EPDM/polypropylene

Coran, A.Y. and Patel, R. Rubber-thermoplastic compositions. Part I. EPDM-polypropylene thermoplastic vulcanizates. Rubber Chem. TechnoL, 5, 141, 1980. 

Styrene-butadiene-styrene (SBS) Styrene-ethylene-butadiene-styrene (SEBS) Ethylene-vinyl acetate/polyvinylidene chloride (EVA/PVDC) Thermoplastic polyurethane (TPU) Polyetherblock polyamide (PEBA) Copolyester, Polyetherester (TEEE) Polypropylene/ethylene- propylene terpolymers (PP-EPDM) Polypropylene/nitrile rubber (PP-NBR)... 

Thermolan 3000 EPDM/polypropylene blends Mitsubishi Petrochem. 

Equipment/tool design, construction, and processing of TPVs differ from that of other thermoplastics. EPDM/polypropylene is thermally stable up to 500°F (260°C) and it should not be processed above this temperature. It has a flash ignition temperature above 650°F (343°C). 

Advanced Elastomer Systems L.P. (AES) is the beneficiary of Monsanto Polymers TPE technology and business, which included Monsanto s earlier acquisition of BP Performance Polymers partially vulcanized EPDM/polypropylene (TPR), and Bayer s partially vulcanized EPDM/polyolefin TPEs in Europe. 

DJ Synnott, DF Sheridan, EG Kontos. EPDM-polypropylene blends. In SK De and AK Bhowmick, eds. Thermoplastic Elastomers from Rubber-Plastic Blends. Chichester Ellis Horwood, 1990, pp 130-158. 

Typical data are shown in Table 8.6 showing the effect of varying the peroxide level. An 80/20 EPDM/polypropylene mix was processed for seven minutes at 360 F in each experiment. The peroxide employed was 2,5-bis( er -butyl(peroxy))-2,5-dimethylhexane. 

Examples of these products are dynamically cured EPDM-polypropylene and chlorinated ethylene copolymer TPE s recently introduced by Monsanto and Du Pont under the tradenames SANTOPRENE and ALCRYN . These new products are opening up new application areas for TPE s by providing low cost, direct substitutes for medium performance thermoset rubbers. Work in this product area is expanding rapidly and many new products are expected to be introduced in the near future. 

Ellul [27] subjected EPDM/polypropylene and natural rubber/polypropylene blends to various halogenation treatments, namely fluorine/carbon dioxide, sodium hypochlorite/ acetic acid and bromine water. With the natural rubber blend, there was a substantial uptake of fluorine, chlorine and bromine in the surface regions as indicated by energy dispersive X-ray analysis and with all three pre-treatments the adhesion to an acrylic tape was greatly enhanced. In contrast, with the EPDM blend, fluorine was the only reagent which reacted with the rubbers and only this treatment resulted in a significant increase in adhesion to the acrylic tape. The above results can be explained in terms of the different concentrations of carbon-carbon double bonds in the two blends. Substantial incorporation of chlorine and bromine could occur with the natural rubber-polypropylene blend but not with the EPDM blend. However, fluorine gas will react readily with saturated hydrocarbons [28,29] and therefore the incorporation of fluorine into the EPDM blend is not surprising. 

LOW HARDNESS EPDM/POLYPROPYLENE THERMOPLASTIC DYNAMIC VULCANIZATES. I. PREPARATION TECHNOLOGY BY A TWIN-SCREW EXTRUDER... 

The use of TAG as a curing agent continues to grow for polyolefins and olefin copolymer plastics and mbbers. Examples include polyethylene (109), chlorosulfonated polyethylene (110), polypropylene (111), ethylene—vinyl acetate (112), ethylene—propylene copolymer (113), acrylonitrile copolymers (114), and methylstyrene polymers (115). In ethylene—propylene copolymer mbber compositions. TAG has been used for injection molding of fenders (116). Unsaturated elastomers, such as EPDM, cross link with TAG by hydrogen abstraction and addition to double bonds in the presence of peroxyketal catalysts (117) (see Elastol rs, synthetic). 

Considerable amounts of EPM and EPDM are also used in blends with thermoplastics, eg, as impact modifier in quantities up to ca 25% wt/wt for polyamides, polystyrenes, and particularly polypropylene. The latter products are used in many exterior automotive appHcations such as bumpers and body panels. In blends with polypropylene, wherein the EPDM component may be increased to become the larger portion, a thermoplastic elastomer is obtained, provided the EPDM phase is vulcanked during the mixing with polypropylene (dynamic vulcani2ation) to suppress the flow of the EPDM phase and give the end product sufficient set. 

The RIM process was originally developed for the car industry for the production of bumpers, front ends, rear ends, fascia panels and instrument housings. At least one mass-produced American car has RIM body panels. For many of these products, however, a number of injection moulding products are competitive, including such diverse materials as polycarbonate/PBT blends and polypropylene/EPDM blends. In the shoe industry the RIM process has been used to make soling materials from semi-flexible polyurethane foams. 

A manufacturer considering using a thermoplastic elastomer would probably first consider one of the thermoplastic polyolefin rubbers or TPOs, since these tend to have the lowest raw polymer price. These are mainly based on blends of polypropylene and an ethylene-propylene rubber (either EPM or EPDM) although some of the polypropylene may be replaeed by polyethylene. A wide range of blends are possible which may also contain some filler, oil and flame retardant in addition to the polymers. The blends are usually subject to dynamic vulcanisation as described in Section 11.9.1. 

BioProcess stainless-steel columns are fixed bed height columns designed for the most stringent requirements in the routine production of biopharmaceuticals. Wetted materials include stainless steel, polypropylene, and EPDM. The BPSS series may be operated at pressures up to 3 bar (0.3 MPa) and are supplied with sanitary fittings of 10 or 22 mm i.d. The available column sizes and specifications for the BPSS column series are given in Table 2.18. 

TPEs from blends of rubber and plastics constitute an important category of TPEs. These can be prepared either by the melt mixing of plastics and rubbers in an internal mixer or by solvent casting from a suitable solvent. The commonly used plastics and rubbers include polypropylene (PP), polyethylene (PE), polystyrene (PS), nylon, ethylene propylene diene monomer rubber (EPDM), natural rubber (NR), butyl rubber, nitrile rubber, etc. TPEs from blends of rubbers and plastics have certain typical advantages over the other TPEs. In this case, the required properties can easily be achieved by the proper selection of rubbers and plastics and by the proper change in their ratios. The overall performance of the resultant TPEs can be improved by changing the phase structure and crystallinity of plastics and also by the proper incorporation of suitable fillers, crosslinkers, and interfacial agents. 

Antony P., Bandyopadhyay S., and De S.K., Thermoplastic elastomers based on ionomeric polyblends of zinc salts of maleated polypropylene and maleated EPDM rubber, Polym. Eng. Sci., 39, 963, 1999. Weiss R.A., Sen A., Pottick L.A., and Willis C.L. Block copolymer ionomers. Thermoplastic elastomers possessing two distinct physical networks, Polym. Commun., 31, 220, 1990. 

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