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

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.

2018 ◽  
Vol 6 (2) ◽  
pp. 626
Author(s):  
Irwan Noezar ◽  
V.S. Praptowidodo ◽  
R. Nugraheni ◽  
M.H. Nasution

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


2013 ◽  
Vol 641-642 ◽  
pp. 201-205
Author(s):  
Hong Su ◽  
Li Mei Guo ◽  
Lian Yong Wang

polycaprolactone diols (MW=540, 1000, 2000) and citric acid were used as monomers, polycaprolactone-citric acid preformed polymer was preparated firstly by the heating polycondensation, then the preformed polymer was heated and cross-linked to obtain biodegradable elastomeric material. The molecular structure and Molecular weight was proved respectively by 1-HNMR and Gel Permeation Chromatography (GPC). The shape and glass transition temperature (Tg) of polycaprolactone-citric acid polymer was certified by differential scanning calorimetry(DSC). The hydrophilicity of the polymer was evaluated by its contact angle. The polymer’s mechanical property and degradation speed was also investigated.


e-Polymers ◽  
2020 ◽  
Vol 20 (1) ◽  
pp. 162-170 ◽  
Author(s):  
Kaiji Yang ◽  
Jinghuan Chen ◽  
Qingjin Fu ◽  
Xuji Dun ◽  
Chunli Yao

AbstractA novel amphoteric polyacrylamide (PDAA) was prepared by inverse emulsion polymerization. The influence of its cationic degree and molecular weight on retention property was discussed. Then, the chemical structure and micromorphology of the obtained PDAA were characterized by Fourier infrared spectrum (FTIR), NMR hydrogen spectrum (1H NMR), gel permeation chromatography (GPC), and scanning electron microscope (SEM). Finally, the synergistic retention effects of polydimethyldiallylammonium chloride (PDADMAC), cationic starch (CS), cationic guar gum (CHPG), cationic chitosan (CTS), and polyamine (PA) on the novel PDAA were investigated. The results showed that the optimum cationic degree and molecular weight of PDAA were 25% and 4 million, respectively. The chemical structure of PDAA was confirmed by FTIR, 1H NMR, and GPC. SEM showed that the particle size of PDAA was between 150 and 600 nm, and the particles were very stable because no broken particles were found. In addition, most of the five cationic polymers have good synergistic retention effect on PDAA, and the order of synergistic effect was PDAA/PDADMAC > PDAA/CTS > PDAA/CS > PDAA/CHPG > PDAA/PA.


2013 ◽  
Vol 747 ◽  
pp. 148-152
Author(s):  
Chaichana Piyamawadee ◽  
Duangdao Aht-Ong

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).


2008 ◽  
Vol 47-50 ◽  
pp. 1458-1461 ◽  
Author(s):  
Biao Fu ◽  
Lin Xiao ◽  
Long Jiang Yu ◽  
Guang Yang

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.


2014 ◽  
Vol 34 (7) ◽  
pp. 665-672 ◽  
Author(s):  
Yottha Srithep ◽  
Wuttipong Rungseesantivanon ◽  
Bongkot Hararak ◽  
Krisda Suchiva

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.


Polymers ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 1822
Author(s):  
Evangelia Balla ◽  
Vasileios Daniilidis ◽  
Georgia Karlioti ◽  
Theocharis Kalamas ◽  
Myrika Stefanidou ◽  
...  

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.


2012 ◽  
Vol 487 ◽  
pp. 48-52
Author(s):  
Sheng Hua Lv ◽  
Gong Rui ◽  
Di Li

The radical copolymerization of resorcinol (RSC) and 3,5-dihydroxyl benzoic (DHBA) was carried out in water by the initiator of horseradish (HRP)/H2O2. It was discussed that the effects of monomer composition on the properties of the copolymer. The best monomer mass ratio of RSC:DHBA was 60:40 and the shrink temperature can reached to 88.5oC. The tanning result indicated that the copolymer of RSC and DHPA has particularly excellent tanning properties and can be served as leather tannage substitute for chrome tanning materials. And also the mechanism of the HRP initiated copolymerization was proposed. The structure and molecular weight of the copolymer was characterized by Fourier Transform Infrared spectroscopy (FTIR), Nuclear Magnetic Resonance (NMR) and Gel Permeation Chromatography (GPC). The copolymer can be as tannage and retannage in making leather process. The results showed that it has excellent tanning properties and retanning effects.


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