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Investigation on the Role of Curing System on the Cure Kinetics and Network Structure of NR/SBR Blend Filled with Nanodiamond

, M.Sc. Thesis Sharif University of Technology Rabiei, Sima (Author) ; Shojaei, Akbar (Supervisor)

Abstract

Vulcanization is one the most crucial process in elastomer manufacturing products. It has been shown that network structure and curing kinetic are strongly dependent on curing system formulation. In addition reinforcing fillers in elastomers can affect them as well. By commencement of nanofillers in rubber domain, effects of nanofiller presence on rubber behavior have been investigated by reaserchers.
In this Project the effect of different curing system formulations on vulcanization kinetic and network structure of NR/SBR elastomeric matrice filled by nanodiamond is investigated. Different ingredients and nanodiamond were added to matrix by mechanical mixing in two roll mill. The...

محتواي کتاب

Molecular structure and physical properties of E-beam crosslinked low-density polyethylene for wire and cable insulation applications

, Article Journal of Applied Polymer Science ; Volume 86, Issue 8 , 2002 , Pages 1959-1969 ; 00218995 (ISSN) Dadbin, S ; Frounchi, M ; Haji Saeid, M ; Gangi, F ; Sharif University of Technology

2002

Abstract

Crosslinking of homemade low-density polyethylene (LDPE) was performed by electron-beam (EB) irradiation. The gel content of the EB-exposed LDPE was determined by the solvent-extraction method. The degree of crosslinking was also evaluated by a hot set measuring test. The results obtained from both the gel-sol and the hot set methods showed that the degree of crosslinking was dependent on the deposited energy in LDPE samples. Increasing the absorbed dose increased the degree of network formation. The LDPE with higher molecular weight yielded higher efficiency of crosslinking at the same irradiation dose. The effect of irradiation dose on the molecular weight between crosslinks (Mc),...

Comparison between electron-beam and chemical crosslinking of silicone rubber

, Article Nuclear Instruments and Methods in Physics Research, Section B: Beam Interactions with Materials and Atoms ; Volume 243, Issue 2 , 2006 , Pages 354-358 ; 0168583X (ISSN) Frounchi, M ; Dadbin, S ; Panahinia, F ; Sharif University of Technology

2006

Abstract

Silicone rubber (SR) was irradiated by electron beam over a dose range of 50-300 kGy in the absence of chemical reagents. Molecular weight between crosslinks (Mc) in the network of SB was determined by two methods of solvent swelling and modulus of elasticity. The network structure of the elastomer crosslinked by electron beam irradiation and chemical vulcanization was compared. Mechanical tests were performed to determine shore hardness, tensile elongation, strength and modulus of the samples. It was found that SR is effectively crosslinked by electron beam irradiation. The tensile strength, hardness, modulus and elongation of irradiated SR were higher than peroxide-crosslinked SR. The...

Investigation the Effect of Antioxidant on Amount of Crosslink and Mechanical Behavior of Peroxide Crossliked Polyethylene (PEX-A)

, M.Sc. Thesis Sharif University of Technology Berarzadeh Grivdehy, Meisam (Author) ; Pircheraghi, Gholamreza (Supervisor)

Abstract

Polyethylene is the most widely used plastic material in the world for reasons such as lightweight, good strength, good processability, low cost, and low maintenance cost, and very good chemical resistance. One of the applications of polyethylene that has received much attention in recent decades is its use in the manufacture of hot water pipes. To maintain the properties of polyethylene at high temperatures, it must be crosslinked at a proper level. Appropriate antioxidants should be used to prevent the degradation and oxidation of polyethylene during the process as well as long-term operation. Concomitant use of phenolic antioxidants for long-term stability during service and phosphorus...

محتواي کتاب

Vulcanization kinetics and reversion behavior of natural rubber/styrene-butadiene rubber blend filled with nanodiamond - The role of sulfur curing system

, Article European Polymer Journal ; Volume 81 , 2016 , Pages 98-113 ; 00143057 (ISSN) Rabiei, S ; Shojaei, A ; Sharif University of Technology

Elsevier Ltd 2016

Abstract

The effect of nanodiamond (ND) particles on the network structure and vulcanization kinetics of natural rubber (NR)/styrene-butadiene rubber (SBR) blend vulcanized by three different curing systems, namely conventional (CV), semi-efficient (SEV) and efficient (EV), was investigated. The filler dispersion, crosslink density, curing kinetics and reversion behavior were fully studied. The state of ND dispersion in the rubber matrix was investigated by the field emission scanning electron microscope (FESEM). Swelling experiments and tensile tests exhibited that upon incorporation of ND crosslink density of NR/SBR blend was enhanced significantly due to the large surface area of nano filler...

Effects of rubber curing ingredients and PhenolicResin on mechanical, thermal, and morphological characteristics of rubber/phenolic-resin blends

, Article Journal of Applied Polymer Science ; Volume 108, Issue 6 , 2008 , Pages 3808-3821 ; 00218995 (ISSN) Derakhshandeh, B ; Shojaei, A ; Faghihi, M ; Sharif University of Technology

2008

Abstract

This article examines the physical and mechanical characteristics of mixtures of two different synthetic rubbers, namely styrene-butadiene rubber (SBR) and nitril-butadiene rubber (NBR), with novolac type phenolicresin (PH). According to Taguchi experimental design method, it is shown that the addition of PH increases the crosslinking density of rubber phase probably due to its curative effects. Thermal analysis of the blends indicates that, contrary to NBR/PH blend, thermal stability of SBR/PH blend is dependent on sulfur content due to predominant polysulfidic crosslinks formed in SBR. Slight shift in glass-transition temperature (Tg) of pure SBR and NBR vulcanizates by the addition of PH...