Thermoplastic Olefin Elastomers TPO

Ziegler-Natta catalyst makes it possible to polymerize a-olefins into elastomers with controlled degree of crystallinity and cross-likability. The first EPR s were manufactured in 1960, 3 years later, the first EPDM. It is advantageous to produce block copolymers with PP being the rigid and PE the soft block. A direct sequential polymerization of propylene and ethylene-propylene mixture leads to the reactor blends (R-TPO) (Cecchin and Guglielmi 1990). 

Polytransoctanamer (PTO) has been used as a high-performance elastomer and in blends with commodity and engineering resins. Polyoctadecene (POD) blends with PP are thermochromic. The most interesting are the metallocene-type polycyclic polyolefins, e.g., polycyclopentene or polynorbomene, either syndiotactic or isotactic with T = 400-600 °C. 

PP with 18-32 wt% EVAe and/or ethylene-ethylacrylate copolymer (EEA) Impact strength, elongation, and low-T brittleness Miller and Reddeman 1962 

PP with EVAc Dyeability, flexibility, barrier properties, and toughness Sakata et al. 1968 

70 wt% PP and EVAc, PVCAc, HOPE Low-temperature impact resistance Kojima and Tanahashi 1972 

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Blends of EPDM rubbers with polypropylene in suitable ratios have been marketed as thermoplastic elastomers (TPE), also commercially known as thermoplastic polyolefin elastomers (TPO). These heterophasic polymers, characterized by thermoreversible interaction among the polymeric chains, belong to a broad family of olefinic alloys that can now be produced directly during the polymerization phase, unlike blended TPE and TPO, and various compositions (with various compounding additives) can be formulated which are primarily tailored to meet different requirements of most of car applications. The TPE-based synthetic leather and foam sheets are typical examples. 

As a consequence, before 1953, the only possible blends were those of LDPE with other polymers than PO or with elastomers (e.g., chlorosulfonated polyethylene rubber, CSR chlorinated butyl mbber, CBR ethylene/propylene/diene copolymers, EPR, EPDM thermoplastic olefinic elastomer TPE, TPO). However, in addition to the original autoclave polymerization, already in 1938, a tubular reactor was introduced and its product had different properties than that from the autoclave. Also varying the reaction condition affected the degree of short- and long-chain branching in LDPE thus, blending different LDPEs offered a way for optimizing the resin to specific applications. 

TOE Catalyst turnover frequency TPE Thermoplastic elastomer TPO Thermoplastic olefinic elastomer TPU Thermoplastic urethanes TPV Thermoplastic vulcanizate TR Tubular reactor... 

A patent on reactor-blended thermoplastic olefinic elastomer, R-TPO, was disclosed. Thus, PE was polymerized in the presence of an active catalyst and an already polymerized olefinic copolymer (e.g., ethylene-co-1-butene) or the sequence was reversed. The blend had superior resistance to environment stress cracking, and the blown film showed few fish eyes... 

The first patent on reactor-blended thermoplastic olefinic elastomer, R-TPO, was disclosed. 

Montell s in-reactor Catalloy ( catalytic alloy ) polymerization process alloys propylene with comonomers, such as EPR and EPDM, yielding very soft, very hard, and rigid plastics, impact grades or elastomeric TPOs, depending on the EPR or EPDM % content. The term olefinic for thermoplastic olefinic elastomers is arguable, because of the generic definition of olefinic. TPVs are composed of a continuous thermoplastic polypropylene phase and a discontinuous vulcanized rubber phase, usually EPDM, EPR, nitrile rubber, or butyl rubber. 

Thermoplastic elastomers (TPEs) are either block copolymers (SBS, SEES, SEPS, TPU, COPA, COPE) or blends, such as TPO (elastomer/hard thermoplastic, also referred to as thermoplastic olefin) and TPV (fhermoplastic vul-canizafe, blend of a vulcanized elastomer and a hard fhermoplastic). These types represent the majority of fhe TPEs other types are either specialty or small-volume materials. 

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

Let us first review the various thermoplastic elastomers used in automotive applications. These are styrenic block copolymers (SBCs), thermoplastic olefins (TPOs) (cross-linked... 

In 1979 UNIPOL process for gas-phase production of LLDPE was introduced by the UCC. Since the new resins were difficult to process on the LDPE processing lines, several patents were issued for LLDPE blends with, e.g., LDPE or PP, which had better processability In 1982 a number of patent applications for blends of LLDPE, with other polyolefins, co-polyolefins, and olefinic elastomers, for example, ethylene copolymers and thermoplastic elastomers (e.g., TPO, EPDM, EPR, EVAc, PP-MA,), have been filed... 

Forprene Olefinic thermoplastic elastomers, TPO Ferro Corp. 

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