JOURNAL OF APPLIED POLYMER SCIENCE
·
2024
·
IF 2.7
Zhangcheng Gao,Lianfang Feng,Xueping Gu,Jintang Duan,Mingzhe Jiang,Cailiang Zhang
The combination of aromatic and aliphatic structures can endow polyurea with distinct performance advantages. A one-step feeding method is used to synthesize linear hybrid aliphatic/aromatic copolyureas by varying the ratio of m -phenylenediamine (MPD) and polyoxypropylenediamine (D2000) reacting with 4,4′-diphenylmethane diisocyanate (MDI). Real-time Fourier-transform infrared spectrometer monitoring reveals that D2000 exhibits higher reactivity than MPD. Consequently, in the MDI/MPD/D2000 system, D2000 initially reacts with MDI to form an isocyanate-terminated prepolymer, which subsequently reacts with MPD. Compared with the two-step feeding method, this approach successfully eliminates biuret formation and enhances tensile strength. Additionally, decreasing the molar ratio of D2000 to MPD ( λ m ) reduces the size and degree of microphase separation in the polyurea by increasing the ordered hydrogen bonding and benzene conjugation, leading to an increase in tensile strength. Specifically, as λ m decreases from 70 mol% to 30 mol%, the degree of microphase separation decreases from 0.47 to 0.2, causing the tensile strength to rise from 28 to 48 MPa. Further reducing λ m to 30 mol% decreases the degree of microphase separation to 0.16, resulting in an increase in tensile strength to 78 MPa.
研究领域:
材料科学
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化学工程
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DOI
高影响因子
Polymers
·
2022
·Vol. 14
·期 22
·4902
·
IF 4.967
Lei Hua,Xiaodong Wang
New biodegradable aliphatic PLLA-PBA-PLLA copolymers with soft poly(butylene adipate) (PBA) and hard poly(l-lactide) (PLLA) building blocks were synthesized via ring-opening polymerization (ROP). Proton nuclear magnetic resonance (1HNMR) was utilized to confirm the volume fraction of PBA (fPBA) within PLLA-PBA-PLLA. It was found that a PBA midblock (PBA-mid) within PLLA-PBA-PLLA-s (PLLA-PBA-PLLA triblock copolymer with a short PLLA block length) might display lamellar domain structure. However, PBA-mid within PLLA-PBA-PLLA-l (PLLA-PBA-PLLA triblock copolymer with a long PLLA block length) might locate itself as a nanoscale cylindrical domain surrounded by a PLLA continuous phase. Polymorphic crystals of PBA-mid within the PLLA-PBA-PLLA copolymers were formed after melt crystallization at the given temperatures, which were studied by differential scanning calorimetry (DSC) and wide-angle X-ray diffraction (WAXD) analysis. According to the WAXD and DSC analyses, it was interesting to find that the α-type crystal of PBA-mid was favorable to develop in the lower temperature region regardless of the state (crystallization or amorphous) of the PLLA component. Additionally, when the PLLA component was held in its amorphous state, it was easier for PBA-mid within the PLLA-PBA-PLLA copolymers to transform from the metastable β-form crystal to the stable α-form crystal. Furthermore, polarized optical microscopy (POM) photos provided direct evidence of the polymorphic crystals of PBA-mid within PLLA-PBA-PLLAs.Keywords:biodegradable aliphatic;triblock copolymers;polymorphic crystal
研究领域:
材料科学
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高分子化学
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DOI
PubMed
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
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2015
·Vol. 132
·期 23
·
IF 1.768
Zhongfei Qi,Yong Yang,Zhu Xiong,Jun Deng,Ruoyu Zhang,Jin Zhu
A series of aliphatic diacyl adipic dihydrazides (ADHs) with different alkyl moieties were synthesized by the reaction between adipic dihydrazide and acyl chloride. Then these ADHs were solution blended with PLA respectively and were evaluated as nucleating agents. Through the investigation of nonisothermal and isothermal crystallization, it was found that both the crystallization rate and the crystallinity of PLA could be enhanced by adding only 1 wt % of ADHs. Especially for ADH-Oc (ADH-Octyl), the crystallization rate of PLA increased about 4 times at 105°C. Optical morphology showed that and the size of PLA spherulites decreased and the nucleation density increased with the existence of ADH-Oc. Meanwhile, the crystal structure of PLA were not discerniblly affected after the addition of ADHs as found by wide-angle X-ray diffraction. Thus, this study suggested these ADHs compounds are simple and potential nucleating agents to enhance crystallization ability of PLA. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132 , 42028.
研究领域:
材料科学
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高分子化学
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DOI
高影响因子
JOURNAL OF CHROMATOGRAPHY A
·
2021
·
IF 4.759
Yingying Shi,Meiling Qi
This work presents the investigation of two aliphatic polycarbonate diols (CAPC and HAPC) as the stationary phases for capillary gas chromatography (GC). The CAPC and HAPC capillary columns showed moderate polarity and high column efficiency of 3704 – 4545 plates/m measured by n-octanol and naphthalene at 120 °C. It was found that despite their similar chemical compositions, CAPC and HAPC differ largely in their selectivity towards the isomers of alkanes, methylpyridines and xylenes. As demonstrated, the CAPC column exhibits advantageous comprehensive performance over the HAPC column and the commercial PEG column. Particularly, the CAPC column exhibits higher resolving performance towards the isomers indicated above and the Grob mixture than the HAPC column. Also, it shows distinct advantages over the PEG column in separating the Grob mixture, the isomers of diethylbenzenes and cymenes, and practical analysis of chemical products and the essential oil from the leaves of Rhododendron dauricum L. Additionally, the CAPC column has excellent repeatability and reproducibility on analyte retention times with the relative standard deviation (RSD) values in the range of 0.05% – 0.08% for run-to-run, 0.12% – 0.19% for day-to-day and 2.6% – 4.9% for column-to-column, respectively. Its applications to purity test of chemical products and GC–MS analysis of the essential oil demonstrate its promising future for practical GC analyses.
研究领域:
分析化学
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色谱学
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DOI
PubMed
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
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2022
·Vol. 139
·期 28
·e52513
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IF 3.057
Chenxi Lin,Kangzhou Xie,Donglin Tang
Polyureas (PUrs) with excellent properties have been applied widely in many fields. These days attention has been turned to non-isocyanate routes for PUr preparation due to the toxicity and the high cost of isocyanates. Urea is a green chemcial which can be either from urine or from recycled carbon dioxide and ammonia. Here we introduce a urea-based route to prepare PUrs, by melt polycondensation of urea and 1,10-diaminodecane (DA-10) or/and 1,6-diaminohexane (DA-6) without catalyst, solvent, and high pressure. It is difficult to synthesize such thermoplastic PUrs from diisocyanate without any solvent since the melting point of PUr is normally higher than 170°C at which isocyanate is able to react with urea group to form biuret. The thermoplastic PUrs obtained in this study exhibit excellent mechanical and thermal properties. Furthermore, the properties can be adjusted by changing the feed ratio of diamines (DA-6/DA-10). The compression-molded PUrs show even better mechanical properties than ultra-high molecular weight polyethylene (UHMWPE). The values of Young's modulus, strength at break and elongation at break are found to be 230–300 MPa, 40–60 MPa and 200%–400%, respectively (except for PUr-6). Therefore, this facile, non-isocyanate approach provides a viable alternative to the current industrial process for high-performance PUrs.
研究领域:
材料科学
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化学工程
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DOI
高影响因子
JOURNAL OF DRUG DELIVERY SCIENCE AND TECHNOLOGY
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2022
·
IF 5.062
Qida Zong,Shiya Zhou,Jing Ye,Xinxuan Peng,Huiying Wu,Mohan Li,Xuanjiayi Ye,Naixin Tian,Wei Sun,Yinglei Zhai
In addition to various functions, hydrogels used to promote wound healing should also have good biocompatibility , stability and mild degradability. Therefore, we designed and synthesized aldehyde modified aliphatic cyclic carbonate monomer (MTC-Ba). Then the hydrogel matrix (MTC-Ba n -b-PEG 6k -b-MTC-Ba n , MBP) was prepared by ring opening polymerization using polyethylene glycol (PEG) as the initiator and hydrophilicity enhancer. The matrix was covalently linked with the crosslinker adipic acid dihydrazide (ADH) through dynamic hydrazide bond to form a self-healing hydrogel (SH-Gel). At the same time, curcumin was loaded into the hydrogel as a functional model drug. The resulting hydrogel has porosity, injectability, appropriate swelling rate, friendly cell compatibility and safe degradability. In addition, in vivo wound healing evaluation, histological evaluation and immunofluorescence staining showed that this gel could the wound closure, re-epithelium and collagen regeneration. In conclusion, this study provides a new choice for the application of synthetic biodegradable polymer materials in promoting skin wound healing.
研究领域:
生物材料学
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医学工程
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组织工程
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DOI
高影响因子
MACROMOLECULES
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2025
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IF 5.2
Mengru Ding,Lingling Ni,Ying Zheng,Bao Wang,Chengtao Yu,Guorong Shan,Yongzhong Bao,Junfeng Liu,Pengju Pan
Long-spaced aliphatic polyesters are typical sustainable polyethylene (PE)-like polymers. However, the presence of a low amount of ester groups can exert a profound effect on the crystalline structure of such PE-like polymers. Herein, we synthesized a series of long-spaced aliphatic polyesters bearing two proximate ester groups from ethylene glycol (EG) and n-methylene diacids (n = 9–18) and investigated their polymorphic crystallization and phase transitions. We find that the EG-based polyesters exhibit unique crystal polymorphism and phase transition behaviors. They can form a metastable hexagonal phase (form II) with nontilted, extended chain conformations at low temperatures or during rapid cooling but adopt the thermally stable orthorhombic phase (form I) with tilted chain packing at high temperatures or under slow cooling. Form I demonstrates a more densely packed chain structure and displays distinct mechanical properties compared to form II. The metastable hexagonal phase can transform into an orthorhombic phase during heating through a melt-recrystallization mechanism. This study advances the current understanding of the multiphase crystallization of PE-like long-spaced polyesters.
研究领域:
材料科学
·
高分子化学
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产品关联
DOI
高影响因子
JOURNAL OF POLYMERS AND THE ENVIRONMENT
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2025
·
IF 5
Wang Guoqiang,Zhang Mengke,Shi Longqing,Qi Chao,Zhao Zhenxiao,Hu Hongliang,Jin Yujie,Hu Jing
Long-chain polyesters were prepared by melt polymerization using tetradecanedioic acid (TA) and aliphatic diols containing C2-10 as raw materials. The materials were characterised using a range of analytical techniques, including tensile testing, rheological testing, dynamic mechanical analysis (DMA), wide-angle X-ray diffraction (WAXD), differential scanning calorimetry (DSC), gel permeation chromatography (GPC), and thermal gravimetric analysis (TGA). An investigation was conducted to ascertain the impact of diol chain length on a number of characteristics, including mechanical properties, crystalline structures, chemical composition, thermal stability, and thermal transition properties. All polyesters had high weight-average molecular weights (> 57000 g/mol). In addition, the crystallization temperature and melting temperature were affected by the chain length of diols. Poly(ethylene tetradecanedioate) (PETd) had a higher crystallization temperature (69.1 °C) and melting temperature (89.0 °C) compared to the other four polyesters, which may be due to its short-chain structure and the kink structures. All polyesters have the same crystal structure like polyethylene. In addition, poly(ethylene tetradecanedioate) (PETd), poly(butylene tetradecanedioate) (PBTd), and poly(octenyl tetradecanedioate) (POTd) exhibited polyethylene-like mechanical properties with comparable tensile strength and elongation at break. It is anticipated that bio-based polyesters will prove to be a highly promising material.
研究领域:
材料科学
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化学工程
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DOI
高影响因子
BIOSENSORS & BIOELECTRONICS
·
2015
·
IF 6.409
Yangyang Chen,Jiangjiang Zhang,Yanmin Gao,Jaebeom Lee,Hongxia Chen,Yongmei Yin
Since amine compounds have been widespread pollutants in nature and they are extensively used in pharmaceutical industeries and dye manufacturing, it is highly desirable to develop simple, effective and naked-eye available analytical methods for such aliphatic diamines determination. Calixarenes as macrocycles have drawn intensive interests for fields such as biomedicine , supramolecular chemistry and smart materials. Here, instead of the normal complicated modification strategy, a facile and efficient method for one-pot synthesis of calix[4]arene crown ether (CCE4) capped gold nanoparticles (AuNPs) is proposed. The as-prepared CCE4–AuNPs are not only high water dispersity and stability even after storage for 3 months, but also capable of host–guest recognition of diamines in aqueous systems. Size-selective encapsulation of amine group between CCE4 and diamines carry out the aggregation of CCE4–AuNPs. The determination of diamines such as hexamethylenediamine or spermine can be realized by the UV–vis absorbance change and visual color difference.
研究领域:
分析化学
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超分子化学
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纳米材料科学
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DOI
高影响因子
EUROPEAN POLYMER JOURNAL
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2024
·
IF 5.8
Shi-Si Li,Jun-Lin Pan,Xi-Long Chen,Jing Xu,Zi-Long Li,Chunzu Cheng
Long-chain aliphatic polyesters are recognized as the most promising polyethylene mimics in that these materials show comparative physicochemical properties to polyolefins and own the unique merits of degradability and/or recyclability. Nevertheless, the application scenarios of these polymers are rather limited owing to the lack of functional groups. Herein, sulfur atoms are incorporated into the microstructures of long-chain aliphatic polyesters to decipher the variations of physicochemical properties upon replacing specific methylene units by thioether moieties and simultaneously impart polyethylene-like materials with functionalities. First of all, high molecular weight polyesters P1 - P4 and poly(β-thioester)s P5 - P8 were obtained via condensation polymerization and thiol-Michael polyaddition, respectively. As for phase transition behaviors, poly(β-thioester)s show inferior crystallization/melting temperatures and the corresponding enthalpy changes than their polyester counterparts, and a loosely packed crystalline structure should be responsible for such thermal property degradation. It is reasonable that replacing specific methylene units of long-chain aliphatic polyesters by sulfur atoms, the much bulkier functional entities, will definitely cause great disturbance to the regular arrangement of polymer chains. The rapid hydrolytic degradation of poly(β-thioester)s in acidic and alkaline media can be ascribed to the easy penetration of water molecules into their incompact amorphous/crystalline regions. In the meantime, these poly(β-thioester)s exhibit great prospects in noble metal recovery and information encryption (optical anticounterfeiting). For instance, poly(β-thioester) P5 is an excellent adsorbent to abstract gold ions from water due to its outstanding metal coordination capability. Moreover, poly(β-thioester) P5 emits bright blue photoluminescence in concentrated solution and solid state upon UV irradiation as a result of the clustering-triggered through space electron delocalization and rigidified polymer chain conformation.
研究领域:
材料科学
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环境科学
·
化学工程
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产品关联
DOI
高影响因子
Materials Today Communications
·
2024
·
IF 3.7
Bo Liu,Zhigang Yuan,Caizhao Liu,Mingming Sun,Xugang Zhang,Mehdi Derradji,Bin Zhang,Jianhui Li,Ming Zhao,Caiyu Song,Tianyi Xie,Jinzi Li
An aliphatic silicon-containing maleimide monomer 1,1′-((1,1,3,3-tetramethyldisiloxane-1,3-diyl)bis(propane-3,1-diyl))bis(1H-pyrrole-2,5-dione) (TBB) with low melting point (56 °C) was successfully synthesized based on maleic anhydride (MA) and 3,3′-(1,1,3,3-tetramethyldisiloxane-1,3-diyl)bis(propan-1-amine) (BAT). The structure of TBB monomer was determined by FTIR, 1 H NMR and 13 C NMR. Meanwhile, the 3,3′-(1,1,3,3-tetramethyldisiloxane-1,3-diyl)bis(propan-1-amine) (BAT) and 4,4’-Bismaleimidodiphenylmethane (BDM) monomers were respectively prepared from diallyl bisphenol A (DBA), following a 1:0.87 molar ratio, and named TD resins and BD resins. The curing kinetics, thermal stability and processability of TD resins and BD resins were discussed and compared. The activation energy ( E ) value of TD resins was 26.2 % higher than BD resins, resulting in exothermic peak temperature ( T P ) of TD resins was higher than BD resins at different heating rates. Compared with BD resins, the crosslinking density ( v e ) of TD resins was reduced by 93.5 %, which effectively destroyed the thermal stability of TD resins. However, TD resins exhibited outstanding processing window of 195.6 °C. The processing window of TD resins was 110.1 % wider than that of the BD resins, indicating that the former had excellent processability. Overall, this study has enriched the discussion on the curing kinetics of aliphatic bismaleimide resins and has a positive influence on the design of resins monomer with low melting point.
研究领域:
材料科学
·
化学工程
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产品关联
DOI
高影响因子
TALANTA
·
2019
·
IF 4.916
Ling Xia,Yuanqi Du,Xiaohua Xiao,Gongke Li
Aliphatic aldehyde is a type of important organic material and precursor. However, some of them have been proved danger or harmful to health, especially those are occurred in food and cosmetics. Here, we reported a rapid and efficiency one-step membrane protected micro-solid-phase extraction and derivatization (μ-SPE-D) method for selectively determination of trace aliphatic aldehydes in complex cosmetic and food samples by coupling to high-performance liquid chromatography (HPLC). In this method, one-step extraction and derivatization strategy reduced the sample preparation time; membrane protected solid-phase extraction technology eliminated matrix interference; and the efficient sorbent mono-(6-(diethylenetriamine)-6-deoxy)-beta-cyclodextrin- ploy(styrene-divinylbenzene-methacrylic acid) (NH 2 -β-CD-Poly(St-DVB-MAA)) guaranteed the selective adsorption of aliphatic aldehydes. The sorbent, NH 2 -β-CD-Poly(St-DVB-MAA), was prepared via chemical fabrication and optimized carefully. The μ-SPE device, and extraction and derivatization conditions were optimized. The mechanism of extraction and derivatization was also discussed. While coupling to HPLC, the method detection limits were as low as 0.024–2.5 μg/L, and the method quantification limits were 0.081–7.6 μg/L with relative standard deviations (RSDs) in the range of 2.2–7.7%. Finally, this membrane protected μ-SPE-D-HPLC was successfully applied to the real sample analysis. In cosmetics analysis, aliphatic aldehydes were found and quantified in the range of 9.0–750.2 μg/kg, and the recoveries were in the range of 81.7–114.9% with RSDs less than 8.3% from toner and moisturizer samples. Meanwhile, aliphatic aldehydes were found and quantified in the range of 1.3–31.3 μg/kg, and the recoveries were in the range of 80.8–114.4% with RSDs less than 7.1% from fried food samples. Our results proved that only 5 min was needed for extraction and derivatization processes. Furthermore, the method detection limits of formaldehyde were an order of magnitude less than literature reports which reveal excellent selectivity of this membrane protected μ-SPE-D-HPLC method.
研究领域:
分析化学
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食品安全
·
环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）