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In water industry, the chlorine is mostly used as a disinfectant agent. The chlorine present in potable water as a disinfectant has been reported to reduce the lifetime of contact polymeric material. This occurs in polymer pipes and it is now very common in plumbing and other parts of the drinking water distribution system. For more than 50 years, Polymer & Elastomeric materials have been used ubiquitously in drinking water distribution systems. Polymer & Elastomeric materials have successfully been used in a variety of applications ranging from rubber gaskets, to valves, to hydrants, to fittings. Polymer & Elastomers that degrade more quickly than expected create service problems, make it difficult for utilities to cost efficient plan preventive maintenance programs, and negatively affect customer relations. This review paper gives an insight idea to a reader about the selection of proper polymer & elastomer and predicting its performance in chlorinated water. Also the mechanism of degradation of Polymer & elastomer in chlorine environment and some model of life expectancy of in-service of Polymer & elastomer in various conditions and parameter in chlorinated water were discussed.

Plastics have become an inseparable part of our life in the society due to their merits such as low cost, light weight, good mechanical and thermal properties along with easy process ability. Since the last few decades, the unrestrained use of plastics in various fields like agriculture, packaging, transportation has raised a serious issue about its disposal and pollution. An efficient decomposition of plastics takes about 1000 years. Not only there is an increase in the problem of waste disposal of plastics but also they release CO2 and dioxins on burning which contributes to cause pollution. There is a growing concern for use of efficient microorganisms meant for biodegradation of non-degradable synthetic polymer because conventionally used methods for plastic disposal are ineffective for plastic waste management. This review paper focuses on one such type of plastic-polyethylene terephthalate (PET) which is widely used in a flexible packaging application, its manufacturing process and the various effects of waste generated by it on the surrounding environment. This review discusses an overview of various existing plastic disposal methods along with their limitations and mechanism of biodegradation of PET and factors affecting biodegradation.

The objective of this study was to investigate the effects of two elastomers, namely ethylene butene copolymer (EBC) and ethylene propylene diene monomer (EPDM), on the physical, thermal and morphological properties of blend after exposure to chlorine. Blends of linear low-density polyethylene (LLDPE), ethylene-butene copolymers (EBC) and ethylene propylene diene ter polymer (EPDM) with different content were prepared by melt mixing in a twin-screw extruder. The LLDPE blend with EBC and EPDM were tested with water containing 50 ppm and 5000 ppm chlorine under static condition for 500 hr at 25°C and 80°C. Highest weight gain was observed for a higher concentration of chlorine for LLDPE/EBC-55 and LLDPE/EPDM-37 blend. It is seen that at 50 ppm chlorine concentration, the mechanical properties of LLDPE, LLDPE/EBC blend and LLDPE/EPDM blend remain unchanged. Chemical changes in the aged sample were checked by Infrared spectroscopy (FTIR), where increase in the O-H and C=O infrared bands was observed. The thermal characteristics of LLDPE, LLDPE/EBC blend, and LLDPE/EPDM blends were investigated using DSC and TGA which shows melting temperature and crystalline melt temperature remains unchanged while percent crystallinity was increased by 10 percent for LLDPE. Scanning electron microscope (SEM) showed that there was no formation of the micro cracks and cavities of LLDPE/EBC 73 blend and LLDPE/EPDM 73 blend after exposure to a higher concentration of chlorine. It indicated the excellent stability of prepared blend against chlorinated water

In this work, the synergistic effect of the γ-ray irradiation and catalyst on the pyrolysis of High-Density Polyethylene (HDPE) waste was investigated in a batch reactor. Two catalysts, Zeolite Socony Mobil–5 (ZSM-5) and Ferric oxide, were used, and their loading was optimized. The results revealed that the degradation temperature significantly reduced with increasing dosage of irradiation. The complete pyrolysis of HDPE waste occurs at a temperature of 400°C and reaction time of 240 min (4 h), while in a case of irradiation-induced pyrolysis, there is higher yield and decrease in the residence time of pyrolysis. Irradiation with a higher dosage (2,000 kGy) increases the rate of thermo-catalytic pyrolysis for HDPE waste and gives maximum conversion.

The free chlorine present in water which is used as a disinfectant is reported to reduce the life of the polymeric material. The objective of this work is to study the influence of chlorine concentration on low-density polyethylene (LDPE) and blends of LDPE with ethylene butene copolymer (EBC) and ethylene propylene diene terpolymer (EPDM). The LDPE blend with EBC and EPDM were tested with water containing 50, 500, and 5000 ppm chlorine under static condition for 500 h at 25 and 80 °C. It has been seen that at 5000 ppm chlorine concentration, the mechanical properties of LDPE, LDPE/EBC blend, and LDPE/EPDM blend changed drastically and a significant reduction in the elongation at break was found for LDPE, LDPE/EBC, and LDPE/EPDM blend. LDPE/EPDM shows stable modulus value for 5000 ppm as 80 °C. Chemical changes in the aged sample were studied by Fourier transform infrared spectroscopy (FTIR) where an increase in the O–H and C=O peaks were observed. The thermal characteristics of LDPE, LDPE/EBC blend, and LDPE/EPDM blends were investigated using DSC and TGA which shows that the melting temperature and crystalline melt temperature remains unchanged while percent crystallinity increases slightly. Scanning electron microscope showed that there was the formation of microcracks and cavities on the fracture surface of LDPE, LDPE/EBC blend, and LDPE/EPDM blend after exposure to a higher concentration of chlorine indicative of degradation. Furthermore, the Chlorine resistance of LDPE/EPDM blend at 5000 ppm chlorine concentration is much higher than that of pristine LDPE.

Layered double hydroxides (abbreviated as LDHs) are one of the nanoordered layered compounds. The importance of layered compound is based on their ability to retain chemical species with electrical charges compatible to those of the layers. In this study we have reported the synthesis of nanosized layered double hydroxide (LDH) by co-precipitation method using two different surfactants as cetyl trimethyl ammonium bromide (CTAB) and octadecyl trimethyl ammonium bromide (ODTMA) having different critical micelle concentration (CMC) /chain length and its comparative results on calcined surface modified LDH (CS-LDH). The structure of surface modified layered double hydroxide (CS-LDH) synthesized is unique and has important advantages to the photocatalytic activity. LDH has significant number of application due to their structural, chemical properties etc., these compounds can be used as catalyst, adsorbents, anion exchanger. The photocatalytic activity of prepared surface modified CS-LDH was tested on degradation of the methylene blue (MB) dye in an aqueous solution. The surface characteristics of LDH and CS-LDH were examined using Energy Dispersive X-ray (EDX), Scanning Electron Microscopy (SEM), X-ray diffraction (XRD) and UV-Visible spectrophotometer for Photocatalytic activity under visible light using MB dye. It was observed that highly exfoliated and basal spacing in CS-LDH-ODTMA which enhanced photocatalytic activity (Approx. 60% degradation) than that of comparison to CS-LDH-CTAB (Approx. 32% degradation).

Summary Any material consisting of two or more components with different properties and distinct boundaries between their components can be referred to as a composite material. There are two groups of composites the first group comprises composites that are known as “filled materials”, the main feature of these materials is the existence of some basic or matrix material whose properties are improved by filling it with some particles and second group composites involves so called “reinforced materials”. The basic components of these materials are long and thin fibres possessing high strength and stiffness. Filler (particulate or thin fibers) is a solid material capable of changing the physical and chemical properties of materials by surface interaction or its lack thereof and by its own physical characteristics. High stiffness means that material exhibits low deformation under loading. Stiffness is an important property but it should be necessarily high. Ability of structure to have controlled deformation can be also important. Nano engineered polymeric materials are of great interest, rapidly growing new class of materials alternative to conventional filled polymers or polymer blends. Conventional clay plays the role of a loading agent or diluent without property enhancement or reinforcement and hence we have used nanoclay which imparts significant mechanical reinforcement and improved air permeability property for natural rubber based tube compound. Natural rubber/nanoclay along with other additives were mixed in a laboratory mixer for specified time and temperature, by determining rheological and curing properties rubber compounds were molded in to standard dimension sheets using a compression mold and molding machine thereafter specimens were prepared and characterized for hardness, modulus (100%, 200%), tensile strength, tension set, air permeability test and surface morphology.

Serials of polystyrene/SiO2 Nano composites (PS/SiO2) with different content of inorganic fillers were successfully prepared by the in situ bulk radical polymerization of styrene under microwave irradiation. The effect of the amount of Nano SiO2 on the properties of the PS/SiO2 Nanocomposites along with the average relative molecular masses (Mn, Mz and Mw) was investigated by thermal analysis and X-Ray Diffraction (XRD). Their structural model was proposed on the basis of the Optical Microscopy, FTIR (Fourier Transform Infrared) analysis, differential scanning calorimetry (DSC), gel permeation chromatography (GPC) and X-Ray Diffraction (XRD). The dispersion of nanoparticles in Polystyrene is observed in the magnified image. The effect of microwave irradiation power on molecular weight of polystyrene was also studied. It was found that, the microwave assisted reaction needs less time as compare to conventional polymerization and found to be in between 10 to 15 min.

Rigid and plasticized PVC is used extensively in a variety of industries like construction, packaging sheet and film, electrical, automotive parts, furniture equipment, clothing, footwear, etc. In recent years, natural biobased materials are being explored for plasticizers for PVC. The present work focuses on the development of different epoxidized soybean oil (ESBO) plasticized PVC formulations in the presence of calcium/zinc stearates and beta-diketone stabilizer such as dibenzoylmethane (DBM). The DBM which has dual property of a UV stabilizer and heat stabilizer was varied from 0 to 10 phr. The PVC films were prepared and analyzed in terms of dehydrochlorination studies. The above PVC films were exposed for 100 h in the accelerated QUV weathering, and the characterization of the exposed products was carried out in terms of mechanical and thermal properties and dehydrochlorination. This ternary system hinders the degradation process and decreases the initial rate of dehydrochlorination. The success of the novel beta-diketones stabilizers can meet higher performance and longer service life of epoxidized soybean oil plasticized PVC films in the presence of zinc/calcium stearates. This will ultimately lead to a positive influence on the environment.

The science and technology of synthetic polymers has undergone explosive growth in the last few decades and the number of different polymeric materials in our built environment increases almost daily. All organic polymers burn and thus entail some measure of fire hazard in some situations. With increasing awareness of the nation’s fire problem it has become evident that the problems associated with flammability of polymeric materials must be attacked and solved. With the large number of polymers in commercial use. Problems of flammability and fire retardation are complex and multifaceted properties have to be developed, or existing polymers must be modified by addition of fire-retardant compounds. EPDM Rubber has many attractive properties such as low shrinkage, ease of cure and processing, excellent moisture, solvent and chemical resistance, good mechanical and electrical properties, as well as ease of modification to optimize the properties. However flammability is a major limitation in area requiring high flame resistance. Aluminum trihydroxide (ATH) due to its flame retardancy property is widely used as non reinforcing filler in wires and cable compound along with silica and carbon black. In this study carbon black is fully replaced by nano ATH to make environment friendly rubber products. However, the dispersion of nano particles in rubber is remarkably poor and hence techniques like melt mixing, solution mixing and master batching of nano ATH with EVA (Ethylene- vinyl acetate) are used to improve the dispersion of nano ATH particles in EPDM elastomers. In the current study we have used melt mixing for improving the dispersion of nano ATH and excellent results were obtained with optimum loading of nano ATH.

Polyurethane has high mechanical properties. This chapter deals with the basic concepts of mechanical properties and dynamic mechanical properties. The dynamic mechanical properties are dependent on the temperature and structure of the materials. The chapter details the dynamic mechanical properties of polyurethane and its blends with different polymers. Both thermoset blends and thermoplastic blends are discussed. When coming to interpenetrating networks, the importance of the mechanical analysis is increased.

The melt rheology of polypropylene (PP) filled with fly ash (FA) before and after treatment with coconut water (CW) was studied for different concentration of the filler. The fly ash after coconut water treatment clearly showed additional peaks in the infrared (IR) spectra corresponding to the hydroxyl and carbonyl groups indicating good adsorption of CW on FA. The X-ray diffraction of melt compounded PP filled with CW-treated (CWT) FA showed large reduction of the main silica peak of FA and considerable broadening of Mullite and hematite peaks suggesting formation of fine particles by this treatment. Scanning electron microscopy (SEM) confirmed the drastic reduction of particle size in these composites. The melt rheological studies for these composites indicated considerable increase in viscosity at low filler loading for CW treated FA. The concentration dependence of melt viscosity did not follow any of the theoretical equations suggested in literature. Although, the behavior was similar to nanoparticle-filled polymers, there were some differences especially above the critical concentration of 4.5% by volume. The frequency dependence of storage and loss modulus indicated crossover point clearly, which was greatly affected by CW treatment. The Cole–Cole plots of real and imaginary part of melt viscosity brought out the broad distribution of relaxation time for the CW treated FA. The CW treated FA melt compounded with PP gave rise to nanocomposites with uniform dispersion. However, above 4.5% by volume, there appears to be agglomerate formation along with a thin interfacial layer, which assists the melt flow even at high filler loading. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43900.