Styrene-butadiene rubber tests

FIGURE 26.20 The log a v speed function of the previous chart is combined with the friction master curves for a natural rubber (NR) and a styrene-butadiene rubber (SBR) gum compound on glass showing the limited range of friction values (and their position on the log a-iv axis for different testing conditions) which are obtained when the sliding speed is increased. 

TABLE 2. Low Loss Factor Testing Results for Compounded Poly(styrene-butadiene) Rubber"... 

Testing of the mechanical properties revealed that the nano-powdered styrene/butadiene rubber is effective in toughening PS (6). 

Standard test method for rubber chemical analysis for polystyrene blocks in SBR (styrene-butadiene rubber) and styrene-reinforced lat-ices, ASTM Standard ASTM D3314-02, ASTM International, WestCon-shohocken, PA, 2006. 

The Delta Mooney (A Mooney) test is an extension of the Mooney used on empirical grounds as a general indication of processibility for non-pigmented oil extended emulsion styrene/butadiene rubber. It quantifies the changes that occur in Mooney viscosity with time, either as the difference between viscosities recorded at two specified times or as the difference between the minimum viscosity recorded immediately after the commencement of the test and the subsequent maximum viscosity. Several alternative Delta Mooney values are defined depending on the times, whether minimum/maximum viscosity difference is used and whether or not the sample has been massed on a mill. Procedures for Delta Mooney are standardised in ISO 289-341, BS 903 Part A58-142 and in ASTM D334643. 

Vapors from natural rubber (NR) produce a deep blue or blue-violet color, and those from styrene-butadiene rubber (SBR) pyrolysis turn the paper green or blue with a distinct green tinge. Polyisobutylenes and butyl rubber resemble NR, and silicone rubbers resemble SBR, in this color reaction. Pyrolytic vapors from nitrile rubbers, on the other hand, give a brown or brown-yellow color and those from polychloroprenes (neoprene) turn the test paper grey with a yellow tinge. 

ISO 9022-11 1994 Optics and optical instruments — Environmental test methods — Part 11 Mould growth ISO 9026 1991 Raw rubber or unvulcanized compounds — Determination of green sbength ISO 9924-1 2000 Rubber and rubber products — Determination of the composition of vulcanizates and uncured compounds by thermogravimetry — Part 1 Butadiene, ethylene-propylene eopolymer and terpolymer, isobutene-isoprene, isoprene and styrene-butadiene rubbers... 

In some uncomplicated examples, it has been possible to analyse the results of adhesion tests to obtain numerical values associated with interfacial forces. An example of this was the work of E. H. Andrews and A. J. Kinloch, who measured the adhesion of SBR (styrene - butadiene rubber) to different polymeric substrates over a range of temperatures and test rates. Three types of tests including a 90° peel test were used. The results were analysed to evaluate the fracture energy per unit area G. (For the peel test, G was P, the peel energy.)... 

Arantes, T., Leao, K., Tavares, M., Ferreira, A. NMR study of styrene-butadiene rubber (SBR) and Ti02 nanocomposites. Polym. Testing 28, 490-494 (2009)... 

P. T. Hao, H. Ismail, A. S. Hashim, Study of two types of styrene butadiene rubber in tire tread compounds, Polym Test, 2001, 20, 539. 

Fig. 4 Experimental data on carbon black-reinforced styrene butadiene rubber Iot tensile (circle) and pure shear (square) tests [57]. The ratio of the tangent stiffiiess around the undeformed configuration, i.e., nominal strain equal to 1, is approximately equal to 3...

Fig. 14 Strain sweep tests on a pure atactic polypropylene and an unfilled styrene-butadiene rubber compound using either an open-gap (VCOR) or a closed-cavity (RPA) torsional dynamic rheometer (authra- s experimental data)...

This paper discusses the properties of polymer-modified mortars with silica fume. The polymer-modified mortars using a styrene-butadiene rubber latex and an ethylene-vinyl acetate emulsion are prepared with various polymer-cement ratios and silica fume contents, and tested for flexural and compressive strengths, adhesion, water absorption and permeation, water resistance, drying shrinkage, carbonation and chloride ion penetration. The effects of the polymer-cement ratio and silica fume content on the properties of the polymer-modified mortars are e>amined. In conclusion, the addition of the silica fume causes improvements i- the compressive strength, resistance to water permeation and chloride ion penetration. However, the adhesion, resistance to water absorption and carbonation and drying shrinkage are not improved by silica fume addition. 

Figure 18 Variation of fracture energy with testing rate and temperature for styrene-butadiene rubber...

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