Co-Polyester

A further approach is used by Bayer with their polyesteramide BAK resins. A film grade, with mechanical and thermal properties similar to those of polyethylene is marketed as BAK 1095. Based on caprolactam, adipic acid and butane diol it may be considered as a nylon 6-co-polyester. An injection moulding grade, BAK 2195, with a higher melting point and faster crystallisation is referred to as a nylon 66-co-polyester and thus presumably based on hexamethylene diamine, adipic acid and butane diol. 

Short fiber reinforcement of TPEs has recently opened up a new era in the field of polymer technology. Vajrasthira et al. [22] studied the fiber-matrix interactions in short aramid fiber-reinforced thermoplastic polyurethane (TPU) composites. Campbell and Goettler [23] reported the reinforcement of TPE matrix by Santoweb fibers, whereas Akhtar et al. [24] reported the reinforcement of a TPE matrix by short silk fiber. The reinforcement of thermoplastic co-polyester and TPU by short aramid fiber was reported by Watson and Prances [25]. Roy and coworkers [26-28] studied the rheological, hysteresis, mechanical, and dynamic mechanical behavior of short carbon fiber-filled styrene-isoprene-styrene (SIS) block copolymers and TPEs derived from NR and high-density polyethylene (HOPE) blends. 

Fluoroelastomers Novikova et al. [32] reported unproved physico-mechanical properties of fluoro mbbers by reinforcement with chopped polyamide fibers. Other fiber reinforcements are covered by Grinblat et al. [33]. Watson and Francis [34] described the use of aramid (Kevlar) as short fiber reinforcement for vulcanized fluoroelastomer along with polychloroprene mbber and a co-polyester TPE in terms of improvement in the wear properties of the composites. Rubber diaphragms, made up of fluorosilicone mbbers, can be reinforced using aramid fiber in order to impart better mechanical properties to the composite, though surface modification of the fiber is needed to improve the adhesion between fluorosUicone mbber and the fiber [35]. Bhattacharya et al. [36] studied the crack growth resistance of fluoroelastomer vulcanizates filled with Kevlar fiber. 

PET is produced continuously on a large scale as well as in small-sized batch plants. Currently, batch plants are mainly used for specialities and niche products. Batch plant capacities span the range from 20 to 60 t/d. Depending on process conditions, process technology and the desired PET grade, six to ten batches per day are commonly manufactured, each with a capacity of between 1.5 and 9.01. Batch plants are often designed as multi-purpose plants in which also PBT, PEN and different co-polyesters are produced. 

The SSP process allows polycondensation under gentle conditions to obtain the desired high molecular weights and excellent polymer quality for various applications. It can be successfully introduced for the production of sensitive co-polyesters as well as for the recovery of polyester waste. 

This present chapter will review the industrial relevance of the SSP process. In general, the representative production of PET is discussed, although the process can be used as a general example. Wherever particular differences are required for the production of other co-polyesters, these will be indicated. 

The above-mentioned results of the SSP of PET can be generally applied to other semicrystalline polyesters, such as poly(butylene terephthalate) (PBT), poly(tri-methylene terephthalate) PTT), polyethylene naphthalate) (PEN) or any other kind of semicrystalline co-polyester, as a result of their similar reaction behaviors. Most of the studies have been focused on PET and PBT due to their industrial importance. Meanwhile, the popularity of PEN is growing on account of the outstanding properties of this particular polymer. 

The SSP behavior of co-polyesters with rigid or voluminous comonomers, such as the flame retardant additive 9,10-dihydro[2,3-di-9-oxa-(2-hydroxyethoxy)-carbonylpropyl]-10-phosphaphenanthrene-10-oxide, or the ionic compound, sodium 5-sulfoisophthalate, is inhibited. This also occurs in the melt phase and cannot be improved by the use of catalysts [56], The results of studies examining the influence of employed catalysts with respect to stability and quality of the polymer suggest the use of antimony catalysts. The thermal or thermo-oxidative stability is, however, reduced by the interaction of the catalyst with the carboxylic groups of the polymer [57],... 

The basic knowledge of the principles of SSP usually allows a generalization concerning the production of any kind of semicrystalline polyester or co-polyester. Differences regarding the reactivities are observed which are attributed to the mobilities of the components employed, e.g. PEN, cationic dyeable polymers or flame-retardant co-polyesters. 

The SSP of PEN and co-polyesters based on 2,6-naphthalene dicarboxylic acid requires prolonged reaction times, which is obviously related to the rigidity of the monomers and therefore to both the reduced mobilities of the end groups and diffusion. Only a few detailed reports exist in the literature on this subject [31, 32], It should be noted that the analysis of PEN can become complicated due to its reduced solubility. 

An additional example of applying SSP to co-polyester production has been outlined in a US patent [59], This discloses the production of co-polyesters based on terephthalic acid and with up to 12% bis-(hydroxy ethoxy phenyl)sulfone co-monomer content. Additional patents exist concerning the SSP of other copolyesters [60, 61]. 

TPEE or COPE ThermoPlastic Ester Elastomer or CO-PolyEster SBC Styrenic Block Copolymer... 

Lou X, Detrembleur C, Lecomte P, Jerome R (2002) Controlled synthesis and chemical modification of unsaturated aliphatic (co)polyesters based on 6,7-dihydro-2(3H)-oxepinone. J Polym Sci A Polym Chem 40 2286-2297... 

Latere J-P, Lecomte P, Dubois P, Jerome R (2002) 2-Oxepane-l,5-dione a precursor of a novel class of versatile semicrystalline biodegradable (co)polyesters. Macromolecules 21 7857-7859... 

Blanquer S, Tailhades J, Darcos V, Amblard M, Martinez J, Nottelet B, Coudane J (2010) Easy synthesis and ring-opening polymerization of 5-Z-Amino-8-valerolactone new degradable amino-functionalized (co)polyesters. J Polym Sci A Polym Chem 48 5891-5898... 

Keywords (Co)polyesters Lipase Mechanism Polycondensation Ringopening polymerization... 

Edgar, O. B., and E. Ellery Structure-property relationships in polyethylene terephthalate co-polyesters. Part. I. Melting points. Part II. Second-order transition temperatures, J. Chem. Soc. (London) 1952, 2633—2643 J. Polymer Sci. 8, 1—22 (1952). 

Ferrocene-containing co-polyesters, preparation, 12, 350 Ferrocene-containing liquid crystals dendrimers, 12, 235 disubstituted ferrocenes, 12, 227 hydrogen-bonded ferrocene derivatives, 12, 234 monosubstituted ferrocenes, 12, 222 polycatenar ferrocenes, 12, 234 properties, 12, 221... 

Welsh, G.E., Blundell, DJ. and Windle, A.H. (1998) A transient liquid crystalline phase as a precursor for crystallization in random co-polyester fibers, Macromol. 31(5), 7562-7565... 

At the same time, prices for the three major types of bio-based resins, starch-based biopolymers, polylactic acid (PLA) and aliphatic aromatic co-polyester, have dropped considerably over the last... 

In 2003, the average price of starch blends was around 3.0-5.0 per kg. In 2005, the average price range of starch blends was down to 1.5-3.5 per kg. PLA is now being sold at prices between 1.37-2.75 per kg compared to a price range of 3.0-3.5 per kg three years ago, and is now almost price competitive with PET. The average cost of an aliphatic aromatic co-polyester has fallen from 3.5-4.0 per kg in 2003 to 2.75-3.65 per kg in 2005. Prices are expected to fall further for all biodegradable polymer types over time as production volumes increase and unit costs fall. 

Synthetic biodegradable polymers such as aliphatic-aromatic co-polyesters. 

For conventional technical applications aromatic polyesters such as polyethylene terephthalate (PET) and polybutylene terephthalate (PBT) are widely used. But these polymers are biologically inert and thus not directly applicable as biodegradable plastics. Combining both the excellent material properties of aromatic polyesters and the potential biodegradability of aliphatic polyesters has led to the development of a number of commercially available aliphatic-aromatic co-polyesters over the last decade or so. 

BASF s Ecoflex is based on a co-polyester from terephthalic acid, adipic acid and 1,4-butanediol. The content of terephthalic acid in the polymer is approximately 42-45 mol% (with regard to the dicarboxylic monomers). Modification of the basic co-polyester lead to a flexible material, which is especially suitable for film applications. 

EnPol from Korea s IRe Chemicals are based on a group of aliphatic co-polyesters comprising adipic acid, succinic acid, 1,2-ethanediol or 1,4-butanediol. EnPol polymers meet the specifications of the US Food Drug Administration for food contact applications and the USP specifications for medical device applications. 

The biodegradation of EnPol polymers was tested in a controlled laboratory composting test and showed that within 45 days a carbon dioxide evolution of more than 90% of the carbon present in the co-polyester was detected. 

The major classes of biopolymer, starch and starch blends, polylactic acid (PLA) and aliphatic-aromatic co-polyesters, are now being used in a wide variety of niche applications, particularly for manufacture of rigid and flexible packaging, bags and sacks and foodservice products. However, market volumes for biopolymers remain extremely low compared with standard petrochemical-based plastics. For example, biopolymer consumption accounted for just 0.14% of total thermoplastics consumption in Western Europe for 2005. 

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