Polymers and Other Materials

Akhremitchev et al. presented a set-up based on the same principle, namely 1R s-SNOM with a side-illuminated AFM tip, and employed it to characterize nano-structured polymer blends that were used as minimally adhesive surface coatings to prevent biofouHng [57, 58]. Raschke ct al. used sharp Au-coated, forward-pointing ( nose-type ) AFM probes with a radius of 10-15 nm, and obtained fixed- 

Figu re 15.8 s-SNOM analysis of polystyrene (PS) in a PMMA matrix, (a) Calculated s-SNOM amplitude spectra of PMMA (solid line) and of PS (dashed line) (b) Topography (left) and IR amplitude (right) s-SNOM images of a 70nm-thick polymer blend film 

The IR s-SNOM approach can also be applied to other materials. For example, Keilmann and coworkers have shown examples ranging from SiC partially covered with Au [33] to metal/Si/polymer three-component samples [60] and even subsurface imaging in such three-component systems [61]. 

An approach to full spectroscopic near-field imaging in the IR range was presented by Michaels et al. [62], whose illumination-mode a-SNOM set-up was based on a Ti sapphire-pumped optical parametric amplifier (OPA) coupled into a tapered fluoride glass optical fiber. The OPA system provides tunable broadband IR radiation with output powers in the miUi Watt range. After passing the thin film sample, the transmitted fight is collected by a Cap2 lens and coupled into a monochromator with a detector array. Broadband illumination with a bandwidth 

As the size of the aperture is defined by the IR absorption of water, the lateral resolution clearly depends on the wavelength, with the best results obtained in regions of the spectrum where water absorbs strongly. The authors reported that, with such an approach, a resolution in the range of 10 nm or X/600 is within reach. 

---

L. C. E. Stmik, PhjsicalAging in Amorphous Polymers and Other Materials, Elsevier, Amsterdam, the Netherlands, 1978. 

D. R. Lloyd, T. C. Ward, H. Schrieber, eds.. Inverse Gas Chromatographj Charactericyation of Polymers and Other Materials, American Chemical Society, Washington, D.C., 1989. 

Amorphous stereotactic polymers can crystallise, in which condition neighbouring chains are parallel. Because of the unavoidable chain entanglement in the amorphous state, only modest alignment of amorphous polymer chains is usually feasible, and moreover complete crystallisation is impossible under most circumstances, and thus many polymers are semi-crystalline. It is this feature, semicrystallinity, which distinguished polymers most sharply from other kinds of materials. Crystallisation can be from solution or from the melt, to form spherulites, or alternatively (as in a rubber or in high-strength fibres) it can be induced by mechanical means. This last is another crucial difference between polymers and other materials. Unit cells in crystals are much smaller than polymer chain lengths, which leads to a unique structural feature which is further discussed below. 

Struik LCE (1978) Physical aging in amorphous polymers and other materials, Elsevier, Amsterdam... 

Taniguchi and Ninomiya [273] and Ninomiya et al. [274] have reviewed TXRF as an inherently surface-sensitive, nondestructive and cost-saving method in the analysis of trace elements and other microcomponents in polymers and other materials. An overview of sources, samples and detectors for TXRF is available [275]. 

C.N.R. Rao, H.S.S. Ramakrishna Matte, and Urmimala Maitra 6 Graphene and its hybrids with inorganic nanoparticles, polymers and other materials... 

Graphene and its hybrids with inorganic nanoparticles, polymers and other materials... 

Struik, L.C.E. Physical Aging in Amorphous Polymers and Other Materials Elseyier Amsterdam 1978. 

For conductive polymers, and other materials, conductivity is defined by Ohm s law which says... 

Positron annihilation lifetime spectroscopy (PALS) provides a method for studying changes in free volume and defect concentration in polymers and other materials [1,2]. A positron can either annihilate as a free positron with an electron in the material or capture an electron from the material and form a bound state, called a positronium atom. Pnra-positroniums (p-Ps), in which the spins of the positron and the electron are anti-parallel, have a mean lifetime of 0.125 ns. Ortho-positroniums (o-Ps), in which the spins of the two particles are parallel, have a mean lifteime of 142 ns in vacuum. In polymers find other condensed matter, the lifetime of o-Ps is shortened to 1-5 ns because of pick-off of the positron by electrons of antiparallel spin in the surrounding medium. 

The fundamental difference between polymers and other materials is the high molecular weight of chain polymers. If we consider the alkane series, there is a progressive... 

Interfacial Bonding between Polymers and Other Materials. As... 

Phagocytosis is a process by which foreign or old autologous proteins are ingested by the cell and then removed by fusion with lysosomes these structures are vesicles containing hydrolytic enzymes. Lysosomes (Figure 1.5) are membrane-bound vesicles that are used to break down proteins, nucleic acids, sugar polymers, and other materials that are either extracellular or... 

Struik L, "Physical Aging of Amorphous Polymers and other Materials", Elsevier, Amsterdam, 1978. 

Struik LCE, "Physical Aging in Amorphous Polymers and Other Materials", p 26, Elsevier, Amsterdam/London/New York, 1978. 

---