Polyether-amide copolymer

For some applications, such as trays of conveyer belts for electronic components, copiers and printers, or even artificial turf, more permanent antistats are desired. One approach is the use of polymers such as polyether amide copolymers or ethylene ionomers. Highly conductive graphite and metal fibers such as nickel fiber are also used to lower the resistivity of polymer articles [15]. For high performance materials that can tolerate the added cost impact, carbon nanotubes can also be used. 

Block copolymers can contain crystalline or amorphous hard blocks. Examples of crystalline block copolymers are polyurethanes (e.g. B.F. Goodrich s Estane line), polyether esters (e.g. Dupont s Hytrel polymers), polyether amides (e.g. Atofina s Pebax grades). Polyurethanes have enjoyed limited utility due to their relatively low thermal stability use temperatures must be kept below 275°F, due to the reversibility of the urethane linkage. Recently, polyurethanes with stability at 350°F for nearly 100 h have been claimed [2]. Polyether esters and polyether amides have been explored for PSA applications where their heat and plasticizer resistance is a benefit [3]. However, the high price of these materials and their multiblock architecture have limited their use. All of these crystalline block copolymers consist of multiblocks with relatively short, amorphous, polyether or polyester mid-blocks. Consequently they can not be diluted as extensively with tackifiers and diluents as styrenic triblock copolymers. Thereby it is more difficult to obtain strong, yet soft adhesives — the primary goals of adding rubber to hot melts. 

Tsubouchi and Yoshikawa [79] are concerned with pervaporation separation of benzene/cyclohexane mixtures using membranes based on polyamide/polyether block copolymers. It has been established that the separation factor increases with the increase in the polyamide component containing polar amide groups capable of forming hydrogen bonds e.g., the 1 1 block copolymer of polyamide 12 and polyoxyethylene has the benzene/cyclohexane separation factor /3p = 2.8 and the flux 2 = 300 g/m h a more rigid 3 1 polyamide 12/polyoxyethylene block copolymer has a much higher separation factor )8p = 5.0 and 2 = 80 g/m h. 

Newer materials are being developed which lie between plastics and elastomers. One of these is a polyether block amide copolymer developed by ATO Chemie, Europe, called Pebax. This is a tough, highly flexible material which by changing the ratio of ether and amide can have a wide balance between hardness and flexibility. Currently this material is relatively expensive ( 3,000- 5,000 per tonne). 

Important block copolymers include the styrene types (TPE-S), polyether esters (TPE-E), polyurethanes (TPE-U), and polyether amides (TPE-A). 

M. E. Rezac, T. John, P. Pfromm, Effect of copolymer composition on the solubility and dif-fusivity of water and methanol in a series of polyether amides, J. Appl. Polym. ScL, 65, 1983 (1997). 

Pebax polyether block amide copolymers consist of regular linear chains of rigid polyamide blocks and flexible polyether blocks. They are injection molded, extruded, blow molded, thermoformed, and rotational molded. 

Polyoltfin Polyester Polyether/ amide block copolymers Block copolymers of styrene and butadiene or styrene and ieoprene Block copolymere of styrene and ethylene and/or butylene Siliecne-based, pseudo-interpenetrating networks ... 

Several methods can be employed for the synthesis of polyether-6-amide copolymers. Though thermal polymerization is probably the most important one, the synthesis can also be carried out in solution or via an interfacial technique. Sometimes a combination of two methods may be required. The polymerization can also be carried out in one or two steps, and in one or two pots. Each method has its advantages and drawbacks, and the choice of the method will usually depend on the nature of the starting material. 

To the best of our knowledge, Imai et al. [50] were the first to investigate this technique for the synthesis of polyether-amides containing aromatic diamines. The polycondensation was successfully carried out in N-methyl-2-pyr-rolidone (NMP) at 100°C with triphenyl phosphite and pyridine in the presence of LiCl and CaCl2. Yamashita et al [51] attempted the synthesis of PA6.6-PEO segmented copolymers, but the yields were rather low. 

The thermal polymerization of polyamide and polyether segments with the formation of an amide link has been repeatedly described in the literature and numerous patents have been filed by companies, such as Toray Industries, Teijin Ltd., and Asahi Kasei. For instance, Kimura et al [58] successfully prepared a poly(ether-amide) copolymer by polymerizing the nylon 6.6 salt together with the isolated salt of a poly(oxyethylene) diglycolic acid and 1,6-diamino-hexane, at 270 °C for 5 h in vacuum. 

Pradet and co-workers [60] have presented an original preparation of polyether-6-amide copolymers using a chain-coupling reaction between 4,4 -disub-stituted bisoxazolones and a mixture of amine-terminated polyethers and polyamide oligomers (Figure 4). The reaction could be carried out in a one- or... 

Bouma K, Wester G A and Gaymans R J (2001) Polyether-amide segmented copolymers based on ethylene terephthalamide units of uniform length, J Appl Polym Sci 80 1173-1180. 

Alberola N (1988) Micromechanical properties of polyether block amide copolymers, J Appl Polym Sci 36 787-804. 

Faruque H S and Lacabanne C (1987) A thermally stimulated current technique for measuring the molecular parameters of Pebax, a polyether-block amide copolymer, J Mater Set 22 675-h78. 

Warner S (1990) Strain-induced crystallization and melting behavior of polyether-amide block copolymer, J Blast Plast 22 167-173. 

The fiber used in this study was Twaron 2200 a poly(p-phenylene terephthalamide) (PPTA) aramid fiber, supplied by Akzo Nobel Research (Arnhem). The fibers have modulus Ef= 136 GPa, tensile strength, thermoplastic elastomer, polyether amide block copolymer supplied by Atofma known commercially as Pebax . These thermoplastic elastomers (TPE) consist of linear chains of hard polyamide (PA) blocks covalently linked to soft polyether (PE) blocks via ester groups. The grade of Pebax used was Pebax 7033, with a modulus Eva. = 128 MPa, yield stress ay = 32 MPa, Yield strain ey = 25 %, ultimate failiue stress a m = 67 MPa and an ultimate strain e m = 400 %. 

Polyether block amides (PEBA) are block copolymers of ... 

MC MDI MEKP MF MMA MPEG MPF NBR NDI NR OPET OPP OSA PA PAEK PAI PAN PB PBAN PBI PBN PBS PBT PC PCD PCT PCTFE PE PEC PEG PEI PEK PEN PES PET PF PFA PI PIBI PMDI PMMA PMP PO PP PPA PPC PPO PPS PPSU Methyl cellulose Methylene diphenylene diisocyanate Methyl ethyl ketone peroxide Melamine formaldehyde Methyl methacrylate Polyethylene glycol monomethyl ether Melamine-phenol-formaldehyde Nitrile butyl rubber Naphthalene diisocyanate Natural rubber Oriented polyethylene terephthalate Oriented polypropylene Olefin-modified styrene-acrylonitrile Polyamide Poly(aryl ether-ketone) Poly(amide-imide) Polyacrylonitrile Polybutylene Poly(butadiene-acrylonitrile) Polybenzimidazole Polybutylene naphthalate Poly(butadiene-styrene) Poly(butylene terephthalate) Polycarbonate Polycarbodiimide Poly(cyclohexylene-dimethylene terephthalate) Polychlorotrifluoroethylene Polyethylene Chlorinated polyethylene Poly(ethylene glycol) Poly(ether-imide) Poly(ether-ketone) Polyethylene naphthalate Polyether sulfone Polyethylene terephthalate Phenol-formaldehyde copolymer Perfluoroalkoxy resin Polyimide Poly(isobutylene), Butyl rubber Polymeric methylene diphenylene diisocyanate Poly(methyl methacrylate) Poly(methylpentene) Polyolefins Polypropylene Polyphthalamide Chlorinated polypropylene Poly(phenylene oxide) Poly(phenylene sulfide) Poly(phenylene sulfone)... 

Other copolymers of polyamides include poly(glycols) sequences. Examples from this group are nylon 12-b/ock-poly(tetramethylene glycol) with the idealized formula -[NH-(CH2)ii-C(0)]x [-0-(CH2)4-O-]y and poly[(ethylene glycol)-co-1,6-hexanediamine-co-(methylpentamethylene diamine)-co-1,4-benzenedicarboxylic acid]. Pyrolysis of these copolymers generates a mixture of compounds, some typical for amides such as nitriles and some typical for polyethers. 

---