Ultimate tensile properties

Speckhard T.A. and Cooper S.L., Ultimate tensile properties of segmented pol3furethane elastomers Factors leading to reduced properties for pol3mrethane based on nonpolar soft segments. Rubber Chem. TechnoL, 59, 405, 1986. 

Elastic Modulus, Network Structure, and Ultimate Tensile Properties of Single-Phase Polyurethane Elastomers... 

The equilibrium shear modulus of two similar polyurethane elastomers is shown to depend on both the concentration of elastically active chains, vc, and topological interactions between such chains (trapped entanglements). The elastomers were carefully prepared in different ways from the same amounts of toluene-2,4-diisocyanate, a polypropylene oxide) (PPO) triol, a dihydroxy-terminated PPO, and a monohydroxy PPO in small amount. Provided the network junctions do not fluctuate significantly, the modulus of both elastomers can be expressed as c( 1 + ve/vc)RT, the average value of vth>c being 0.61. The quantity vc equals TeG ax/RT, where TeG ax is the contribution of the topological interactions to the modulus. Both vc and Te were calculated from the sol fraction and the initial formulation. Discussed briefly is the dependence of the ultimate tensile properties on extension rate. 

Table 8.9 First Ply Failure (FPF) and Ultimate Tensile Properties of Two Common Laminar Composites...

Smith,T.L., Frederick, . E. Ultimate tensile properties of elastomers. IV. Dependence of the failure envelope, maximum extensibility, and equilibrium stress-strain curve on network characteristics. J. Appl. Phys. 36,2996-3005 (1965). 

The viscoelastic and ultimate tensile properties of Kraton 101 (SBS copolymer containing 30.5% polystyrene and with total molecular weight 76000) and of Ther-... 

Figure 6- Change in ultimate tensile properties for a Viton material irradiated at 70°C using three different dose rates 5.5 x 10 rad/h (in air), 0 9.2 x 10 rad/h (in air), O 1 3 x 1

As an illustration, Figure 13 presents results for three different strain-rate and temperature conditions. The ultimate tensile properties are used to construct the failure criterion, and the ultimate simple shear properties verily the validity of the failure criterion. 

Block copolymers constituted so that the hard A blocks show increased glass temperatures might be expected to show better ultimate tensile properties than comparable block copolymers of a lower Tg in the glassy phase (12). This is demonstrated in the present system by substituting the major portion of the polystyrene in the present system for poly (a-methylstyrene). A short length of polystyrene is included at each chain end of the hard block to facilitate the second step of the synthesis and to give a more stable polymer. The effect of replacing... 

The tensile stress-strain measurements (Figure 8) indicate that the PNF s are becoming cross-linked upon irradiation, as evidenced by the increase in the ultimate tensile properties. 

The resulting cross-linked network can be characterized by studying the chemical and physical property changes that have occurred in the elastomers. The physical properties of vulcan-Izates that are usually evaluated are (a) modulus, (b) ultimate tensile properties, (c) swelling ratio, (d) glass-transition temperature (Tg), (e) dynamic mechanical properties and (f) creep... 

Smith, T.L., Dickie, R.A., 1969. Viscoelastic and ultimate tensile properties of styrene-butadiene-styrene block copolymers. J. Polym. Sci. Polym. Symp. 26 (1), 163-187. 

Pukanszky, B., Influence of interface interaction on the ultimate tensile properties of polymer composites. Composites, 21, 255-262 (1990). 

Properties of Acrylic Rubbers. The ultimate tensile properties of ACM vulcanizates are not as good as those of NR or NBR, but the tensile properties are sufficient for their applications. ACM grades can be used under certain conditions for 1000 hr at 160 to 170°C. ACM vulcanizates can withstand exposures of 1000 hr in oil at 150°C. In addition, ACM vulcanizates are very resistant to degradation by the action of ozone. 

One of the two ether linkages in PEEK is not present in PEK and the ensuing loss of some molecular flexibihty results in PEK having an even higher and heat-distortion temperature than PEEK A relatively higher ketonic concentration in the repeat unit results in high ultimate tensile properties as well. A comparison of different aromatic polyether ketones is given in Table As these properties are... 

Because of their high temperature and chemical resistance they are considered to be in the class of high-performance engineering plastics. PEK has a higher melting point and heat distortion temperature than PEEK, but PEEK is somewhat more flexible. PEK has relatively high ultimate tensile properties. 

A large increase in carbonyl index was noted, accompanied by a significant decrease in melting temperature (r ) index and ultimate tensile properties. 

Goettler. L.A. (1973) Ultimate tensile properties and composite structure of flow-molded short fiber composites, 31st ANTEC, Tech. Papers, 559-62. 

All PCL nanocomposites originated from the masterbatch remain rather ductile, with elongation at break higher than 300%. The stress at break slightly drops when the clay content is increased but remains at an acceptable level. Similar observations have been reported for the two organo-modified clays (Cloisite 25A and Cloisite 30B), that is increased stiffriess and preserved ultimate tensile properties. 

Tensile strength ASTM D6818, Standard Test Method for Ultimate Tensile Properties of Turf Reinforcement Mats ... 

The stress-strain curve of an elastomeric CEPC copolymer (prepared by hydrogenating an SIS) is also illustrated. This copolymer shows a tensile modulus that is intermediate between the 40% and 60% 1,2 EB-containing copolymers, with ultimate tensile properties that are very similar to the 40 % EB samples. 

The nominal tensile strength //Aq is the maximum tensile stress which a material is capable of sustaining. The maximum extensibility is the corresponding rupture strain A,. These ultimate tensile properties of elastomeric networks are very sensitive to temperature and test conditions, but can be characterized by a failure envelope which is generally represented by a plot of log(/ro/AoT) vs. log(A, — 1) where Tand To are respectively the test temperature and a reference temperature. ... 

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