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polybutadiene
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High performance No-fines concrete using Styrene-butadiene latex
, Article Seventh International Conference on Damage and Fracture Mechanics: Damage and Fracture Mechanics VII, Maui, HI, 16 October 2002 through 18 October 2002 ; Volume 12 , 2003 , Pages 385-394 ; 14626055 (ISSN) ; Khalighi, Y ; Irajian, M ; Sharif University of Technology
2003
Abstract
No-fines concrete has considerable drainage property and a relatively low strength. A wide aggregate grading range, with higher percentage of aggregate in lower bound, improves strength properties, however such grading results in lower drainage capability. The objective of this paper is to make high-performance single-sized No-fines Concrete mixes using polymer modification. An experimental program was carried out to study the parameters of water-cement ratio, aggregate-cement ratio, type of polymer, polymer content, setting time and curing period. The test specimens were 6×12 in. cylinders and were cast using hand rodding compaction in accordance with ASTM C 31-69. Initially a proper...
Effects of fluid viscosity on a moving sonoluminescing bubble
, Article Physical Review E - Statistical, Nonlinear, and Soft Matter Physics ; Volume 84, Issue 2 , August , 2011 ; 15393755 (ISSN) ; Mirheydari, M ; Rezaee, N ; Ebrahimi, H ; Sharif University of Technology
2011
Abstract
Based on the quasi-adiabatic model, the parameters of the bubble interior for a moving single bubble sonoluminescence in water, adiponitrile, and N-methylformamide are calculated for various fluid viscosities. By using a complete form of the hydrodynamic force, the bubble trajectory is calculated for a moving single bubble sonoluminescence (m-SBSL). It is found that as the fluid viscosity increases, the unique circular path changes to an ellipsoidal and then linear form and along this incrementally increase of viscosity the light intensity increases. By using the Bremsstrahlung model to describe the bubble radiation, gradual increase of the viscosity results in brighter emissions. It is...
Synthesis of SBR/PMMA core/shell latices: the role of initiator and surfactant on particle morphology and instability performance
, Article Journal of Applied Polymer Science ; Volume 105, Issue 3 , 2007 , Pages 1412-1419 ; 00218995 (ISSN) ; Mohammadi, N ; Bagheri, R ; Sharif University of Technology
2007
Abstract
Poly(butadiene-stat-styrene)/poly(methylmetacrylate), SBR/PMMA, structural latices were synthesized by using equal moles of different kinds of surfactants: anionic, nonionic, and anionic/nonionic mixture in a two-stage emulsion polymerization. The results indicate that the application of anionic surfactants for the first stage, accompanying sodium persulfate initiator, KPS, for both stages led to core/shell and raspberry morphologies depended upon the hydrophilic lipophilic balance (HLB) of the surfactant. On the other hand, a core/shell structure was observed for structural latices which were synthesized via application of nonionic or anionic/non-ionic mixed surfactants along with...
Role of the nucleating agent masterbatch carrier resin in the nonisothermal crystallization kinetics of polypropylene
, Article Polymer Journal ; Volume 54, Issue 9 , 2022 , Pages 1127-1132 ; 00323896 (ISSN) ; Marouf, B. T ; Bagheri, R ; Sharif University of Technology
Springer Nature
2022
Abstract
The effect of the nucleating agent masterbatch carrier resin on the nonisothermal crystallization of a pipe-grade polypropylene block copolymer was investigated at three different cooling rates using differential scanning calorimetry (DSC). Bis(3,4-dimethylibenzylidene) sorbitol (DMDBS), a well-known, third-generation sorbitol derivative, was used as a nucleating agent in this study. Crystallization kinetic parameters obtained from DSC cooling curves showed that incorporation of a nucleating agent by means of a masterbatch increased the crystallization rate by approximately two times compared to that of the sample with the same concentration of nucleating agent without the use of a...
On the viscosity of composite suspensions of aluminum and ammonium perchlorate particles dispersed in hydroxyl terminated polybutadiene-New empirical model
, Article Journal of Colloid and Interface Science ; Volume 299, Issue 2 , 2006 , Pages 962-971 ; 00219797 (ISSN) ; Shojaei, A ; Sharif University of Technology
2006
Abstract
The rheological properties of fuel suspensions with various solid loadings up to close their maximum packing fraction and suspending media having different viscosities are investigated using the rotational viscometer at relatively low shear rates in which suspensions behave as Newtonian fluids. Aluminum (Al) and ammonium perchlorate (AP) particles are major solid components of any solid fuel system which should be distributed uniformly inside a polymeric binder based on hydroxyl terminated polybutadiene (HTPB). The experimental data generated in this investigation indicates that the relative viscosity of the suspensions is independent of viscosity of polymer binder, but in addition to solid...
Investigation of novel polyurethane elastomeric networks based on polybutadiene-ol/polypropyleneoxide mixture and their structure-properties relationship
, Article Materials and Design ; Volume 32, Issue 7 , 2011 , Pages 3933-3941 ; 02641275 (ISSN) ; Sadeghi, G. M. M ; Kashcooli, Y ; Sharif University of Technology
2011
Abstract
Polyurethane elastomer networks were designed and synthesized based on hydroxyl terminated polybutadiene/polypropyleneoxide (HTPB/PPO) mixtures, 2,4-toluene diisocyanate and 1,4-butanediol. Various networks with different molar ratio of HTPB to PPO (0/100, 25/75, 50/50, 75/25 and 100/0) had been prepared. Depending on the length of soft segment, average functionality of polyol mixtures, mechanical and thermal properties of samples were varied. Our observations confirmed that final properties of the networks can be attributed to two synergistic factors: (a) formation of chemical network (crosslinking) and (b) soft segment length. An optimum composition was found. This optimum composition...