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1.
Viscoelastic properties of poly(ε‐caprolactone)/clay nanocomposites in solid and in melt state 下载免费PDF全文
Viscoelastic properties in solid and in melt state of poly(ε‐caprolactone), PCL, nanocomposites with organomodified clays (Cloisite30B and Cloisite15A) are thoroughly investigated. Although WAXD is insensitive to the difference in the nanocomposites structure, the melt rheology reveals pronounced differences between the two series. Melt yield stress values, obtained from fittings by the Carreau–Yasuda model, are used as a measure of partial exfoliation of the clay. Temperature dependence of the shift factors, used for time–temperature superposition of the modulus curves, yields similar values of the flow activation energies for all the samples. Temperature dependences of the dynamic modulus and loss factor of solid nanocomposites were correlated to the structural differences deduced from the melt rheology. The increase in the storage modulus is compared to the theoretical predictions from the Halpin–Tsai model. The effective aspect ratio obtained from this comparison agrees reasonably with the value estimated from the melt rheology. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 42896. 相似文献
2.
Efficient wound odor removal by β‐cyclodextrin functionalized poly (ε‐caprolactone) nanofibers 下载免费PDF全文
Polymer‐cyclodextrin (CD) composite nanofibers, by virtue of the hollow cavities and abundant hydroxyl groups present in CDs, have tremendous potential in a variety of biomedical applications. However, in most cases, especially in aliphatic polyesters, polymer chains thread readily into CD cavities, therefore its potential has not yet been fully realized. Herein, we report the formation of poly(ε‐caprolactone) (PCL)/β‐CD functional nanofibers by electrospinning their mixture from chloroform/N,N‐dimethylformamide (60 : 40). The fiber diameters of the neat PCL and β‐CD functionalized fibers were measured from the images obtained from a scanning electron microscope and were found to be about 500 nm. The efficiency of wound odor absorbance by these composite fibers was studied using a simulated wound odor solution, consisting of butyric and propionic acids in ethanol. Immersion tests indicated that even under less than ideal test conditions, the nanofibers containing β‐CDs were very efficient in masking the odor. The odor masking capability of the β‐CD functionalized PCL nanofibers were further confirmed by thermogravimetric analyses and GC observations, with the former method showing unique degradation patterns. The PCL/β‐CD nanocomposites, by virtue of having their β‐CD cavities free and unthreaded by PCL, could potentially be an ideal substrate for removing wound odors through formation of inclusion compounds with odorants, while providing an ideal environment for the wound to heal. These results suggest tailoring polymer‐CD nanostructures for specific applications in wound odor absorbance, surface grafting of chemical moieties, and vehicles for drug delivery, as examples. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42782. 相似文献
3.
Morphological,thermal, and mechanical properties of poly(ε‐caprolactone)/poly(ε‐caprolactone)‐grafted‐cellulose nanocrystals mats produced by electrospinning 下载免费PDF全文
Caroline F. Bellani Eric Pollet Anne Hebraud Fabiano V. Pereira Guy Schlatter Luc Avérous Rosario E. S. Bretas Marcia C. Branciforti 《应用聚合物科学杂志》2016,133(21)
Electrospun nanocomposites of poly(ε‐caprolactone) (PCL) incorporated with PCL‐grafted cellulose nanocrystals (PCL‐g‐CNC) were produced. PCL chains were grafted from cellulose nanocrystals (CNC) surface by ring‐opening polymerization. Grafting was confirmed by infrared spectroscopy (FTIR) and thermogravimetric analyses (TGA). The resulting PCL‐g‐CNC were then incorporated into a PCL matrix at various loadings. Homogeneous nanofibers with average diameter decreasing with the addition of PCL‐g‐CNC were observed by scanning electron microscopy (SEM). PCL‐g‐CNC domains incorporated into the PCL matrix were visualized by transmission electron microscopy (TEM). Thermal and mechanical properties of the mats were analyzed by differential scanning calorimetry (DSC), TGA and dynamic mechanical analysis (DMA). The addition of PCL‐g‐CNC into the PCL matrix caused changes in the thermal behavior and crystallinity of the electrospun fibers. Significant improvements in Young's modulus and in strain at break with increasing PCL‐g‐CNC loadings were found. These results highlighted the great potential of cellulose nanocrystals as a reinforcement phase in electrospun PCL mats, which can be used as biomedical materials. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43445. 相似文献
4.
Madhab Prasad Bajgai Santosh Aryal Daman Chandra Parajuli Myung‐Seob Khil Duck Rae Lee Hak Yong Kim 《应用聚合物科学杂志》2009,111(3):1540-1548
Brush copolymers composed of methoxy poly(ethylene glycol) (MPEG) and poly(ε‐caprolactone) (PCL) have been synthesized by the ring‐opening polymerization of ε‐caprolactone initiated by hydroxyl function of thermally esterified MPEG‐citrate in presence of stannous octoate. Citric acid (CA) acts as spacer between brush‐like MPEG and the long chain of PCL. Existence of hydrophobic domains as cores of the micelles were characterized by 1H NMR spectroscopy and further confirmed with fluorescence technique using pyrene as a probe. Critical micelle concentration (CMC) of the synthesized copolymer decreased from 0.019 to 0.0031 mg/mL on increasing the fraction of PCL. Along with the physicochemical study, the brush copolymers were explored for the preparation of nanoparticles by nanoprecipitation technique. The morphology and geometry of micelles were investigated by using DLS, AFM, and TEM. Hydrodyanamic dimensions of micelles were around 118 and 178 nm with the core size of 8–10 nm, which further aggregated to form secondary micelle of 60–90 nm. Such assembled polymeric micelles with its flexible dendritic MPEG corona could hold a promise for the immobilization (encapsulation) of hydrophobic drugs and subsequently promote sustained release so that it can be a good vehicle for anti‐cancer drug deliverance. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009 相似文献
5.
Mahadevappa Y Kariduraganavar Frederick J Davis Geoffrey R Mitchell Robert H Olley 《Polymer International》2010,59(6):827-835
Electrospinning is a route to polymer fibres with diameters considerably smaller than available from most fibre‐producing techniques. We explore the use of a low molecular weight compound as an effective control additive during the electrospinning of poly(ε‐caprolactone). This approach extends the control variables for the electrospinning of nanoscale fibres from the more usual ones such as the polymer molecular weight, solvent and concentration. We show that through the use of dual solvent systems, we can alter the impact of the additive on the electrospinning process so that finer as well as thicker fibres can be prepared under otherwise identical conditions. As well as the size of the fibres and the number of beads, the use of the additive allows us to alter the level of crystallinity as well as the level of preferred orientation of the poly(ε‐caprolactone) crystals. This approach, involving the use of a dual solvent and a low molar mass compound, offers considerable potential for application to other polymer systems. Copyright © 2010 Society of Chemical Industry 相似文献
6.
Biodegradable polyester blends were prepared from poly(L ‐lactic acid) (PLLA) and poly(ε‐caprolactone) (PCL) (50/50) by melt‐blending, and the effects of processing conditions (shear rate, time, and strain) of melt‐blending on proteinase‐K‐ and lipase‐catalyzed enzymatic degradability were investigated using gravimetry, differential scanning calorimetry, and scanning electron microscopy. The proteinase‐K‐catalyzed degradation rate of the blend films increased and leveled off with increasing the shear rate, time, or strain for melt‐blending, except for the shortest shear time of 60 s. The optimal processing conditions of melt‐blending giving the maximum rate of lipase‐catalyzed degradation were 9.6 × 102 s?1 and 180 s, whereas a deviation from these conditions caused a reduction in lipase‐catalyzed enzymatic degradation rate. At the highest shear rate of 2.2 × 103 s?1, PCL‐rich phase was continuous in the blend films, irrespective of the shear time (or shear strain), whereas PLLA‐rich phase changed from dispersed to continuous by increasing the shear time (or shear strain). This study revealed that the biodegradability of PLLA/PCL blend materials can be manipulated by altering the processing conditions of melt‐blending (shear rate, time, or strain) or the sizes and morphology of PLLA‐rich and PCL‐rich domains. The method reported in the present study can be utilized for controlling the biodegradability of other biodegradable polyester blends. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 831–841, 2007 相似文献
7.
A series of poly(?‐caprolactone) (PCL)/graphite oxide (GO) composites were synthesized through the ring‐opening polymerization of ?‐caprolactone with GO as an initiator. The crystallization behavior of the PCL–GO composites and the effects of the PCL–GO composites as nucleation agents on the crystallization behavior of PCL were also studied. The introduction of GO as PCL–GO composites shortened the crystallization half‐time for both the isothermal crystallization and nonisothermal crystallization of PCL, and this clearly indicated that GO in the PCL–GO composites had a great nucleating effect on the crystallization of pure PCL. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007 相似文献
8.
Poly(?‐caprolactone) was crosslinked by γ radiation in the presence of triallyl isocyanurate. The influence of γ‐radiation crosslinking on the thermal and mechanical properties of poly(?‐caprolactone)/triallyl isocyanurate was investigated. Differential scanning calorimetry analyses showed differences between the first and second scans. Dynamic mechanical analysis showed an increase in the glass‐transition temperature as a result of the radiation crosslinking of poly(?‐caprolactone). Thermogravimetric analysis showed that γ‐radiation crosslinking slightly improved the thermal stability of poly(?‐caprolactone). The γ radiation also strongly influenced the mechanical properties. At room temperature, crosslinking by radiation did not have a significant influence on the Young's modulus and yield stress of poly(?‐caprolactone). However, the tensile strength at break and the elongation at break generally decreased with an increase in the crosslinking level. When the temperature was increased above the melting point, the tensile strength at break, elongation at break, and Young's modulus of poly(?‐caprolactone) were also reduced with an increase in the crosslinking level. The yield stress disappeared as a result of the disappearance of the crystallites. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 2676–2681, 2007 相似文献
9.
Crystallization and melting behavior of poly(ε‐caprolactone‐co‐δ‐valerolactone) and poly(ε‐caprolactone‐co‐L‐lactide) copolymers with novel chain microstructures 下载免费PDF全文
Nuclear magnetic resonance spectroscopy (NMR) characterization of the statistical copolymers of this study showed that the poly(ε‐caprolactone‐co‐L‐lactide)s, with ε‐caprolactone (ε‐CL) molar contents ranging from 70 to 94% and ε‐CL average sequence length (lCL) between 2.20–9.52, and the poly(ε‐caprolactone‐co‐δ‐valerolactone)s, with 60 to 85% of ε‐CL and lCL between 2.65–6.08, present semi‐alternating (R→2) and random (R~1) distribution of sequences, respectively. These syntheses were carried out with the aim of reducing the crystallinity of poly(ε‐caprolactone) (PCL), needed to provide mechanical strength to the material but also responsible for its slow degradation rate. However, this was not achieved in the case of the ε‐caprolactone‐co‐δ‐valerolactone (ε‐CL‐co‐δ‐VAL). Non‐isothermal cooling treatments at different rates and isothermal crystallizations (at 5, 10, 21 and 37°C) were conducted by differential scanning calorimetry (DSC), and demonstrated that ε‐CL copolymers containing δ‐valerolactone (δ‐VAL) exhibited a larger crystallization capability than those of L‐lactide (L‐LA) and also arranged into crystalline structures over shorter times. The crystallization enthalpies of the ε‐CL‐co‐δ‐VAL copolymers during the cooling treatments and their heat of fusion (ΔHm) at the different isothermal temperatures were very large (i.e. ΔHc > 53 Jg?1) and in some cases, unrelated to the copolymer composition. In some compositions, such as the 60 : 40, Wide Angle X‐ray Scattering (WAXS) proved that that these two lactones undergo isomorphism and co‐crystallize in a single cell. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42534. 相似文献
10.
Biodegradable polymers, blends, and composites are often investigated during tissue engineering studies, but their fracture properties, which are important mechanical engineering characteristics, are often disregarded or wrongly treated. In this study, essential work of fracture tests were performed on calcium carbonate filled poly(ε‐caprolactone), a very ductile polymer, to determine the effects of different filler shapes (calcite spheres and aragonite whiskers), sizes, and contents on the fracture parameters. Increasing the filler content caused stability problems during crack propagation, and this influenced the self‐similarity of the load–displacement response and resulted in the yielding point being missed. Moreover, the yielding‐related essential work of fracture and the energy dissipating during yielding were found to be almost independent of the filler content and thus could be indicators of matrix–filler adhesion. A shape effect of aragonite whiskers appeared during stable crack propagation; the motion of the particles and the friction on their surface slightly increased the dissipated energy quantum and resulted in a more oriented molecular structure. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 相似文献
11.
Yoon Sung Nam Kil Joong Kim Hyung Seok Kang Tae Gwan Park Sang‐Hoon Han Ih‐Seop Chang 《应用聚合物科学杂志》2003,89(6):1631-1637
All‐trans‐retinoic acid (RA) was chemically conjugated to biodegradable poly(ε‐caprolactone) (PCL10; number‐average Mw ≈ 1250) via an ester linkage. The conjugation was carried out using N,N‐dicyclohexylcarbodiimide and 4‐dimethyl aminopyridine as a coupling agent. The molar ratio of the drug to the polymer was 1.11 as determined by 1H‐NMR analysis. DSC and WAXD results showed that the formation of crystalline structures of RA was effectively suppressed by conjugation with PCL. The RA–PCL conjugates were formulated into nanoparticles by a spontaneous phase‐inversion technique. Morphological characteristics of the resultant nanoparticles and drug‐loading efficiencies were compared with those of free RA‐loaded nanoparticles. The drug‐loading efficiency of RA–PCL conjugates was almost 100%, while that of free RA was only ~12%. The majority of unconjugated RA was found to form undesirable free‐drug crystals out of nanoparticles, as observed by TEM analysis. This study demonstrates that the conjugation approach of RA to PCL can be an effective means to immobilize and encapsulate RA within nanoparticles for pharmaceutical applications. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 1631–1637, 2003 相似文献
12.
Poly(l ‐lactide‐co‐ε‐caprolactone‐diOH) (PCLA) with (ABA)n type is synthesized using poly(lactic acid) (PLA) and poly(ε‐caprolactone) di‐OH (PCL‐diOH) via chain extending method. FT‐IR, 1H‐NMR, and GPC data demonstrate that PLA and PCL‐diOH have reacted completely. The product is electrospun into ultrafine fibers subsequently. The optimum electrospinning parameters obtain from an orthogonal experiment are a solvent ratio (DMF/DCM) of 5/5, a polymer concentration of 28 wt %, a collector distance of 20 cm and a voltage of 18 kV. As a result, the average diameter of fibers is 0.77 µm and the uniformity is above 80%. Via range analysis, it is found that the order of the influence on diameter is solvent ratio, applied voltage, collector distance, and polymer concentration, successively. Single effect of the four governing factors on diameter and morphology is also experimentally investigated. This may provide clues for obtaining fibers with various structures by controlling the parameters. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 3600–3610, 2013 相似文献
13.
The condensation reaction product of poly(lactic acid) (PLA) and a hydroxyl‐terminated four‐armed poly(ε‐caprolactone) (PCL) was studied by size‐exclusion chromatography, DSC, and NMR. The use of both L ‐lactic acid (LLA) and rac‐lactic acid (rac‐LA) was studied and the use of two different catalysts, stannous 2‐ethylhexanoate [Sn(Oct)2] and ferrous acetate [Fe(OAc)2], was also investigated. The thermal stability and adhesive properties were also measured for the different formulations. The characterization results suggested the formation of a blend of PLA and a block‐copolyester of PLA and PCL. The results further indicated partial miscibility in the amorphous phase of the blend showing only one glass‐transition temperature in most cases, although no randomized structures could be detected in the block‐copolymers. The polymerization in the Fe(OAc)2‐catalyzed experiments proceeded slower than in the Sn(Oct)2‐catalyzed experiments. The discoloring of the polymer was minor when Fe(OAc)2 was used as catalyst, but significant when Sn(Oct)2 was used. The ferrous catalyst also caused a slower thermal degradation. Differences in the morphology and in the adhesive properties could be related to the stereochemistry of the poly(lactic acid). © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 196–204, 2004 相似文献
14.
The effect of graphite oxide (GO) as the enforcing filler on the properties of poly(?‐caprolactone) (PCL) was investigated in this study. Through the introduction of GO, the Young's modulus of PCL was increased from 340 to 1000 MPa, and the tensile strength of PCL was increased from 15 to 26 MPa. Furthermore, the interlayer distance of GO (0.6 nm) was found to expand to 1.1 nm in the PCL/GO composite, which indicated the intercalation of the PCL chain into the GO layers. Because of this intercalation structure of the PCL/GO composite, GO showed a higher reinforcing effect than graphite on the mechanical properties of PCL. The intercalation should have enabled much effective load transfer in the PCL/GO composites. Moreover, GO showed a nucleating effect toward the crystallization of PCL, as the nonisothermal crystallization peak temperature shifted from 25°C for pure PCL to about 34°C for the PCL/GO composites. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献
15.
Preparation and characterization of Rana chensinensis skin extract/poly(ε‐caprolactone) electrospun membranes as antibacterial fibrous mats 下载免费PDF全文
Mei Zhang Wen‐Yu Xu Jia‐Mian Wang Jia‐Shuang Luan He‐Nan Dong Yu‐Jing Zhang Xue‐Qi Li Da‐Hui Sun 《应用聚合物科学杂志》2015,132(23)
In this study, membranes composed of Rana chensinensis skin extracts (RCSEs) and poly(ε‐caprolactone) (PCL) were fabricated by an electrospinning technique. The RCSEs were prepared by the extraction of R. chensinensis skin with acetic acid solution, and the electrospun membranes were prepared by the mixture of RCSEs and PCL in 1,1,1,3,3,3‐hexafluoro‐2‐propanol before electrospinning. The membranes were characterized by scanning electron microscopy and Fourier transform infrared spectroscopy and were subjected to mechanical tests (tensile and nanoindentation) and antibacterial evaluation. The results indicate that the surface roughness of the fibers clearly decreased with the increase in the amount of PCL in the membranes. The mechanical test indicated that PCL played a dominant role in the mechanical strength of the RCSE/PCL electrospun membranes. As a potential bactericidal packaging material for practical applications, the antibacterial activity results indicate that the membranes had antibacterial effects against Staphylococcus aureus and Escherichia coli. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42030. 相似文献
16.
Abdoulkader Ali Mohamed Slim Salhi Souhir Abid Rachid El Gharbi Alain Fradet 《应用聚合物科学杂志》2016,133(46)
Glycine‐ɛ‐caprolactone‐based and α‐alanine‐ɛ‐caprolactone‐based polyesteramides with a strong tendency to form alternating sequences (degree of randomness = 1.64 and 1.31) were synthesized by melt polycondensation of intermediate hydroxy‐ and ethyl ester‐terminated amides. These intermediates were synthesized by the reaction of equimolar amounts of ɛ‐caprolactone and glycine or L‐α‐alanine ethyl esters in mild conditions. The structure and microstructure of these polyesteramides are discussed on the basis of an in‐depth nuclear magnetic resonance study. Both polyesteramides are semi‐crystalline, but the glycine‐based one presents the highest melting enthalpy. This polyesteramide also exhibits higher Young's modulus and stress at break than its α‐ and β‐alanine counterparts. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 44220. 相似文献
17.
Environmentally friendly organocatalytic synthesis of aliphatic polyesters was studied. The catalysis investigated is novel, and lends itself well to the potential production of valuable biodegradable products. The reactions were based on an organic acids‐catalyzed ring‐opening polymerization of ε‐caprolactone with fatty acid derivatives as the initiator and were performed in the absence of solvents. The chemical structures of the functionalized polymers were confirmed by 1H and 13C‐NMR spectra. Polymers with different molecular weights, in the range 10,900–15,200 were obtained in the presence of fumaric acid as catalyst. The thermal properties of the functionalized PCLs were determined by modulated differential scanning calorimetry and thermogravimetric analysis. The MDSC results verified that the crystallinity and the melting point of the lipid‐functionalized polymers were lower than that of the unfunctionalized poly(ε‐caprolactone). The hydrolytic degradation of the functionalized polymer was also investigated. The result shows the degradation rate was affected by the presence of oleic acid derivatives in the polymer molecule. The lipid‐functionalized polymers synthesized by the metal‐free polymerization systems seem to be suitable biodegradable polyesters for use in biomedical and pharmacological applications. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 相似文献
18.
Thermally exfoliated graphene oxide reinforced fluorinated pentablock poly(l‐lactide‐co‐ε‐caprolactone) electrospun scaffolds: Insight into antimicrobial activity and biodegradation 下载免费PDF全文
Burcu Saner Okan Azucena Marset Jamal Seyyed Monfared Zanjani Pınar Akkus Sut Ozlem Sen Mustafa Çulha Yusuf Menceloglu 《应用聚合物科学杂志》2016,133(22)
Three‐dimensional fluorinated pentablock poly(l ‐lactide‐co‐ε‐caprolactone)‐based scaffolds were successfully produced by the incorporation of thermally exfoliated graphene oxide (TEGO) as an antimicrobial agent with an electrospinning technique. In a ring‐opening polymerization, the fluorinated groups in the middle of polymer backbone were attached with a perfluorinated reactive stabilizer having oxygen‐carrying ability. The fiber diameter and its morphologies were optimized through changes in TEGO amount, voltage, polymer concentration, and solvent type to obtain an ideal scaffold structure. Instead of the widely used graphene oxide synthesized by Hummer's method, TEGO sheets having a low amount of oxygen produced by thermal expansion were integrated into the fiber structure to investigate the effect of the oxygen functional groups of TEGO sheets on the degradation and antimicrobial activity of the scaffolds. There was no antimicrobial activity in TEGO‐reinforced scaffolds in the in vitro tests in contrast to the literature. This study confirmed that a low number of oxygen functional groups on the surface of TEGO restricted the antimicrobial activity of the fabricated composite scaffolds. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43490. 相似文献
19.
Application of the dry‐spinning method to produce poly(ε‐caprolactone) fibers containing bovine serum albumin laden gelatin nanoparticles 下载免费PDF全文
Bahareh Azimi Parviz Nourpanah Mohammad Rabiee Shahram Arbab Maria Grazia Cascone Andrea Baldassare Luigi Lazzeri 《应用聚合物科学杂志》2016,133(48)
We designed and manufactured a polymeric system with combined hydrophilic–hydrophobic properties by loading gelatin nanoparticles (GNPs) containing bovine serum albumin (BSA) into poly(ε‐caprolactone) (PCL) fibers. Our ultimate goal was to create a device capable of carrying and releasing protein drugs. Such a system could find several biomedical applications, such as those in controlled release systems, surgical sutures, and bioactive scaffolds for tissue engineering. A two‐step desolvation method was used to produce GNPs, whereas PCL fibers were produced by a dry‐spinning method. The morphological, mechanical, and thermal properties of the produced system were investigated, and the distribution of nanoparticles both inside and on the surface of the fibers was examined. The effect of the particles on the biodegradability of the fibers was also evaluated. In vitro preliminary tests were performed to study the release of BSA from nanoparticle‐laden fibers and to compare this with its release from free nanoparticles. Our results indicate that the distribution of particles inside the fibers was quite homogeneous and only a few of them were present on the surface. The presence of the particles in the fibers did not affect the thermal properties of the PCL polymer matrix, although it created voids that affected the degradation characteristics so the PCL fibers favored faster erosion compared to the plain fibers. Preliminary results indicate that the release from GNP‐laden fibers occurred much more slowly compared to that in the free GNPs. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 44233. 相似文献
20.
Sheng Meng Wei Zhong Laisheng L. Chou Qihong Wang Zongjun Liu Qiangguo Du 《应用聚合物科学杂志》2007,103(2):989-997
In this study, the synthesis, characterization, and properties of a novel biodegradable polymer with improved hemocompatibility were introduced. It was synthesized by end‐capping poly‐ε‐caprolactone (PCL) with phosphorylcholine (PC) groups. The polyester backbone provided the mechanical stability and biodegradability, while the PC‐end groups improved its hemocompatibility. The obtained polymer was characterized using 1H NMR, 31P NMR, FTIR, and GPC, its crystallization behavior was studied by DSC. Compared with original PCL, the resulting polymer (PC‐PCL) showed a lower crystallization capability and a faster degradation rate in PBS. The degradation rate of the polymer blends of PCL/PC‐PCL increased with increasing PC‐PCL content. The results of water contact angle measurements revealed a more hydrophilic surface property of PC‐PCL than neat PCL. The hemocompatibility of PC‐PCL was estimated using rabbit platelet‐rich plasma, a better resistance to platelet adhesion and activation was observed. During the human blood plasma contacting process, PC‐PCL showed a prolonged activated partial thromboplastin time over neat PCL. Material–cell interaction was evaluated with human umbilical vein endothelial cell, the result indicated that PC‐PCL may to some extent have an antihyperplasia property, compared with neat PCL. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 989–997, 2007 相似文献