No abstract

This research focuses on the impact of adding materials such as carbon black and polymer of carboxyl methylcellulose on the the rheological properties of styrene butadiene rubber (SBR) and natural rubber (NR) which was studied as a matrix. The present study was a carried out by two groups according to the loading level of carboxyl methylcellulose (CMC) and carbon black(C.B) its molecular weight (N660) which their used as stiffeners in the composites. on the other side, rheometer tests carried according to ASTM D 2705 For the purpose use these composites in various tire making and fender ship. All composites are consisting of carbon black (C.B) N660 (0, 10, 10, 10, 10) pphr and carboxyl methyl cellulose (CMC) (0, 0, 10, 20, 30) pphr respectively for the first group (A) and (0, 20, 20, 20, 20) pphr for C.B, (0, 0, 10, 20, 30) pphr for CMC for the second group (B). The maximum torque, minimum torque, scorch time, viscosity and Tc90 optimum curing time were checked. The results revealed that the parameters differ according to the level of loading. Viscosity, lower torque, maximum torque and optimal curing were reduced for increasing loading ratio of the C.B and CMC. As well, an optimal curing time of the TC90 burning time was reduced as addition ratios of the carbon black (C.B) and carboxyl methyl cellulose (CMC) increased.

In this present study, polymer blend (PVA-PVP)-Carbon black (C. B N375) nanocomposites have been investigated. The (PVA-PVP-C. B) nanocomposites are organized by via casting procedure. The optical microscope, FTIR and electrical properties have been studied. The constant of dielectric with the dielectric loss of the samples were reduced with increasing the value of frequency during the application of electric field, while an increasing in the A. C electrical conductivity results existed with the rising the value of the frequency. The electrical conductivity (A. C), dielectric loss and constant of all the samples were increased with the increasing of the carbon black concentrations.

In this study, prepared nano-composite materials to absorption and sensing harmful waves for human health, it made of polyester were prepared with a fixation hardener ratio of 0.1 g per 10 ml of polyester. This percentage was constant in all samples and addition of both chlorophyll(CLL) and lead oxide (PbO<100nm) as well as lead oxide with chlorophyll by weight percentage (0.2,0.5, 0.2 (CLL) with 0.5(PbO)wt.% receptivity, then study coefficient of loss of reflectivity of all samples where the results indicated that most prepared materials correct for use attenuation materials of microwaves where is the reflection coefficient of all samples larger than (10dB) this show that absorption of composite materials consistence larger than 90%, then study reflection coefficient and also definition complex permittivity in the range frequencies (3-5)GHz were observed that value of the complex permittivity larger than one(μR > 1).

This research includes preparation (NR50/SBR50/Oyster Shell Powder OSP) composites while the loading ratio of OSP were 0, 5, 10, 15, 20, 25, 30, 40, 60, 80, 100 pphr. The examination of FTIR (Fourier Transform Infrared analysis) of some specimen composites were carried out and study the effect of calcium carbonate (Oyster Shell Powder OSP) grain size <225 μ on the rheological properties of (NR50/SBR50/OSP) composites with different loading ratio of (OSP). The device used to examine the characteristics is oscillating disc rheometer according ASTM D-2705 and temperature 185°C, pressure 10 bar and time 6 min. These rheological properties included the scorch time (ts2), cure time (tc90), viscosity, Maximum torque (MH), Minimum torque (ML) while the results of all these properties were decreasing with increase the loading ratio of OSP with or without C.B 10 pphr also all these properties were decreasing after addition C.B = 10 pphr for the same loading ratio of OSP except maximum and minimum torque at high loading ratio.