Polylactide aliphatic polyester

Tian D, Dubois P, Jerome R, Teyssie P (1994) Macromolecular engineering of polylactones and polylactides. 18. Synthesis of star-branched aliphatic polyesters bearing various functional end-groups. Macromolecules 27 4134 144... 

Abstract. This paper reviews the degradation behavior of aliphatic polyesters of current interest, including polylactide, polycaprolactone, poly(3-hydroxybutyrate) and their copolymers. Special focus is given to degradation products formed in different abiotic and biotic environments. The influence of processing and processing additives on the properties and degradation behavior is also briefly discussed. 

BMM623>, /3-valerolactone <2002JA15239>, and a-methyl-/3-pentylpropiolactone <2004T7177>. The polyester formed from the latter monomer was used in the formulation of immiscible blends or block copolymers with the biodegradable aliphatic polyester polylactide <2004T7177>. 

It is an aliphatic polyester derived from renewable resources, such as com starch, tapioca roots, chips or starch, or sugarcane. Polylactic acid or polylactide (PLA) can withstand temperatures up to 110 °C [69]. PLA is soluble in chlorinated solvents, hot benzene, tetrahydrofuran, and dioxane [70]. It can be processed like other thermoplastics into fiber (for example, using conventional melt spinning processes) and film. Due to the chiral nature of lactic acid, several distinct forms of polylactide exist ... 

Polylactide or Polylactic Acid (PLA) is a synthetic, aliphatic polyester from lactic acid (Figures 12.20 and 12.21). 

Dong, T., Dubois, P., Jdrdme, R., and Teyssie, P., 1994, Macromolecular Engineering of Polylactones and Polylactides. 18. Synthesis of Star-Branched Aliphatic Polyesters Bearing Various Functional End Groups. Macromolecules, 27 4134... 

Belonging to the family of aliphatic polyesters, poly(lactic acid) or polylactide (PLA) is composed of lactic acid repetitive units, which is the simplest ot-hydro)y acid with an asymmetric carbon atom. Interestingly, the L-lactic acid monomer, and more recently the D-lactic acid monomer, can be straightforwardly obtained by bacterial fermentation from renewable resources (namely starch), making both monomers and therefore the resulting polymers environmentally friendly. Polycondensation of lactic acid and ring-opening polymerization (ROP) of lactide (LA), i.e. cyclic diesters of lactic acid, are currently used to prepare PLA polymers (Scheme 4.1). 

Duro Bag Manufacturing Company EcoPLA bags consisted of three-layer blown film, with an interior layer of polylactide sandwiched between layers of a proprietary biodegradable aliphatic polyester. The bags were intended to replace paper bags for collection of compostables. ... 

Aliphatic polyesters are biocompatible and biodegradable polymers that are widely used in biomedical applications. Within these, polylactides and poly(s-caprolactone) are two of the most studied ones (Fig. 2). These polyesters can be synthesized via ring-opening polymerization of the corresponding cyclic esters (s-caprolactone and lactide) and via polycondensation of lactic acid. In material science, both pure aliphatic polyesters and natural polysaccharides have limitations in some specific applications. These limitations can be overcome by the introduction of hydrophilic groups (carbohydrate compounds) into the aliphatic polyesters and modifications of natural polysaccharides with hydrophobic polyesters. 

Bioresorbable linear aliphatic polyesters (e.g., polyglycolide, polylactide, polycaprolactone, polyhydroxybutyrate) and their copolymers within the aliphatic polyester family like poly(glycolide-L-lactide) copolymer and poly(glycolide-E-caprolactone) copolymer. 

It is well known that lipase can hydrolyze various kinds of aliphatic polyesters with low (below about 120°C). In general, the substrate specificity of lipases is very wide for aliphatic polyesters. Thus, lipases could hydrolyze polylactide with low (below about 120°C) such as... 

Polylactic acid or polylactide (PLA) is a thermoplastic aliphatic polyester that can be derived from renewable resources, such as corn starch or sugarcanes. Although PLA has been known for more than a century, it has become of great commercial interest in recent years because of its renewability and degradability to natural metabolites. In addition, the properties of PLA can be varied over a wide range which makes it suitable to be used as a substitute to many petroleum based commodity plastics, such as polyolefins,... 

Several researchers have focused their attention on the preparation of polylactide (PLA) nanocomposites. PLA is one type of hydrophobic aliphatic polyester, and as such, it is not water soluble. Therefore, solvent casting processes are carried out in nonpolar solvents such as chloroform or dichloromethane. In order to achieve intercalated stiuctures, the use of modified clays is mandatory (McLauchlin and Thomas 2009 Jaffar A 1-Mu I la 2011 Rhim et al. 2009 Chang and An 2002 Krikorian and Pochan 2003). Best results, i.e., partial or complete exfoliation, are... 

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