Synthesis of High Molecular Weight Poly(l-lactic acid) via Melt/Solid State Polycondensation. II. Effect of Precrystallization on Solid State Polycondensation

2012 ◽  
Vol 51 (14) ◽  
pp. 5190-5196 ◽  
Author(s):  
Bo Peng ◽  
Hongbing Hou ◽  
Fangchao Song ◽  
Linbo Wu
Keyword(s):  
Molecular Weight ◽  
Lactic Acid ◽  
Solid State ◽  
High Molecular Weight ◽  
High Molecular Weight Poly

Preparation and characterization of high molecular weight poly(trimethylene terephthalate) by solid-state polymerization

e-Polymers ◽  
2011 ◽  
Vol 11 (1) ◽  
Author(s):  
Kim Seok Hoon ◽  
Kim Joon Ho
Keyword(s):  
Molecular Weight ◽  
Reaction Time ◽  
Solid State ◽  
High Molecular Weight ◽  
Melting Temperature ◽  
Average Molecular Weight ◽  
Pellet Size ◽  
Solid State Polymerization ◽  
Trimethylene Terephthalate ◽  
High Molecular Weight Poly

AbstractSolid-state polymerization has been widely used to prepare high molecular weight poly(ethylene terephthalate). Solid-state polymerization is generally carried out by heating solid, melt-phase-polymerized polymer below its melting temperature but above its glass transition temperature. Solid-state polymerization of poly(trimethylene terephthalate)(PTT) is not an independent process but rather an additional process with respect to melt polymerization that is used when PTT of a higher molecular weight is required. Two kinds of commercial PTT chips were polymerized in the solid state to prepare high molecular weight PTT, which were characterized by end group contents, molecular weight, thermal analysis and X-ray diffraction. In the solid-state polymerization of PTT, the overall reaction rate was governed by the reaction temperature, reaction time and pellet size. The content of carboxyl end groups was decreased during the solid-state polymerization with increasing reaction time and temperature. The melting temperature and crystallinity of solid-state-polymerized PTT were higher at longer times and higher temperatures of polymerization. The activation energy for the solid-state polymerization of PTT was in the range of 24~25 kcal/mol for each chip. Through the solid-state polymerization of commercial PTT chips, we could get high molecular weight polymers up to an intrinsic viscosity value of 1.63 dl/g, which is equivalent to about a 117,000 weight-average molecular weight.

A solid-state synthesis, mechanism, and characterization of high molecular weight poly (3-aminobenzenesulfonic acid) with FeCl3.6H2O as a binary oxidant and dopant

2019 ◽  
Vol 26 (1) ◽  
Author(s):  
Ali Reza Modarresi-Alam ◽  
Vahid Zeraatkar ◽  
Fateme Alsadat Tabatabaei ◽  
Mojdeh Bazrafkan ◽  
Amirhosein Salmani Dastgerdi ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Solid State ◽  
High Molecular Weight ◽  
Solid State Synthesis ◽  
Synthesis Mechanism ◽  
High Molecular Weight Poly

Organometal-catalyzed synthesis of high molecular weight poly-(l-lactic acid) with a covalently attached imidazolium salt: performance-enhanced reduced graphene oxide–PLLA biomaterials

2019 ◽  
Vol 43 (41) ◽  
pp. 16367-16373 ◽  
Author(s):  
Yuri Clemente Andrade Sokolovicz ◽  
Clarissa Martins Leal Schrekker ◽  
Frédéric Hild ◽  
Leonardo de Oliveira Bodo ◽  
Júlia Lacerda Couto ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Graphene Oxide ◽  
Lactic Acid ◽  
High Molecular Weight ◽  
Reduced Graphene Oxide ◽  
Imidazolium Salt ◽  
Reduced Graphene ◽  
High Molecular Weight Poly

Herein, we report on the synthesis of imidazolium salt end-functionalized PLLA (PLLA-IS) and its application in the preparation of reduced graphene oxide–PLLA composites.

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