Polyesters synthesis with immobilized lipase

However, Sails et al. [15] reported that solvent-free synthesis of oleic acid short-chain alcohols reached 100% of triolein conversion after only 6h at 40 °C by immobilized lipase of Pseudomonas cepacia. Furthermore, Kim [16] reported that the high conversion of 98.5% was possible at 45 °C of reaction temperature with 4 1 of methanol to oil molar ratio and 1% (v/v) methyl glucoside oleic polyester as an emulsifier using Novozym 435 in the presence of cosolvent. However, several researchers have reported that the conversion of... 

Polyacrylic resins were employed to study how immobilization resin particle size influences Candida antarctica Lipase B (CALB) loading, fraction of active sites, and catalytic properties for polyester synthesis. CALB adsorbed more rapidly on smaller beads. Saturation occurred in less than 30 seconds and 48 h for beads with diameters 35 and 560-710 pm, respectively. Infrared microspectroscopy showed that CALB forms protein loading fronts for resins with particle sizes 560-710 and 120 pm while CALB appears evenly distributed throughout 35 pm resins. The fraction of active CALB molecules adsorbed onto resins not influenced by particle size was less than 50 %. At about 5% w/w CALB loading, decrease in the immobilization support diameter from 560-710 to 120,75 and 35 pm increased conversion of s-CL to polyester (20 to 36, 42 and 61%, respectively, at 80 min). Similar trends were observed for condensation polymerizations of 1,8-octanediol and adipic acid. 

Synthesis of linear silicone aliphatic polyesters by the condensation polymerization of l,3-bis(3-carboxypropyl)tetra-methyldisiloxane with alkanediols (1,4-butanediol, 1,6-hex-anediol and 1,8-octanediol) using an immobilized lipase B from Candida antarctica (Novozym-435) as a catalyst, as shown in Scheme 2.2, has been reported [21]. These reactions were performed in the bulk (without the use of solvent) in the temperature range 50-90°C under reduced pressure (50-300 mmHg, vacuum gauge). 

Porcine Pancreas Lipase (PPL), a common lipase with low cost, could be immobilized on silica particles with good stability and recyclablity. Then the immoblized lipase (IPPL) was employed as the catalyst for polymer synthesis, such as polyesters, polycarbonates, polyphosphates, and their copolymers. Here we present a mini-review of some works in our lab within this area. 

Enzymatic polymerization has emerged in the last few decades as a field of considerable interest and commercial promises. It proceeds with high regio-, enantio-, and chemos-electivity under relatively mild conditions. So far, enzymes have been used to synthesize polyesters, polysaccharides, polycarbonates, polyphenols, polyanilines, vinyl polymers, and poly(amino acid)s. Namely, the lipase B of Candida antarctica (Cal-B, a serine hydrolase) immobilized on polyacrylic resin (Novozyme 435) has proven to be a very versatile catalyst in terms of reaction conditions and acceptance of various substrates. For example, this enzyme has been successfully used to synthesize polyesters. ° However, little has been reported so far on the synthesis of polyamides catalyzed by enzymes. " ... 

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