ABSTRACT

This research aims to study the effect of addition novolac material (phenol formaldehyde resin, polar) on the mechanical and physical properties of nitrile rubber (NBR) and the proportion of addition novolac material is(0,10,20,30,40,50 pphr) to a sample of nitrile rubber containing 40 part per hundred rubber (pphr) carbon black as a proportion stationary been prepared with (factors of vulcanization, accelerators and activators using two-roll mill laboratory, molds, thermal piston and difference of examination conditions from pressure, temperature and time according to the ASTM), all tests were conducted in the laboratories of the college of materials engineering-university of babylon and laboratories of babylon tire company. Then carrying out the process of scheduling the results of laboratory testing and study its diagrams. Where the results showed the mechanical properties increase in hardness, modulus of elasticity, and resistance to compression, and improved a little in the tear resistance, especially when the amount of novolac are 10 and 20 pphr, and a decrease in properties (tensile strength, elongation at break and resilience), also results show increase in adhesion with polyester fibers and nylon fibers when increasing novolac material. While the results of the physical properties show primitive increase in viscosity, the greatest torque twisting, scorch time and cure time, then decrease for to increasing novolac material. specific gravity also increases with increasing novolac material.

This paper explains the successful and simple process of generating a rubber mount with novel properties by incorporating carbon black particles type ISAF 220 at different ratios ([46, 56, 66, 76, 86] [pphr]). Rubber mounting was made using 100 % natural rubber and carbon powder that was applied to the master batch ratio (60 g). To achieve greater homogeneity, rubber and carbon were combined for several minutes. The rubber mount has been subjected to several tests at Babylon tires factory and Babylon University (tensile, elongation, modulus, compression, hardness, rebound resilience, specific gravity and fatigue tests). The best results were obtained from the rubber mount, as it had the ability to resist fatigue and could be used for a long period of time. It could also increase the number of cycles to 900 rpm. The rubber mount that was reinforced with carbon had a better resistance to the mechanical properties (tensile, hardness, fatigue and resilience). The results of the tensile strength, hardness, fatigue and resilience tests showed that additional quantities of carbon at 66 pphr increased the values by up to 18.95 Mpa, 64 Mpa, 600 Mpa and 55.5 Mpa, respectively.

Shape memory polymers and their related composites are formally known as SMPs and SMPCs have been classified as innovative categories of smart materials, in which they affected by a particular stimulus and consequently memorize the original shape. As one of the most vital feature of shape memory characteristics, Shape Memory Effect (SME) that been attracted significant attention from the shape memory researchers and scientists. On the other hands, there are abundant approaches can be implemented to actuate the SMPs and SMPCs deformation, whereby the features of the electro-or thermal response associated with the structural changes are predominant. In this chapter, a particular emphasis on how the incorporation of micro/nano-fillers and particles or fibers do affect in the SMP matrices, which it is intentionally carried out to improve the mechanical properties and their related shape memory features of various types of shape memory polymers. In the summary, the shape memory effect is been sustained to be an intrinsic feature for the SMPs and based on this property, the implementation of the SMPs have covered a wide range of applications according to the required functions and performances.

In this article, novolac nanoparticles with different weight fraction (0-40) wt.% were added to NBR/CR blends and investigate the effect of these additions on the specific gravity of rubber blend. The results obtained shown that the novolac nanoparticles works on increasing the specific gravity of NBR/CR blends, and specific gravity ratio increases with increased novolac nanoparticles percentage.

Polymethylmethacrylate is considered the most prevalent bone cement base material. Most fractures that occur during function are due to its weakness and lack of mechanical strength. The apparent limitations of PMMA are insufficient ductility, strength, and viscoelastic behavior. The current study aims to strengthen and improve PMMA bone cement properties by adding modified TiO2 nanoparticles (m-TiO2 NPs). Therefore, the silane coupling agent modified the neat TiO2 NPs and then added different ratios (0.5, 1, 1.5, and 2 wt %) to the PMMA bone cement. Fourier transform infrared spectroscopy (FTIR) technique used to investigate the modification process and specify the bonding type between m-TiO2NPs and the PMMA bone cement matrix. The SEM technique is used to study the morphologies of the prepared samples. Properties such as tensile strength, compression strength, modulus of elasticity, and impact strength, were measured. Results proved the successes of TiO2NPs modification by silane coupling agent and the absence of any chemical bonding between this modified filler and other PMMA bone cement ingredients. The mechanical properties increased by m-TiO2NPs addition up to 1 wt% ratio then decreased. The morphology results supported the mechanical properties trends.

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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).