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351.
Amino‐terminated hyperbranched polysiloxane (AHBSi) with high degree of branching (0.8) is used to improve the compatibilization of polyetherimide (PEI)/allyl bisphenol A modified bismaleimide (BD) blend. The relationship between the compatibility and thermal/thermal‐oxidative stability of the AHBSi/PEI/BD system is intensively investigated. Although PEI has high thermal stability, the PEI/BD blend has poorer thermal stability than BD resin due to the incompatibility. With the addition of AHBSi into the PEI/BD blend, AHBSi chemically connects PEI and BD, leading to the increased compatibility; moreover, interestingly, both thermal and thermo‐oxidative stabilities are significantly improved. Under a N2 atmosphere, the addition of 0.5 wt% of AHBSi increases the initial degradation temperature of the PEI/BD blend from 395°C to 412°C. The thermodegradation kinetics were studied, and results show that the AHBSi/PEI/BD system has much higher activation energy of degradation in both N2 and air atmospheres. The origin behind these interesting results is intensively investigated. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
352.
Daewon Park Veeral Shah Britta M. Rauck Thomas R. Friberg Yadong Wang 《Macromolecular bioscience》2013,13(4):464-469
Reverse thermal gels have numerous biomedical implications, as they undergo physical gelation upon temperature increases and can incorporate biomolecules to promote tissue repair. Such a material is developed for the sustained release of bevacizumab (Avastin), a drug used to treat age‐related macular degeneration. The polymer, poly(ethylene glycol)‐poly(serinol hexamethylene urethane) (ESHU), forms a physical gel when heated to 37 °C and shows good cytocompatibility with ocular cells. ESHU is capable of sustaining bevacizumab release over 17 weeks in vitro, and the release kinetics can be altered by changing the drug dose and the ESHU concentration. These results suggest that ESHU is biologically safe, and suitable for ocular drug delivery.
353.
正态分布的小样本数据的相容性检验理论和方法 总被引:3,自引:0,他引:3
对现有的任意分布的相容性检验理论和方法进行了详细分析和探讨 .指出了现存的一些问题 .并研究了正态分布的小样本容量的相容性检验问题的理论 ,提出了新的检验方法 .检验效果较好 . 相似文献
354.
Compatibility is an important property for energetic materials and their additives such as a casing material or a binder.
If these substances are incompatible an extra risk is introduced in handling and storage of ammunition and explosives. As
part of a co-operation program between the Dutch TNO-PML and the Polish MIAT several compatibility tests are performed and
compared with each other. All tests are performed according to a NATO Standard in which several tests are described which
can be used to determine the compatibility of an energetic material and an additive. These tests were performed on a huge
set of energetic materials e.g. propellants (single and double base), explosives (RDX, PETN, HMX and TNT) and several additives
like Teflon, polypropylene, self-burning case, inhibitors etc. The results of pressure vacuum stability tests, dynamic thermogravimetry
measurements and differential scanning calorimetry tests with several combinations of energetic materials and additives used
during the co-operation program are presented and discussed.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
355.
The improvement of biocompatibility of polyurethanes was investigated.The results demonstrate that the blood compatibility of polyurethanes can be further improved by just simply mixing with the fluorinated phosphatidylcholine poly(carbonate urethane)s(FPCPCUs).The solution blending was done by mixing poly(ether urethane)(PEU)with FPCPCU in different compositions.An increased blood compatibility of the blend films was observed with the increase of FPCPCU content,and when FPCPCU content reached to 40 wt%(... 相似文献
356.
By means of a non‐exact controllability result, we show the necessity of the conditions of compatibility for the exact synchronization by two groups for a coupled system of wave equations with Dirichlet boundary controls. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
357.
By means of a non‐exact controllability result, we show the necessity of the conditions of compatibility for the exact synchronization by two groups for a coupled system of wave equations with Dirichlet boundary controls. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
358.
Nanoparticle Distribution in Three‐Layer Polymer–Nanoparticle Composite Films: Comparison of Experiment and Theory 下载免费PDF全文
Astrid Drechsler Peter Friedel Sebastian Rauch Petra Uhlmann Manfred Stamm Reinhold Rennekamp 《Particle & Particle Systems Characterization》2015,32(1):123-131
The distribution of hydrophobic nanoparticles deposited on a hydrophilic polymer film is investigated by scanning electron microscopy, transmission electron microscopy, and atomic force microscopy before and after spin‐coating a polymer solution on the particle film and drying it at room temperature. Various polymers and solvents are used. To reach equilibrium, all investigated systems are annealed additionally above the glass transition temperature (Tg) of the polymers. The compatibility of the interacting components is estimated by calculating their surface energy, solubility, and mutual interaction parameters. The experimental results show a redistribution of the particles on both interfaces of the polymer film. This corresponds to the calculated immiscibility of particles and polymers. The distribution of the nanoparticles at the interfaces is related mainly to the vapor pressure of the solvent, that is, kinetic effects during spin‐coating. Only minor contributions result from surface energy, solubility, and interaction parameters. 相似文献
359.
360.
C. Lexcellent A. Vivet C. Bouvet S. Calloch P. Blanc 《Journal of the mechanics and physics of solids》2002,50(12):2717-2735
Biaxial proportional loading such as tension (compression)–internal pressure and bi-compression tests are performed on a Cu-Zn-Al and Cu-Al-Be shape memory polycrystals. These tests lead to the experimental determination of the initial surface of phase transformation (austenite→martensite) in the principal stress space (σ1,σ2). A first “micro–macro” modeling is performed as follows. Lattice measurements of the cubic austenite and the monoclinic martensite cells are used to determine the “nature” of the phase transformation, i.e. an exact interface between the parent phase and an untwinned martensite variant. The yield surface is obtained by a simple (Sachs constant stress) averaging procedure assuming random texture. A second modeling, performed in the context of the thermodynamics of irreversible processes, consists of a phenomenological approach at the scale of the polycrystal. These two models fit the experimental phase transformation surface well. 相似文献