Synthesis of poly(α‐malic acid) and its hydrolysis behavior <i>in vitro</i>

Ouchi, Tatsuro; Fujino, Atsushi

doi:10.1002/macp.1989.021900703

Cited by 108 publications

(93 citation statements)

References 14 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…[3,4,6,7] Examples of functional cyclic diesters and related polyesters are reported in Table 2. Poly(a-malic acid) (1c), which can be regarded as a functional analog of poly(lactic acid), has been prepared by Ouchi and Fujino [15] by ROP of malide dibenzyl ester (1a), a cyclic dimer of b-benzyl malate, followed by debenzylation. Similarly, Kimura et al [16,17] His laboratory (40 people) is concerned with the macromolecular engineering of synthetic polymers based on living/controlled anionic, radical and ring-opening polymerization.…”

Section: Polyesters From Cyclic Diestersmentioning

confidence: 99%

Novel Aliphatic Polyesters Based on Functional Cyclic (Di)Esters

Lou

Detrembleur

Jérôme

2003

Macromol. Rapid Commun.

132

110

View full text Add to dashboard Cite

Recent progress in the chemical synthesis of novel aliphatic polyesters via ring‐opening polymerization of functional cyclic (di)esters are reviewed in this article. Syntheses of these functional aliphatic polyesters are being classified into three groups according to the structure of the cyclic monomers: (i) cyclic diesters, (ii) morpholine‐2,5‐dione derivatives, and (iii) cyclic esters. Progress in the synthesis and polymerization of monomers in each category is reported with an emphasis on controlled synthesis. The recent achievements have enabled the synthesis of a variety of novel aliphatic polyesters, including hydrophilic, halogenated, and unsaturated polyesters. Structure of the most common R‐functionalized cyclic precursors of aliphatic polyesters.magnified imageStructure of the most common R‐functionalized cyclic precursors of aliphatic polyesters.

show abstract

Section: Polyesters From Cyclic Diestersmentioning

confidence: 99%

Novel Aliphatic Polyesters Based on Functional Cyclic (Di)Esters

Lou

Detrembleur

Jérôme

2003

Macromol. Rapid Commun.

132

110

View full text Add to dashboard Cite

show abstract

“…The initial pH values of the nanospheres suspensions were 6.1, 4.5 and 3.6 for the PMLABeloo, PMLABe9oHlo and PMLABesoH2o, respectively, as measured employing a Micro protein resistant combination electrode (Whatman, Maidstone, UK) connected to a pH meter (Coming, Halstead Essex, UK). The pH of the degradation medium was not adjusted to the same value for all the systems since it has been reported that, although strong acidic and alkaline media dramatically affect polyester degradation, pH values in the range 4 to 6 do not have a significant effect on degradation [16,17]. Sodium azide (0.02% w/v) was added as a preservative.…”

Section: Degradation Study Proceduresmentioning

confidence: 99%

Nanospheres prepared from poly(?-malic acid) benzyl ester copolymers: evidence for their in vitro degradation

Stolnik

Garnett

Davies

et al. 1996

J Mater Sci: Mater Med

View full text Add to dashboard Cite

The in vitro degradation of nanospheres perpared from three benzyl ester derivatives of poly (13-malic acid) containing 80, 90 and 100% of benzylated malic acid units was studied. The progressive decrease in the molecular weight of the copolymers was observed as the nanospheres degraded, demonstrating that the degradation under the experimental conditions occurred by a simple hydrolytic cleavage of the ester bond between the monomeric units. The degradation was slow, with the weight average molecular weight decreasing to about 70% of the initial value in 5 months for all the nanosphere systems. A comparison of degradation rates for benzyl ester copolymers with the degradation rate of poly (13-malic acid) homopolymer demonstrated a decreased degradation rate of benzylated copolymers which suggests that the introduction of a pendent benzyl ester function in proximity to the ester bond in the main chain, reduces the rate of the bond cleavage. No significant difference in the degradation behaviour of highly benzylated copolymers, containing 90 and 80% of benzylated malic acid units, and fully benzylated polymer could be detected to prove an autocatalytic role on degradation of the free pendent carboxyl group in the former two copolymers.

show abstract

“…PMA is synthesized in two ways. Many researchers have synthesized the poly-a-malic acid ester or poly-h-malic acid ester through ring-opening polymerization [7,[12][13][14][15][16]. This synthesis is difficult, however, because of the number of steps involved in the reaction cycle, including repeated purification, although these methods yield high molecular weight (HMW) polyesters.…”

Section: Introductionmentioning

confidence: 99%