The electron beam Radiation technique has been explored as the latest and most effective means of forming chemically active sites on LDPE surface. In this novel work a solventless grafting of 2-hydroxyethyl methacrylate (HEMA) on to LDPE surface was conducted. Thus prepared active sites were exploited to subsequently solventless graft copolymerization of HEMA onto LDPE by high energy electron beam Radiation (10 MeV) at dose range of 10 up to 200 kGy at atmospheric pressure in air. As HEMA could not wet LDPE surface, its synthesized tacky polymer was used for coating and then grafting purposes. LDPE film and sheet surfaces were impregnated with the prepared adhesive and were irradiated. FTIR Spectra showed that the concentration of characteristic bonds of poly(HEMA-g-LDPE) (C=O in ester groups, in hydroxyl groups as C-OH, and ether carbon bonds as C-O) increased with increasing irRadiation dose, also, the percentage of grafting significantly increased up to 60%. The hydrophilicity of the grafted surface considerably increased compared to that of the ungrafted ones as contact angle measurements showed a 72% decrease. Furthermore, the yields of gel content measurement were investigated and the topology of the surface and cross-section of poly(HEMAg- LDPE) films and sheets was studied by means of SEM. Moreover, the mechanism of achieving up to 70% cross-linked network in solid semi-crystalline LDPE is discussed.

Poly N-isopropylacrylamide was successfully grafted onto a polystyrene cell culture dish by gamma ray. In this study, the effect of a Radiation dose (Radiation absorbed dosages of 10, 20, 30, 40 KGy) under appropriate temperature and grafting conditions was investigated. The FTIR analysis showed the existence of the graft PNIPAAm on the substrate. The optimal value of the dose for grafting was 40 KGy at 50°C. The SEM and AFM images clearly showed that increasing the absorbed dose of Radiation would increase the amount of grafting. Surface topography and graft thickness in AFM images of the radiated samples showed that the PNIPAAm at the absorbed dose of Radiation was properly grafted. The thickness of these grafts was about 50–100 nm. The drop water contact angles of the best grafted sample at 37oC and 10°C were 55.3±1.2o and 61.2±0.9o respectively, which showed the hydrophilicity and hydrophobicity of the grafted surfaces. DSC analysis also revealed the LCST of the grafted sample to be 32oC. Thermo-responsive polymers were grafted to dishes covalently which allowed fibroblast cells to attach and proliferate at 37oC; the cells also detached spontaneously without using enzymes when the temperature dropped below 32oC. This characteristic proves that this type of grafted material has potential as a biomaterial for cell sheet engineering.

The electron beam Radiation technique has been explored as the newest and most effective means of forming chemically active sites on LDPE surface. In this novel work the solventless grafting of HEMA onto LDPE surface was conducted. Thus the prepared active sites were exploited to subsequently solventless graft copolymerization of HEMA onto LDPE by high energy electron beam Radiation (10 MeV) at dose range of 10 up to 200 kGy at atmospheric pressure in air, in the absence of solvent. As HEMA could not wet LDPE surface, its synthesized tacky polymer was used for coating and subsequent grafting purposes. LDPE Film and sheet surfaces were impregnated with the prepared adhesive and then were irradiated. The FTIR spectra of poly(HEMA-g-LDPE) showed that the concentration of characteristic bands of C=O in ester groups, C-OH in hydroxyl groups and –C-O in ether carbon bonds increased with increasing dose as well as the percentage of grafting significantly increased up to 60%. The hydrophilicity of the grafted surface considerably increased compared to that of the ungrafted ones as the contact angle measurements showed a 72% decrease. Furthermore, the yields of gel content measurement were obtained and the topology of the surface and cross-section of poly(HEMA-g-LDPE) films and the sheets were studied by means of SEM. Moreover, the mechanism of achieving up to 70% cross-linked network in semi-crystalline solid LDPE is discussed.

A carboxylic acid chelating fiber with high adsorption capacity for copper ions was prepared by grafting acrylic acid onto polypropylene fiber using pre-irRadiation method. Effects of reaction conditions such as pH, initial copper concentration and adsorption time were discussed. The results showed that carboxylic acid chelating fiber is effective for the removal of copper ions in the range of pH=4.0-7.0. The chelating fiber also showed much higher capacities for copper, the equilibrium adsorption amount could be 24.35 mg/g for copper adsorption This chelating fibers exhibited good potential application in removal of copper ions in aqueous solution.

Radiation grafting of two hydrophilic monomers (i.e., acrylamide and acrylic acid) onto styrene-butadiene rubber (SBR) and natural rubber (NR) by the simultaneous method was studied. Attempts to graft SBR and NR in aqueous solution of. acrylic acid and acrylamide lead to extensive homopolymerization. Metal-based homopolymerization inhibitors including Mohr"s salt and cupric nitrate were evaluated and found to prevent homopolymerization and significantly increase graft yield. The role of substrate structure on grafting efficiency for two hydrophilic monomers was investigated. The properties of the resulting copolymers have been studied by SEM techniques.

This work aims at modelling and characterizing the kinetics of biodegradation of acrylic acid-grafted polypropylene. Different films of acrylic acid-grafted polypropylene were prepared. These films were degraded aerobically during thermophilic phase of composting process for measurement of carbon dioxide evolution as per ASTM D 5338. The experimental data were analyzed using an eight-parameter Komilis model containing a flat lag phase. The model formulations involved hydrolysis of primary solid carbon and its subsequent mineralization. The first step was rate controlling and it included hydrolysis of primary slowly, moderately, and readily hydrolyzable carbon fractions in parallel. The model parameters were evaluated by means of nonlinear regression technique. The model parameters, undegraded/hydrolyzable/mineralizable carbon evolutions and morphology revealed two typical kinetic regimes. The first five films exhibited slow degradation in the first regime involving slowly and moderately hydrolyzable carbons. They exhibited low degradability value in the range of 1. 5–, 3. 7% in 45 days. Their degradability decreased with an increase in the slowly hydrolyzable carbon refractory in nature. The remaining three films exhibited the second regime involving the moderately and readily hydrolyzable carbons. These showed relatively high degradability in the range of 4. 7–, 5. 6% in 45 days. The magnitudes of their moderately hydrolyzable carbon fractions were substantially higher than those of the first regime. All the eight films showed the absence of growth phase because of their small initial readily hydrolyzable carbon fractions. The study shows progressive enhancement in the biodegradation of effectively non-biodegradable polypropylene with an increase in degree of acrylic acid grafting. The methods presented here can be used for the design and control of other similar systems.