Polymer Chemistry
·
2014
·Vol. 5
·期 8
·3098-3106
·
IF 5.368
Yu Jin,Yufeng Ji,Xiaojiang He,Suli Kan,Haidong Xia,Binqi Liang,Jia Chen,Hao Wu,Kai Guo,Zhenjiang Li
o-Benzenedisulfonimide (OBS) was demonstrated for the first time to be a safe, recyclable, and water-tolerant Brønsted acidic catalyst for the ring-opening polymerization (ROP) of δ-valerolactone and ε-caprolactone using benzyl alcohol as the initiator. The polymerizations proceeded to afford poly(δ-valerolactone) and poly(ε-caprolactone) with controlled molecular weights and narrow polydispersities. The kinetics and chain extension experiments were carried out to confirm the controlled/living fashion of the polymerizations. In addition, 1H NMR and MALDI-TOF MS measurements strongly indicated that the initiator residue was incorporated into the obtained polymers. Furthermore, well-defined poly(δ-valerolactone)-block-poly(ε-caprolactone) has been successfully synthesized via OBS-catalyzed ROP.
研究领域:
高分子化学
·
材料科学
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DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2022
·
IF 8.025
Wenjian Huang,Xin Wen,Jin Zhou,Xuzhen Zhang
Poly (L-lactic acid) (PLLA) based copolymers modified with δ -valerolactone (DVL) through random copolymerization (PVLA-R) and block copolymerization (PVLA-B) with various DVL content were prepared to investigate their degradation regulation and mechanism. Chemical structure , thermal properties , hydrophilicity , crystallization as well as the crystal defects of the obtained copolymers were respectively confirmed. Degradation regulation of both PVLA-R and PVLA-B, such molecular weight and pH value changes of PLLA based copolymers were investigated via vitro degradation method. In order to further explore the degradation principle of the two copolymers , their degradation residues at different stages were systematically studied. The addition and increasing content of DVL disturbs the regularity of original PLLA molecular structure, resulting in accelerating degradation of copolymers . Compared with amorphous region, the crystalline region of both two copolymers has better corrosion resistance , which could be confirmed by increased melting point and crystallinity of both PVLA-R and PVLA-B degradation residues. PVLA-B copolymers show relatively superior degradation resistance mainly due to their higher molecular weight , crystallinity and hydrophobic index than PVLA-R copolymers.
研究领域:
材料科学
·
生物医学工程
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DOI
高影响因子
EUROPEAN POLYMER JOURNAL
·
2018
·
IF 3.741
Songquan Xu,Hui Zhu,Zhenjiang Li,Fulan Wei,Yu Gao,Jiaxi Xu,Haixin Wang,Jingjing Liu,Tianfo Guo,Kai Guo
H-bond donor (HBD) and base co-catalysis achieved great success in ring-opening polymerization (ROP). Parallel H-bond donor and Brønsted acid (HBD–BA) cocatalysis has been scarcely explored in ROPs. In developing the HBD–BA catalysis in to versatile toolbox for ring-opening polymerizations of wider scope and better control, tunable HBDs including boronate pinacol ester urea (BU), urea (U), and thiourea (TU) were evaluated in cooperation with trifluoroacetic acid (TFA) in HBD–BA catalytic mode. Each of the HBD–TFA co-catalyst promoted ROPs of δ-valerolactone (VL) and ε-caprolactone (CL) successfully. The catalytic performances of the HBD–TFA on the HBD part was in an order of BU > U > TU to their corresponding ROPs of VL and CL. The turnover frequencies of the catalyzed ROPs of VL and CL by BU–TFA was twice as that of TFA. The ROPs afforded homopolymers with predicted molecular weights (PVL, M n,NMR = 2.51–9.92 kg mol −1 ; PCL, M n,NMR = 2.51–11.1 kg mol −1 ) and narrow dispersities (PVL, Đ ≤ 1.16; PCL, Đ ≤ 1.18) by ratios of monomer to initiator from 20 to 100. The obtained polymers were analyzed by 1 H NMR, 13 C NMR, and MALDI-ToF MS, the results indicated the high chain-end fidelity. Chain extension experiments were conducted by a first ROP of VL/CL and second ROP of CL/VL with precise molecular weights (from 2.98 kg mol −1 to 6.15 kg mol −1 ) and narrow dispersities below 1.18. The kinetics plots showed a distinct first order relationship between ln([VL] 0 /[VL]) versus the reaction time, it indicated the controlled nature of the catalytic ROP. NMR titrations supported the proposed mechanism that HBD associated with TFA and promoted the cationic polymerization.
研究领域:
高分子化学
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催化化学
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DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2024
·Vol. 142
·期 2
·e56337
·
IF 2.7
ZiXuan Wang,Hao Zheng,Zhengchun Cai,Haian Xia
Bio-based plastics have received much attraction because they are an alternative to petroleum-based plastics in recent years. Among them, aliphatic polyesters have garnered the most attention due to their excellent properties. Polyester is primarily synthesized through ring opening polymerization of monomer, and the catalysts used are mostly synthesized through “click” reaction in the laboratory, which exhibits inferior activity and little commercial value. Herein, a facile approach was developed for the synthesis of high molecular-weight cyclic aliphatic polyesters, specifically poly(valerolactone- co -caprolactone) with varying compositions. This involved the ring-opening copolymerization of ε-caprolactone (ε-CL) and δ-valerolactone (δ-VL) in the absence of an initiator with commercial hydrogen bond donor triclorocarban and an organic base. The structure and properties of the prepared cyclic polyester were investigated using GPC, 13 C NMR, 1 H NMR, MALDI-TOF mass spectrometry, TOF-SIMS mass spectrometry, differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and X-ray diffraction (XRD) techniques. The results show that the molecular weight of cyclic polyester can rapidly exceed 40 kDa, with a PDI of approximately 1.10. In comparison to linear polyester, it has a higher melting point and superior thermodynamic properties, thus presenting greater application potential. Finally, based on nuclear magnetic resonance titration, the potential catalytic processes and mechanisms of bimolecular systems on monomers in different environments were discussed. This study not only offers new insights into the structure and properties of cyclic polyesters, but also presents novel bimolecular catalytic systems using commercial urea hydrogen bond donors for the synthesis of cyclic polymer polyesters.
研究领域:
材料科学
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有机化学
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产品关联
DOI
高影响因子
RSC Advances
·
2016
·Vol. 6
·期 51
·45791-45801
·
IF 3.289
Yingying Ren,Zhiyong Wei,Tong Wu,Yufei Bian,Xuefei Leng,Cheng Zhou,Yang Li
A large diversity of tailor-made linear-comb and star-comb poly(δ-valerolactone)s (PVL) have been obtained with hydroxylated polybutadiene (HPB) as a macroinitiator and 1,5,7-triazabicyclo-[4.4.0]dec-5-ene (TBD) as a catalyst by a simple “one-step” method. The critical content of this research was to explore systematically the differences in the physicochemistry properties between highly branched PVLs and linear PVLs, including the intrinsic viscosity, rheological properties, and crystallization and melting behavior. Studies of solution behavior and melting behavior elucidated that intrinsic viscosities in solution and complex viscosities in the bulk for comb branched PVLs were much lower compared with their linear and star counterparts. Both WAXD and DSC analysis of PVLs with different topological structures indicated that the comb branched architectures do not alter the structures of the PVL crystallites, but markedly improve the crystallization behavior, e.g. higher crystallinities. Moreover, the influence of the molecular weight of a single arm on the thermal properties and crystallization properties of the obtained linear-comb PVLs was explored. The results demonstrated that the crystallization temperatures (Tcs), melting temperatures (Tms) and crystallinities increased with the increase of molecular weight of a single arm. As such, a structure–property correlation is expected to be constructed which is of great practical importance in the syntheses and applications of highly branched polymers (HBPs).
研究领域:
高分子化学
·
材料科学
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产品关联
DOI
高影响因子
JOURNAL OF POLYMER SCIENCE
·
2020
·Vol. 58
·期 24
·3411-3418
·
IF 0
Yang Chen,Wenhao Xiao,Jie Zhang,Minglu Bu,Xiaoqing Zhang,Anfu Chen,Jinbao Xu,Caihong Lei
An iminotris(dimethylamino)phosphorane (HMP 1 ) phosphazene superbase has been anchored onto poly(hexachlorocyclotriphosphazene- co -4,4′-sulfonyldiphenol) (PZS)-coated Fe 3 O 4 magnetic nanoparticles (MNPs) through efficient phosphorous-chloride (from PZS surface) and imino (from HMP 1 ) reaction. Subsequently, these novel heterogeneous Fe 3 O 4 @PZS@HMP 1 catalysts have been successfully utilized in the ring-opening polymerization of ε -caprolactone ( ε -CL) and δ -valerolactone ( δ -VL). Notably, such catalysts can be easily removed from the reaction mixture and reused 3 times without obvious activity loss. Graphical Phosphazene superbase was anchored onto poly(hexachlorocyclotriphosphazene- co -4,4′-sulfonyldiphenol) (PZS)-coated Fe 3 O 4 nanoparticles as immobilized catalyst for ring-opening polymerization and its catalytic activity, recoverability and recyclability was investigated.
研究领域:
材料科学
·
催化化学
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DOI
CHINESE JOURNAL OF POLYMER SCIENCE
·
2024
·
IF 4.1
Liu Xin-Yu,Zhu Liang,Jie Su-Yun,Li Bo-Geng
Due to their excellent biocompatibility and biodegradability, aliphatic polyesters are widely used in the biomedical, packaging and agricultural fields, which are usually accessed by the ring-opening polymerization (ROP) of lactones and the catalysts particularly play an important role. Herein a series of quinolinyl-urea catalysts have been synthesized via the reaction between isocyanate and aminoquinoline with an amino group at different substitution positions and characterized. In combination with 7-methyl-1, 5, 7-triazabicyclo[4,4,0]dec-5-ene (MTBD) as a cocatalyst and benzyl alcohol (BnOH) as an initiator, 1-(3,5-bis(trifluoromethyl)phenyl)-3-(quinolin-3-yl)urea ( 3-QU ) was observed to be most active for the ROP of δ -valerolactone ( δ -VL). The polymerization conditions were optimized by varying the type of organic base, catalyst concentration and reaction temperature. By changing the ratio of [M] 0 /[I], linear polyvalerolactones (PVLs) with different molecular weights and narrow molecular weight distribution were prepared. The kinetic and chain extension experiments were carried out to prove the “living”/controllable feature. And the NMR experiments were used to support the proposal of possible mechanism.
研究领域:
材料科学
·
生物医学工程
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产品关联
DOI
高影响因子
JOURNAL OF POLYMER SCIENCE
·
2020
·Vol. 58
·期 15
·2108-2115
·
IF 0
Rui Feng,Suyun Jie,Pierre Braunstein,Bo-Geng Li
The ring-opening copolymerization of ε-caprolactone and δ-valerolactone was carried out under solvent-free conditions with a pyridyl-urea ( 6C-PU )/7-methyl-1,5,7-triazabicyclo[4.4.0]dec-5-ene catalytic system by premixing two monomers, yielding gradient copolyesters with cyclic and linear structures in the absence or presence of an initiator, respectively. The random and block copolyesters of these two monomers were also prepared for comparison. The results of 1 H and 13 C NMR spectra determined the linear and cyclic structure of copolymers. The kinetic experiment was used to determine the consuming rates of two monomers during the polymerization. The topologies and thermal properties of all the copolymers were characterized and compared by NMR and DSC. Graphical Gradient copolymers with cyclic and linear topologies have been prepared via the ring-opening copolymerization of ε-caprolactone and δ-valerolactone in the absence or presence of BnOH catalyzed by a pyridyl-urea ( 6C-PU )/7-methyl-1,5,7-triazabicyclo[4.4.0]dec-5-ene system. The structure and thermal properties of copolymers with different composition or different sequential distribution were also investigated.
研究领域:
高分子化学
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材料科学
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DOI
Catalysis Science & Technology
·
2020
·Vol. 10
·期 22
·7555-7565
·
IF 5.721
Chenlin Ji,Suyun Jie,Pierre Braunstein,Bo-Geng Li
Aliphatic polyesters are a class of biorenewable, biocompatible, and biodegradable materials. The ring-opening polymerization (ROP) of lactones is one of the most powerful methods to access these materials. A novel series of benzoheterocyclic urea catalysts has been synthesized and characterized. When employed in the ROP of δ-valerolactone (δ-VL) in combination with 7-methyl-1,5,7-triazabicyclo[4.4.0]dec-5-ene (MTBD), a fast and “living”/controlled feature was observed in both solvent-free polymerization and solution polymerization, which was proved by kinetic and chain extension experiments. With benzyl alcohol as an initiator, polyvalerolactones (PVLs) were obtained with different molecular weights and narrow molecular weight distributions. In addition, the PVLs with different topological structures were prepared by varying the initiators. The structure and thermal properties of resulting polymers were determined by NMR, GPC and DSC analyses. A possible mechanism was also proposed on the basis of NMR analysis.
研究领域:
材料科学
·
有机化学
✓ 已验证
产品关联
DOI
高影响因子
Polymers
·
2025
·Vol. 17
·期 8
·1030
·
IF 4.9
Chaoqun Wang,Tong Wu,Yidi Li,Jie Liu,Yanshai Wang,Kefeng Wang,Yang Li,Xuefei Leng
Amphiphilic block copolymers with complex topologies (e.g., star and brush topologies) have attracted significant attention in drug delivery owing to their superior performance over linear micelles. However, their precise synthesis and structure–property relationships require further investigation. In this study, hydroxylated polybutadiene with adjustable topology and hydroxyl group density was employed as a macroinitiator to synthesize well-defined amphiphilic poly (ethylene oxide)- b -poly( ε -caprolactone- ran - δ -valerolactone) (PEO- b -P(CL- ran -VL)) copolymers via ring-opening polymerization (ROP). A series of linear, star, linear–comb, and star–comb copolymers were prepared as curcumin-loaded micellar carriers for the study. The self-assembly behavior, drug encapsulation efficiency, and in vitro release profiles of these copolymers in aqueous environments were systematically investigated. The results demonstrated that increasing the branch length of star–comb copolymers effectively reduced micelle size from 143 to 96 nm and enhanced drug encapsulation efficiency from 27.3% to 39.8%. Notably, the star–comb architecture exhibited 1.2-fold higher curcumin encapsulation efficiency than the linear counterparts. Furthermore, the optimized star–comb nanoparticles displayed sustained release kinetics (73.38% release over 15 days), outperforming conventional linear micelles. This study establishes a quantitative structure–property relationship between copolymer topology and drug delivery performance, providing a molecular design platform for programmable nanocarriers tailored to diverse therapeutic requirements of various diseases.
研究领域:
药剂学
·
高分子化学
·
纳米医学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
MACROMOLECULES
·
2018
·
IF 5.914
Zhitao Hu,Yi Chen,Huahua Huang,Lixin Liu,Yongming Chen
This article demonstrates the synthesis of a new kind of cationic poly(δ-valerolactone) with primary amino groups at α-positions (poly(α-NH2-VL)) via ring-opening polymerization (ROP) of α-NHBoc-valerolactone (α-NHB-VL) followed by a simple deprotection reaction. The ROP of α-NHB-VL using benzyl alcohol as an initiator and DBU/TU (1,8-diazabicyclo[5.4.0]undec-7-ene/thiourea) as a catalytic system in THF at room temperature afforded poly(α-NHB-VL) with narrow molecular weight distribution. The 1H NMR and MALDI-TOF MS analysis of poly(α-NHB-VL) indicated that each polymeric chain was capped by the initiator. Kinetic experiments confirmed the living nature of the DBU/TU-catalyzed ROP of α-NHB-VL in THF. The copolymerization result indicated that the polymerization activity of α-NHB-VL is comparable to that of ε-caprolactone (CL) and VL. In addition, block copolymers containing poly(α-NHB-VL) were successfully synthesized regardless of whether hydrophilic PEG or hydrophobic PCL was used as the macroinitiator. Moreover, water-soluble poly(α-NH2-VL) was obtained by treatment with trifluoroacetic acid (TFA). It was found that poly(α-NH2-VL) degraded more slowly at pH 5.5 than at pH 7.4 through a hydrolysis kinetics study.
研究领域:
高分子化学
·
材料科学
·
生物医学工程
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产品关联
DOI
高影响因子
APPLIED ORGANOMETALLIC CHEMISTRY
·
2019
·Vol. 33
·期 5
·e4890
·
IF 3.259
Farah Naz,Bibimaryam Mousavi,Zhixiong Luo,Christia Jabbour,Philippe M. Heynderickx,Somboon Chaemchuen,Francis Verpoort
A series of spray dried zeolitic imidazolate frameworks (ZIFs = ZIF-8, ZIF-67, and Zn/Co-ZIF) are used as a catalyst for the bulk ring-opening polymerization of δ-valerolactone without any co-catalyst to generate polyvalerolactone. Interestingly, using the same catalyst under the same reaction conditions could manipulate the structure of the product polymer, and thus its physical properties. Thus, using a dried substrate leads to the formation of the cyclic polymer while a linear polymer was formed on using the commercially available substrate. An activated monomer mechanism has been suggested where the propagating zinc alkoxide undergoes an intramolecular transesterification to release cyclic or linear polyvalerolactone. The ROP of δ-VL without drying shows that the polymeric zwitterions have little tendency to cyclize in the presence of moisture. At 140 °C, ZIF-8 shows a superior catalytic activity resulting in the production of cyclic polyvalerolactone having a high molecular weight as compared to ZIF-67 or Zn/Co-ZIF due to the presence of highly active sites. The catalyst could be recycled and reused without any significant loss of catalytic activity.
研究领域:
高分子化学
·
材料科学
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催化化学
·
生物可降解材料
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）