Article
Biochemistry & Molecular Biology
Maxim V. V. Zabalov, Badma N. N. Mankaev, Mikhail P. P. Egorov, Sergey S. S. Karlov
Summary: Density functional theory simulations were conducted to investigate the ring-opening copolymerization of epsilon-caprolactone and L-lactide using a novel gallium complex with an aminobis(phenolate) ligand. The results show that the copolymerization with this catalyst exhibits a faster polymerization rate for epsilon-caprolactone than for L-lactide, suggesting the formation of a predominantly block copolymer composed of epsilon-caprolactone and L-lactide.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2022)
Article
Chemistry, Physical
Rou-Rong Su, Prasanna Kumar Ganta, Che-An Cheng, Yu-Ting Hu, Yung-Chi Chang, Chun-Juei Chang, Shangwu Ding, Hsuan-Ying Chen, Kuo-Hui Wu
Summary: A series of zinc complexes with ethyl salicylates were synthesized and their catalytic activity in the polymerization of epsilon-caprolactone and L-lactide was investigated. Ligands with substituents at the ortho position of phenolates promoted the catalytic activity in CL polymerization, while ligands with electron-donating substituents promoted the activity in LA polymerization. Density functional theory calculations revealed the mechanism behind the polymerization.
MOLECULAR CATALYSIS
(2023)
Review
Chemistry, Inorganic & Nuclear
Ling-Jo Wu, Wei Lee, Prasanna Kumar Ganta, Yu-Lun Chang, Yung -Chi Chang, Hsuan-Ying Chen
Summary: Multinuclear metal complexes can enhance the catalytic activity of ROP catalysts, but the distance between catalytic metal centers and the resonance of ligands play important roles in the catalytic reaction. This review focuses on recent studies of multinuclear metal catalysts in ROP and compares their catalytic activity with mononuclear metal catalysts.
COORDINATION CHEMISTRY REVIEWS
(2023)
Article
Polymer Science
Yutthana Wongnongwa, Setsiri Haesuwannakij, Kwanchanok Udomsasporn, Phongnarin Chumsaeng, Anucha Watcharapasorn, Khamphee Phomphrai, Siriporn Jungsuttiwong
Summary: Polymerization of biodegradable lactide and lactone has been extensively investigated. Density functional theory calculations were used to study the initiation and first propagation for ring-opening polymerization mechanisms of L-lactide (LA) and e-caprolactone (CL) on aluminum complexes. The results showed that the ROP mechanisms of LA and CL on different catalysts were classified into homopolymerization and copolymerization. The understanding gained in this study could contribute to the development of high-performance catalysts for biodegradable lactide and lactone ROP reactions.
Article
Polymer Science
Chun-Juei Chang, Wei Lee, Yu-Chi Liou, Yu-Lun Chang, Yi-Chun Lai, Shangwu Ding, Hsuan-Ying Chen, Hsing-Yin Chen, Yung-Chi Chang
Summary: The study demonstrated that dinuclear aluminum complexes exhibited higher catalytic activity than mononuclear aluminum complexes, particularly those with 1,3-substituted phenyl ligands. One Al atom in the dinuclear Al system acted as an electron-withdrawing group, influencing the other Al atom through associated aromatic ligands, thereby enhancing catalytic activity for the ROP of CL.
EUROPEAN POLYMER JOURNAL
(2022)
Article
Chemistry, Inorganic & Nuclear
Damilola C. Akintayo, Wisdom A. Munzeiwa, Sreekantha B. Jonnalagadda, Bernard Omondi
Summary: A series of nine Zn(II) carboxylate complexes stabilized by monodentate pyridyl Schiff base ligands were synthesized and characterized. The molecular structures of these complexes were determined using single-crystal X-ray diffraction and found to have different nuclearities. These carboxylate complexes displayed good catalytic activity in the ring-opening polymerization of epsilon-caprolactone and rac-lactide at elevated temperatures. The catalytic activity was influenced by the nuclearity and coordination geometry of the complexes.
INORGANICA CHIMICA ACTA
(2022)
Article
Biochemistry & Molecular Biology
Ahmed Abd El-Fattah, Elizabeth Grillo Fernandes, Federica Chiellini, Emo Chiellini
Summary: Amphiphilic copolymers with interesting architecture and tunable properties are promising materials for biomedical applications. Enzymatic catalysis provides a suitable alternative for the preparation of these materials without the use of toxic catalysts. The structure-property relationship of copolymers was studied by varying the molecular weight of Pluronic (EPE) and the molar ratios between ε-caprolactone monomer and EPE macro-initiator (M/In). The obtained copolymers were chemically characterized and their morphologies evaluated. The results showed a correlation between the differential scanning calorimetry data and X-ray diffraction data, suggesting the importance of the central block length in crystal formation. Preliminary cytotoxicity experiments confirmed the non-toxic nature of the copolymers.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2022)
Article
Polymer Science
Martin Castillo-Santillan, Jose Roman Torres-Lubian, Antonio Martinez-Richa, Silvia T. Huerta-Marcial, Maria C. Gutierrez, Katja Loos, Maria Guadalupe Perez-Garcia, Josue D. Mota-Morales
Summary: This work provides new insights into the ring-opening polymerization of L-lactide and e-caprolactone, leading to the synthesis of polymer blends and a block copolymer. The selection of parameters and catalysts allows for the production of polyesters with tunable properties and controlled degradation profiles.
Article
Chemistry, Physical
Jonathan E. Chellali, Alexander K. Alverson, Jerome R. Robinson
Summary: This study reports a new class of Zn catalysts that exhibit high activity and stability in the ring-opening polymerization of lactide. Mechanistic studies revealed a quantitative structure-function relationship between the steric profile of the catalyst's reaction site and its activity, providing important insights for the design of homogeneous catalysts.
Article
Chemistry, Inorganic & Nuclear
Shweta Sagar, Kulsum Bano, Alok Sarkar, Kuntal Pal, Tarun K. Panda
Summary: A novel sulfur-supported magnesium complex was developed as a catalyst for ring-opening polymerization of rac-lactide and epsilon-caprolactone. This catalyst showed high selectivity for rac-lactide polymerization, resulting in isoselective PLA with a P-i value of 0.77. The polymerization proceeded under mild reaction conditions without the need for an external initiator, and the resulting polyesters exhibited good control over the molecular weight.
EUROPEAN JOURNAL OF INORGANIC CHEMISTRY
(2022)
Article
Polymer Science
Watcharee Funfuenha, Winita Punyodom, Puttinan Meepowpan, Wanich Limwanich
Summary: Microwave irradiation was successfully used to improve the solvent-free ring-opening polymerization of ε-caprolactone with different n-butyltin(IV) chloride initiators. The performance of these initiators was compared to the conventional tin(II) 2-ethylhexanoate. The presence of chlorine atom in the n-butyltin(IV) chloride initiators played a significant role in controlling the molecular weight of the polymer.
Article
Polymer Science
Monique J. Leite, Tamara Agner, Fabricio Machado, Brenno A. D. Neto, Pedro H. H. Araujo, Claudia Sayer
Summary: This study utilized an iron-containing imidazolium-based ionic liquid as a catalyst to efficiently catalyze the ring-opening polymerization of epsilon-caprolactone under mild reaction conditions, resulting in the synthesis of polycaprolactones with high yields and narrow molecular weight distributions.
JOURNAL OF POLYMER RESEARCH
(2022)
Article
Polymer Science
Hans R. Kricheldorf, Steffen M. Weidner, Felix Scheliga
Summary: Alcohol-initiated ring-opening polymerizations of L-Lactide were conducted, and it was found that caprylate exhibited the highest catalytic activity among the three catalysts tested. Increasing the LA/Cat ratio resulted in higher fractions of cyclic polymers.
JOURNAL OF POLYMER SCIENCE
(2022)
Article
Polymer Science
Yuliya A. Piskun, Evgenii A. Ksendzov, Anastasiya V. Resko, Mikhail A. Soldatov, Peter Timashev, Hongzhi Liu, Irina V. Vasilenko, Sergei V. Kostjuk
Summary: The bulk ring-opening polymerization of epsilon-caprolactone was studied using a phosphazene-containing porous polymeric material (HPCP) as the catalyst at high reaction temperatures (130-150 degrees). HPCP, in combination with benzyl alcohol as an initiator, enabled the controlled living ROP of epsilon-caprolactone, producing polyesters with controlled molecular weights up to 6000 g/mol and moderate polydispersity. Higher molecular weight poly(epsilon-caprolactone) was obtained at a lower temperature of 130 degrees C. The HPCP catalyst demonstrated high thermal and chemical stability, allowing for reuse in multiple cycles without significant loss in efficiency. A tentative mechanism involving the activation of the initiator through the basic sites of the catalyst was proposed.
Article
Chemistry, Physical
Federica Tufano, Federica Santulli, Fabia Grisi, Marina Lamberti
Summary: Two zinc complexes with NHC ligands were synthesized and studied for their behavior in the Ring-Opening Polymerization of lactides, showing efficiency as initiators with molecular weights dependent on cocatalysts. Microstructural analysis revealed enriched heterotactic PLA, with kinetic parameters compared between different conditions and reactions showing pseudo-first-order dependence on monomer concentration. Reactivity studies aimed to uncover the active species in polymerization processes with different catalytic systems, including zinc complexes alone or in combination with neutral or ionic cocatalysts.
