scholarly journals Preparation of poly(.ALPHA.-D,L-malic acid-co-glycolic acid) by ring-opening polymerization of a novel cyclic diester.

1989 ◽  
Vol 46 (4) ◽  
pp. 281-284 ◽  
Author(s):  
Yoshiharu KIMURA ◽  
Kenji SHIROTANI ◽  
Hideki YAMANE ◽  
Toshio KITAO
2019 ◽  
Vol 52 (20) ◽  
pp. 7564-7571 ◽  
Author(s):  
Yaru Wang ◽  
Zhaowei Jia ◽  
Jinxing Jiang ◽  
Xiaoyang Mao ◽  
Xiaobo Pan ◽  
...  

2011 ◽  
Vol 2 (10) ◽  
pp. 2204 ◽  
Author(s):  
Ryan J. Pounder ◽  
David J. Fox ◽  
Ian A. Barker ◽  
Michael J. Bennison ◽  
Andrew P. Dove

e-Polymers ◽  
2010 ◽  
Vol 10 (1) ◽  
Author(s):  
Guang Li ◽  
Na Zhao ◽  
Wei Bai ◽  
Dong Liang Chen ◽  
Cheng Dong Xiong

AbstractThe microwave-assisted synthesis of poly(glycolic acid-co-lactic acid) (PGLA) copolymers by ring-opening polymerization of glycolide (GA) and L-lactide (L-LA) was studied. The microwave irradiation time and feed ratios on the molecular weights, as well as the thermal properties of the copolymers were discussed. These copolymers were characterized by 1H-NMR, GPC and DSC. It was found that the largest molecular weight ([η]: 0.8745 dL/g) of PGLA5050 was obtained at the irradiation time of 5 min. The color of the copolymers changed from white to light brown, and the yield was higher with the extension of the irradiation time. The molar component ratio of GA in PGLA (FG) was higher than the initial GA feed ratio (nGA) in the raw materials. As the nGA content increased, the glass transition temperature (Tg) of the copolymers decreased and the melting temperature (Tm) of the copolymers increased.


METANA ◽  
2021 ◽  
Vol 17 (2) ◽  
pp. 88-96
Author(s):  
Sari Purnavita ◽  
Lucia Hermawati ◽  
Elisa Rinihapsari

Polimer Poli Asam Laktat Glikolat (PLGA) merupakan salah satu jenis polimer yang telah disetujui FDA dan EMA untuk penggunaan biomedik. Kelebihan PLGA yaitu biokompatibilitas, biodegradabilitas, fleksibilitas, dan efek samping yang minimal. PLGA telah dikembangkan untuk penggunaan medis namun pemenuhannya masih berupa impor. Oleh karena itu, pada penelitian ini monomer asam laktat dari limbah pati aren dan asam glikolat dengan rasio LA:GA = 75%:25%; 90%:10%; 95%:5%; direaksikan secara Ring Opening Polymerization (ROP) dengan bantuan katalis Sn(II) Oktoat membentuk PLGA. PLGA hasil kemudian ditambahkan PVA, dengan rasio PLGA:PVA 3:2; 3:3; 3:4; dan 3:5 dengan metode solution casting membentuk film. Penelitian dilakukan secara eksperimental dengan Rancangan Acak Lengkap (RAL) faktorial. Hasil penelitian menunjukkan adanya kombinasi rasio LA:GA dan rasio penambahan PVA mempengaruhi karakteristik film PLGA.  Hasil kekakuan dan Modulus Young film PLGA tertinggi pada kombinasi penambahan rasio LA:GA = 75%:25% dan penambahan rasio PLGA:PVA =3:4. Biodegrabilitas film PLGA terbaik pada kombinasi penambahan rasio LA:GA 90%:10% dan penambahan rasio PLGA:PVA 3:4. Film PLGA memiliki biokompatibilitas yang baik pada semua rasio LA:GA, dengan penambahan rasio PLGA:PVA lebih dari 3:2. Hasil film PLGA memiliki morfologi permukaan paling halus pada rasio penambahan PLGA : PVA 3:2, dan memiliki struktur semi kristalin.Lactic Glycolic Acid Polymer (PLGA) is a type of polymer that has been approved by the FDA and EMA for biomedical use. The advantages of PLGA are biocompatibility, biodegradability, flexibility, and minimal side effects. PLGA has been developed for medical use but fulfillment is still imported. Therefore, in this study, the lactic acid monomer from waste palm starch and glycolic acid with a ratio of LA: GA = 75%: 25%; 90%: 10%; 95%: 5%; reacted with Ring Opening Polymerization (ROP) with the help of a catalyst Sn (II) Octoate to form PLGA. The resulting PLGA was then added with PVA, with a ratio of PLGA: PVA 3: 2; 3: 3; 3: 4; and 3: 5 with the solution casting method forming the film. This research was conducted experimentally with a factorial completely randomized design (CRD). The results showed that the combination of LA: GA ratio and PVA addition ratio affected the PLGA film characteristics. The results of stiffness and Young's Modulus of PLGA film were highest in the combination of addition of the ratio of LA: GA = 75%: 25% and the addition of the ratio of PLGA: PVA = 3: 4. The best PLGA film biodegradability was combined with the addition of the ratio of LA: GA 90%: 10% and the addition of the PLGA: PVA ratio 3: 4. PLGA film has good biocompatibility in all LA: GA ratios, with the addition of a PLGA: PVA ratio of more than 3: 2. The results of the PLGA film had the smoothest surface morphology at the ratio of addition of PLGA: PVA 3: 2, and had a semi-crystalline structure.


2020 ◽  
Vol 11 (39) ◽  
pp. 6365-6373
Author(s):  
Kaoru Takojima ◽  
Hiroshi Makino ◽  
Tatsuya Saito ◽  
Takuya Yamamoto ◽  
Kenji Tajima ◽  
...  

Highly regioselective ring-opening polymerization of optically active methylglycolides was achived using P2-t-Bu/alcohol system to produce alternating copolymer of lactic acid and glycolic acid.


2009 ◽  
Vol 47 (5) ◽  
pp. 1440-1449 ◽  
Author(s):  
Estelle Gautier ◽  
Patrick Fuertes ◽  
Philippe Cassagnau ◽  
Jean-Pierre Pascault ◽  
Etienne Fleury

2016 ◽  
Vol 7 (28) ◽  
pp. 4603-4608 ◽  
Author(s):  
Ghislaine Barouti ◽  
Sophie M. Guillaume

Poly(benzyl β-malolactonate)-b-poly(3-hydroxybutyrate)-b-poly(benzyl β-malolactonate), PMLABe-b-PHB-b-PMLABe, and its analogous poly(β-malic acid), PMLA-b-PHB-b-PMLA, triblock copolymers are synthesized and fully characterized.


e-Polymers ◽  
2007 ◽  
Vol 7 (1) ◽  
Author(s):  
Souad Dali ◽  
Hervé Lefebvre ◽  
Rachid El Gharbi ◽  
Alain Fradet

Abstractε-Caprolactone (CL) was reacted with PGA oligomers in ionic liquids in the presence of Ti(OBu)4, both ring-opening polymerization initiator and polyesterification catalyst. 1H and 13C NMR studies showed that the fast polymerization of CL was followed by simultaneous slow polyesterification and ester-interchange reactions leading to random PGA/CL copolyesters after 6 h reaction. The nature of the catalyst and the ionic liquid did not influence much reaction rate. Hydroxyacetyl end-groups appeared to be much less reactive than the corresponding hydroxycaproyl end-groups, which were consumed at the beginning of reaction. The 50/50 and 60/40 oxyacetyl (G)/oxycaproyl (L) (mass-%) copolyesters were amorphous, while copolyesters containing larger amounts of G units were semi-crystalline. The variations of the Tg of all copolyesters versus composition follow the Flory-Fox law.


2002 ◽  
Vol 35 (27) ◽  
pp. 9896-9903 ◽  
Author(s):  
Olivier Coulembier ◽  
Philippe Degée ◽  
Sandrine Cammas-Marion ◽  
Philippe Guérin ◽  
Philippe Dubois

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