Molecular, Structural, and Material Design of Bio-Based Polymers

Abstract

Bio-based polymers are made from bio-originated feedstocks. Among those developed thus far, polylactides (PLA) stand at the forefront of practical use and are now manufactured on a commercial scale. However, the application of PLAs has been rather limited because of their higher cost, inferior thermal and mechanical properties, and worse processability as compared to the conventional oil-based polymers. Much effort has therefore been made to address it. Our major approach is to develop a direct polycondensation method to synthesize PLA and to use stereoblock-type PLA (sb-PLA) consisting of enantiomeric poly(L-lactide) (PLLA) and poly(D-lactide) (PDLA) because it can easily form stereocomplex (sc) showing a high melting temperature. Other specialty bio-based polymers are also synthesized for application to high-value fields. Particularly, with amphiphilic copolymers consisting of PLA and poly(oxyethylene) (PEG), new morphology change and sol-gel process have been disclosed. New bio-based polymers consisting of bio-derived monomeric units have also been synthesized to demonstrate their special functions. In addition, molecular and material design has been done with other biobased polymers such as poly(butylene succinate) (PBS) and poly(3-hydroxyalkanoate)s (PHA).

Development of crosslinkable poly(lactic acid-co-glycidyl methacrylate) copolymers and their curing behaviors

“…To overcome these drawbacks, many approaches have been performed, such as stereo-complexation, copolymerization, molecular design and blending with other polymers. [1][2][3][4][5][6][7][8][9][10][11][12][13][14] Copolymerization of lactide with specific functional comonomers is of interest for introducing functionality into PLA chains. Louis et al 14 reported the synthesis of a copolymer of lactide and glycidol by ring-opening polymerization.…”

Chapter 1. PLA Synthesis. From the Monomer to the Polymer

“…117 Two synthetic approaches are available for the copolymerization: (1) ring-opening copolymerization of L-lactide with other monomers such as e-caprolactone, glycolide and depsipeptides; and (2) use of new cyclic monomers consisting of lactate and other monomer units. In the former approach, random copolymers are usually prepared and the unit compositions of the comonomers are limited to 10 mol% to retain the polymer crystallinity.…”

Synthesis and properties of stereo di- and tri-block polylactides of different block compositions by terminal Diels-Alder coupling of poly-L-lactide and poly-D-lactide prepolymers

“…Until now, several aliphatic polyesters, such as poly(lactide)s (PLA), poly(butylene succinate) (PBS), and poly(3-hydroxyalkanoate)s (PHA), have been accepted by industries as the first manufacturing products. 1 Bio-originated polyamides, polycarbonates, and acrylic polymers are now under development as next generation polymers. Among these biobased polymers, only PLAs are now manufactured on a large scale and used as plastic materials for general purposes.…”