The present researchers are trying to enhance the properties of paper sheet that used widely in many fields such as printing and packaging. The enhancement of paper quality is also possible to preserve paper documents of all kinds, as they are the true record, full of the history, achievements of the human being and the intellectual and cultural of the country. It is possible to improve its physical and mechanical properties and preserve them from damage through the use of some solutions of polymeric adhesives, which act as protective barriers against water and moisture penetration. The paper also has the advantage of porosity, which has been overcome by using three types of polymeric adhesives (Nitro Cellulose, Polyvinyl alcohol acetate, and Poly methyl methacrylate, as it formed a transparent layer, that led to an increase in thickness, hardness, ability to withstand folding and tensile, and a decrease in the intensity of brightness, as polymeric solutions showed their superiority in resisting moisture.
In this paper we investigate how do the laminated composites behave mechanically when subjected to external stresses, when reinforced with continuous fibers (mat) and discontinuous fibers (chopped) and to find the effect of the fiber type on the mechanical properties. Laminated composites consisting of wood- wood and Ph-F resin as suitable adhesive were reinforced with different fibers(jute, glass, and carbon).However, two different methods of reinforcement namely, mat and chopped fibers were utilized. The mechanical properties such as (impact strength, compression strength, tensile strength, shear strength, bending strength, and elasticity modulus) of laminated composites were measured. Fibers reinforced laminated composite
... Show MoreIn this work, a composite material was prepared from Low-density polyethylene (LDPE) with different weight percent of grain and calcinations kaolin at temperature of (850oC) using single screw extruder and a mixing machine operated at a temperature between (190-200oC). Some of mechanical and physical properties such as tensile strength, tensile strength at break, Young modulus, and elongation at break, shore hardness and water absorption were determined at different weight fraction of filler (0, 2, 7, 10 and 15%). It was found that the addition of filler increases the modulus of elasticity, elongation at break, shore hardness and impact strength; on other hand, it decreases the tensile strength and tensile strength
... Show MoreUnsaturated polyester was used as a matrix which was filled with different percentages of cobalt ferrite using hand lay-up method. Cobalt ferrite was synthesized using solid state ceramic method with reagent of CoO and Fe2O3. Mechanical properties such tensile strength, Young's modulus and shore D hardness of the composite have been studied. All these properties have increased by 10% with increasing cobalt ferrite contents. Also the thermal properties such thermal conductivity and specific heat capacity are highly increased as the ferrite content increased, while the thermal diffusivity increased by 22 %. On the other hand dielectric strength of composite has been measured which increased by 50% by increasing the cobalt ferrite content.&
... Show MoreObjective(s): In the present study, glycerin is used as a substitute for tin-foil and cold mold seal (Alginate mould seal)
in the process of curing heat and cold-cure acrylic resin denture base against stone and plaster.
Methodology: 60 specimens were prepared from heat-cure acrylic resin and cold-cure acrylic resin denture base. The
study includes 12 groups of specimens depending on the type of processing, investment material and type of
separating medium that are used in curing process. Each group of them contains 5 specimens for each test.
Some of physical properties of the processed acrylic denture base that (water sorption and solubility) have been
compared with those processed using tin-foil and tin-foil substitut
In this paper, chip and powder copper are used as reinforcing phase in polyester matrix to form composites. Mechanical properties such as flexural strength and impact test of polymer reinforcement copper (powder and chip) were done, the maximum flexural strength for the polymer reinforcement with copper (powder and chip) are (85.13 Mpa) and (50.08 Mpa) respectively was obtained, while the maximum observation energy of the impact test for the polymer reinforcement with copper (powder and chip) are (0.85 J) and (0.4 J) respectively
The effect of micro-and nano silica particles (silica SiO2 (100 μm), Fused silica (12nm)) on some mechanical properties of epoxy resin was investigated (Young's modulus, Flexural strength). The micro-and nano composites were prepared by using three steps process with different volume fraction of micro-and nano particles (1, 2, 3, 4, 5, 7, 10, 15, and 20 vol. %). Flexural strength and Young's modulus of nano composites were increased at low volume fraction (max. enhancement at 4 vol.% ). However at higher volume fraction both Young's modulus and flexural strength decrease. Moreover, above, the mechanical properties are enhanced more than that of neat epoxy resin. The flexural strength decreases with increasing the volume fraction of micr
... Show MorePermanent deformation (rutting) of asphalt mixtures is one of the major forms of distress. Aggregate gradation is one of the most important factors affecting the permanent deformation of asphalt mixtures. Other variables are also important to understand their effects on the mixture such as temperature, binder content and compaction level. For this purpose 6 different aggregate gradations have been chosen and each one of them has been manufactured / tested with different variables. The results showed that at relatively low temperature there is little effect of aggregate packing on the permanent deformation. However, as the temperature increases the effect of gradation becomes apparent, in that the better the packing the better the resistance
... Show MoreThe densities and visconsities of solutions of poly(vinyl alcohol)(PVA) molccuar weight (14)kg.mol-1in water up to 0.035%mol.kg-1
Number of new polyester and polyamide are prepared as derivatives from 5,5`-(1,4-phenylene)-bis-(1,3,4-thiadiazole-2-amine) [C1], three series of heterocyclic compounds were synthesized.The first series includes the Schiff base [C2] prepared from the reaction between compound [C1] with p-hydroxy benzaldehyde in presence of acetic acid and absolute ethanol , then these derivatives have reaction with maleic anhydride , phthalic anhydride and sodium azide, respectively to obtain the compounds [C3-5] contaning (oxazepine and tetrazole) rings.The third series of compounds [C1-5] has transformed to their polymers [C6-15] by reaction with adipoyl chloride and glutroyl chloride , respectively. The reaction was followed by T.L.C and ident
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