Oriented polyvinyl chloride

Piezoelectric effect in oriented polyvinyl chloride and polyvinyl fluoride. 

OC operating characteristic OPVC oriented polyvinyl chloride... 

Rawson, F.F. and Rider, J.G. (1974) Elastic constants of oriented polyvinyl-chloride. 

A more comprehensive investigation on uniaxially oriented sheets of polymethylmethacrylate and polystyrene was undertaken by Wright et al. [94] using ultrasonic measurements. The results are summarised in Figure 8.29 (a) and (b), where the stiffness constants are shown as a function of the birefringence. Rawson and Rider [95] have also reported ultrasonic data for oriented polyvinyl chloride and observed a similar degree of anisotropy to that seen in Table 8.8 from Hennig s work. 

The key industrial applications and markets for normal and isobutanol and 2-ethylhexanol are discussed. As will be noted, the C4 oxo alcohols find use primarily within the coatings industry, either as solvents, per se, or as intermediates to manufacture solvents or protective coatings chemicals. Applications for 2-ethylhexanol, while numerous and varied, are basically oriented toward the manufacture of plasticizers for polyvinyl chloride. Total U.S. consumption of these alcohols in 1979 was approximately 1.3 billion pounds -730 million pounds of n-butanol, 190 million pounds of isobutanol, and 380 million pounds of 2-ethylhexanol. The consumption pattern is summarized in Table II and described in the following sections ... 

Sodium ion-selective field-effect transistors (Na+ ISFETs) were prepared by using three different types of polymeric matrix materials, such as polyvinyl chloride, bio-compatible polymer (polyurethane) and Urushi (natural oriental lacquer). Their electrochemical characteristics were discussed in connection with their characteristics of polymeric matrix membranes. 

Shindo, Y., Read, B. E., Stein, R. S. The study of the orientation of polyvinyl chloride films by means of birefringence and infrared, visible and ultraviolet dichroism. Makromol. Chem. 118,272 (1968). 

Orientation can be applied to films, sheets and containers. Recent examples in containers have used polyester, polyvinyl chloride and polypropylene. In these orientation processes, called stretch and blow in the case of containers, polyester and polyvinyl chloride achieve excellent clarity, and polypropylene considerably improved clarity. It should be noted that orientation of plastics with relatively low to medium melting points frequently will not allow autoclaving by steam or hot filling, since distortion or deorientation will occur. 

Presently, the amount of data on transport in uniaxially oriented amorphous polymers is small in comparison with that of semicrystalline materials. The transport properties of oriented natural rubber (22), polystyrene (i3.,ii), polycarbonate (22.), and polyvinyl chloride (22,22) among others have been reported. One of the more complete descriptions of the effects of uniaxial orientation on gas transport properties of an amorphous polymer is that by Wang and Porter (34) for polystyrene. 

Figure 4.23 shows a snap connector (400) which can be mounted on the wide vertical side of a wood joist to facilitate securement of the vertically oriented plastic extrusions. The snap connector (400), which is made of an extruded polyvinyl chloride material, includes an elongated base (401) having a pair of opposed elongated end flanges (402) and (404). Each flange (402,404) includes a first section (406,408) which extends perpendicularly to the base (402) and a second section (410,412) which in turn extends perpendicularly from the first section (406,408). Each second section (410,412) includes a pilot surface (414,416). The flanges (402,404) each define a recessed space (418,419). The snap connector also... 

The next problem was that of coalescing emulsion particles and giving oriented fiber structure to polyvinyl chloride. As will be shown below, it was confirmed that the oriented fiber structure is realized in the hot-drawing of the spun filament in dry air. 

The preceding discussion has to do with induced dipoles whereas, the relaxation studies deal with the motions of parts of polymer chains that have different relaxation times for orientation. Many polymers such as polyvinyl fluoride, polyvinyl chloride and nylons have permanent dipoles that may be reoriented on the application of an applied field. The response of the oriented permanent dipoles will vary with the strength of the applied field. 

This method has also been applied to non-crystalline or very poorly crystalline polymers, viz. polymethylmethacrylate and polyvinyl chloride. In these cases, the lattice sums were calculated by assuming that the magnetic anisotropy arises entirely from the intramolecular interactions, and that the intermolecular interactions are isotropic. The lattice sums for the intramolecular interactions are then calculated on the basis of a model for the molecular chain, and the intermolecular interactions give a small additional term in the So lattice sum which can be found from a least squares fit to the data. It was found that the adjusted value of Sq was constant for samples of differing degrees of orientation thus justifying the initial assumptions. 

In a series of related publications, Hennig has reported the measurements of elastic constants for oriented polymers which are either amorphous or of low crystallinity. In his earliest work." Hennig showed that in polyvinyl chloride and polymethylmethacrylate the relationship 3/Eo = S33 + 2S11, where is the modulus of the isotropic polymer, holds to a good approximation. Results for the anisotropy of the linear compressibility y in polyvinyl chloride, polymethylmethacrylate, polystyrene and polycarbonate were also reported. In this experiment Hennig measured the linear compressibility parallel to the draw direction 7ii, and that in the plane perpendicular to the draw direction Vi. For uniaxially oriented polymers yn = 2Si3 + S33 = S i -I-Si2-I-S 3. It was... 

Carbon fibers from isotropic pitch Isotropic pitch or a pitch-like material, such as molten polyvinyl chloride, is melt spun at high strain rates to align the molecules parallel to the fiber axis. The thermoplastic fiber is then rapidly cooled and carefully oxidized at a low temperature (<100 °C). The oxidation process is rather slow, so as to ensure stabilization of the fiber by cross-linking to make it infusible. However, upon carbonization, relaxation of the molecules takes place, producing fibers with no significant preferred orientation. This process is not industrially attractive due to the lengthy oxidation step, and because only low-quality carbon fibers with no graphitization are produced. These fibers are used as fillers in various plastics to form thermal insulation materials. 

Polypropylene is generally used as oriented polypropylene. Polyvinyl chloride film is commonly used in plasticized form. Polyvinylidene chloride is often known as Saran and is generally used in copolymer form with acrylonitrile. Polyethylene terephthalate is a thermoplastic polyester. Polystyrene is sometimes used in biaxially oriented form. Polycarbonates, polysulfones, polyether sulfones, poly-imides, polyetherimides, and several fluoropolymers are also used for specialty applications. 

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