Aliphatic aromatic polyester

Aliphatic-aromatic copoly imides, 268 Aliphatic-aromatic polyesters, 18, 19 Aliphatic degradable polyesters, 41 Aliphatic diacids, polyamide synthesis from, 183-184... 

Ecoflex A Completely Biodegradable Aliphatic-Aromatic Polyester. 104... 

Ecoflex ES was commercialized by BASE in 2010 as a compound with poly(lactic acid) (PEA) (Ecovio ES see Sect. 4.2.2). Ecoflex ES is an aliphatic-aromatic polyester with a similar structure to that of Ecoflex E (see Eig. 3). However, through exchanging one of the monomers with a monomer derived from plant oil, the new Ecoflex ES is partly based on renewable resources. 

Both Ecoflex and Ecovio are protected by various patents. The aliphatic-aromatic polyester PBAT is protected by its composition (EP-B 736557) and chain extension process (EP-B 792309, EP-B 809664, EP-B 809666, EP-B 1074570). 

The Ecovio patent portfolio covers the composition of compounds based on all aliphatic-aromatic polyesters and different compound partners (e.g., PLA) and branching agents, including different applications (EP-B 1656423, EP-B 1838784, EP-B 1204700, EP-A 2121838). 

Yamamoto M, Witt U, Skupin G, Beimbom D, Muller RJ (2002) Biodegradable aliphatic-aromatic polyesters Ecoflex. In Doi Y, Steinbiichel A (eds) Biopolymers, vol 4. Wiley-VCH, Weinheim, p 11... 

Crystalline polymers exhibit the following basic properties They are opaque as long as the size of the crystallites or spherulites, respectively, lies above the wavelength of light. Their solubility is restricted to few organic solvents at elevated temperature. The following crystalline polymers have attained technical importance as thermoplastic materials polyethylene, polypropylene, aliphatic polyamides, aliphatic/aromatic polyamides, aliphatic/aromatic polyesters, poly-oxymethylene, polytetrafluoroethylene, poly(phenylene sulfide), poly(arylene ether ketone)s. 

The price of synthetic biodegradable polymers has come down a little during the last three years. In 2003, for example, the average price of Eastar Bio and BASF s Ecoflex was around 3.5-4.0 per kg. In 2005, the average cost of an aliphatic aromatic polyester biopolymer was between 2.75-3.65 per kg. The more specialised polymers, such as DuPont s Biomax, cost as much as 5-6 per kg. Polycaprolactones cost between 4-7 per kg. Synthetic biodegradable polymer prices are expected to fall further over time as production volumes increase and unit costs fall further. 

Degradation Products of Aliphatic and Aliphatic-Aromatic Polyesters... 

In 1977, Tokiwa and Suzuki reported that some lipases, which are extracellular enzymes that usually cleave esters in oils and fats, are also able to attack ester bonds in some aliphatic polyesters and can depolymerize such materials [38]. Aliphatic polyesters, however, exhibit only limited useful properties for many applications. Aromatic polyesters, such as PET and PBT, which are widely applied because of their excellent properties, are not attacked by hydrolytic enzymes. This led to the development of aliphatic-aromatic polyesters as biodegradable plastics that present a compromise between biodegradability and material properties [39]. Recently, however, Muller et al. [40] have isolated a hydrolase (TfH) from Thermofibida fusca which is able to depolymerize the aromatic polyester PET at a high rate in contrast to other hydrolases such as lipases. They have demonstrated for the first time that commercial PET can be effectively hydrolyzed by an enzyme at a rate that does not exclude a biological recycling of PET. The effective depolymerization of PET with the enzyme TfH will result in water... 

Uses PU intermediate for adhesives, coatings, and cast elastomers Features Mixed aliphatic/aromatic polyester polyol with all primary hydroxyl functionality the aromatic acid lends hardness and heat resist. Properties Gardner 4 solid m.w. 3200 dens. 10.2 Ib/gal vise. 8500 cps (60 C) acid no. 1.0 hyd. no. 35 Lexorez 3130-120 [Inolex]... 

Moreover, inter- and intramolecular ester exchange reactions causing rearranged polyester sequences at the pyrolysis stage were also demonstrated to take place for aliphatics and aliphatic-aromatic polyesters" using Py-MS. 

Among the high molecular weight aliphatic-aromatic polyesters, the highest commercial volume material is poly(ethylene terephthalate). Most of it is prepared from dimethylene terephtha-late and ethylene glycol by a transesterification reaction ... 

These effects were caused by the compact structure of the molecules [142] hindering the interactions with the inner OH-groups. An even stronger H-bonding effect was identified for aliphatic-aromatic polyesters after thermal treatment, when a complete incorporation of the functional groups [143] into the H-bond network was demonstrated this was ascribed to the rather stiff and open structure of the polymers [112]. The controlled decrease of the molar amount of the end groups led to a significant reduction of this effect, however [111]. 

Statistical DB values were found for aU samples, with a marginal increase in the DB in line with the molar mass. A larger increase in the DB at higher DP-values was identified after the fractionation of an aliphatic-aromatic polyester [155] this finding was in agreement with previous kinetics studies on the one-pot melt polycondensation of this type of ahphatic-aromatic polyester performed by Schmaljohann et al. [30] Consequently, in these samples the coexistence of two different distributions was proven, namely molar mass and DB. It should be taken into account that, in contrast to the one-pot synthesis of the hb poly(ether amide)... 

Figure 24.12 KMHS exponent dependence on the degree of branching for two types of aliphatic-aromatic polyesters synthesized by copolycondensation of AB2 -h AB monomers (open squares) [111] and by...

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