Aliphatic long-chain polyesters

As a result of the DuPont patents for nylon, in 1937 Whinfield and Dickson, of the Calico Printers Association in England, became interested in polyesters based on aromatic dicaiboxyhc acids and ethylene glycol. Carotheis had, of course, abandoned his own early work following the disappointing results with aliphatic dicarboxylic acids. Whinfield and Dickson quickly produced a long-chain polyester and decided to patent the discoveiy, which was eventually licensed to ICI. The patent was actually granted in 1941 and ICl built the first commercial production unit in late 1954. ... 

BASF s Ecoflex and Novamont s Eastar Bio Ecoflex are aromatic-aliphatic co-polyesters based on butanediol, adipic acid, and terephthalic acid. BASF s products contain long-chain branching while Eastar Bio is highly linear in structure. 

Polyesters containing long-chain unbranched glycols have the highest impact strength. This property also increases with the increase in the chain length of aliphatic acids. 

Chem. Descrip. Sat., aliphatic, linear, hydroxyl-terminated diol based on a long chain glycol and polyesters... 

Naturally occurring miscellaneous polymers, such as shellac, a resin secreted by the lac insect. This is a complex crosslinked polyester of 9,10,16-trihydroxy-exadecanoic acid (aleuritic acid). The structure also includes some unsaturated long-chain aliphatic acids together with other compounds. ... 

The other hpid polymer, suberin, is a heteropolymer, consisting of an aliphatic polyester associated with cross-linked polyaromatics and embedded waxes. Upon transesterification of suberin, the monomers released include C16-C28 m-hydroxy fatty acids and C16-C26 ct, -dicarboxyhc acids, the latter of which are diagnostic monomers, unsubstituted very-long-chain fatty acids (VLCFAs C>i8) and alcohols, glycerol and ferulate. Usually the major components of suberin are -hydroxy derivatives of palmitic and/or oleic acids, but in some cases oo-hydroxy C220 also is a dominant component [37]. Dicarboxylic FAs derived from further oxidation of the -hydroxy-FAs are also found in suberin. 

Elastoester "A manufactured fiber in which the fiber-forming substance is a long-chain synthetic polymer composed of at least 50% by weight of aliphatic polyether and at least 35% by weight of polyester, as defined in 303.7(c)." ... 

In recent years, Novamont developed a family of aliphatic-aromatic copolyesters with its aliphatic dicarboxylic acid component predominantly based on long chain dicarboxylic acids of natural origin (sebacic acid, azelaic acid and brassylic acid) [56-58]. Compared with aliphatic-aromatic polyesters where the aliphatic dicarboxylic component is a shorter carbon chain length, such as BTA polyesters, these copolyesters do not show the sudden decrease of biodegradation properties above... 

The aliphatic components of suberin form polyester domains that are attached to the phenolics as indicated above (see Fig. 6.4.7). Activated cu-hydroxy acids and dicarboxylic acids are probably involved in the esterification as shown in cutin biosynthesis (232). It was proposed that the long-chain fatty alcohols found in suberin might be incorporated into the suberin polymer by peroxidase-catalyzed polymerization of phenylpropanoic acid esters of these alcohols (232), such as the ferulic acid esters of C18-C28 alcohols frequently found in suberin-as-sociated waxes (Table 6.4.2). 

The semi-crystalline character of polybutylene terephthalate and polyethylene terephthalate is the reason for their good resistance to chemicals. Organic solvents, such as aliphatic hydrocarbons, fuels, alcohols, ethers, long-chain esters, fats, oils, perchlorinated hydrocarbons, and the fiuorinated hydrocarbons used in aerosol technology do not attack thermoplastic polyesters at room temperature. These plastics are also resistant to weak acids, weak bases, water, and to aqueous solutions of neutral and acid salts at room temperature. However, they are non-resistant to strong acids, oxidizing acids, strong bases, ketones, and phenols. 

Polyester urethanes are synthesized from aliphatic polyesters. In order to be biodegradable, aliphatic polyesters have to he formed by macrodiols of succinic acid, adipic acid, sebacic acid and ethylene glycol, diethylene glycol, butanediol and/or hexanediol [953]. It is difficult to cleave phthalic acid polyesters, dodecanoic acid with short-chain diols, and polyesters of short-chain acids with long-chain diols, such dodecanediol. Table 5.137 [953]. 

Hult et al. [36] have described semi-crystalline hyperbranched aliphatic polyesters where the crystallinity was induced by attachment of long alkyl chains as end groups. The crystallization was affected by several factors such as length of the end groups and the molecular weight of the hyperbranched polyester. The crystallization was proposed as being either intra- or intermolecular depending on the size of the hyperbranched polyester onto which the alkyl chains were attached. 

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