Rubber vulcanization properties

Chloro-4,6-bis(methylsulfanyl)-l,3,5-triazine (15) on reaction with disodium tetrasulfide forms a bidentate bistriazine molecule 16 which is linked by a sulfane chain.103 This type of compound exhibits excellent rubber-vulcanization properties. 

ISO 37 1994 Rubber, vulcanized or thermoplastic - Determination of tensile stress-strain properties... 

ISO 844 2001 Rigid cellular plastics - Determination of compression properties ISO 3386-1 1986 Polymeric materials, cellular flexible - Determination of stress-strain characteristics in compression - Part 1 Low-density materials ISO 3386-2 1997 Flexible cellular polymeric materials - Determination of stress-strain characteristics in compression - Part 2 High-density materials ISO 5893 2002 Rubber and plastics test equipment - Tensile, flexural and compression types (constant rate of traverse) - Specification ISO 7743 2004 Rubber, vulcanized or thermoplastic - Determination of compression stress-strain properties... 

ISO 1663 1999 Rigid cellular plastics - Determination of water vapour transmission properties ISO 2556 1974 Plastics - Determination of the gas transmission rate of films and thin sheets under atmospheric pressure - Manometric method ISO 6179 1998 Rubber, vulcanized or thermoplastic - Rubber sheets and rubber-coated fabrics - Determination of transmission rate of volatile liquids (gravimetric technique)... 

ISO 3934 2002 Rubber, vulcanized and thermoplastic - Preformed gaskets used in buildings - Classification, specifications and test methods ISO 4649 2002 Rubber, vulcanized or thermoplastic - Determination of abrasion resistance using a rotating cylindrical drum device ISO 4664-1 2005 Rubber, vulcanized or thermoplastic - Determination of dynamic properties - Part 1 General guidance... 

ISO 7619-2 2004 Rubber, vulcanized or thermoplastic - Determination of indentation hardness - Part 2 IRHD pocket meter method ISO 7743 2004 Rubber, vulcanized or thermoplastic - Determination of compression stress-strain properties... 

Rubber, vulcanized Determination of the effect of liquids Standard test method for rubber property-effect of liquids Standard test method for rubber property Change in length during liquid immersion Determination of the behavior of rubbers and elastomers when exposed to fluids and vapors Determination of the effect of liquids Determination of equilibrium water vapor absorption... 

Use and exposure Diborane is a colorless gas at room temperature with a repulsive, sweet odor. It mixes well with air and easily forms explosive mixtures. Diborane will ignite spontaneously in moist air at room temperature and can cause explosions. Diborane is used in rocket propellants and as a reducing agent, a rubber vulcanizer, a catalyst for hydrocarbon polymerization, a flame-speed accelerator, and a doping agent. Diborane is a very toxic and flammable gas used by chemists to make other compounds. It is also used in electronics to impart electrical properties in pure crystals. Industrial workers are exposed to diborane by breathing in its vapors in work areas. - ... 

PA-6-66 copolymer (35)-NBR (65) vulcanizate) (50) / (PP(50)-EPDM(50) vulcanizate) (50) / PP-MA (10) internal mixer at 220°C / PA + rubber vulcanization and PP + rubber performed in separate steps before blending / mechanical properties vs. use of unfunctionalized PP / comparison to use of functionalized PP in initial vulcanizate / PP-f-carboxymethyl maleamic acid Coran et al., 1985... 

ISO 37— Rubber, vulcanized or thermoplastic—Determination of ten.sile stress-strain properties (1994). 

TPV nanocomposites of LLDPE/reclaimed rubber with nanoclay and 1 wt.% MA-grafted PE and curative were prepared using a Brabender internal mixer at 170°C (Razmjooei et al., 2012). Contents of the reclaimed rubber, nanoclay, and compatibilizer were varied up to 30, 7, and 21 wt.%, respectively. The blends without the compatibilizer were also prepared. Morphological, thermal, and mechanical properties of the nanoclay-reinforced TPV nanocomposites indicated intercalation and partial exfoliation by the high-shear stress during mixing with the reclaimed rubber. Vulcanization of rubber phase led to an increase of viscosity. The size of rubber particles in TPV was reduced with the addition of nanoclay and compatibilizer. 

Properties Insol. in carbon disulfide Uses Rubber vulcanizing agent controls bloom, preserves building tack, prevents sulfur migration in rubber prevents crystallization of sulfur on uncured rubber Trade Name Synonyms Crystex 60 [Flexsys http //www.flexsys.com], Crystex Regular [Flexsys http //www.flexsys.com], OT-20 [Chemconserve... 

Amorphous copolymers of ethylene and propylene, EPM, also possess rubber-elastic properties. But they cannot be vulcanized with sulfur because of the absence of carbon-carbon double bonds, and so a special technique using peroxides as free radical sources for transfer reactions has had to be developed. However, polymerizing in a diene component such as, for example, cyclopentadiene or ethylidene norbornene, leads to the formation of what are known as EPDM rubbers with double bonds in the side chains. These can, on the one hand, be vulcanized in the classic way with sulfur, but, on the other hand, still have good aging properties. Consequently, EPDM rubbers are mainly used in automobile construction, the cable and construction industries, as well as for technical purposes. However, the EPDM rubbers have only slight self-adhesion, so that producing tires from cut sections is made more difficult. It is for this reason that EPDM rubbers are not used for tires. 

ISO 37 Rubber, vulcanized or thermoplastic— Determination of tensile stress—strain properties... 

Properties. Typical raw polymer and vulcanized properties of synthetic IR are similar to those of NR. Both exhibit good inherent tack, high compounded gum tensile strength (green strength), and good vulcanizate hysteresis (low values) and tensile properties. In synthetic IR, there is minimal variance in physical properties lot to lot, and there is a low concentration of nonrubber constituents compared to natural rubber. 

Many applications are being found for synthetic rubbers, which are synthetic polymers possessing rubber-like properties. Among those available commercially are butadiene-styrene and butadiene-acrylonitrile (called Buna rubbers), polyisoprene, and polybutadiene. Their properties may be modified considerably more than vulcanized rubbers, particularly with respect to resistance to oxidizing agents, solvents, and oils. Their adhesion to metals, however, is generally poorer. 

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