Terpolymer thermoplastic polyurethane

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)... 

The major polymers with whieh PVC ean be alloyed are aerylonitrile-butadiene eopolymers, aerylonitrile-butadiene-styrene terpolymer, ethylene-vinylacetate copolymers, chlorinated polyethylene, chlorosulfonated polyethylene, thermoplastic polyurethanes, acrylics and methacrylics, and polycaprolactone. Table 18 lists the property enhancements achieved by blending these polymers with PVC. 

Figure 22.9 Visualization of compatibilizer location in immiscible blends SEM micrographs of a blend of thermoplastic polyurethane (TPU) with 20 wt% polypropylene compatibilized with different ethylenic co- and terpolymers (blend melt mixed using ZSK 30 extruder). The TPU matrix was selectively dissolved in dimethyl formamide and the remaining PP particles without or with compatibilizer were separated on a membrane. Wallheinke et al. [58]. Reproduced with permission of Elsevier.

The viscoelastic properties of semi-IPNs based on a thermoplastic polyurethane (TPU) and a chemically crosslinked polyurethane (PU network) formed in the TPU solution, as well as of the same semi-IPNs filled with " (-Fe203 powder have been studied by Brovko et al. [27]. The TPU (molar mass 40000 g/mole) was synthesized from poly (1,4-butylene) glycol adipate (molar mass 1000 g/ mole), 4,4 -methylenebis(phenyl isocyanate) and 1,4-butane diol as a chain extender. The PU network was based on a vinyl chloride/vinyl acetate/vinyl alcohol terpolymer with an adduct of 1,1,1-trimethylolpropane and 2,4-toluene diisocyanate the appropriate for crosslinking NCO/OH ratio was chosen to be 0.55. The non-filled semi-IPNs exhibited only one situated between those of TPU and PU network. Therefore, the components of the semi-IPNs may be assumed to be compatible. It was found that the semi-IPNs filled with a small amount of >Fe20g (up to 1.4 vol%) exhibited one shifted toward higher... 

Different types of polymers can be used to plasticize PVC compositions. For example, nitrile mbber (NBR), thermoplastic polyurethane, and ethylene vinyl acetate(EVA) co- and terpolymers can be used to alloy with PVC. These types of compositions are discussed in Chapter 15. This section will focus on the class of polyesto polymeric plasticizers. These have average molecular weights ranging from less than 1000 to about 25,000, and are viscous liquids to semisolids at room temperature. 

Polyurethane elastomers (some TUP, thermoplastic polyurethane) These terpolymers can be used uncured for most applications however, selected grades can be eross-linked to enhance properties. As a family these elastomers are tough and wear resistant. They have excellent chemical resistance and flexibility. They can have excellent clearity. Applieations include cable jackets. Automotive fascia, connectors, fittings, and many, many more. Ethylene-Propylene-Dlene Terpolymers (EPDM) These terpolymers typically contain a few percent of a diene such as hexadiene. This material is easy to fabricate and then is usually heat-treated at 125"C to 175 C to induce crbss-linking. The physical properties are much different after crosslinking. Commonly, they are heavily formulated for applications which include wire jacketing systems, automotive hoses, and roof sheeting. 

Ethylene/propylene/dicyclopentadiene terpolymer Ethylene-propylene-ethylidene norbornene elastomer, adhesives Epichlorohydrin elastomer Epichlorohydrin/ethylene oxide/allyl glycidyl ether terpolymer Epichlorohydrin/ethylene oxide copolymer Polyisoprene Polyurethane, thermoplastic... 

Thermoplastic elastomers that are formulated into hot-melt adhesives include polyurethane and block terpolymers, such as styrene-butadiene-styrene styrene-iso-prene-styrene and styrene-olefin-styrene, in which the olefin component is typically ethylene, propylene, and/or butylene. The saturation in the mid-segment of these terpolymers results in better UV and thermooxidative resistance than that of unsaturated butadiene and isoprene midsegments. 

In general, thermoplastic elastomer hot-melt adhesives are not as strong as polyesters. However, they exhibit good flexibility, high elongation, toughness, and vibration resistance. Polyurethanes and block terpolymers are used as hot-melt pressure-sensitive adhesives in tapes and labels and for nonwoven applications. 

Note PP polypropylene PS polystyrene PVC poly(vinyl chloride), POs polyolefins TPE thermoplastic elastomers PU polyurethane PA polyamides ABS acrylonitrile-butadiene-styrene terpolymer LDPE low density polyethylene. 

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