Kinetics of the glass transition of styrene‐butadiene‐rubber: Dielectric spectroscopy and fast differential scanning calorimetry

An investigation of the glass transition of the antiferroelectric smectic C*A phase and cold crystallization of (S)-4’-(1-methylheptylcarbonyl)biphenyl-4-yl 4-[7-(2,2,3,3,4,4,4-heptafluoro- butoxy)heptyl-1-oxy]benzoate (denoted as 3F7HPhH6) by differential scanning calorimetry, polarizing optical microscopy and broadband dielectric spectroscopy is presented. The fragility index mf = 72, classifying 3F7HPhH6 as a glassformer with intermediate fragility, was obtained from the temperature dependence of the α-process relaxation time, measured upon cooling. Duplication of the α-process was observed exclusively upon heating, before the onset of cold crystallization, and is connected with the pre-transitional effect. The presence of two crystal phases likely influences the kinetics of cold crystallization; the idea stems from a comparison with previous results for the 3F7HPhF6 and 3F7HPhH7 compounds. Additionally, the presence of the smectic C*α; sub-phase in a narrow temperature range was proved based on the differential scanning calorimetry and broadband dielectric spectroscopy results, as well as the fractal dimension analysis of the textures obtained by polarizing optical microscopy.

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Higher tear strength of EPDM/SBR/TPR composites foam based on double foaming system

Journal of Elastomers & Plastics ◽

10.1177/0095244320933986 ◽

2020 ◽

pp. 009524432093398

Author(s):

Fuquan Deng ◽

Hua Jin ◽

Li Zhang ◽

Yuxin He

Keyword(s):

Cell Size ◽

Styrene Butadiene Rubber ◽

Butadiene Rubber ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

Polymeric Foam ◽

Tear Strength ◽

Crystallization Property ◽

Plastic Foams ◽

Styrene Butadiene

Polymeric foam with lightweight and higher impact strength has been used in many fields due to cost reduction and higher toughness. However, it is often difficult to improve their mechanical property especially tear strength. Here, a double foaming system was designed to increase the tear strength of the foamed ethylene–propylene–diene monomer, styrene–butadiene rubber, and thermoplastic rubber (EPDM/SBR/TPR) materials. The cell size of EPDM/SBR/TPR foam and cell distribution were investigated by scanning electron microscopy, which showed that the cells present a bimodal structure. Besides, the tear strength can reach up to 10 N/mm when the density is about 0.40 g/cm3, which is much superior to those of most engineering plastic foams. Meanwhile, the crystallization property of EPDM/SBR/TPR foams was also demonstrated by X-ray diffraction, thermogravimetric analysis, and differential scanning calorimetry, which indicates that the double foaming system can reduce the crystallization of EPDM/SBR/TPR molecular chains. In addition, the variation of thermal conductivity values depends on the gradual decrease effect of the cell size.

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INFLUENCES OF THE COMPATIBILITY OF NR/SSBR AND PHASE-SELECTIVE DISTRIBUTION OF SILICA ON ITS STATIC AND DYNAMIC PROPERTIES

Rubber Chemistry and Technology ◽

10.5254/rct.19.80439 ◽

2019 ◽

pp. 000-000

Author(s):

Qing-Yuan Han ◽

Xu Li ◽

Yu-Chun Li ◽

You-Ping Wu

Keyword(s):

Dynamic Properties ◽

Rolling Resistance ◽

Styrene Butadiene Rubber ◽

Butadiene Rubber ◽

Scanning Calorimetry ◽

Transmission Electron ◽

Bound Rubber ◽

Tan Δ ◽

Styrene Butadiene ◽

Wet Skid Resistance

ABSTRACT The compatibility between solution polymerized styrene–butadiene rubber (SSBR 2466) and natural rubber (NR) is characterized by differential scanning calorimetry and dynamic mechanical thermal analysis. The single glass transition in the entire temperature range of all NR/SSBR blends and good correlation between Tg and SSBR fraction prove the excellent compatibility between SSBR 2466 and NR. With increasing SSBR content, a reduced Payne effect, more homogeneous dispersion of silica, stronger rubber–filler interaction, and more silica selectively distributed in the SSBR phase were determined via rubber-processing analysis, transmission electron microscopy, bound rubber, and thermogravimetric analysis, respectively. The high vinyl content, low styrene content, and end-functionalized structure of SSBR play vital roles in promoting its compatibility with NR and a stronger rubber–silica linkage. The resulting increased tan δ at 0 °C and low tan δ at 60 °C indicates good wet-skid resistance and low rolling resistance by blending SSBR 2466, and 70/30 NR/SSBR is the best balance for producing a “green tire” tread.

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Assessing the Glass Transition Temperature of Nanocomposites Based on Copolymers of Styrene Butadiene Rubber, Polyisoprene, and Polybutadiene

International Polymer Science and Technology ◽

10.1177/0307174x1604301006 ◽

2016 ◽

Vol 43 (10) ◽

pp. 27-34

Author(s):

T.A. Matseevich ◽

A.A. Askadskii ◽

M.N. Popova ◽

O.V. Kovriga ◽

E.S. Afanas'ev

Keyword(s):

Glass Transition ◽

Transition Temperature ◽

Glass Transition Temperature ◽

Styrene Butadiene Rubber ◽

Butadiene Rubber ◽

Styrene Butadiene

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The glass transition and interfacial layer in styrene-butadiene rubber containing silica nanofiller

Polymer ◽

10.1016/s0032-3861(03)00667-0 ◽

2003 ◽

Vol 44 (20) ◽

pp. 6259-6266 ◽

Cited By ~ 207

Author(s):

V Arrighi ◽

I.J McEwen ◽

H Qian ◽

M.B Serrano Prieto

Keyword(s):

Glass Transition ◽

Interfacial Layer ◽

Styrene Butadiene Rubber ◽

Butadiene Rubber ◽

Styrene Butadiene

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Vulcanization kinetics of nano-silica filled styrene butadiene rubber

Polymer ◽

10.1016/j.polymer.2014.09.073 ◽

2014 ◽

Vol 55 (24) ◽

pp. 6426-6434 ◽

Cited By ~ 62

Author(s):

Seyed Mostaffa Hosseini ◽

Mehdi Razzaghi-Kashani

Keyword(s):

Styrene Butadiene Rubber ◽

Butadiene Rubber ◽

Nano Silica ◽

Vulcanization Kinetics ◽

Styrene Butadiene ◽

Kinetics Of

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Prediction of the glass transition temperature and design of phase diagrams of butadiene rubber and styrene–butadiene rubber via molecular dynamics simulations

Physical Chemistry Chemical Physics ◽

10.1039/c7cp00080d ◽

2017 ◽

Vol 19 (25) ◽

pp. 16498-16506 ◽

Cited By ~ 4

Author(s):

Myung Shin Ryu ◽

Hyoung Gyu Kim ◽

Hyun You Kim ◽

Kyung-Shin Min ◽

Hak Joo Kim ◽

...

Keyword(s):

Molecular Dynamics ◽

Glass Transition ◽

Transition Temperature ◽

Glass Transition Temperature ◽

Molecular Dynamics Simulations ◽

Phase Diagrams ◽

Styrene Butadiene Rubber ◽

Butadiene Rubber ◽

Dynamics Simulations ◽

Styrene Butadiene

In this study, we developed an equation to evaluate the pseudo-ternary Tg of quaternary SBR and plotted the ternary contour Tg plot for SBR with a variety of styrene compositions.

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A novel chemical technique for compatibility of ethylene-propylene-diene monomer rubber and styrene-butadiene rubber in their blends

Journal of Elastomers & Plastics ◽

10.1177/0095244316653262 ◽

2016 ◽

Vol 49 (4) ◽

pp. 298-314 ◽

Cited By ~ 2

Author(s):

Sara Estagy ◽

Saeed Ostad Movahed ◽

Soheil Yazdanbakhsh ◽

Majid Karim Nezhad

Keyword(s):

Mechanical Properties ◽

Heat Flow ◽

Classical Problem ◽

Styrene Butadiene Rubber ◽

Butadiene Rubber ◽

Ethylene Propylene Diene Monomer ◽

Scanning Calorimetry ◽

Covalent Bonds ◽

Ethylene Propylene ◽

Styrene Butadiene

The market for commercial polymer blends has grown steadily. A good blend should have strong interphases between different parts of the constituted polymers. Lack of strong interphases is a classical problem of the blend industry. Ethylene-propylene-diene monomer rubber (EPDM)/styrene-butadiene rubber (SBR) blends have a very good aging resistance and good compression sets. However, these rubbers are partially miscible. To improve the miscibility of EPDM and SBR in their blends, a Lewis acid, AlCl3, was used to form EPDM–g–SBR copolymer through Friedel–Crafts reactions. The existence of covalent bonds between EPDM and SBR macromolecules was studied by the cure traces of the blends, that is, ΔTorque, Fourier transform infrared spectrums, differential scanning calorimetry (DSC) heat flow curves, thermogravimetric analysis curves, and scanning electron (SEM) micrographs. Subsequently, several blends with EPDM/SBR ratio of 40/60 and with various AlCl3 amounts were prepared and after curing, their mechanical properties were measured and compared. The results showed covalent bonds formed between SBR–EPDM and SBR–SBR macromolecules. An exothermic change in heat flow in the DSC curve was observed around 111.28°C, which can be attributed to the formation of carbocations in Friedel–Crafts reactions. Adding 2 phr AlCl3 had an efficient effect on EPDM–SBR and or SBR–SBR linkages. The mechanical properties of the cured blends, that is, tensile strength were lower when compared with corresponding values for prepared compound with SBR. Excellent compatibility between the two polymers and strong interphases were observed in SEM micrograph of the cured blend with 1 phr AlCl3.

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