Olefinic TPES

Commercial IPNs have been developed to combine useful properties of two or more polymer systems. For example, high levels of silicone have been combined with the thermoplastic elastomer (TPE) based on Shells Kraton styrene-ethylene/butadiene-styrene TPE and Monsantos Santoprene olefin TPE. These IPN TPEs are said to provide the biocompatibility and release properties of silicone with tear and tensile strength up to five times greater than medical-grade silicone. Thermal and electronic properties and elastic recovery are also improved. 

Thermoplastic olefin (TPE-0 or TPO) Low gloss and density High stiffness and toughness Recyclability Can be easily injection-molded to form various parts in IP—is used more as skin of PP foam in recent vehicles. [28]... 

The traditional role of carpeting plus rubber or PVC mats as the flooring surface is being challenged by noncarpet alternatives (1) based on olefinic TPEs capable of a more utilitarian function (e.g., washable) and decorative look (colors, printed patterns, and molded-in decorative effects). Polypropylene carpet floor surfaces are increasing their share of the market (13), further supporting the drive for mono-material construction based on polyolefins. 

Current cost reduction demands point toward an on-board or on-module acoustic system integrated with the original layer structure of the module. This economic drive combined with the benefits of a monolithic, multilayer design bring a market growth opportunity for low-cost olefinic TPEs to compete with incumbents on the basis of ... 

Ionic polymers are a special class of polymeric materials having a hydrocarbon backbone containing pendant acid groups. These are then neutralized partially or fully to form salts. lonomeric TPEs are a class of ionic polymers in which properties of vulcanized rubber are combined with the ease of processing of thermoplastics. These polymers contain up to 10 mol% of ionic group. These ionomeric TPEs are typically prepared by copolymerization of a functionalized monomer with an olefinic unsamrated monomer or direct functionalization of a preformed polymer [68-71]. The methods of preparation of various ionomeric TPEs are discussed below. 

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. 

TPEs are blends of various amorphous rubbers such as ethylene-propylene and of polyolefin semicrystalline plastics such as PP. They are part of the family of TP olefins (TPOs). TPOs are mechanical blends consisting of a hard plastic and softer rubber. They are considered different from blends that are dynamically thermoplastic vulcanized (TPV) a process in which the elastomer phase is cured during mixing of the polymers.84 94... 

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. 

TPE-0 Thermoplastic olefin elastomer, uncross-Iinked Blend... 

TPOs (olefinic blends) comprise a lower-performance, lower-cost class of TPEs (Fig. 4.39). Their performance and properties are generally inferior to those of thermoset rubbers. Yef they are suitable for uses where (1) the maximum service temperature is modest (below 80°C), (2) nonpolar flnid resistance is not needed, and (3) a high level of creep and set can be tolerated. Thns, TPOs are marketed more on the basis of cost rather than performance, competing directly with the lower-cost general-purpose rubbers (NR, SBR, and the hke). TPOs are associated with the traditional practice of rnbber componnd-ing and mixing. They can be prepared by the same techniques and equipment as for thermoset mbber however, they need to be processed at temperatures above the of the thermoplastic hard phase. The amounts of elastomer, rigid thermoplastic, plasticizer, and other ingredients can be varied to achieve specific properties in much the same manner as with rnbber componnds. 

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