In the context of conjugated polymers, especially those of the poly (phenylenevinylene) (PPV) family, which are promising candidates as emission material in light emitting devices such as LEDs, field effect transistors and photovoltaic devices, we have, in the present study, prepared MEH-PPV [Poly [2- methoxy-5-(2’-ethyl-hexyloxy)-1,4-phenylen-evinylene] of low molecular weight and low polydisp...

Thin films of polystyrene on silicon substrate were investigated for thickness-dependent interface properties. To better understand the desirable electrical, mechanical, and optical properties of a polymer thin film, the interfacial structures must be first understood. Using x-ray reflectivity, data from polystyrene-air and polystyrene-silicon interfaces were collected and correlated with a the...

poly n-isopropylacrylamide was successfully grafted onto a polystyrene cell culture dish by gamma ray. in this study, the effect of a radiation dose (radiation absorbed dosages of 10, 20, 30, 40 kgy) under appropriate temperature and grafting conditions was investigated. the ftir analysis showed the existence of the graft pnipaam on the substrate. the optimal value of the dose for grafting was ...

A triblock terpolymer, polystyrene-block-polybutadiene-block-poly(methyl methacrylate) (SBM), formed a double-helical nanoscale structure, composed of polybutadiene (PB) helical microdomains around hexagonally packed polystyrene (PS) cores in a poly(methyl methacrylate) matrix. The orientation of double-helical morphologies at various film thicknesses were studied using transmission electron mi...

We present a new wrinkling-based measurement technique for quantifying the viscoelastic properties of confined polymer thin films. This approach utilizes real-time laser-light scattering to observe the kinetics of thermally-induced surface wrinkling, which evolves isothermally as a function of annealing time. Specifically, wrinkling is induced by applying a thermal stress to a polystyrene film ...

Acoustic wave sensors have been widely used for detection of various chemical and biological species in liquid media. We report an improved binding of Protein A and IgG molecules on QCM biosensors by modifying the gold surface of the quartz crystal with a 35 nm polystyrene film followed by an acidic treatment. The frequency shifts due to the binding of the Protein A and IgG were 220 and 282 Hz,...

One way to produce high order in a block copolymer thin film is by solution casting a thin film and slowly evaporating the solvent in a sealed vessel. Such a solvent-annealing process is a versatile method to produce a highly ordered thin film of a block copolymer. However, the ordered structure of the film degrades over time when stored under ambient conditions. Remarkably, this aging process ...

The energy dependence of radiographic film can introduce dosimetric errors when evaluating photon beams. The variation of the film response, which is attributed to the changing photon spectrum with depth and field size, has been the subject of numerous publications in recent years. However, these data show large unexplained differences in the magnitude of this variation among independent studie...

Excellent dispersion of functionalized graphene (FG) sheets in polystyrene was achieved relying on the reaction of "living" poly(glycidyl phenyl ether) chains onto graphene sheets. The physical aging of polystyrene was substantially accelerated by the presence of FG sheets at low filler content, retaining film transparency and increasing the electrical conductivity.

Using a biomedical sensor setup RIfS we have investigated the kinetic behavior of human albumin (Alb), human fibrinogen (Fib), and human immunoglobulin G (IgG) adsorbed onto surfaces of chitosan. Polystyrene (PS) was used as the control material in this study. The optical thickness of three kinds of proteins measured by RIfS was related to their molecular dimensions and potential orientations o...