نتایج جستجو برای: polymer thin film

تعداد نتایج: 272367  

2014
Ali Mesbah Ashlee N. Ford Versypt Xiaoxiang Zhu Richard D. Braatz

This paper considers the model-based control of composition and thickness for a thin-film drying process used in the continuous manufacturing of pharmaceutical tablets. In this nonlinear distributed dynamical system, a drug formulation solution is coated onto a moving surface and then dried to form thin films of approximately 250 μm in thickness. A dynamic optimizer is designed that employs a f...

Journal: :international journal of nano dimension 0
s. habibzare department of chemical engineering, north tehran branch, islamic azad university, tehran, iran. m. asghari separation processes research group (sprg), department of engineering, university of kashan, kashan, iran. a. djirsarai energy research institute, university of kashan, ghotb-e-ravandi ave., kashan, iran.

the performances of two-phase polymer-liquid pebax®/polyethylene glycol (peg) and three-phase polymer-liquid-solid pebax®/peg/mwnt thin film composite membranes for co2 and ch4 permeation were studied. the effect of temperature and mwnt/pebax® ratio on single gas (co2 and ch4) permeability was investigated. the permeation of both gases was measured at different temperatures from 303 to 323 ˚k. ...

Journal: :Nature communications 2014
Paul Z Hanakata Jack F Douglas Francis W Starr

Thin polymer films are ubiquitous in manufacturing and medical applications, and there has been intense interest in how film thickness and substrate interactions influence film dynamics. It is appreciated that a polymer-air interfacial layer with enhanced mobility plays an important role in the observed changes and recent studies suggest that the length scale ξ of this interfacial layer is rela...

2008
Nanshu Lu Xi Wang Zhigang Suo Joost Vlassak

In a previous paper, we have demonstrated that a microcrystalline copper film well bonded to a polymer substrate can be stretched beyond 50% without cracking. The film eventually fails through the coevolution of necking and debonding from the substrate. Here we report much lower strains to failure (approximately 10%) for polymer-supported nanocrystalline metal films, the microstructure of which...

2017
Miriam Carlberg Florent Pourcin Olivier Margeat Judikaël Le Rouzo Gérard Berginc Rose-Marie Sauvage Jörg Ackermann Ludovic Escoubas

This work is focused on the study of the optical properties of silver nanostructures embedded in a polymer host matrix. The introduction of silver nanostructures in polymer thin films is assumed to result in layers having adaptable optical properties. Thin film layers with inclusions of differently shaped nanoparticles, such as nanospheres and nanoprisms, and of different sizes, are optically c...

Mohammad Mehdi Tehranchi, Seyed Mohammad Hosein Khalkhali, Seyedeh Mehri Hamidi,

We examine the photo-assisted polarization loop in a BiFeO3 thin film under UV light illumination. BiFeO3 thin film prepared by pulsed laser deposition method onto the BaTiO3 thin film and the polarization behavior has been measured under poling voltage. Our results show the engineered polarization due to controllable schottky barrier under inverse poling voltage. This control on schottky barri...

Journal: :The European physical journal. E, Soft matter 2012
Tao Wang Andrew J Pearson Alan D F Dunbar Paul A Staniec Darren C Watters David Coles Hunan Yi Ahmed Iraqi David G Lidzey Richard A L Jones

We report surface and interface effects in dynamics and chain conformation in the thin film of conjugated polymer PCDTBT. To probe dynamic anomalies, we measure the glass transition temperature (T(g)) of PCDTBT films as a function of thickness, and find that there is a significant depression in T(g) for films less than 100 nm thick; a result qualitatively similar to that observed in many other ...

Journal: :Science 1992
H W Hu S Granick

The frequency-dependent shear response of an ultrathin polymer melt (polyphenylmethylsiloxane) confined between adsorbing surfaces (parallel plates of mica) is described. The sinusoidal deformations were sufficiently small to give linear response, implying that measurement did not perturb the film structure. A remarkable transition was observed with decreasing thickness. When the film thickness...

Journal: :The journal of physical chemistry. B 2008
Miriam A Freedman James S Becker S J Sibener

We have investigated the surface vibrational dynamics at the polymer-vacuum interface of atactic poly(methyl methacrylate) thin films supported on SiO(x)/Si(100) as a function of film thickness and molecular weight. The highly surface-sensitive and nondestructive technique of inelastic helium atom scattering probes the vibrational dynamics at the true polymer-vacuum interface due to the lack of...

2008
P. G. de Gennes

When a glassy polymer film is formed by evaporation, the region near the free surface is polymer rich and becomes glassy first, as noticed long ago by Scriven et al. We discuss the thickness of this ”crust” and the time interval where it is present -before freezing of the whole film. We argue that the crust is under mechanical tension, and should form some cracks. This may be the source of the ...

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