A literature review is presented regarding the synthesis, and physicochemical, chemical, and mechanical properties of poly(lactic acid)(PLA). Poly(lactic acid) exists as a polymeric helix, with an orthorhombic unit cell. The tensile properties of PLA can vary widely, depending on whether or not it is annealed or oriented or what its degree of crystallinity is. Also discussed are the effects of processing on PLA. Crystallization and crystallization kinetics of PLA are also investigated. Solution and melt rheology of PLA is also discussed. Four different power-law equations and 14 different Mark–Houwink equations are presented for PLA. Nuclear magnetic resonance, UV–VIS, and FTIR spectroscopy of PLA are briefly discussed. Finally, research conducted on starch–PLA composites is introduced.

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A Literature Review of Poly(Lactic Acid)

23 Stereocontrol of Lactide ROP 6164 231 Isotactic Polylactides 6164 232 Syndiotactic Polylactides 6166 233 Heterotactic Polylactides 6166 3 Anionic Polymerization 6166 4 Nucleophilic Polymerization 6168 41 Mechanistic Considerations 6168 42 Catalysts 6169 421 Enzymes 6169 422 Organocatalysts 6169 43 Stereocontrol of Lactide ROP 6170 44 Depolymerization 6170 5 Cationic Polymerization 6170 6 Conclusion and Perspectives 6171 7 Acknowledgments 6173 8 References and Notes 6173

Controlled ring-opening polymerization of lactide and glycolide.

Poly(lactic acid) modifications

Recent Developments in Ring Opening Polymerization of Lactones for Biomedical Applications

Properties of lactic acid based polymers and their correlation with composition

Effect of carbon black (CB) on the morphology of filled polyethylene (PE)/polystyrene (PS) blends has been investigated by image analysis of optical micrographs (2-D analysis) and by the selective extraction of one phase of the binary blends (3-D analysis). The macroscopic electrical resistivity of the filled polyblends strongly depends on the selective localization of CB in one phase or at the interface and above all on the double percolation, i.e. percolation of the polymer phases and percolation of the CB particles. The selective localization of CB in the PE phase has remarkable effects on the polyblend phase morphology. The phase cocontinuity is indeed extended over a much larger composition range, and the phase morphology is stabilized toward post-thermal treatment at 200 °C. In the case of double percolation and selective localization of CB at the polyblend interface, electrical conductivity is observed at a CB content as low as 0.4 wt %.

Design of electrical conductive composites : key role of the morphology on the electrical properties of carbon black filled polymer blends

The ring-opening polymerization of lactides initiated by aluminium isopropoxide in toluene at 70°C proceeds through a «coordination-insertion» mechanism and selective rupture of the acyl oxygen bond of the monomer. A kinetic study has shown that the polymerization is first order in both the monomer and initiatior. The polymerization is typically «living» until a molecular weight of ca. 90000 is reached

Macromolecular engineering of polylactones and polylactides. 4. Mechanism and kinetics of lactide homopolymerization by aluminum isopropoxide

It is shown how efficiently the percolation threshold of carbon black in polyethylene/polystyrene heterogeneous blends can be decreased by selective localization of CB particle at the interphase rather than in one phase of the blend

Selective localization of carbon black in immiscible polymer blends: A useful tool to design electrical conductive composites

Several strategies are reported that allow carbon black (CB) particles to be selectively localized at the interface of polyethylene/polystyrene (PE/PS) blends used as models of two-phase polyblends. A first general approach relies upon a kinetic control, i.e., the choice of such processing conditions that the CB particles are “immobilized” at the polyblend interface at least for a workable period of time. The dry premixing of the two powdery polymers and CB particles followed by compression molding is the first valuable kinetic control. A second one can be implemented during the melt blending of the immiscible polymers, which makes this strategy more attractive. Actually, CB is first dispersed in the melted polymer with which it less strongly interacts. Upon the addition and melting of the second polymer, CB particles are thermodynamically driven to this second polymer phase. The conducting particles are observed to accumulate at the polyblend interface at a rate and for a period of time that depend on th...

Kinetic and thermodynamic control of the selective localization of carbon black at the interface of immiscible polymer blends

Polymerisation de l'acrylate de butyle dans le THF ou le melange THF/toluene, a −78°C, avec un amorceur RLi prepare par reaction du sec-BuLi avec un exces d'α-methylstyrene

R. Jerome

Papers

Design of electrical conductive composites : key role of the morphology on the electrical properties of carbon black filled polymer blends

Macromolecular engineering of polylactones and polylactides. 4. Mechanism and kinetics of lactide homopolymerization by aluminum isopropoxide

Selective localization of carbon black in immiscible polymer blends: A useful tool to design electrical conductive composites

Kinetic and thermodynamic control of the selective localization of carbon black at the interface of immiscible polymer blends

New initiator system for the "living" anionic polymerization of tert-alkyl acrylates