Article
Polymer Science
Alexis Theodorou, Vasilios Raptis, Chrissie Isabella Maria Baltzaki, Thrassyvoulos Manios, Vagelis Harmandaris, Kelly Velonia
Summary: In this study, we performed synthetic experiments and kinetic modeling calculations to investigate the polycondensation process of lactic acid and the formation of poly(lactic acid) (PLA). The results showed that under optimized conditions, PLLA with a weight-average molecular weight of 161 kDa could be obtained. The kinetic parameters obtained from the optimization accurately reproduced the experimental data.
Review
Polymer Science
Geetu P. Paul, Nagajyothi Virivinti
Summary: Poly(lactic acid) has emerged as a capable biodegradable polymer which can be a suitable alternative to polyolefin. The synthesis methods of polycondensation of lactic acid and ring-opening polymerization of lactide have been extensively discussed in this study. Mathematical modeling has been proven to be an uncomplicated and significant approach to simulate the kinetic model for polymerization.
IRANIAN POLYMER JOURNAL
(2022)
Article
Polymer Science
Yodthong Baimark, Prasong Srihanam, Theeraphol Phromsopha, Yaowalak Srisuwan
Summary: This paper investigates the nucleation efficiency of stereocomplex poly(lactic acid) (scPLA) powder prepared from low-molecular-weight poly(L-lactic acid) (LMW-PLLA) and poly(D-lactic acid) (LMW-PDLA). The addition of scPLA powder improves the crystallization and crystallinity content of high-molecular-weight poly(L-lactide) (HMW-PLLA).
JOURNAL OF POLYMER RESEARCH
(2023)
Article
Polymer Science
Hao Li, Ke Li, Weijun Zhen, Dawei Luo, Ling Zhao
Summary: Poly(lactic acid) (PLA)-beta-cyclodextrin (beta-CD) inclusion complexes (PLA-ICs) were synthesized by ultrasonic coprecipitation with beta-CD and PLA, while vermiculite-PLA-ICs (VMT-PLA-ICs) were synthesized with VMT and PLA-ICs by a coupling method. The resulting PLA/VMT-PLA-ICs nanocomposites showed improved mechanical and thermal properties.
POLYMERS FOR ADVANCED TECHNOLOGIES
(2021)
Article
Chemistry, Multidisciplinary
Michal Wrzecionek, Krzysztof Kolankowski, Agnieszka Gadomska-Gajadhur
Summary: A new polyester poly(glycerol butenedioate) (PGB) with potential modifications in structure was obtained through polycondensation. The optimization of the process was conducted using experimental design, and the two-stage process showed improved structural properties.
Article
Multidisciplinary Sciences
Jihye Park, Ahyun Kim, Byeong-Su Kim
Summary: Despite recent advancements in mechanochemical polymerization, understanding the unique mechanochemical reactivity during the ball milling polymerization process still requires extensive investigations. Here, the authors use solid-state anionic ring-opening polymerization to synthesize polyethers from various functional epoxide monomers. The critical parameters of the monomers are investigated to elucidate the unique reactivity of ball milling polymerization. The controllable syntheses of the desired polyethers are characterized via NMR, GPC, and MALDI-ToF analyses. Interestingly, bulky monomers exhibit faster conversions in the solid-state in clear contrast to that observed for solution polymerization. Particularly, a close linear correlation is observed between the conversion of the ball milling polymerization and melting point of the functional epoxide monomers, indicating melting point as a critical predictor of mechanochemical polymerization reactivity.
NATURE COMMUNICATIONS
(2023)
Article
Materials Science, Composites
Ting-Ni Jen, Kartik Behera, Yen-Hsiang Chang, Fang-Chyou Chiu
Summary: In this study, PLA/TPEE blend and blend-based nanocomposites with CNT as a nanofiller were prepared. Results showed that the presence of CNT significantly improved the properties of the blend, including crystallizability, elongation at break, impact strength, and electrical resistivity. The addition of CNT also led to the formation of a pseudo-network structure, affecting the rheological properties of the blend.
POLYMER COMPOSITES
(2023)
Article
Materials Science, Multidisciplinary
Rong Yang, Hongwei Cao, Pengliang Zhang, Li Chen, Guoxiang Zou, Xin Zhang, Jinchun Li
Summary: Toughened PLA with balanced tensile strength, fast crystallization rate, and great heat resistance was achieved by dynamic vulcanization with unsaturated liquid crystalline polyester (PBDPSM) and free radical initiator dicumyl peroxide (DCP). The addition of PBDPSM significantly increased the elongation at break of PLA, while also accelerating the crystallization rate and improving heat resistance. Highly toughened PLA materials with balanced tensile strength and good heat-resistant properties were realized through this method.
ACS APPLIED POLYMER MATERIALS
(2021)
Article
Polymer Science
Dominik Wolosz, Pawel G. Parzuchowski, Karolina Rolinska
Summary: This work presents an eco-friendly synthetic pathway for the production of non-isocyanate poly(carbonate-urethane)s (NIPCUs) from carbon dioxide and organic carbonates. The obtained NIPCUs exhibit comparable mechanical properties to conventional polyurethane elastomers. The study also investigates the influence of polyurethane structure on the mechanical and thermal properties of the obtained polymers.
Article
Biochemistry & Molecular Biology
Qingwei Liu, Muqing Liu, Yuan Tian, Jie Cheng, Ji Lang, Yi Zhang, Gutian Zhao, Zhonghua Ni
Summary: This study evaluated the radial support performance of PLLA braided stents with different braiding angles. The results showed that the braiding angle is an important parameter affecting the stent's ability to resist radial cyclic loads. Stents with smaller braiding angles had better initial radial support but insufficient durability, while stents with larger braiding angles maintained adequate radial support and suitable ability to resist radial cyclic loads.
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
(2022)
Article
Polymer Science
Qianjin Zhu, Kaixin Chang, Liyan Qi, Xinyi Li, Woming Gao, Qinwei Gao
Summary: In this study, PLLA films were surface-modified using different solutions, leading to changes in their structure and properties. The modification with PDLA weakened the crystal structure of the films, while modification with PDLAG increased the stereocomplex (SC) structure and decreased the homogeneous crystal (HC) structure.
Article
Engineering, Environmental
S. Alijanian, M. J. Zohuriaan-Mehr, M. Esmaeilzadeh, A. Salimi, M. Razavi-Nouri
Summary: Poly (lactic acid) (PLA) is a bioplastic derived from plant sugars that has increasing applications in various industries. However, its brittleness limits its widespread use. This study synthesized biobased tri-armed toughening additives using oligo (lactic acid) and found that adding these modifiers improved the flexibility and mechanical properties of PLA films.
JOURNAL OF POLYMERS AND THE ENVIRONMENT
(2023)
Article
Chemistry, Multidisciplinary
Rong Wang, Xiaojie Sun, Lanlan Chen, Wenbin Liang
Summary: In this study, biodegradable blends of PGA and PBAT with in situ compatibilization using MDI were prepared. The addition of PBAT was found to increase the complex viscosity and storage modulus of the blends, leading to improved compatibility and impact strength. The morphology of the dispersed phase evolved from spherical structure to in situ microfiber, enhancing interfacial adhesion and improving toughness.
Article
Polymer Science
Dongdong Zhou, Miao Xu, Rui Tan, Yanxiao Sun, Zhuang Ma, Jinbin Li, Xue-Hui Dong
Summary: This study precisely controlled chain length heterogeneity using a library of discrete oligo L-lactide (oLLA) and investigated the crystallization behavior of binary blends. Partial segregation occurs when chain length heterogeneity is significant, and co-crystals consisting of non-uniform chains are metastable.
Article
Polymer Science
Yangzhe Hou, Han Jia, Yamin Pan, Chuntai Liu, Changyu Shen, Xianhu Liu
Summary: This study successfully prepared brand-new porous PLA films with enhanced flexibility and heat resistance using blade coating and thermally induced phase separation methods. The resulting blend films showed improved mechanical properties and high porosity, making them suitable for microfiltration, packaging, and modified applications.
Article
Engineering, Chemical
Wichean Khawdas, Yuji Aso, Tomonari Tanaka, Yoko Okahisa, Iori Kazama, Hitomi Ohara
JOURNAL OF CHEMICAL ENGINEERING OF JAPAN
(2020)
Article
Materials Science, Textiles
Kamthorn Intharapichai, Akari Oda, Yoko Okahisa, Hitomi Ohara, Hidekazu Yasunaga
JOURNAL OF FIBER SCIENCE AND TECHNOLOGY
(2020)
Article
Microbiology
Mei Sano, Ryoki Yada, Yusuke Nomura, Takahiro Kusukawa, Hiroshi Ando, Keiji Matsumoto, Kazuhito Wada, Tomonari Tanaka, Hitomi Ohara, Yuji Aso
Article
Chemistry, Physical
Yuji Aso, Mei Sano, Ryoki Yada, Tomonari Tanaka, Takashi Aoki, Hitomi Ohara, Takahiro Kusukawa, Keiji Matsumoto, Kazuhito Wada
Correction
Microbiology
Mei Sano, Ryoki Yada, Yusuke Nomura, Takahiro Kusukawa, Hiroshi Ando, Keiji Matsumoto, Kazuhito Wada, Tomonari Tanaka, Hitomi Ohara, Yuji Aso
Review
Biotechnology & Applied Microbiology
Mei Sano, Tomonari Tanaka, Hitomi Ohara, Yuji Aso
APPLIED MICROBIOLOGY AND BIOTECHNOLOGY
(2020)
Article
Biotechnology & Applied Microbiology
Y. Aso, Y. Nomura, M. Sano, R. Sato, T. Tanaka, H. Ohara, K. Matsumoto, K. Wada
Summary: The study aimed to enhance the production of alkylitaconic acids by Aspergillus niger S17-5 through the addition of caprylic acid as a precursor. Results showed that addition of caprylic acid improved the production efficiency of 9-HHIA and 10-HHIA, especially when added in the mid-growth phase.
JOURNAL OF APPLIED MICROBIOLOGY
(2021)
Article
Biotechnology & Applied Microbiology
R. Sato, T. Tanaka, H. Ohara, Y. Aso
Summary: The disruption of the glpF gene in engineered Escherichia coli increases the intracellular concentration of glycerol, leading to higher 1,3-propanediol (1,3-PDO) production. This disruption also results in a decrease in the by-product acetic acid and enhances the specific growth rate and 1,3-PDO yield from glucose compared to the non-disrupted strain.
LETTERS IN APPLIED MICROBIOLOGY
(2021)
Article
Biotechnology & Applied Microbiology
Naoto Hirose, Iori Kazama, Rintaro Sato, Tomonari Tanaka, Yuji Aso, Hitomi Ohara
Summary: Escherichia coli JM109 (pGV3-SBA) can assimilate starch with the fusion of starch-digesting enzyme alpha-amylase and OprI' lipoprotein anchor on the cell membrane. This study demonstrates the development of microbial fuel cells (MFCs) using this recombinant E. coli and starch as fuel, achieving the highest performance with a 0.4 mM mediator solution in terms of current and power density.
JOURNAL OF BIOSCIENCE AND BIOENGINEERING
(2021)
Article
Biotechnology & Applied Microbiology
Rintaro Sato, Motoyuki Ikeda, Tomonari Tanaka, Hitomi Ohara, Yuji Aso
Summary: This study demonstrates the production of R- and S-1,2-propanediol using engineered Lactococcus lactis for the first time. The addition of mannitol and gluconate in the culture medium enhances 1,2-propanediol production, and a pH-stat approach is used to achieve high concentration of S-1,2-propanediol.
Article
Polymer Science
Sotaro Tsuji, Kazuma Kobayashi, Toshiki Fujii, Hiroaki Imoto, Kensuke Naka, Yuji Aso, Hitomi Ohara, Tomonari Tanaka
Summary: This study reports novel polymers bearing water-soluble tetrafluorobenzene sulfonic acid (sulfoTFB) activated ester groups. The stability of both the polymers and monomers is significantly improved by introducing an alkanediyl linker. The resulting sulfoTFB-bearing polymer is used to synthesize oligosaccharide-grafted glycopolymers with high binding affinity to lectin via post-polymerization modification in water.
MACROMOLECULAR CHEMISTRY AND PHYSICS
(2022)
Article
Biotechnology & Applied Microbiology
Bui Hoang Dang Long, Kotaro Matsubara, Tomonari Tanaka, Hitomi Ohara, Yuji Aso
Summary: In this study, glycerate was produced from glucose using engineered Escherichia coli BW25113. Plasmids carrying genes encoding enzymes involved in glycerol metabolism were introduced into E. coli to enable the production of glycerate. Disruptions of specific genes were performed to enhance glycerate production. The results showed that E. coli carrying these plasmids could produce higher concentrations of glycerate from glucose, and additional modifications improved glycerate production further.
JOURNAL OF BIOSCIENCE AND BIOENGINEERING
(2023)
Article
Biotechnology & Applied Microbiology
Bui Hoang Dang Long, Masahiro Nishiyama, Rintaro Sato, Tomonari Tanaka, Hitomi Ohara, Yuji Aso
Summary: In this study, a novel method for producing glyoxylate from glucose using engineered Escherichia coli BW25113 was proposed. By disrupting certain genes and reinforcing the glyoxylate shunt pathway, a glyoxylate titer of 0.93 ± 0.17 g/L was achieved in flask cultivation. Further overexpression of certain genes resulted in an improvement in glyoxylate production to 1.15 ± 0.02 g/L. Additionally, by expressing a heterologous gene, pyc, the production of glyoxylate was increased to 2.42 ± 0.00 g/L, the highest reported titer and specific productivity of glyoxylate in E. coli to date.
FERMENTATION-BASEL
(2023)
Article
Biotechnology & Applied Microbiology
Iori Kazama, Naoto Hirose, Yuji Aso, Tomonari Tanaka, Hitomi Ohara
Summary: In this study, a bipolar membrane microbial fuel cell (bMFC) was used to generate electricity using cellulose as fuel. The experiment elucidated the mechanism of H+ and OH- reaction in the bipolar membrane, with the dihydrogen phosphate's counter cation serving as the final electron acceptor. The bMFC continuously generated electricity for 20 days.
BIOTECHNOLOGY LETTERS
(2023)
Article
Polymer Science
Sotaro Tsuji, Yuji Aso, Hitomi Ohara, Tomonari Tanaka
JOURNAL OF POLYMER SCIENCE
(2020)