Copolyester TPE

Copolyester TPE is a high-cost elastomer but has above-average performance. Plasticisers are not used when forming copolyesters. This makes them purer than most TPE, which consequently makes them especially well suited for medical and food applications. Typical applications include fuel tanks, drive belts and cables. 

Like most elastomers, copolyesters can be bonded with cyanoacrylates and in these trials [2] no improvement was gained by using the primer (Table 4.2). 

Notes All shear strengths are given as guidelines only and may vary considerably depending on grade of rubber, fillers, surface finish, etc. 

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A route to compatibility involving ionomers has been described recently by Eisenberg and coworkers [250-252]. The use of ionic interactions between different polymer chains to produce new materials has gained tremendous importance. Choudhury et al. [60] reported compatibilization of NR-polyolefin blends with the use of ionomers (S-EPDM). Blending with thermoplastics and elastomers could enhance the properties of MPR. The compatibility of copolyester TPE, TPU, flexible PVC, with MPR in aU proportions, enables one to blend any combination of these plastics with MPR to cost performance balance. Myrick has reported on the effect of blending MPR with various combinations and proportions of these plastics and provided a general guideline for property enhancement [253]. 

TPEs are not listed in packaging statistics there are only specific uses for thermoplastic styrenics (TPS), copolyester TPEs (COPE) and polyether bloc amides (PEBA) in tearproof films, and for TPOs and TPVs in seals, etc. 

Film Processing Methods Copolyester TPE can be extruded into blown or cast Ecdel Elas-... 

Film Applications Copolyester TPE film and coating markets divide into breathable and non-breath-able applications.f ]... 

Permeability Copolyester TPE films and coatings are permeable to moisture and gases (O2 and CO2) but are non-porous and thus impermeable to water, blood, and bacteria.[ ... 

Gary Fairley and Jim Conkey DSM Engineering Plastics, Copolyester TPE Film, Plastics Technology Online, Gardner Publications Online, 2002. (http //www.plasticstechnology.com/articles/ 200012fa2.html)... 

Ester-Ether Block Copolymers [Copolyester TPEs (COPs)]. Ester-ether block copolymer TPEs, also called copolyester TPEs, are segmented block copolymers with the -A-B-A-B- structure, where A and B are alternating hard and soft polymeric segments connected by ester linkages. A general chemical structure can be expressed as follows ... 

TPUs can be made much softer than can the copolyester TPEs—down to a Shore A hardness of 50. The properties of TPU TPEs are largely determined by the ratio of the amounts of hard to soft phases, the length and length distribution of the segments, and the crystallinity of the hard segments. 

TPUs are polar materials and are therefore resistant to nonpolar organic fluids such as oils, fuels, and greases, but they are readily attacked and even dissolved by polar organic fluids such as dimethylformamide and dimethylsulfoxide. TPUs behave like copolyester TPEs toward water and aqueous solutions, being resistant to these media except at very high or low pH. Polyether TPUs are more resistant to such hydrolytic degradation than are the polyester TPUs. 

TPEs associating both rigid and soft polyester blocks have also been described. They cannot be obtained by the melt polyesterification used for polyesterether TPEs, since interchange reactions would yield random—rather than block — copolyesters. The preferred method involves the reaction of OH-terminated aliphatic and aromatic-aliphatic polyesters with chain extenders such as diisocyanates and results in copoly(ester-ester-urethane)s. 

There are two classes of polyolefin blends elastomeric polyolefin blends also called polyolefin elastomers (POE) and nonelastomeric polyolefin blends. Elastomeric polyolefin blends are a subclass of thermoplastic elastomers (TPEs). In general, TPEs are rubbery materials that are processable as thermoplastics but exhibit properties similar to those of vulcanized rubbers at usage temperatures (19). In TPEs, the rubbery components may constitute the major phase. However, TPEs include many other base resins, which are not polyolefins, such as polyurethanes, copolyamides, copolyesters, styrenics, and so on. TPEs are now the third largest synthetic elastomer in total volume produced worldwide after styrene-butadiene rubber (SBR) and butadiene mbber (BR). 

Most TPEs fall in one of six categories, listed in order of increasing cost and performance styrenic block copolymers, polyolefin blends (TPOs), elastomeric alloys, thermoplastic polyurethanes (TPUs), thermoplastic copolyesters, and thermoplastic polyamides [3]. 

Polyurethanes show many of the same features as the copolyesters and copolyamides with respect to both hard and soft segment crystallinity. One substantial difference between polyurethanes and the previous two matmals is that not all commercial polyurethane TPEs show hard segment crystallinity MDI-based polyurethanes show crystallinity while TDI-based urethanes do not. 

The chemical resistance of many TPEs is poor compared to that of conventional mbbers. Polyurethanes, copolyesters, and copolyamldes are very susceptible to oxidation, especially at elevated temperatures. Antioxidants and other additives are added to commercial products to improve the chemical resistance of these materials. Carbon black can be added to improve stability to UV light if the color of the material is unimportant. Hydrolytic stability is poor for the polyester-based polyurethanes and the copolyamldes because the ester linkage can be attacked by water. For all TPEs, certain organic solvents can degrade these materials if one or both of the blocks will dissolve in the particular solvent. The resistance to many common oils and greases is high for the more polar TPEs. 

General Description Amitel is DSM Engineering Plastics family of copolyesters (COPEs) and thermoplastic elastomers (TPEs). These resins are multiblock copolymers in which butylene terapthalate hard segments andpoly(alkylene oxide) soft segments alternate repeatedly along the polymer backboned 1... 

Apec KU 1-9320 f[Bayer AG http //WWW. bayer-ag. de, http //www. bayer. com] Polyester elastomer, thermoplastic Synonyms COPE Copolyester elastomer thermoplastic Copolyester, thermoplastic elastomer TPE-E... 

Thermoplastic elastomers (TPEs) continue to grow in commercial importance. These materials combine the functional properties of comparable thermoset elastomers with the fabrication advantages of thermoplastics. As a class, TPEs comprise several types of materials such as elastomeric alloys (EAs), styrenic block copolymers, copolyesters, and thermoplastic polyurethanes. 

Polyurethanes show many of the same features as the copolyesters and copolyamides with respect to both hard and soft segment crystallinity. One substantial difference between polyurethanes and the previous two materials is that not all commercial polyurethane TPEs show hard segment crystallinity MDI-based polyurethanes show crystallinity while TDl-based urethanes do not. Two crystalline structures have been found for MDl-BD hard segments in the unoriented state with another distinct form found in the oriented state [86,87]. Other studies have examined the effect of chain extender length on the crystal structure [88]. The differences between polyurethanes with chain-folded and chain-extended hard segment crystalhtes has been extensively studied by Eisenbach et al. [89]. 

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