Thermoplastic olefinic elastomer

Processing oil is a well-known additive for rubbers and is commonly employed in PP/EPDM TPVs [10-12]. It lowers the hardness and improves the processability. The oil, in most cases paraffinic oil, can be considered as a low molecular weight olefin. The difference in polarity between the three components is small, and the oil is present in both the PP and in the elastomer phases [67]. In order to understand the mechanical and the rheological properties of olefinic thermoplastic elastomers (OTPEs), the concentration of oil in each phase must be known. 

Olefinic thermoplastic elastomers are block copolymers or blends of polyolefins — commonly, polypropylene, which forms the hard crystalline block, and another olefin block, most commonly ethylene or EPDM. Some less common soft segments include natural rubber, nitrile rubber, and EVA. Olefinic thermoplastic elastomers exhibit better processability than neoprene and have excellent resistance to oils. Therefore, they offer attractive replacements for neoprene in oil-resistant wire and cable insulation. 

Category Olefinic Thermoplastic Elastomers (TPOs) are typically called thermoplastic olefins. 

Olefinic Thermoplastic Elastomers Blends of EPDM or EP rubbers with polypropylene or polyethylene, optionally eross-linked. Has low density, good dielectric and mechanical properties, and processibility but low oil resistance and high flammability. Processed by extrusion, injection and blow-molding, thermoforming, and calendering. Used in auto parts, construction, wire jackets, and sporting goods. Also called TPO. 

Adpro AP Reactor olefinic thermoplastic elastomers, RTPO Genesis Polymers... 

Forprene Olefinic thermoplastic elastomers, TPO Ferro Corp. 

Recently, impact modifiers have been developed for plastics other than PVC. Polybutylene and other olefinic thermoplastic elastomers, for example, are being used to enhance the processability, toughness, and heat stability of polypropylene film. Hydroxy-terminated polyethers are being used to increase the impact resistance of polystyrene. Other conunon applications are polycarbonate, polyurethane, thermoplastic polyester, epoxy, and polysulfone. 

Figure 9.2 A stamping identifying the plastic used in an automotive bumper. The resin used in the production of this Daimler-Chrysler part is identified as TEO (Olefinic Thermoplastic Elastomer), more commonly known as TPO (thermoplastic polyolefin) [126],...

Thermoplastic Elastomers (TPE) are classes of heterophasic polymers, characterized by thermo-reversible interaction among the polymeric chains. The new polymeric materials that are considered to produce easy recyclable automotive systems, can be defined as a sort of a new generation of Olefinic Thermoplastic Elastomers (TPO), belonging to a broad family of polyolefinic alloys that can now be produced directly dining the polymerization phase. These completely new materials, resulting from advanced research and development carried out by HIMONT, can be tailored in order to meet different requirements of most of car apphcations. The basic partly finished components suitable for the constructions of the main automotive composite structru-es will be described. 

Olefinic thermoplastic elastomer (TPO) materials are defined as compounds (mixfures) of various polyolefin polymers, semicrysfalline thermoplastics, and amorphous elastomers. Most TPOs are composed of polypropylene and a copolymer of ethylene and propylene called ethylene-propylene rubber (EPR) [10]. A common rubber of this type is called ethylene-propylene diene monomer (EPDM) rubber, 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. 

Swelling has consequential implications for the apphcations of polymers, particularly elastomers where solvent contact is likely. For example, olefinic thermoplastic elastomers are not affected by water or aqueous solutions of chemicals and resist acids and bases. Hydrocarbon solvents tend to swell and soften TPO products. This effect is much more pronounced for softer grades. Cross-linking (vulcanization) is used to improve mechanical properties, to reduce swelling in oils and solvents, and to... 

Nele M and Soares J B P (2003) Molecular weight and long chain branch distributions of branch-block olefinic thermoplastic elastomers, Macromol Theor Simul 12 386-400. 

If the rubber content of a PP blend is less than 50%, then the material may be referred to as rubber reinforced polypropylene (RRPP) or, as rubber modified polypropylene ( PP) or, as an elastomer modified thermoplastic MT) or, as an olefin thermoplastic elastomer (OTE) or, as impact modified polypropylene (IMPP). The material may also be known as a thermoplastic elastomer (TFE) or, as a thermoplastic rubber (TPR). The rubber/elastomer in such a mbcture is not crosslinked, or cured, or vulcanized). The term rubber reinforced PP (RMPP) will be used for those systems in which the rubber is present in relatively low concentations (<30%) and is not cross-linked/cured. 

Rubber modified polypropylene polypropylene/ethylene propylene rubber blends ethylene propylene rubber, polypropylene blends elastomer modified thermoplastic elastomer modified polypropylene impact modified polypropylene olefin thermoplastic elastomer thermoplastic polyolefc rubber. 

Sengers WGF, Wubbenhorst M, Picken SJ, Gotsis AD. Distribution of oil in olefinic thermoplastic elastomer blends. Polymer 2005 46( 17) 6391-6401. 

Ethylene copolymers are produced i) with vinyl acetate (EVA, EVAC), ii) with vinyl alcohol (EVOH, EVAL), iii) as binary copolymers and terpolymers with acrylics (E/EA, E/MA, E/AA etc.), or iv) as lonomer resins. Olefinic thermoplastic elastomers (TPE) are available, usually PP based with EPM or EPDM rubber additions that may be lightly crosslinked. Polypropylenes are offered in various forms homopolymers, block copolymers, random copolymers and mixtures of types. Polybutylene (PB) and Polymethylpentene (PMP) complete the range. 

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