Poly-para-xylylene

Several studies have concerned the microstnicture of lamellae in materials such as the block copolymers polystyrene-h/oc/r-poly-l-vinylpyridine [139] and polystyrene-h/oc/r-polybutadiene [140], as well as single crystals of poly-para-xylylene [139], and reveal features (such as intersecting lamellae (figure Bl.19.29)) that had not been previously observed. 

Fortin, J. B. Lu, T. M., Ultraviolet radiation induced degradation of poly para xylylene (parylene) thin films, Thin Solid Films 2001, 397, 223 228... 

Chemical vapor deposition (CVD) of poly(para-xylylene carboxylic acid pentafluorophenolester-co-para-xylylene] (PPX-PPF) on PDMS can prevent it from solvent swelling [262]. 

The process of parylene polymerization is presented schematically in Figure 5.2 using parylene N, unsubstituted poly(para-xylylene). Parylene dimer is heated until it sublimes. The dimer vapor passes through a high temperature pyrolysis zone where it cracks and becomes monomer vapor, i.e., monomer is created in vacuum. The monomer polymerizes and deposits in the deposition chamber, which is usually at room temperature. Parylene polymerization completed in a vacuum is a process involving no solvents, no curing, and no liquid phase. Its use essentially eliminates concern about the operator s health and safety, air pollution, and waste disposal. 

Parylene C, or monochloro-substituted poly(para-xylylene), is a polymer that has excellent bulk mechanical properties as well as excellent barrier properties for... 

Soluble polyimide prepared by reaction of (6F) with l.S-diaminonaphthalene-Soluble polyimide prepared by reaction of (6F) 4th 1,4-diaminobenaene. Poly(para-xylylene) Unkm Carbide Reg. trademark. 

Soluble polyimide prepared by reaction of 4,4 -hexafluoroisopropylidene diphthalic anhydride (6F) with 3,5-diaminobenzoic acid. b Soluble polyimide prepared by reaction of (6F) with 1,5-diaminonaphthalene. c Soluble polyimide prepared by reaction of (6 F) with 1,4-diaminobenzene. d Poly(para-xylylene) Union Carbide Reg. trademark. e Dupont 100 CA-43. f Union Carbide Sulfone 47. 

A chapter focusing on the use of nanocomposites in electrochemical devices is presented by Schoonman, Zavyalov, and Pivkina. A wide range of metal (metal ox-ide)/polymer nanocomposites has been synthesized using Al, Sn, Zn, Pd, and Ti as a metal source and poly-para-xylylene (PPX) as a polymeric matrix. The properties of the nanocomposites were studied by comparing structure, morphology, electrical properties, oxidation kinetics, and electrochemical parameters. 

Schulze S, Schafer M, Greiner A, Weitzel KM. Bombardment induced ion transport - part III experimental potassium ion conductivities in poly(para-xylylene). Phys Chem Chem Phys 2013 15(5) 1481. 

M. Szwarc, Poly-para-xylylene Its chemistry and application in coating technology, Polym. Sci. Eng. 16, 473 (1976). 

Poly(para-xylylene) Union Carbide registered trademaric. 

Parylene N, poly(para-xylylene), the basic member of the series, is a completely linear, highly crystalline material. It is a primary dielectric, exhibiting a very low-dissipation factor, high-dielectric strength, and a low-dielectric constant invariant with frequency. This form has the highest penetrating power of all the Parylenes (with exception for Parylene HT, see later in this section). 

Another example is poly-para-xylylene (Parylene), which is obtained by the generation, through pyrolysis, of radicals of a para-xylylene dimmer that readily polymerize on a substrate held at room temperature. This is a solvent free process so that the polymer can be deposited on any kind of substrate, including organic ones. Although the main application of parylene remains encapsulation [49], its dielectric properties have also been put into profit to use it as a gate dielectric [50,51]. 

Fig. 8. Comparison of the ATR spectra of a polyethylene sample coated with poly-para-xylylene recorded using a Germanium (45 ) and KRS-5 (60 ).

Figure 8 shows an example of the depth-profile study using the ATR technique. The sample was vapor deposited poly-para-xylylene on polyethylene. The Figure shows the ATR spectra of the sample recorded using a germanium (45°) crystal and a KRS-5 (60O) crystal. These last... 

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