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

scholarly journals Biodegradation Behavior of Poly(Butylene Adipate-Co-Terephthalate) (PBAT), Poly(Lactic Acid) (PLA), and Their Blend in Freshwater with Sediment

Molecules ◽  
2020 ◽  
Vol 25 (17) ◽  
pp. 3946
Author(s):  
Ye Fu ◽  
Gang Wu ◽  
Xinchao Bian ◽  
Jianbing Zeng ◽  
Yunxuan Weng
Keyword(s):  
Molecular Structure ◽  
Molecular Weight ◽  
Lactic Acid ◽  
Chemical Structure ◽  
Gel Permeation Chromatography ◽  
Poly Lactic Acid ◽  
Relative Peak Area ◽  
Butylene Terephthalate ◽  
Aggregation Structure ◽  
Gel Permeation

Poly(butylene adipate-co-terephthalate) (PBAT) and poly(lactic acid) (PLA) are well-known biodegadable polyesters due to their outstanding performance. The biodegradation behavior of PLA/PBAT blends in freshwater with sediment is investigated in this study by analyzing the appearance, chemical structure and aggregation structure of their degraded residues via SEM, TG, DSC, gel permeation chromatography (GPC) and XPS. The effect of aggregation structure, hydrophilia and biodegradation mechanisms of PBAT and PLA on the biodegradability of PLA/PBAT blends is illuminated in this work. After biodegradation, the butylene terephthalate unit in the molecular structure of the components and the molecular weight of PLA/PBAT blends decreased, while the content of C-O bond in the composites increased, indicating that the samples indeed degraded. After 24 months of degradation, the increase in the relative peak area proportion of C-O to C=O in PLA/PBAT-25, PLA/PBAT-50 and PLA/PBAT-75 was 62%, 46% and 68%, respectively. The biodegradation rates of PBAT and PLA in the PLA/PBAT blend were lower than those for the respective single polymers.

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).

Biodegradation Behavior of PLA/PBS Blends

2013 ◽  
Vol 821-822 ◽  
pp. 937-940 ◽  
Author(s):  
Shi Jie Zhang ◽  
Yi Wen Tang ◽  
Li Hua Cheng
Keyword(s):  
Molecular Weight ◽  
Weight Loss ◽  
Lactic Acid ◽  
Average Molecular Weight ◽  
Poly Lactic Acid ◽  
Degradation Behavior ◽  
Butylene Succinate ◽  
Exponential Decrease ◽  
Degradation Time

Poly (butylene succinate) (PBS) was mixed with Poly (lactic acid) (PLA) in the melt state. The PLA/PBS blends with different constitution were produced. The samples were buried in laterite. Samples were dug out of soil after the burial for 10, 20, 30, 40, 50 and 60 days, respectively. The weight loss and molecular weight of the sample were tested. The analysis showed that the nearly exponential decrease in average molecular weight as a function of degradation time. The PLA and PBS have the similar degradation behavior in the soil.

Kinetic parameters estimation of ring-opening poly(lactic acid) polymerization by modeling and simulation

2011 ◽  
Vol 31 (2-3) ◽  
Author(s):  
Rajeev Mehta ◽  
Vineet Kumar ◽  
Sidh Nath Upadhyay
Keyword(s):  
Molecular Weight ◽  
Lactic Acid ◽  
Rate Constants ◽  
Ring Opening ◽  
Numerical Technique ◽  
Kinetic Scheme ◽  
Degree Of Polymerization ◽  
Parameters Estimation ◽  
Polymerization Reaction ◽  
Poly Lactic Acid

Abstract The modeling of ring-opening polymerization of lactide to poly(lactic acid) (PLA) has been carried out. Carothers first synthesized PLA in 1932. Since then, hundreds of research papers and patents have appeared in the literature. However, there is a lack of data concerning the rate constants for initiation, propagation and termination steps of PLA polymerization, except some data about the apparent rate constant. This work investigates, theoretically, the individual rate constants using a simple numerical technique. The progress of lactide polymerization can be modeled by assuming a ring opening reaction mechanism comprising chain initiation, chain propagation, and chain termination. The simulator developed, based on the solutionof differential equations corresponding to the above-mentioned kinetic scheme, Generates a detailed molecular weight distribution that can be used to estimate average molecular weights (or average degree of polymerization) vs. polymerization time curves. These simulated curves, on matching with the reported experimental data (for different catalysts), yield the absolute values of rate constants. The values have been determined for zinc lactate. Rate constants could be determined by using the molecular weight and the polydispersity vs. polymerization data. This methodology offers greater opportunity for capturing high, non-equilibrium polymer yield through appropriately timed termination of the polymerization reaction.

Preparation of Lactic Acid Based Polyurethanes Modified by Castor Oil

2008 ◽  
Vol 47-50 ◽  
pp. 1458-1461 ◽  
Author(s):  
Biao Fu ◽  
Lin Xiao ◽  
Long Jiang Yu ◽  
Guang Yang
Keyword(s):  
Mechanical Properties ◽  
Molecular Weight ◽  
Lactic Acid ◽  
Castor Oil ◽  
Average Molecular Weight ◽  
Tensile Modulus ◽  
Gel Permeation Chromatography ◽  
Elongation At Break ◽  
Gel Permeation ◽  
Soft Tissue Engineering

A series of biodegradable lactic acid based Polyurethanes modified by castor oil (PLBA-PUs) have been successfully prepared by using a two steps method as follow: Firstly prepolymers with hydroxyl terminated are synthesized by copolymerization of L-lactic acid and 1, 4-butandiol (BD), and then react with castor oil (C.O.) and hexamethylene diisocynate (HDI). The effects of BD/LA monomer ration and C.O./prepolymers mole ratio on the molecular weight and mechanical properties of PLBA-PUs are investigated. The polymers obtained are characterized by gel permeation chromatography, fourier transform infrared spectroscopy, 13C NMR, differential scanning calorimeter (DSC) and tensile testing. Their average molecular weight is over 280,000. They display excellent mechanical properties, such as a tensile strength as high as 31MPa, a tensile modulus as low as 20 MPa, and an elongation at break of 176%. Due to the biocompatibility, these PUs could find applications in biomedical fields, such as soft-tissue engineering.

scholarly journals Biodegradable Star-shaped Poly(Lactic Acid): Synthesis, Characterization and Its Reaction Kinetics

2021 ◽  
Author(s):  
Jing He ◽  
Tao Yu ◽  
Weidong Yang ◽  
Yan Li
Keyword(s):  
Lactic Acid ◽  
Reaction Kinetics ◽  
Gel Permeation Chromatography ◽  
Acid Synthesis ◽  
Polymerization Kinetics ◽  
Polymerization Reaction ◽  
Molar Ratio ◽  
Poly Lactic Acid ◽  
H Nmr ◽  
Optimum Reaction

Abstract Biodegradable four-arm star-shaped poly(lactic acid) (4sPLA) was synthesized from L-Lactic acid ( L-LA) and pentaerythritol (PENTA), and the polymerization kinetics was studied. The effects of reaction time, reaction temperature and molar ratio on the polymerization of 4sPLA were discussed. The molecular structure of 4sPLA was characterized by Fourier transform infrared spectroscopy (FTIR) and 1H nuclear magnetic resonance spectra ( 1 H-NMR). The results showed that the optimum reaction conditions were as follows: the molar ratio of L-LA to PENTA was 12:1, and the polymerization reaction occurred at 160 ℃ for 5 h. Gel permeation chromatography (GPC) method was used to determine the polymerization kinetics of 4sPLA consistent with the first-order reaction kinetics.

Processing and characterization of poly(lactic acid) blended with polycarbonate and chain extender

2014 ◽  
Vol 34 (7) ◽  
pp. 665-672 ◽  
Author(s):  
Yottha Srithep ◽  
Wuttipong Rungseesantivanon ◽  
Bongkot Hararak ◽  
Krisda Suchiva
Keyword(s):  
Molecular Weight ◽  
Lactic Acid ◽  
Gel Permeation Chromatography ◽  
Chain Extender ◽  
Chain Extension ◽  
Morphological Properties ◽  
Poly Lactic Acid ◽  
Scanning Calorimetry ◽  
Commercial Applications ◽  
A Chain

Abstract Currently, use of poly(lactic acid) (PLA) is limited for commercial applications because it has a low heat resistance. In this research, an increase of over 40°C heat distortion temperature (HDT) of PLA alloy was obtained by blending PLA with polycarbonate (PC) and a chain extender (CE). Molecular weight, thermal, mechanical and morphological properties of PLA and PC blend with different CE contents were investigated. Gel permeation chromatography (GPC) results showed that some PLA-PC copolymers were produced and the compatibility of the PLA phase and in the PC phase was improved via the chain extension reaction. In addition, the reaction induced by CE also affected the crystallization behaviors of PLA, as observed from differential scanning calorimetry (DSC) results and the enthalpy of melting of PLA decreased with increasing CE content. The combined effects of the CE increasing molecular weight, improving compatibility and limiting the crystallization behavior of PLA/PC alloy greatly improved the HDT.

scholarly journals Poly(lactic Acid): A Versatile Biobased Polymer for the Future with Multifunctional Properties—From Monomer Synthesis, Polymerization Techniques and Molecular Weight Increase to PLA Applications

Polymers ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 1822
Author(s):  
Evangelia Balla ◽  
Vasileios Daniilidis ◽  
Georgia Karlioti ◽  
Theocharis Kalamas ◽  
Myrika Stefanidou ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Lactic Acid ◽  
Chain Extension ◽  
Poly Lactic Acid ◽  
Plastic Pollution ◽  
Practical Applications ◽  
Decomposition Reactions ◽  
Melt Polycondensation ◽  
Polymerization Conditions ◽  
Molecular Weight Increase

Environmental problems, such as global warming and plastic pollution have forced researchers to investigate alternatives for conventional plastics. Poly(lactic acid) (PLA), one of the well-known eco-friendly biodegradables and biobased polyesters, has been studied extensively and is considered to be a promising substitute to petroleum-based polymers. This review gives an inclusive overview of the current research of lactic acid and lactide dimer techniques along with the production of PLA from its monomers. Melt polycondensation as well as ring opening polymerization techniques are discussed, and the effect of various catalysts and polymerization conditions is thoroughly presented. Reaction mechanisms are also reviewed. However, due to the competitive decomposition reactions, in the most cases low or medium molecular weight (MW) of PLA, not exceeding 20,000–50,000 g/mol, are prepared. For this reason, additional procedures such as solid state polycondensation (SSP) and chain extension (CE) reaching MW ranging from 80,000 up to 250,000 g/mol are extensively investigated here. Lastly, numerous practical applications of PLA in various fields of industry, technical challenges and limitations of PLA use as well as its future perspectives are also reported in this review.

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