Blends thermoplastic elastomers

Compatibilization along with dynamic vulcanization techniques have been used in thermoplastic elastomer blends of poly(butylene terephthalate) and ethylene propylene diene rubber by Moffett and Dekkers [28]. In situ formation of graft copolymer can be obtained by the use of suitably functionalized rubbers. By the usage of conventional vulcanizing agents for EPDM, the dynamic vulcanization of the blend can be achieved. The optimum effect of compatibilization along with dynamic vulcanization can be obtained only when the compatibilization is done before the rubber phase is dispersed. 

Kresge E.N., Polyolefin thermoplastic elastomer blends. Rubber Chem. TechnoL, 64, 469, 1991. 

Table 15.13. Key properties of commercial thermoplastic elastomer blends based on polypropylene/elastomer dynamic vulcanizates...

Sometimes, the compatibilization of PP/EPDM blends has been the key issue to improve the properties of the blends. Lopez-Manchado s group (7) studied the effect of grafted PP on the compatibihty and properties of PP-EPDM thermoplastic elastomer blends. They functionalized the isotactic PP (iPP) through grafting in Brabender plasticorder with two itaconate. The functionalization of iPP was performed by melt blending through grafting with two itaconic acid derivatives, monomethyl itaconate and dimethyl itaconate (MMI and DMI, respectively). 

Because of low cost, high heat deflection temperature (HDT (104°C)), notched impact resistance, improved low temperature impact and flexibility, weather resistance, flame retardancy, and impact resistance, the PP/EPDM blend has got a widespread applications. These unique characteristics of this thermoplastic elastomer blend make it an attractive alternative to conventional elastomer in a variety of markets such as automobile industries, wire, cable insulator, automobile bumpers and fascia, hose, gaskets, seals, weather stripping, among others. 

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. 

S. Shahbikian, Phase Morphology Development and Rheological Behavior of Non-plasticized and Plasticized Thermoplastic Elastomer Blends (Ecole Polytechnique, Mraitreal, 2010),... 

ETP Polyamide/acrylic thermoplastic elastomer blend E. I. du Pont de Nemoiffs... 

Geolast Thermoplastic elastomer blends NBR/EPDM or PP/NBR blends Advanced Elastran. SysL... 

DYNAMICALLY PARTLY CURED THERMOPLASTIC ELASTOMER BLENDS... 

Table 8.6. Dynamically Partly Cured Thermoplastic Elastomer Blends ...

Uniroyal, Inc. see W. K. Fischer), Dynamically Partially Cured Thermoplastic Blend of Monoolefin Copolymer Rubber and Polyolefin Plastic, Br. Pat. 1,380,884 (1975). Dynamic partial cure of EPDM or EPM. Thermoplastic elastomers. Blend with polyethylene or polypropylene. Simultaneous blending and semicuring. 

Thermoplastic elastomers, blends, and filled polymers also show a superstructure consisting of different phases. These structures and their pronoimced... 

Isayev A I (1991) Composite thermoplastic elastomer blend and process for preparing the same, U.S. Patent 5,021,475, Can Patent 2,010,103 (1991). 

Blends of NR and ethylene-vinyl acetate copolymer (EVA) (physical blends and statically vulcanized) combine the good elastomeric and mechanical properties of NR with the excellent ageing and flex crack resistance of EVA. Blends of NR/EVA copolymer are becoming an important rubber/thermoplastic elastomer blend. Applications of these materials can be found in fields where... 

Natural RubberjEngineering Thermoplastic Elastomer Blends the mixer and then masticated NR is added. Additives such as compati-... 

Verma, G., et ai, PBT/thermoplastic elastomer blends - Mechanical, morphological, and rheological characterization. Polymer - Plastics Technology and Engineering, 47(10) p. 969. 2008. 

S Radhakrishnan, DR Saini. Structure and electrical properties of polypyrrole-thermoplastic elastomer blends. Polym Int 1994 34 111-117. 

Guo Q, Figueiredo P, Thomann R, Gronski W. Phase behavior, morphology and interfacial structure in thermoset/thermoplastic elastomer blends of polyfpropylene glycol)-type epoxy resin and polystyrene-b-polybutadiene. Polymer 2001 42 10101-10. 

SAXS and WAXS are particularly efficient in the study of amorphous polymers including microstructured materials, hence their use in block copolymers (see also Chapters 6 and 7). The advent of synchotron sources for X-ray scattering provided new information, particularly on the evolution of block copolymer microstructures with time resolution below one second. In particular, the morphology of TPEs is most often studied with these techniques Guo et al. [108] applied SAXS to the analysis of the phase behavior, morphology, and interfacial structure in thermoset/thermoplastic elastomer blends. WAXS is often associated with SAXS and some other methods, such as electron microscopy, and various thermal and mechanical analyses. It is mainly used in studies of the microphase separation [109,110], deformation behavior [111], and blends [112]. 

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