Diene elastomers characterization

Kennedy, J. P. and Chou, T. Poly(isobutylcnc-co-(J-Pinenc) A New Sulfur Vulcanizable, Ozone Resistant Elastomer by Cationic Isomerization Copolymerization. Vol. 21, pp. 1-39. Kennedy, J. P. and Delvaux, J. M. Synthesis, Characterization and Morphology of Poly(buta-diene-g-Styrene). Vol. 38, pp. 141-163. 

THERMALAND SPECTROSCOPIC (VIBRATIONAL AND NUCLEAR MAGNETIC RESONANCE) CHARACTERIZATION OF ETHYLENE-PROPYLENE-DIENE (EPDM) ELASTOMERS... 

Halogenation and hydrohalogenation of elastomers have been reported extensively in the literature [26]. The main problems with these reactions are the cyclization and chain scission that occur parallel to the halogenation reaction. These introduce difficult problems in the characterization of the resulting products. Despite these problems, several products have been prepared and commercialized. Chlorination of poly(l, 4-butadiene) to prepare a product similar to poly(vinyl chloride) has been reported by several workers [27]. This process had extensive side reactions and chain degradation. The chlorination of butyl rubber and conjugated diene-butyl rubbers gives end products that are used in the tire industry as inner liners for air retention. 

TPO materials are defined as compounds (mixtures) of various polyolefin polymers, semicrystalline thermoplastics, and amorphous elastomers. Most TPOs are composed of polypropylene and a copolymer of ethylene and propylene called ethylene—propylene rubber (EPR) [2]. A common rubber of this type is called ethylene propylene diene monomer rubber (EPDM), which has a small amount of a third monomer, a diene (two carbon-carbon double bonds in it). The diene monomer leaves a small amount of unsaturation in the polymer chain that can be used for sulfur cross-linking. Like most TPEs, TPO products are composed of hard and soft segments. TPO compounds include fillers, reinforcements, lubricants, heat stabilizers, antioxidants, UV stabilizers, colorants, and processing aids. They are characterized by high impact strength, low density, and good chemical resistance they are used when durability and reliability are primary concerns. 

Swollen elastomers have domains of solvent between the network chains that may also he considered pores. fhermoporometry is useful to characterize the pore size and size distribution in such gels. Examples include natural ruhher, - styrene-divinylhenzenepolymers, poly(ethylene oxide),polyethylene and polypropylene, and ethylene-propylene-diene polymers and cis-polycyclo-octene. ... 

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