shahram Badamchi; Ahmad Jahan latibari; Mehran Rohnia; Seid Javad Sepideh dam
Abstract
In this research the effect of softwood cellulose fibers surface characteristics on mechanical properties of cellulose fibers / polypropylene composite (W.P.C) was studied. The fibers were refined to modify the surface characteristics and reach four different freeness levels (11, 14, 17 and 21 °SR). ...
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In this research the effect of softwood cellulose fibers surface characteristics on mechanical properties of cellulose fibers / polypropylene composite (W.P.C) was studied. The fibers were refined to modify the surface characteristics and reach four different freeness levels (11, 14, 17 and 21 °SR). Then the fibers were mixed with polypropylene using pre-determined levels of 20% fibers and 77% polypropylene and 3% MAPP and samples were made. The results revealed that refining the fibers will change the strength of the composites. Statistical analysis should that the impact of the different freeness levels statistically influenced the strength at 99% confidence level. The highest strength levels were reached using fibers with the freeness level of 14 oSR.
Ahmad Jahan latibari; Reza Jamail; Mehran Roohnia
Abstract
The influence of different dosages of surfactant and soap in the deinking of wastepaper is investigated. The results showed that the dosage of 0.25% soap generated highest brightness and lowest opacity. However, the dosage of 0.75% soap produced highest tensile and burst strength and 0.5% soap produced ...
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The influence of different dosages of surfactant and soap in the deinking of wastepaper is investigated. The results showed that the dosage of 0.25% soap generated highest brightness and lowest opacity. However, the dosage of 0.75% soap produced highest tensile and burst strength and 0.5% soap produced the lowest spec (dirt) index. In the case of surfactant application, the dosage of 0.75% surfactant produced highest brightness and 0.5% surfactant generated lowest opacity. Application of 0.5% surfactant showed highest tensile and burst strength and lowest dirt index. The combined effect of both chemicals showed that the combined dosage of 0.75% surfactant and 0.25% soap produces highest brightness but the dosage of 0.25% surfactant without soap produced lowest opacity. Highest tensile and burst strength was related to pulp deinked using 0.5% surfactant and 0.75% soap. The results indicated that the combination of 0.75% surfactant and 0.25% soap generated highest brightness which the important property of the writing and printing paper. The highest tensile and burst strength was measured in deinked pulp produced using 0.5% surfactant and 0.75% soap.
Hanieh Ghasemi; Ahmad Jahan latibary; Mehran Rohnya; Mostafa Kohan torabi
Abstract
The effect of the application of different contents of canola particles in the production of particleboard on its acoustic properties were determined using free vibration on free-free bars procedure. 33 samples from each combination of canola and wood particles were prepared and the acoustical properties ...
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The effect of the application of different contents of canola particles in the production of particleboard on its acoustic properties were determined using free vibration on free-free bars procedure. 33 samples from each combination of canola and wood particles were prepared and the acoustical properties were determined. Results showed that as the content of canola particles in the mixture of the particles increases, the modulus of elasticity and acoustic coefficient of boards increases from 1260 MPa and 2.34 m4/s.kg to 1560 MPa and 2.54 m4/s.kg respectively. At the lower content of canola particles in the particles mixture, because of inhomogeneity, damping factor increased but by increasing the content of canola particles more homogeneous boards was obtained and damping factor decreased. Also, results showed that significant increase in acoustic coefficient efficiency was reached by increasing the content of canola particles. Therefore as the results revealed, incorporating more canola particles in the particleboard mixture, acoustic properties of particleboard improves and the product can be used in acoustic environments, halls and etc.
Porya Rezaei niaraki; Ahmad Jahan Latibari; Azhang Tajadini; Mehran Roohnia
Abstract
The influence of fiber lignin content and the dosage of coupling agent on the strength and physical properties of cellulosic fiber-polypropylene composite were investigated. The old corrugated container (OCC) fibers were delignified using sodium hydroxide to reach the lignin content of 2.7, 3.78, 5.26 ...
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The influence of fiber lignin content and the dosage of coupling agent on the strength and physical properties of cellulosic fiber-polypropylene composite were investigated. The old corrugated container (OCC) fibers were delignified using sodium hydroxide to reach the lignin content of 2.7, 3.78, 5.26 and 7%. Fibers were compounded with polypropylene by extrusion process using 20% fibers and 77% PP and the extrudate was cooled and grinded to fine granulates before injection molding. MAPP coupling agent was applied at three different levels (1, 2 and 3 percent based on the total weight of the composite). The strength properties of the composites were measured using relevant ASTM test methods and the results were statistically analyzed using factorial experiment under complete randomized design. The impact of fiber lignin content of flexural strength of composite was statistically significant at 98 percent significance level and the lowest and highest values of flexural strength of composite were measured at 3.78 percent and 7 percent lignin content of fiber. The interactive effect of fiber lignin and MAPP on the tensile strength and flexural modulus of elasticity of the composite showed that at lower values of lignin and higher dosage of MAPP, these properties are 38.7 and 3438 MPa respectively. Other strength values of the composites were also improved and at lower content of lignin and increaing dosages of the MAPP, the impact strength of the composites was increased from 52.82 J/m to 60.26 J/m.
