Poly vapor transport

Tanigaki, N., et al. 2005. Dye doping of poly(p-phenylenevinylene)s by vapor transportation for photovoltaic application. Jpn J Appl Phys 44 630. 

Using this TGA/WVT capsule technique, vapor transport data have been collected not only for glassy PC and rubbery silicone films as reviewed here but also for crystalline films of poly(ethylene terephthalate) (PET) and a microporous Gortex membrane (Holcomb and Bair 2005). With a small modification this WVT capsule can be employed to confine volatile reactive liquids such as the UV-curable materials studied in DPC work at elevated temperatures (see Section 2.11, on differential photocalorimetry). 

FIGURE 3.13 UV-vis spectra of VUV-irradiated PLA membranes for 3,6,10, 30,60, and 100 min. (Reprinted from Desalination, 287, S. Sato et al.. Effects of irradiation with vacuum ultraviolet xenon excimer lamp at 172 nm on water vapor transport through poly[lactic acid] membranes, 290-300. Copyright 2012, with permission from Elsevier B.V.)... 

Sato S. et al. 2012. Effects of irradiation with vacuum ultraviolet xenon excimer lamp at 172 nm on water vapor transport through poly(lactic acid) membranes. Desalination... 

Poly(naphthalene) and poly(tetrafluoronaphthalene) were synthesized by vaporizing the appropriate precursor in vacuo and transporting the vapor into a hot chamber maintained at 150-400°C. In the high-temperature zone, the... 

I. Pinnau and L.G. Toy, Transport of Organic Vapors through Poly[l-(trimethylsilyl)-... 

Later researchers followed essentially the same process, substituting monomer precursors instead of the dimer, to produce PPV films. " The monomers were evaporated and the vapors carried into the pyrolysis chamber, where they were pyrolyzed at 800°C. The reactant species were then transported to the substrate maintained at 60°C to form the precursor polymer film. This film was then thermally converted to PPV at 150-320°C. - Scafer et al. have further shown that PPV can be produced via the dehydrogenation route introduced by Iwatsuki et al. They showed that soluble a-phenyl substituted poly-p-xylylene can be prepared by CVP of l-a-chlorobenzyl-4-methylbenzene. The parylene was then dehydrogenated by DDQ resulting in PPV. This process could be used to produce both segmented and unsegmented PPVs. The segmentation ratio was controlled by the molar ratio of the parylene to DDQ, in the... 

Transport in semi-crystalline polymers can, thus, be treated on the basis of a simple two phase model, consisting of a dispersed impermeable crystalline phase in a permeable amorphous matrix. Lasoski and Cobbs (12) attempted to correlate the solubility of water vapor in unoriented poly(ethylene terephthalate) and nylon 610 with... 

In thermal debinding, the binder is removed as a vapor by heating at ambient pressure in an oxidizing or nonoxidizing atmosphere or under a partial vacuum. The process is influenced by both chemical and physical factors. Chemically, the composition of the binder determines the decomposition temperature and the decomposition products. Physically, the removal of the binder is controlled by heat transfer into the body and mass transport of the decomposition products out of the body. In practice, binder systems consist of a mixture of at least two components that differ in volatility and chemical decomposition. The ceramic powder may alter the decomposition of the pure polymer. In view of the complexity of real systems, we first consider the basic features of thermal debinding for a simplified system consisting of a powder compact with a single binder, e.g., a thermoplastic polymer such as poly(methyl methacrylate) or polyethylene. Later,... 

Miguel, O., Femandez-Benidi, M. J., and Iruin, J. J. (1997). Survey on Transport Properties of Liquids, Vapors, and Gases in Biodegradable Poly(3-hydroxybutyrate) PHB. Journal of Applied Polymer Science 64, 1849-1859. 

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