes increment in some viscoelastic parameters such as G*, G', and G", and decrement in damping parameters and make the damping behavior more stable at lower frequencies, and causes increment for all rheological parameters (η* , η o , η f , and G N o ). GO addition leads, also, to the absence of the shear thickening behavior and increases both the entanglement density and the molecular weight average. Both hydrogels exhibited broad molecular weight distribution (MWD) and highly cross-linking degree and their elastic behavior predominates; makes them rigid specially at higher frequencies.

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