Polyether-polyester copolymers

The category of elastomers includes a wide range of products, such as natural rubber (NR), styrene-butadiene rubber (SBR), styrene-butadiene-styrene copolymer (SBS known as thermoplastic rubber), styrene-isoprene-styrene copolymer (SIS), polyurethane rubber, polyether-polyester copolymer, olefinic copolymers, ethylene-propylene rubber (EPR) and so on (see also Table 3.16). 

Bakker D, et al. Biocompatibility of a polyether urethane, polypropylene oxide, and a polyether polyester copolymer. A qualitative and quantitative study of three alloplastic tympanic membrane materials in the rat middle ear. J Biomed Mater Res 1990 24(4) 489-515. 

Bakker, D., van Blitterswijk, C. A., Hesseling, S. C., Koerten, H. K., Kuijpers, W., and Grote, J. J., 1990, Biocompatibility of a Polyether Urethane, Polypropilene Oxide, and a Polyether Polyester Copolymer. A Qualitative and Quantitative Study of three Alloplastic Tympanic Membrane Materials in the Rat Middle Ear. J. Biomed. Mater. Res. 24 489-515. 

Mody P C, Wilkes G L and Wagener K B (1981) Structure-property relationships of a new series of segmented polyether-polyester copolymers, J Appl Polym Sci 26 2853-2878. 

Chem. Descrip. Polyether-polyester copolymer Ionic Nature Nonionic Uses Detergent additive Features Soil release properties Properties Grans. 100% act. 

The polyols used are of three types polyether, polyester, and polybutadiene. The polyether diols range from 400 to about 10,000 g/mol. The most common polyethers are based on ethylene oxide, propylene oxide, and tetrahydrofuran or their copolymers. The ether link provides low temperature flexibility and low viscosity. Ethylene oxide is the most hydrophilic and thus can increase the rate of ingress of water and consequently the cure rate. However, it will crystallize slowly above about 600 g/mol. Propylene oxide is hydrophobic due to hindered access to the ether link, but still provides high permeability to small molecules like water. Tetrahydrofuran is between these two in hydrophobicity, but somewhat more expensive. Propylene oxide based diols are the most common. 

Weathering Many plastics has short lives when exposed to outdoor conditions. The better materials include acrylic, chlorotri-fluorethylene, vinylidene fluoride, chlorinated polyether, polyester, alkyd, and black linear poly-ethylene. Black materials are best for outdoor service. Some of the styrene copolymers are suitable for certain outdoor uses (Chapter 2, WEATHERING/ ENVIRONMENT). 

Poly(ether ester) (PEE) copolymers were consisted of soft segments of polyethers and hard crystalline segments of polyesters. Depending on the polyether/polyester ratio, PEE copolymers exhibit a wide range of mechanical behavior combined with solvent resistance, thermal stability, and ease of melt process ability. 

Multiblock copolymers are synthesized by step polymerization using prepolymers containing specific end-groups (Eq. 14). Polyester- and polyether-polyurethanes and polyether-polyesters are multiblock copolymers of commercial interest. Step polymerizations has advantages over living polymerization. There is a... 

Thermoplastic elastomeric behavior requires that the block copolymer develop a microheterogeneous two-phase network morphology. Theory predicts that microphase separation will occur at shorter block lengths as the polarity difference between the A and B blocks increases. This prediction is borne out as the block lengths required for the polyether-polyurethane, polyester-polyurethane, and polyether-polyester multiblock copolymers to exhibit thermoplastic elastomeric behavior are considerably shorter than for the styrene-diene-styrene triblock copolymers. 

The nature of the hard domains differs for the various block copolymers. The amorphous polystyrene blocks in the ABA block copolymers are hard because the glass transition temperature (100°C) is considerably above ambient temperature, i.e., the polystyrene blocks are in the glassy state. However, there is some controversy about the nature of the hard domains in the various multiblock copolymers. The polyurethane blocks in the polyester-polyurethane and polyether-polyurethane copolymers have a glass transition temperature above ambient temperature but also derive their hard behavior from hydrogen-bonding and low levels of crystallinity. The aromatic polyester (usually terephthalate) blocks in the polyether-polyester multiblock copolymer appear to derive their hardness entirely from crystallinity. 

Polyether-polyester polyol hybrids, 25 472 Polyetherimide-polysiloxane block copolymers, 24 698, 704, 708... 

Block copolymers such as styrene-butadiene-styrene (SBS) and its hydrogenated versions (SEBS), along with polyester-polyether block copolymers, can also be used to improve PBT impact. The SEBS and SBS copolymers [47], and especially their functionalized, grafted derivatives [48], show surprisingly good affinity for the polyester. 

Elastollan Polyurethane block copolymer with polyether/polyester BASF... 

Grilamid Polyamide copolymer with polyether/polyester nylon-12 EMS America Grilon... 

EMA copolymer Acrylic Polyester fiber Polyamide copolymer with polyether/polyester Epoxy and PVC powders Nylon-6 Acrylic fibers Poromeric film Vinyl Vinyl PVC... 

With very short "blocks", snch as in the random-copolymer SBR, there is only a very small difference in entropy between the segregated and the homogeneous condition no or hardly any change of entropy npon segregation. As the block length increases, this difference, however, increases, so that (G decreases (see MT 9.1.4). Segregation is, therefore, less complete in mnlti-block copolymers (such as polyethers- polyesters). 

Fig. 10. Internal energy changes as a function of deformation for oriented LDPE (I) and stress softened thermo-elastoplastic polyurethanes with 50% (2) and 42 % (3) hard phase content and polyether-polyester block copolymer with 48% hard phase content (4). The dotted curves 1 and 2 represent intramolecular energy changes for the corresponding polymers119 ...

Newer developments are polyester/polyether block copolymers (Hytrel, Amitel), etc. By choosing various levels of block length ratio, a broad spectrum of stiffnesses (or hardnesses) can be obtained, which practically fills the gap between rubbers and thermoplasts. TPE s form a rapidly growing class of materials, which find an increasing number of applications. 

Block copolymers characterised by different backbone structures of well-defined block lengths have been obtained from oxiranes and other heterocyclic monomers in the presence of catalysts that are effective at bringing about living polymerisations. Aida et al. [127,188,189,195,196] applied aluminium porphyrins and Teyssie et al. [125,197,198] applied bimetallic /i-oxoalkoxidcs for block copolymerisations in systems involving oxirane lactone, oxirane oxirane/cyclic acid anhydride, and oxirane/cyclic acid anhydride lactone as block forming units and obtained respective polyether polyester and polyester polyester block copolymers. Such copolymers seem to be of exceptionally wide potential utility [53]. 

Liggins, R.T. Burt, H.M. Polyether-polyester diblock copolymers for the preparation of paclitaxel loaded polymeric micelle formulations. Adv. Drug. Del. Rev. 2002, 54, 191-202. 

To prepare the graft copolymer, a PO (MW = 50 to 1,000 kg/mol) was either dissolved or swollen in an inert hydrocarbon, monomers (>80 wt% of a methacrylic ester, CH2=C(CH3)COOR) and an initiator was added to the heated mixture while stirring. As a result, acrylic branches of a relatively high molecular weight (MW = 20 to 200 kg/mol) were grafted onto the PO macromolecules. The graft copolymer could be used as a compatibilizer-cwm-impact modifier in a variety of polymers selected from between PO, acrylic polymers, SAN, EVAc, PA, PEST, PC, POM, PAr, PVC, ABS, PVDC, cellulosics, polyester-polyether block copolymers, PEA, PEEK, PEI, PES, CPVC, PVDF, PPE, PPS, PSF, TPU, PAI, PCL, polyglutarimide, blends of PEST with PC or PVC [Ilendra et al., 1992, 1993]. 

PBT with segmented polyester-polyether block copolymer The miscibility was found to depend on the copolymer composition Gallagher et al., 1993... 

The polycondensation of difunctional oligomers leads to the preparation of well-defined polymer structures. Monomers in this type of reactions must be soluble in the reaction mixture and stable when the reaction is carried out in the melt, which is the case for some aromatic polymers prepared by polycondensation [22]. As previously described, polycondensation can occur with monomers bearing the same or a different functional group at both ends of the molecule. When one of the reactive functional groups is a hydroxyl moiety, several types of materials can be prepared, such as polyethers, polyesters, and polyurethanes, independently if they are used to form homopolymers, copolymers, or hyperbranched polymers. 

The wide applicability of aluminum porphyrin initiators (1) leads to a variety of tailored block copolymers such as polymethacrylate-polyether and polymethacrylate-polye-ster, as well as polymethacrylate-polymethacrylate and polymethacrylate-polyacrylate, that can be synthesized by sequential living polymerization of the corresponding monomers.- For example, when 1,2-epoxypropane (11, R = Me) is added to a polymerization mixture of methyl methacrylate (21, R = Me) with la at 100% conversion of 21, the polymerization of 11 takes place from the enolate growing end (32 ) to give a narrow MWD polymethacrylate-polyether block copolymer having an alcoholate growing terminal (Table 4). Likewise, the aluminum enolate species (32 ) can also react with lactones (14,15), thereby allowing the formation of a poly(methyl methacrylate)-polyester block copolymer with narrow MWD. 

Solvent-based dispersions such as polyvinyl acetate. Polyurethane, polyesters, polyethers, acrylic copolymers, Rubber-based adhesives with tackifiers and plasticizers. 

The three major types of TPEs are block copolymers such as SEES (styrene-ethylene-butylene-styrene block copolymer) (Kraton by Kraton Polymer), polyether— polyester (Hytrel by DuPont), rubber/plasticblends (900 series Sumitomo Chemical), and dynamically vulcanized rubber/plastic alloys (Innoprene by Kumho Polychem, Santo prene by Exxon-Mobil, Sarlink by DSM, Unipene byTeknor Apex). Figure 3.28 shows the cost versus general performance comparison for different TPEs [31]. 

SEBS TPU (thermoplastic urethane) COPE (polyether-polyester block copolymer) TPO (thermo plastic olefin)/ TPV... 

Common SS include polyethers, polyesters and polyalkyl glycols with glass transition temperatures in the range of -70°to -30°C. Commonly used macrodiols in the PUs synthesis are polyalkyl-diols, such as polyisobutylene diol [70], polybutadiene (PBU) [20, 71], or oligo-butadiene diols [72] as well as hydrogenated polybutadiene diol [20] polyether diols polytetrahydrofuran (PTHF or PTMO) [50-52], polyethylene glycol (PEG) or (PEO) [73], polypropyleneoxide (PPO) [73] or mixed blocks of them PEO-PPO-PEO [74] and PPO-THF [54] polyester diols poly(ethylene adipate) (PEA) [4,20], poly(butylene adipate) (PBA) [20, 73], and latterly polycaprolactone diol (PCL or PCD) [75], polyalkylcarbonate polyol [20] or mixed blocks of them, for example poly(carbonate-co-ester)diol [76], poly(hexamethylene-carbonate)diol [77], as well as poly(hexamethylene-carbonate-co-caprolactone)diol [78] and a mixed block copolymer of polyether and polyester blocks PCL-b-PTHF-b-PCL [79]. Examples schemes of macrodiols are shown in Eig. 1.9. 

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