Membranes
·
2020
·Vol. 10
·期 12
·431
·
IF 3.094
Yijie Ren,Hongxia Zhou,Jin Lu,Sicheng Huang,Haomiao Zhu,Li Li
Diseases and complications related to catheter materials are severe problems in biomedical material applications, increasing the infection risk and medical expenses. Therefore, there is an enormous demand for catheter materials with antibacterial and antifouling properties. Considering this, in this work, we developed an approach of constructing antibacterial surfaces on polyurethane (PU) via surface-initiated atom transfer radical polymerization (SI-ATRP). A variety of cationic polymers were grafted on PU. The biocompatibility and antifouling properties of all resulting materials were evaluated and compared. We also used a theoretical algorithm to investigate the anticoagulant mechanism of our PU-based grafts. The hemocompatibility and anti-biofouling performance improved at a 86–112 μg/cm2grafting density. The theoretical simulation demonstrated that the in vivo anti-fouling performance and optimal biocompatibility of our PU-based materials could be achieved at a 20% grafting degree. We also discuss the mechanism responsible for the hemocompatibility of the cationic brushes fabricated in this work. The results reported in this paper provide insights and novel ideas on material design for applications related to medical catheters.Keywords:polyurethane;cationic brushes;graft density;hemocompatibility;anti-biofouling;catheter
研究领域:
生物医学工程
·
材料科学
·
高分子化学
✓ 已验证
DOI
PubMed
高影响因子
COMPOSITES SCIENCE AND TECHNOLOGY
·
2013
·
IF 3.328
Yuxin Li,Yibin Li,Yujie Ding,Qingyu Peng,Chao Wang,Rongguo Wang,Thirumany Sritharan,Xiaodong He,Shanyi Du
Carbon nanotubes (CNTs) were chemically grafted onto carbon fiber (CF) by 1,3-propodiamine bridging. The grafting density could be tuned by reaction time and concentration of 1,3-propodiamine. The fourier transform infrared spectra and X-ray photoelectron spectroscopy confirmed the chemical bonding nature between CNT and CF. The interfacial shear strength of the hierarchical composites is highly dependent on the grafting density, which could be two times that of as-received composite. The interfacial enhancement mechanism was also analyzed.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
Polymer Chemistry
·
2020
·Vol. 11
·期 38
·6206-6214
·
IF 5.342
Heyu Shen,Xuefei Leng,Li Han,Pibo Liu,Chao Li,Songbo Zhang,Lan Lei,Hongwei Ma,Yang Li
Polymer properties are usually affected by both the chain structure and aggregate structure. This has impeded studies of the relationship between the chain structure and polymer properties. However, for surface properties, the chain structure revealed a significant influence, as the chains are simply arranged as thin layers on the surface. Hence, a controlled chain structure is important to the film surface. Herein, sequence-determined fluoropolymers were synthesized using living anionic polymerization and an epoxy-amine reaction. They had definite perfluoroalkyl chain lengths and a determined sequence distribution (i.e. statistical average distribution). Based on these well-prepared fluoropolymers, the structure–property relationship was studied in detail. This indicated that the long perfluoroalkyl chain led to a low surface tension and slight surface reconstruction; meanwhile, the sequence distribution affected the sensitivity of the structural changes and the surface reconstruction. Finally, based on molecular dynamic simulations and X-ray photoelectron spectroscopy (XPS) analysis, four assembled structural models, called cluster models, were proposed to describe the assembled behaviours of the perfluoroalkyl chains at the surface.
研究领域:
高分子科学
·
表面化学
·
材料科学
·
物理化学
·
纳米科技
✓ 已验证
DOI
高影响因子
Small
·
2023
·Vol. 19
·期 20
·2207821
·
IF 13.3
Zelin Wang,Xidong Lin,Youchen Tang,Dongtian Miao,Junlong Huang,Yan Lu,Shaohong Liu,Ruowen Fu,Dingcai Wu
Carbon-based polymer brushes (CBPBs) are an important class of functional polymer materials, which synergistically combine the advantageous properties of both carbons and polymers. However, the conventional fabrication procedures of CBPBs involve tedious multistep modification, including preoxidation of carbon substrates, introduction of initiating groups, and subsequent graft polymerization. In this study, a simple yet versatile defect-engineering strategy is proposed for the efficient synthesis of high-grafting-density CBPBs with highly stable C C linkages via free radical polymerization. This strategy involves the introduction and removal of nitrogen heteroatoms in the carbon skeletons via a simple temperature-Fmed heat treatment, leading to the formation of numerous carbon defects (e.g., pentagons, heptagons, and octagons) with reactive C=C bonds in the carbon substrates. The as-proposed methodology enables the facile fabrication of CBPBs with various carbon substrates and polymers. More importantly, the highly grafted polymer chains in the resulting CBPBs are tethered with the carbon skeletons by robust C C bonds, which can endure strong acid and alkali environments. These interesting findings will shed new light on the well-orchestrated design of CBPBs and broaden their applications in various areas with fascinating performances.
研究领域:
材料科学
·
聚合物化学
·
表面化学
✓ 已验证
DOI
高影响因子
MACROMOLECULES
·
2022
·
IF 6.057
Jianing Zhou,Jinxian Yang,Muhammad Waqas Ishaq,Lianwei Li
Exploring the difference in the topology–structure–conformation relationship for linear and cyclic graft polymers is an interesting topic. In this work, two libraries of linear graft (l-PPA-g-PS, with a linear backbone) and cyclic graft (c-PPA-g-PS, with a cyclic backbone) polystyrenes with low ratios of the backbone-to-sidechain contour length (rc, from 1.26 to 6.22) and various grafting densities (σ, from 0.16 to 0.86) have been studied as models. Atomic force microscopy (AFM) characterization has indicated ellipsoidal and spherical morphologies for both l-PPA-g-PS and c-PPA-g-PS with no significant difference. By comparing the absolute (Mw,abs) and apparent (Mw,app) molar masses, it is found that Mw,abs/Mw,app varies from 1.5 to 3.5 and gradually increases with σ. By measuring gh1/2 (gh1/2 = Rh,graft/Rh,linear), it is found that the two topologies have different compactness of conformation. By following the temperature-dependent interchain aggregation in cyclohexane, it is found that the cyclic backbone feature can suppress the interchain association and be more susceptible to graft density than linear graft polymers. The present study has clearly showed that the cyclic graft topology can potentially display unique structural and conformational properties, which can be attributed to the topological advantages such as more compact conformation and significant isotropic features.
研究领域:
聚合物科学
·
材料科学
·
物理化学
✓ 已验证
DOI
高影响因子
Polymers
·
2018
·Vol. 10
·期 10
·1125
·
IF 2.935
Lulu Liu,Yuanyuan Gao,Juan Zhao,Litong Yuan,Chenglin Li,Zhaojun Liu,Zhaosheng Hou
In the paper, poly(ethylene glycol) (PEG) was grafted on the surface of poly(ester-urethane) (SPEU) film with high grafting density for biomedical purposes. The PEG-surface-grafted SPEU (SPEU-PEG) was prepared by a three-step chemical treatment under mild-reaction conditions. Firstly, the SPEU film surface was treated with 1,6-hexanediisocyanate to introduce -NCO groups on the surface with high density (5.28 × 10−7mol/cm2) by allophanate reaction; subsequently, the -NCO groups attached to SPEU surface were coupled with one of -NH2groups of tris(2-aminoethyl)amine via condensation reaction to immobilize -NH2on the surface; finally, PEG with different molecular weight was grafted on the SPEU surface through Michael addition between terminal C = C bond of monoallyloxy PEG and -NH2group on the film surface. The chemical structure and modified surface were characterized by FT-IR,1H NMR, X-ray photoelectron spectroscopy (XPS), and water contact angle. The SPEU-PEGs displaying much lower water contact angles (23.9–21.8°) than SPEU (80.5°) indicated that the hydrophilic PEG chains improved the surface hydrophilicity significantly. The SPEU-PEG films possessed outstanding mechanical properties with strain at break of 866–884% and ultimate stress of 35.5–36.4 MPa, which were slightly lower than those of parent film, verifying that the chemical treatments had minimum deterioration on the mechanical properties of the substrate. The bovine serum albumin adsorption and platelet adhesion tests revealed that SPEU-PEGs had improved resistance to protein adsorption (3.02–2.78 μg/cm2) and possessed good resistance to platelet adhesion (781–697 per mm2), indicating good surface hemocompatibility. In addition, due to the high grafting density, the molecular weight of surface-grafted PEG had marginal effect on the surface hydrophilicity and hemocompatibility.Keywords:segmented poly(ester-urethane);poly(ethylene glycol);surface grafting;chemical treatment;high grafting density;hemocompatibility
研究领域:
生物医学工程
·
材料科学
·
表面化学
✓ 已验证
DOI
PubMed
高影响因子
POLYMER
·
2022
·
IF 4.432
Yifan Guo,Lianwei Li,Jinxian Yang
In this work, by combing static light scattering (SLS), dynamic light scattering (DLS) and atomic force microscopy (AFM), we have explored how the topological effect influences the intrachain and interchain complexation of polyelectrolytes and divalent ions. First, by a combination of atom transfer radical polymerization (ATRP) and click reaction, two polyacrylic acid (PAA) bottlebrush samples, i.e. PPA 1210 - g -PAA 20 and PPA 2570 - g -PAA 20 , with nearly identical graft density and PAA sidechain length but different backbone lengths, have been prepared. Second, for comparison, a linear sample l -PAA 7710 , with a similar chain size compared to PPA 1210 - g -PAA 20 , has been also prepared. Third, we have systematically investigated the intrachain and interchain complexation between NaPAA topological chains and divalent calcium ions . It is revealed that the intrachain interaction for linear l -PPA 7710 is much stronger than that for bottlebrush samples due to the flexibility feature, while the interchain interaction displays the opposite trend. It is also found that the addition of Ca 2+ results in the change of conformation from loose random coils to dense sphere for l -PAA 7710 , while the overall conformations of PPA 1210 - g -PAA 20 and PPA 2570 - g -PAA 20 almost remain unchange, which can be ascribed to the unique branched structure and enhanced structural rigidity .
研究领域:
高分子化学
·
胶体科学
·
材料科学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）