Esters thermoplastic

With the expiry of the basic ICI patents on poly(ethylene terephthalate) there was considerable development in terephthalate polymers in the early 1970s. More than a dozen companies introduced poly(butylene terephthalate) as an engineering plastics material whilst a polyether-ester thermoplastic rubber was introduced by Du Pont as Hytrel. Polyfethylene terephthalate) was also the basis of the glass-filled engineering polymer (Rynite) introduced by Du Pont in the late 1970s. Towards the end of the 1970s poly(ethylene terephthalate) was used for the manufacture of biaxially oriented bottles for beer, colas and other carbonated drinks, and this application has since become of major importance. Similar processes are now used for making wide-neck Jars. 

With these polymers hard blocks with T s well above normal ambient temperature are separated by soft bloeks which in the mass are rubbery in nature. This is very reminiscent of the SBS triblock elastomers discussed in Chapter 11 and even more closely related to the polyether-ester thermoplastic elastomers of the Hytrel type deseribed in Chapter 25. 

Veenstra H., Hoogvfiet R.M., Norder B., De B., and Abe P. Microphase separation and rheology of a semicrystalUne poly(ether-ester) multiblock copolymer, J. Polym. Sci. B. Polym Phys., 36, 1795, 1998. Garbrieelse W., SoUman M., and Dijkstra K., Microstmcture and phase behaviour of block copolyfether ester) thermoplastic elastomers. Macromolecules, 34, 1685, 2001. 

Zhu L.L. and Wegner G. The morphology of semicrystalUne segmented poly(ether ester) thermoplastic elastomers, Macromol. Chem., 182, 3625, 1981. 

Fakirov S, Fakirov C, Fischer EW, and Stamm M. Deformation behaviour of poly(ether ester) thermoplastic elastomers as revealed by SAXS. Polymer, 1991, 32, 1173-1180. 

Cellolyn . [Hercules] Esters thermoplastic resin used in lacquers, ink vehicles, varnishes, adhesives. 

Staybelite . [Hercules] Rosin derivs. or esters thermoplastic resin for adhesives tackifier, plasticizer, piooessii aid for rubbers, laminations, barrier coatings, chlorinated rubber finishes modifier for film-formers, elastomers, waxes sofiener/plasticizer for chewii gum. 

Zonester . [Arizona] Rosin esters thermoplastic resin, tackifier for rubber, adhesives, contact cements, coatings. 

Closely related to the polyether-ester thermoplastic elastomers are thermoplastic polyurethane elastomers, which consist of polyurethane or urethane terminated polyurea hard blocks, with Tg above normal ambient temperature, separated by soft blocks of polyol, which in the mass are rubbery in nature (see Section 4.11 for more details). The main uses of thermoplastic rubbers (e.g., Estane by Goodrich) are for seals, bushes, convoluted bellows, and bearings. 

MAJOR APPLICATIONS Molding plastic, molecular component of polyether ester thermoplastic block copolymer elastomer, fiber and plastic forming, used in tooth and paint brush and in bristles and filler fabrics. 

Aim TH, Park YH, Kim SH, Baik DH. Preparation and characterization of poly(ether ester) thermoplastic elastomers containing the 2,6-naphthalenedicarboxyl group. J Appl Polym Sci 2003 90(13) 3473-80. 

S. Fakirov, C. Fakirov, E. W. Fischer, M. Stamm and A. A. Apostolov, Reversible morphological changes in poly (ether ester) thermoplastic elastomers during deformation as revealed by SAXS, Colloid. Polym. Set., 271 811-823,1993. 

Vallance, M.A. and S.L. Cooper, Microstructure in linear condensation block copolymers A modeling approach. Macromolecules, 17(6) p. 1208.1984. Gabrielse, W., M. Soliman, and K. Dijkstra, Microstructure and Phase Behavior of Block Copoly(ether ester) Thermoplastic Elastomers. Macromolecules, 34(6) p. 1685. 2001. 

Wegner, G., et ai, Structure and properties of segmented polyether-esters. II. Crystallization behavior of polyether-esters with random distribution of hard segment length. Die Angewandte Makromolekulare Chemie, 74(1) p. 295.1978. Litvinov, V.M., et ai, Phase Composition of Block Copoly(ether ester) Thermoplastic Elastomers Studied by Solid-State NMR Techniques. Macromolecules, 36(20) p. 7598.2003. 

A typical product has a Mn of about 25 000-30 (KX). Whilst this is low compared with most conventional elastomers, the higher values used with these latter materials arises from the need to minimize the importance of non-loadbearing chain ends, a problem which does not arise in a block copolymer terminated by hard segments. A range of materials has been made available in which the proportion of hard segments is varied from about 33 to 85%. Polymers in which the hard blocks have been modified by the presence of tetramethylene-1,4-cyclohexane dicarboxylate have been supplied by Tennessee Eastman (Lilaonitkul and Cooper, 1977). Polyether-ester thermoplastic rubbers of undisclosed composition have also been supplied by AKU under the trade name Arnitel. 

Stribeck, N. and Fakirov, S. (2001) Three-dimensional chord distribution function SAXS analysis of 48 the strained domain stmcture of a poly(ether ester) thermoplastic elastomer. Macromdecules, 34, 7758-7761. 

Stribeck N and Fakirov S (2001) Three-Dimensional Chord Distribution Function SAXS Analysis of the Strained Domain Structure of a Poly(ether ester) Thermoplastic Elastomer, Macromolecules 34 7758-7761. 

The resin matrix is usually a formulated thermoset system (i.e. a reactive matrix, which on the application of heat and pressure, chemically reacts to form an infusible reinforced laminate). The thermosetting matrices are most often based on epoxy chemistries although there are plenty of examples of phenolic, bismaleimide and polyimide matrices (for example, the HexPly range from Hexcel Composites) and a few where the resin is based on cyanate esters. Thermoplastic matrices are also encountered (i.e. matrices that can change from a solidus to a liquidus form by tbe application of heat and pressure and then revert to the solid state on cooUng) which are usually, but not exclusively, based on polysulphone, polyetbersulphone or polyether ether ketone chemistries. 

Muramatsu S and Lando J B (1998) Reversible crystal deformation of poly(tetra-methylene terephthalate) segments in semicrystalline segmented poly(ether-ester) thermoplastic elastomers, Macromolecules 31 1866-1870. 

Deleens G, Foy P and Marechal E (1977) Synth e et caracterisation de copolyconden-sats sequences (polyamide-set ether) III Etude de la reaction de polycondensation du polyamide-11 oj,ui -dicarboxylique et du polyoxyethylene u>,u> -dihydroxy. Determination des constantes de vitesse et de I nergie d activation, Eur Polym J 13 353-360. McGarthy S J, Meijs G F and Gunatillake P (1997) S5mthesis, characterization and stability of poly[(alkylene oxide) ester] thermoplastic elastomers, J Appl Polym Sci 65 1319-1332. 

The observed phenomena result from dissolution of 4GT in PA12 and deterioration of the crystalline phase perfection. Analyzing the cooling scans, it can be noticed that the 4GT paracrystalline phase begins to form when the (4GT)x block has DP = 9, ie., when the molecular weight of this block becomes equal to that of the PA12 block two exothermal effects are observed on the thermogram (about the thermal properties of poly(ether ester) thermoplastic elastomers, see also Chapter 6). 

The thermal transitions and the relaxation processes observed in multiblock terpolymers allow to evaluate their phase morphology. At room temperature, these polymers are composed of three phases hard, soft, and strongly expanded interphase. The two latter phases are amorphous and form a matrix (continuous phase), whereas the hard (crystalline) phase is the dispersed phase. The thermal transition and relaxation processes occurring in the interphase of the multiblock copolymers are not detected by the DSC and DMTA methods. The incorporation of the third short block into the copolymer chain causes an increase in the volume of the interphase. This facilitates the establishment of the processes occurring in this phase at various temperatures. Moreover, it enables the evaluation of the influence of the dimension and composition of this phase on the polymer properties. (About the number of phases in poly(ether ester) thermoplastic elastomers, see also Chapter 6.)... 

Poly(Ether Ester) Thermoplastic Elatomers Phase and Deformation Behavior on the Nano- and Microlevel... 

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