Elastomers specific gravity

Elastomer Specific gravity Hardness, Shore A Tensile strength, MPa" Elongation, % Resihence Compression e set Impermeability e to gases... 

Fillei Specific gravity Compatible elastomer Uses... 

Chlorinated polyethylene (CPE) has excellent o2one, oil, and heat resistance. In addition chlorinated polyethylene has replaced chloroprene elastomers. CPE has a lower specific gravity than chloroprene compounds and produces compounds that are similar to CR in properties but with lower costs. In addition, due to high levels of chlorine in the polymer, the flame resistance of the compounds of CPE are high. 

Elastomer ECH, % Chlorine, % Ethylene oxide, % CAS Registry Number Specific gravity ml T,°C... 

Global consumption of thermoplastic mbbers of all types is estimated at about 600,000 t/yr (51). Of this, 42% was estimated to be consumed in the United States, 39% in Western Europe, and 19% in Japan. At present, the woddwide market is estimated to be divided as follows styrenic block copolymers, 48% hard polymer/elastomer combinations, 26% thermoplastic polyurethanes, 12% thermoplastic polyesters, 4% and others, 9%. The three largest end uses were transportation, 23% footwear, 18% and adhesives, coatings, etc, 16%. The ranges of the hardness values, prices, and specific gravities of commercially available materials are given in Table 4. 

Spectrophotometic identification of elastomer or pyrolyzate Specific gravity Percent ash where applicable Ultraviolet spectrophotometry of extracts... 

C poly 1,4-isoprene has a specific gravity of 0.91, a coefficient of linear expansion of 67 X 10 9 cm/cm C, and a refractive Index of 1.5191. This and other elastomers retain their characteristic mobility at temperatures above the Tt. They are brittle at temperatures below Tg. 

Basic properties. The basic properties of ECH elastomers can also be found in detail in the above-mentioned reviews [108-110]. The homo-and copolymers have a high specific gravity (1.4-1.5). The Mooney viscosities are of the same range as for other commercial elastomers. Ozone, heat, fuel and oil resistance are good. An excellent resistance to vapor permeation by hydrocarbons, fluorocarbons, and air was observed. 

Elastomers are generally purchased on weight basis but used on volume basis. Consequently, TPEs offer cost advantages since they normally have lower specific gravity than thermoset lubbeis. 

D 395 Test Method for Rubber Property - Compression Set D 412 Test Method for Vulcanized Rubber, Thermoplastic Rubbers and Thermoplastic Elastomer - Tension D 471 Test Method for Rubber Property - Effect of Liquids D 570 Test Method for Water Absorption of Plastics D 624 Test Method for Tear Strength of Conventional Vulcanized Rubber and Thermoplastic Elastomer D 638 Test method for Tensile Properties of Plastics D 792 Test Method for Specific Gravity (Relative Density) and Density of Plastics by Displacement... 

Shore hardness can be as soft as 70 A and as hard as 74 D, depending on the hard/soft segment ratio. Specific gravity, modulus, compressive stress, load-bearing strength, and tear strength are also hard/soft ratio dependent. TPU thermoplastic elastomers are tough, tear resistant, abrasion resistant, and exhibit low-temperature properties. ... 

Today, TPOs are used increasingly in special automotive applications because of their lower specific gravity, injection moldability, economics, recyclability, and noise performance. Some variations of these essential ingredients either are compounded in extruders (other mixers) or are prepared in some combination of reactors (often referred to as reactor TPO) that can make both PP and the rubber followed by some post-reactor addition of other chemicals. Toyota Super Olefin Polymer (TSOP) is a special type of TPO offered primarily in Japan.7 It is highly differentiated in its flow characteristics, modulus, and balance of low-temperature properties due to some unusual shared continuous morphology achieved through a unique fabrication route of PP and elastomer blend. The ratio of elastomer to PP in this blend can be adjusted to control the modulus and elastic recovery of a TPO. ... 

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