Succinate Based Polyesters

Another class of soft aliphatic polyesters are based on repeating succinate units such as PBSU, poly(butylene succinate adipate) (PBSA), and poly(ethylene succinate) (PES). Each of these succinate-based aliphatic polyesters are manufactured by Showa High Polymer, Ltd. and are sold imder the trade name Bionolle . Glass transition temperatures (Tg) and melting points (T ) of tree types are shown in Table 4.6. 

Applications for BionoUe include films, sheets, filaments, foam-molded products and foam-expanded products. Bionolle is biodegradable in compost, in moist soil, in water with activated sludge, and in sea water. PBSA degrades rapidly in a compost environment, similar to cellulose. PBSU degrades less rapidly, similar to a newspaper. 

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The Chemistry of Bio-based Polymers 4.1.12 Succinate Based Polyesters... 

The reaction of excess amounts of methyl acrylate and the self-metathesis products of monounsaturated fatty acids like methyl ester of oleic acid with ethylene, produces valuable monomers for polycondensation polymers, as well as precursors for detergents in the presence of a suitable metathesis catalyst. In oleochemistry, azaleic and pelargonic acid were obtained industrially by ozonolysis of oleic acid. Non-linear fatty acid derivatives with two double bonds, (ricinoleic acid maleate) and one double bond (ricinoleic acid succinate) were produced from ricinoleic acid by esterification with maleic and succinic anhydride, respectively. Hydrogenation of this ricinoleic acid succinate yielded 12-hydroxystearic acid succinate which is a monomer for vegetable oil-based polyester. 

Another commercialised type of biodegradable aliphatic polyester is succinate-based. Showa Highpolymer in Japan produces a family of aliphatic polyesters known as Bionolle . Bionolle is produced from glycols and aliphatic dicarboxylic acids such as succinic acid or modified acids. The structures of two different types of succinate aliphatic polyesters, polybutylene succinate (PBSU) and polyethylene succinate (PESU) are shown in Figure 6.6. 

The commercial polyester elastomers are mostly based on poly(tetrameth-ylene oxide) (PTMO) as flexible segment and poly(butylene terephthalate) (PBT) as rigid segment. Yet, many chemical modifications of some particular segments and also segments of totally different chemical structure have been examined and applied. Thus, in addition to PTMO [1,2,11-16], poly(ethylene oxide) (PEO) [17-22], poly(aliphatic oxide) (C2-C4) copolymers [23-30], poly (butylene succinate), and other aliphatic polyesters [31-35], polycaprolac-tone (PCL), polypivalolactone (PVL) [36,37], aliphatic polycarbonates (PC) [38-41], dimerized fatty acid (DFA)-based polyesters [42-50], polyamide 66 and derivatives [47-57], polyolefins [58-60], rubbers [61-63], and polydimethyl-siloxane [64,65] are used as flexible segments of polyester elastomers. 

Maleate/vinyl ether formulations based on a model unsaturated polyester prepared from maleic anhydride and 1,5-pentane diol and triethylene glycol divinyl ether were studied. At molecular weights of less than about 10,000 the cured films were extremely brittle. When the equivalent weight of the unsaturated polyester was increased by replacing some of the maleic anhydride with succinic anhydride, measurable values for film elongation could be obtained but the cure speed was definitely slower. When either diethyl maleate or isobutyl vinyl ether were added as monofunctional diluents the cure dose needed to obtain 200 MEKDR was increased and the flexibility measured by pencil hardness increased as the amount of diluent was increased. A urethane vinyl ether was synthesized and used to replace DVE-3 and films with increased elongation were obtained at equivalent at dosages as low as 1 J/cm2. 

We discovered another synthetic technique that involves the conversion by direct fluorination of hydrocarbon polyesters to perfluoropolyesters followed by treatment with sulfur tetrafluoride to produce new perfluoropolyethers.42 The first paper in this area ofreasearch reported that conversion of poly(2,2-dimethyl-1,3-propylene succinate) and poly( 1,4-butylene adipate) by using the direct fluorination to produce novel branched and linear perfluoropolyethers, respectively. The structures are shown in Figure 14.6. The second paper concerns the application of the direct fluorination technology base directed toward oligomers, diacids, diesters, and surfactants.43... 

Uses. About 60% of the MA produced is used to make unsaturated polyester and aikyd resins, which are formed by reaction of MA with glycols. Polyester resins are used in the fabrication of glass fiber reinforced parts. Applications include boat hulls, automobile body parts, patio furniture, shower stalls, and pipe. Aikyd resins are mostly used in coatings (paint, varnish, lacquers, and enamels). MA also is widely used as a chemical intermediate in the manufacture of plasticizers and dibasic acids (fumaric, maleic, and succinic). About 15% of MA production goes into the manufacture of viscosity index improvers and dispersants used as additives in lube oils. Several agricultural chemicals are based on maleic anhydride, the best known being Malathion. 

Several synthetic procedures have been developed for the production of biodegradable polyester-based materials from 1,3-propanediol and succinic acid obtainable from renewable resources. 

Nowadays, various aliphatic copolyesters based on succinate, adipate, ethylene glycol and 1,4-butanediol are being produced. Aliphatic polyesters based on natural feedstock such lactic acid are also being produced on a commercial scale by companies such as NatureWorks TLC. 

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. 

South Korean company SK Chemicals produces SKYGREEN polybutylene succinate (PBS) thermoplastics based on aliphatic polyester and aliphatic/aromatic co-polyesters that were developed from SK Chemicals polyethylene terephthalate (PET) technology. SKYGREEN BDP products offer LDPE-like properties. They are used in films, disposable cutlery, food trays, hairbrush handles and paper coatings. Aliphatic versions biodegrade more rapidly and offer better processing and tensile properties than the aromatic-aliphatic grades, which cost less. 

Many of these new plastics are in the polyester family. One that is getting attention is PEF, polyethylene furanoate. Avantium opened a PEE pilot plant in the Netherlands in 2011. PEF reportedly is similar to PET in performance, but is 100% biobased [10]. Polybutylene terephthalate (PBT) is available as a partially biobased plastic, from biobased 1,4-butanediol and petro-based terephthalic acid. Polybutylene succinate (PBS) is similarly made from biobased succinic acid and petro-based terephthalic acid. Poly(trimethylene terephthalate) (PTT) can be made from biobased 1,3-propanediol with, again, petro-based terephthalic acid. 

Showa Highpolymer (Japan) developed a wide range of polybutylene succinate (PBS) by polycondensation of 1,4-butanediol and succinic acid. Polybutylene succinate-co-adipate (PBSA), shown in Figure 9.4, is obtained by the addition of adipic acid. These copolymers are commercialized under the brand name Bionolle (Showa Denko K.K.). Industrial production of these polyesters from bio-based succinic acid was launched in 2012 by Showa Denko. Mitsubishi Chemical (Japan) produces and also commercializes partially bio-based PBS. 

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