The basic properties of poly(lactic acid) produced by the direct condensation polymerization of lactic acid

1995 ◽  
Vol 3 (4) ◽  
pp. 225-234 ◽  
Author(s):  
M. Ajioka ◽  
K. Enomoto ◽  
K. Suzuki ◽  
A. Yamaguchi
Keyword(s):  
Lactic Acid ◽  
Poly Lactic Acid ◽  
Condensation Polymerization ◽  
Basic Properties ◽  
Direct Condensation

Basic Properties of Polylactic Acid Produced by the Direct Condensation Polymerization of Lactic Acid

1995 ◽  
Vol 68 (8) ◽  
pp. 2125-2131 ◽  
Author(s):  
Masanobu Ajioka ◽  
Katashi Enomoto ◽  
Kazuhiko Suzuki ◽  
Akihiro Yamaguchi
Keyword(s):  
Lactic Acid ◽  
Polylactic Acid ◽  
Condensation Polymerization ◽  
Basic Properties ◽  
Direct Condensation

Direct condensation polymerization of lactic acid

1999 ◽  
Vol 144 (1) ◽  
pp. 277-287 ◽  
Author(s):  
Soo Hyun Kim ◽  
Young Ha Kim
Keyword(s):  
Lactic Acid ◽  
Condensation Polymerization ◽  
Direct Condensation

The Influence of Amount of Succinic Anhydride in Chain Extension Reaction on Increasing Molecular Weight of Poly(lactic acid)

2013 ◽  
Vol 747 ◽  
pp. 148-152
Author(s):  
Chaichana Piyamawadee ◽  
Duangdao Aht-Ong
Keyword(s):  
Molecular Weight ◽  
Lactic Acid ◽  
Succinic Anhydride ◽  
Gel Permeation Chromatography ◽  
Chain Extension ◽  
Proton Nuclear Magnetic Resonance ◽  
Poly Lactic Acid ◽  
Condensation Polymerization ◽  
Scanning Calorimetry ◽  
Molar Ratios

High molecular weight PLA was successfully synthesized by chain extension reaction of hydroxylated prepolymer using succinic anhydride as a chain extender. Hydroxylated prepolymer was prepared by direct condensation polymerization of L-lactic acid in the presence of 1,4-butanediol. Various molar ratios between hydroxylated prepolymer and succinic anhydride (i.e, 1:1, 1:2, 1:3) were investigated. The results showed that succinic anhydride can help increasing molecular weight of hydroxylated prepolymer approximately up to 47% as characterized by gel permeation chromatography (GPC) technique. Proton nuclear magnetic resonance (1H-NMR) was used to investigate structure of chain-extended PLA. Differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) were used to examine thermal properties while the crystallinity was investigated by X-ray diffraction (XRD).

scholarly journals Cyclic Oligolactic Acid in Direct Polycondensation PLLA and Its Extraction with Organic Solvent

2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
Keiichiro Nomura ◽  
Yuta Nakatsuchi ◽  
Ryugo Shinmura ◽  
Sommai Pivsa-Art ◽  
Weraporn Pivsa-Art ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Lactic Acid ◽  
Selective Extraction ◽  
Condensation Polymerization ◽  
Direct Polycondensation ◽  
H Nmr ◽  
Repeat Units ◽  
Molecular Inclusion ◽  
Cyclic Compounds ◽  
Direct Condensation

The contents of poly(L-lactic acid) (PLLA) prepared by direct condensation polymerization without using a catalyst were studied. 1H NMR and mass spectrometry analyses suggested that PLLA contained cyclic oligo(L-lactic acid) (c-OLLA) with 3–20 repeat units. Notably, only c-OLLA was extracted and isolated using hexane or cyclohexane at 4°C; thus the hydrophobicity, topology, and temperature dependence of the solubility of the obtained PLLA enabled the selective extraction of c-OLLA. The effect of cyclic compounds on direct polycondensation and the potential for c-OLLA to form molecular inclusion complexes were also discussed.

Synthesis and Properties of New Biodegradable Polyurethane Containing Natural Rubber and Poly(lactic Acid): Effect of NR and PLA Ratio

2012 ◽  
Vol 531-532 ◽  
pp. 317-320
Author(s):  
Chuanpit Khaokong ◽  
Jinwara Suwanmanee ◽  
Jean François Pilard ◽  
Pamela Pasetto ◽  
Varaporn Tanrattanakul
Keyword(s):  
Lactic Acid ◽  
Natural Rubber ◽  
Oxidative Degradation ◽  
Hydroxyl Group ◽  
Poly Lactic Acid ◽  
Dibutyltin Dilaurate ◽  
Condensation Polymerization ◽  
Biodegradable Polyurethane ◽  
Group Chemical ◽  
Butane Diol

Biodegradable polyurethane was synthesized using poly(DL-lactic acid) diol and hydroxytelechelic natural rubber as hydroxyl containing precursor, 1,4-butane diol as chain extender, isophorone diisocyanate and dibutyltin dilaurate as catalyst. Poly(DL-lactic acid) diol was prepared by condensation polymerization of DL-lactic acid using 1,4-butane diol as initiator and stannous octoate as catalyst. Hydroxyltelechelic natural rubber synthesized via oxidative degradation of natural rubber and then reduced carbonyl end group to hydroxyl group. Chemical structure of products was characterized by 1H-NMR. Molecular weight and polydispersity determined by SEC. Thermal properties was characterized by DSC and TGA. Segmented polyurethane show two Tgs and two degradation steps corresponding to natural rubber and poly(DL-lactic acid) segment. Polyurethane containing poly(lactic acid) more than 40%mol are become brittle. This result caused by brittle characteristic of PLA. Moreover, mechanical properties increased as content of PLA increased.

Direct Condensation Polymerization of L-Lactic Acid Catalyzed by Distannoxane

1996 ◽  
Vol 25 (3) ◽  
pp. 225-226 ◽  
Author(s):  
Junzo Otera ◽  
Kazuko Kawada ◽  
Toru Yano
Keyword(s):  
Lactic Acid ◽  
Condensation Polymerization ◽  
Acid Catalyzed ◽  
Direct Condensation

scholarly journals Biodegradable polymer dari asam laktat

2018 ◽  
Vol 6 (2) ◽  
pp. 626
Author(s):  
Irwan Noezar ◽  
V.S. Praptowidodo ◽  
R. Nugraheni ◽  
M.H. Nasution
Keyword(s):  
Molecular Weight ◽  
Lactic Acid ◽  
Biodegradable Polymer ◽  
Gel Permeation Chromatography ◽  
Polymerization Reaction ◽  
Poly Lactic Acid ◽  
Condensation Polymerization ◽  
Purity Analysis ◽  
Gel Permeation ◽  
Degradation Time

The objective of this research is to learn and to make the biodegradable polymer, Poly(lactic acid), from lactic acid by condensation polymerization without catalyst. Poly(lactic acid) that will be produced in this research should have the molecular weight between 3000-5000 grams/mole. The scopes of this research are the_purification of lactic acid, purity analysis, polymerization reaction, and polymer's characteristic analysis. The method of lactic acid purification is distillation in nitrogen atmosphere. Polymerization reaction which is used in this research is the condensation polymerization without catalyst. The polymer's characteristics that will be analyzed are molecular weight and  degradation time Molecular weight is analyzed by viscosimetry method and Gel Permeation Chromatography. Degradation time is analyzed by landfill method Based on this research, purification of D,L-lactic acid (91%-weight) reaches 98%-weight and for L-lactic acid (93%-weight) reaches 96%-berat. Molecular weight of D,L-lactic acid between 450-3600 grams/mole and L-lactic acid between 4200-8500 grams/mole.  The degradation time of polymer is 5 weeks.Keywords: Poly(lactic acid), polymer,  biodegradable AbstrakPenelitian ini bertujuan untuk mempelajari dan mensintesis biodegradable polymer, Poly(lactic acid) dari asam laktat melalui reaksi polimerisasi kondensasi tanpa katalis. Poly(lactic acid) yang dihasilkan dalam penelitian ini diharapkan memiliki berat molekul antara 3000-5000 gram/mol. Ruang lingkup penelitian meliputi pemurnian asam laktat, analisa kemurnian asam laktat, reaksi polimerisasi kondensasi dan karakterisasi polimer. Pemurnian asam laktat dilakukan melalui distilasi pada atmosfer nitrogen dan tekanan 1 atmosfer. Reaksi polimerisasi dilakukan melalui polimerisasi kondensasi tanpa katalis dengan variasi waktu reaksi pengadukan mekanik dan laju pemanasan. Karakteristik polimer yang dianalisis adalah berat molekul dan waktu degradasi. Berat molekul dianalisis dengan metode GPC (Gel Permeation Chromatography) dan viskosimetri. Degradasi polimer dilakukan secara landfill. Berdasarkan hasil percobaan, pemurnian asam laktat untuk monomer D,L-Lacticacid (91%-berat) mencapai 98%-berat sedangkan untuk monomer L-Lactic acid (93%-berat) mencapai 96%-berat. Berat molekul yang dihasilkan untuk monomer D,L-Lactic acid adalah 450 - 3600 gram/mol sedangkan untuk monomer L-Lactic acid adalah 4200- 8500 gram/mol. Waktu degradasi polimer secara landfill adalah 5 minggu.Kata kunci : Poly(lactic acid), polimer, biodegradable

Electrical Properties of Heat-Treated Poly-Lactic Acid

2011 ◽  
Vol 131 (5) ◽  
pp. 395-400 ◽  
Author(s):  
Toru Oi ◽  
Katsuyoshi Shinyama ◽  
Shigetaka Fujita
Keyword(s):  
Lactic Acid ◽  
Electrical Properties ◽  
Poly Lactic Acid ◽  
Heat Treated
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