CARBOHYDRATE RESEARCH
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2025
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IF 2.5
Yu Yi,Qingying Chen,Ye Zhou,Jianfeng Mei,Yanlu Zhang,Bailong Wang,Guoqing Ying
This study aims to develop an excellent pharmaceutical excipient based on crosslinked hydroxyethyl chitosan (G-HECTS(GA)), designed to exhibit high intrinsic viscosity and superior moisture absorption and retention properties for wound healing applications. Hydroxyethyl chitosan (HECTS) was synthesized from chitosan through a derivatization reaction with bromoethanol under alkaline conditions, achieving a maximum solubility of 6.8 ± 0.2 g/100 g water. The HECTS was further crosslinked with glutaraldehyde (GA) to produce G-HECTS(GA). Structural characterization of the product was performed using Fourier-transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). Key parameters, including crosslinker dosage, reaction time, temperature, and stirring speed, were optimized to evaluate their effects on intrinsic viscosity. The physicochemical properties and wound healing efficacy of G-HECTS(GA) were systematically assessed in a rat wound model. Under optimal conditions (35°C, 25 μL GA, 18 h reaction time), the crosslinked product demonstrated an intrinsic viscosity of 1870 ± 70 mL/g, a moisture retention rate of 39% ± 3% , and a moisture absorption rate of 39.1% ± 0.7% . G-HECTS(GA) rapidly formed a stable film on wound surfaces, effectively absorbing exudates and promoting wound healing. The material exhibited excellent stability, biocompatibility, and antibacterial activity, along with significant anti-inflammatory effects. These properties highlight the potential of G-HECTS(GA) as a high-performance pharmaceutical excipient for hemostatic spray formulations, offering a promising solution for mucosal wound repair and related biomedical applications.
研究领域:
药学
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生物材料
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医学
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
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2021
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IF 6.165
Wenwen Luan,Chunyu Wang,Zuoxiang Zeng,Weilan Xue,Fei Liang,Yu Bai
In this work, the samples of polyvinyl butyral (PVB) with an average degree of acetalization of 79.56% and the average molecular weight of 68.696 kg·mol −1 were prepared by polyvinyl alcohol (PVA) and n-butyraldehyde, catalyzed by p-Toluenesulfonic acid (PTSA). The intrinsic viscosities of PVB were measured in ethanol/water solutions in the temperature range of 293.15–313.15 K. The expansion factors of PVB molecular chains were calculated with the intrinsic viscosity data. The related thermodynamic parameters were derived from the temperature dependence of expansion factors and results indicate that the quality of mixed ethanol/water solvents for PVB solutions decreases with the increase of temperature and the volume fractions of water.
研究领域:
高分子化学
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物理化学
✓ 已验证
产品关联
DOI
高影响因子
POLYMER
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2021
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IF 4.43
Yanru Chen,Linbo Wu,Bo-Geng Li
Poly(1,5-pentylene-co-2,2,4,4-tetramethyl cyclobutylene terephthalate) (PPecBT) random copolyesters glass transition temperature up to 136 °C were synthesized through two-step melting polycondensation of dimethyl terephthalate (DMT) or terephthalic acid (TPA), 2,2,4,4-tetramethyl-1,3-cyclobutanediol (CBDO) and 1,5-pentanediol (PeDO). They were characterized and assessed with intrinsic viscosity , 1 H NMR, DSC , TGA , tensile and impact testing as well as melt foaming observation. Using PeDO as a diol comonomer was helpful to depress CBDO sublimation and pipeline blocking, and to reduce the composition and cis -trans ratio deviations between monomer and copolymer . The presence of PeT repeat unit in PPecBT was beneficial to improve the thermal stability of PPecBT and to reduce undesired melt foaming and volume expansion during melt processing. The T g of these amorphous copolymers is determined by intrinsic viscosity, copolymer composition and cis -cB unit fraction, and a quantitative relationship among them is established. Futhermore, these PPecBTs showed superior tensile ductility as well as strength and modulus.
研究领域:
材料科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
MACROMOLECULES
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2014
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IF 5.927
Jinxian Yang,Lianwei Li,Zongyang Jing,Xiaodong Ye,Chi Wu
A trifunctional initiator with one alkyne, one hydroxyl, and one bromine group was used to construct Br-polystyrene-alkyne-poly(ε-caprolactone)-OH (Br–PS–≡–PCL–OH) diblock copolymer precursor with one terminal alkyne group located at the junction between the two blocks. Further bromination and azidation substitution of the precursor led to a seesaw-type macromonomer azide-polystyrene-alkyne-poly(ε-caprolactone)-azide (N3–PS–≡–PCL–N3). Subsequently, novel hyperbranched copolymers [HB-(PS-b-PCL)n] with independently adjustable PS and PCL branching subchains were prepared by “click” chemistry. All of the linear precursors and hyperbranched copolymers were characterized by FT-IR, 1H NMR, and GPC with triple detectors in detail. It was found that such hyperbranched copolymers are self-similar objects; namely, their intrinsic viscosities ([η]) are scaled to the weight-average molar masses (Mw) as [η] ∼ Mwν, where ν = 0.45 ± 0.01 and 0.48 ± 0.01 for the longer and shorter PS block, respectively. Moreover, the study on the crystallization behavior of unfractionated and fractionated HB-(PS-b-PCL)n copolymers indicated both the crystal size and the degree of crystallinity decrease with the PS subchain length and the overall degree of polymerization, and the remaining oligomer and macromonomer components could facilitate the crystallization of the unfractionated sample. Finally, it was found that the degree of crystallinity decreases dramatically when the weight fraction of fractionated hyperbranched copolymer in macromonomer/hyperbranched copolymer blend films exceeds ∼67%, indicating that the uncrystallizable hyperbranched chains may impose some extra restriction on the crystallization of the macromonomer chains.
研究领域:
高分子化学
·
材料科学
✓ 已验证
DOI
高影响因子
MACROMOLECULES
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2019
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IF 5.997
Nairong Hao,Xiaozheng Duan,Hongjun Yang,Ahmad Umair,Mo Zhu,Muhammad Zaheer,Jinxian Yang,Lianwei Li
This work aims to elucidate how the branching effect of macromonomer influences the polymerization, structural features, and solution properties of ABn long-subchain hyperbranched polymers (LHPs). Our result reveals that compared with linear AB2 macromonomers, star AB3 macromonomers result in the suppression of chain extension, and the enhancement of macromonomer self-cyclization during the preparation of LHPs by “click” polymerization, due to the branching-enhanced steric hindrance effect. The combined triple-detection SEC and stand-alone LLS studies of unfractionated and fractionated AB3 LHPs unambiguously demonstrate their statistically fractal nature. Namely, the intrinsic viscosity ([η]) and radius of gyration (Rg) are scaled to the macromonomer molar mass (Mmacro) and the total molar mass (Mhyper) as [η] = Kη,AB3MhyperνMmacroμ (ν ≃ 0.39, μ ≃ 0, and Kη,AB3 ≃ 0.29 mL/g) and Rg = HR,AB3MhyperαMmacroβ (α ≃ 0.47, β ≃ 0, and HR,AB3 ≃ 3.6 × 10–2 nm). Surprisingly, [η] and Rg are both almost independent of Mmacro (μ ≃ 0 ≃ β), indicating a similar draining property and local segment density for LHPs with different subchain lengths, which is different from the classic AB2 systems (μ ≃ 0.3 and β ≃ 0.1). A comparison of results for ABn LHPs (n = 2, 3) and short-subchain hyperbranched systems indicates that the fractal dimensions (f) for LHPs are generally smaller than short-subchain systems, whereas f is not sensitive to the local segment density or branching pattern. A combination of experimental observation and Langevin dynamics simulation of ABn dendrimers and LHPs further reveals (i) the segment back-folding phenomenon is prominent only for ABn (n ≥ 3) LHPs systems because it is mainly dominated by the macromonomer branching effect, rather than the internal subchain length, and (ii) the trend for segment interpenetration increases remarkably as Mmacro increases for both dendrimers and LHPs. The result also indicates that the unique synergistic effect of segment back-folding and segment interpenetration in AB3 system is the most probable reason for the observed Mmacro independent solution properties. Specifically, because of the unique synergistic effect, small macromonomer/oligomer chains can interpenetrate more easily into hyperbranched oligomer chains composed of longer subchains and subsequently “click” couple with the back-folded segments in the interior space of LHPs, which eventually could lead to a similar draining property and local segment density for AB3 LHPs with different subchain lengths.
研究领域:
高分子化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）