Effects of (conductive polypyrrole)‐modified tire dust on the mechanical,electrical, and morphology properties of (low‐density polyethylene)/(tire dust) composites

The effects of conductive polypyrrole (PPy) as a coupling agent on the mechanical properties, morphology, electrical properties, and thermal degradation of (low‐density polyethylene)/(tire dust) (LDPE/TD) composites were studied. LDPE/TD composites with different TD loadings and added PPy were prepared with a Brabender Plasticorder. The LDPE/TD_T (treated with PPy) composites showed higher values of tensile strength, modulus of elasticity, electrical conductivity, thermal stability, and swelling resistance than LDPE/TD composites. Scanning electron microscopy morphology revealed that the interfacial adhesion between the TD and LDPE phases was improved by the addition of conductive PPy. J. VINYL ADDIT. TECHNOL., 20:131–136, 2014. © 2014 Society of Plastics Engineers     

Effect of Polyethylene-Grafted Maleic Anhydride (PE-g-MAH) on Properties of Low Density Polyethylene/Eggshell Powder (LDPE/ESP) Composites

The effect of polyethylene-grafted maleic anhydride (PE-g-MAH) on the tensile properties, morphology and thermal properties of low-density polyethylene (LDPE)/eggshell powder (ESP) composites was studied. LDPE/ESP composites with different eggshell powder content and the addition of PE-g-MAH were prepared with Z-blade mixer at 180°C and rotor speed of 50 rpm. The tensile strength, elongation at break and thermal stability of LDPE/ESP composites with PE-g-MAH were greater than LDPE/ESP composites, and their differences became more pronounced at higher filler content. The interfacial adhesion between ESP and LDPE was improved with the addition of PE-g-MAH as evidenced by the morphological study.     

Effect of Vinyl Alcohol-Phthalic Anhydride on Properties of Low Density Polyethylene (LDPE)/Tyre Dust (TD) Composites

The effect of vinyl alcohol-phthalic anhydride as a coupling agent on the tensile properties, morphology, and thermal degradation of low density polyethylene/tyre dust (LDPE/TD) composites was studied. LDPE/TD composites with different tyre dust loading and the addition of vinyl alcohol-phthalic anhydride were prepared with Z-blade mixer at 180°C and rotor speed of 50 rpm. The result indicated that LDPE/TD_M composites with vinyl alcohol-phthalic anhydride show higher values of tensile strength, Young's modulus and mass swell, but lower elongation at break than LDPE/TD composites without vinyl alcohol-phthalic anhydride. The SEM micrographs showed that the tyre dust was more widely dispersed in the LDPE matrix with the addition of vinyl alcohol-phthalic anhydride as a coupling agent. It was also found that the addition of vinyl alcohol-phthalic anhydride offers better thermal stability in the LDPE/TD_M composites than LDPE/TD composites.     

Effect of Poly(methyl Methacrylate) Modified Water Hyacinth Fiber on Properties of Low Density Polyethylene/Natural Rubber/Water Hyacinth Fiber Composites

The effect of poly(methyl methacrylate) modified water hyacinth fiber on properties of low density polyethylene (LDPE)/natural rubber (NR)/water hyacinth fiber (WHF) composites were investigated. The composites were prepared with Z-blade mixer at 180°C and rotor speed of 50 rpm. The poly(methyl methacrylate) modified water hyacinth fibers in LDPE/NR composites (LDPE/NR/WHF-_PMMA) gave a greater value of tensile strength, Young's modulus, glass transition temperature (Tg), melting temperature (Tm), and % crystallinity compared to unmodified water hyacinth fibers in LDPE/NR composites (LDPE/NR/WHF). FTIR analysis shows the presence of ester carbonyl group and C-O ester group in poly (methyl methacrylate) modified water hyacinth fiber. The SEM micrograph also shows a better interfacial adhesion between the fibers and LDPE/NR matrixes for LDPE/NR/WHF-_PMMA composites than LDPE/NR/WHF composites. LDPE/NR/WHF-_PMMA composites had a lower value of interparticle spacing compared to LDPE/NR/WHF composites thatenhanced the interparticle interaction between fiber and LDPE/NR matrixes.     

Characterizations and electrical conductivity of (poly[vinyl chloride])/(poly[ethylene oxide]) conductive films: The effect of carbon black loading and poly(ethylene glycol) diglycidyl ether

The effect of carbon black (CB) loading filled (poly[vinyl chloride])/(poly[(ethylene oxide]) (PVC/PEO) conductive films with and without poly(ethylene glycol) diglycidyl ether (PEGDE) was studied. The PVC/PEO/CB and PVC/PEO/PEGDE/CB conductive films were prepared by a solution casting method. The results indicate that the addition of PEGDE of PVC/PEO/CB/PEGDE conductive films exhibited higher tensile properties, electrical conductivity, and thermal stability compared with PVC/PEO/CB conductive films. The scanning electron microscope micrographs of PVC/PEO/PEGDE/CB conductive films showed a rough surface and a good distribution of CB on the surface of PVC/PEO/CB conductive films. Fourier‐transform infrared spectrum showed that the interaction between the PVC/PEO films and the CB‐PEGDE phase on the surface of the conductive films does not change the functional group of the PVC/PEO/PEDGE/CB conductive films. J. VINYL ADDIT. TECHNOL., 24:139–146, 2018. © 2016 Society of Plastics Engineers     

Geophysical investigations of the Wairakei Field

Geophysical studies of the Wairakei sector of the Wairakei–Tauhara geothermal system started shortly after exploration drilling began in the early 1950s. These investigations have made a major contribution in defining the boundary of geothermal systems and understanding the changes that have occurred in the reservoir as a result of fluid production. The most successful tools have been electrical resistivity methods for delineating the field, while microgravity, heat loss and groundwater level monitoring surveys were useful to interpret production-induced changes. Seismic, gravity and magnetic surveys had only limited success.     

Effects of sodium hydroxide treatment on the properties of low‐density polyethylene composites filled with chicken feather fiber

The effects of alkali treatment with sodium hydroxide on the tensile properties, morphology, thermal degradation, and mass swell of low‐density polyethylene (LDPE)/(chicken feather fibers (CFF)) composites were studied. The LDPE/CFF composites were prepared by using a Z‐Blade mixer at 180^oC and a rotor speed of 50 rpm. The LDPE/CFF‐_Treated composites exhibited higher tensile strength, Young's modulus, and final decomposition temperature but had lower mass swell percentage and elongation at break than the LDPE/CFF composites. An SEM morphology study showed that the CFF treatment could significantly improve adhesion at the interface and lead to ingress of the fiber into the LDPE phase. Thermogravimetric analysis indicated that the LDPE/CFF‐_Treated composites had higher thermal stability than the LDPE/CFF composites. J. VINYL ADDIT. TECHNOL., 20:36–41, 2014. © 2014 Society of Plastics Engineers     

Interpretation of magnetic anomalies over the Waimangu geothermal area, Taupo volcanic zone, New Zealand

The study area is located on the eastern side of the Taupo volcanic zone in central North Island of New Zealand. It lies a few kilometres to the southwest of Mt Tarawera, the site of the biggest New Zealand volcanic eruption in historical times (the June 1886 Tarawera eruption). The study area includes the Waimangu geothermal field and a small part of Waiotapu and Waikite fields. The extensive surface thermal expressions (boiling springs, hot lakes, craters, and sinter terraces) occurring at the Waimangu field were all formed following the 1886 Tarawera eruption. Another large area of less intense thermal manifestations (thermal ground and hydrothermally altered rocks) exists about 5 km southwest of Waimangu, extending towards the Waiotapu field in the south. In 1993 an aeromagnetic survey was conducted over the study area at an average altitude of about 350 m above the ground. The results show a subdued negative residual anomaly (about −100 nT) over the Waimangu field, which can be interpreted by near-surface hydrothermal demagnetisation of rhyolitic host rocks. The lateral distribution of the demagnetised rocks is much greater than the thermal area of Waimangu, and is consistent with the extent of low resistivity rocks across the study area. The magnetic interpretation also shows that two-high standing dacite domes situated about 5 and 7 km to the southwest of Waimangu have been affected by hydrothermal demagnetisation. There are negative residual anomalies outside the low resistivity zone that could be associated with reversely magnetised rocks (age >0.78 Ma). A strong positive residual anomaly (up to 450 nT) occurs to the east of the Waimangu field. Results from 3-D magnetic interpretation indicate some alternative models for this positive anomaly: (1) southwest–northeast trending, vertical basalt dykes (magnetisation 10 A/m), tops between −0.1 and −0.65 km RL (reduced LEVEL=relative to sea level), (2) a thick ( 1 km) sequence of rhyolites (magnetisation 2.5 A/m) extending from the surface down to about −0.8 km RL, and (3) a rather thin (0.35 km) sequence of rhyolites (from surface to sea level) underlain by basalt bodies similar to those of model (1).     

Effects of Dynamic Vulcanization and Acrylic Acid on Properties of Recycled Poly(vinyl chloride)/Acrylonitrile Butadiene Rubber (PVCr/NBR) Blends

Effects of dynamic vulcanization and acrylic acid (AAc) on processability, mechanical properties, swelling behavior, morphology, and thermal stability of recycled poly(vinyl chloride)/acrylonitrile butadiene rubber (PVCr/NBR) blends were investigated. Blends were prepared in a Haake Rheomix at a temperature of 150°C and a rotor speed of 50 rpm. Recycled poly(vinyl chloride)/acrylonitrile butadiene rubber (PVCr/NBR) blends were also prepared as comparison. It was found that the dynamic vulcanization and the addition of acrylic acid improved the stabilization torque, mechanical energy, stress at peak, stress at 100% elongation (M₁₀₀), swelling resistance, and thermal stability but decreased the elongation at break of the blends. The introduction of a cross-link into the elastomer phase and better compatibility between PVCr and NBR are responsible for the enhancement of thermal stability and mechanical properties of dynamically vulcanized PVCr/NBR + AAc as evidence from the scanning electron microscopy (SEM) of the tensile fracture surfaces and infrared spectroscopy study of the dynamically vulcanized of PVCr/NBR + AAc shows.