Strong plastic

Humidity does not affect the permeabihty, diffusion coefficient, or solubihty coefficient of flavor/aroma compounds in vinyhdene chloride copolymer films. Studies based on /n j -2-hexenal and D-limonene from 0 to 100% rh showed no difference in these transport properties (97,98). The permeabihties and diffusion coefficients of /n j -2-hexenal in two barrier polymers are compared in Table 12. Humidity does not affect the vinyhdene chloride copolymer. In contrast, transport in an EVOH film is strongly plasticized by humidity. 

A.B. Strong, Plastics Materials and Processing, 3rd ed., Prentice Hall, New Jersey, 2006, ISBN-13 0131145580. 

The next products developed were the thermoplastics made by vinyl polymerization. Vinyl chloride, and vinyl acetate copolymers known as Vinylite, was one of the first produced by Carbide and Carbon. It had been worked on in Europe and had also been worked on by Ostromysslenski, a chemist with the U. S. Rubber Company. The Carbide chemists realized at an early date that to get a uniform composition it was necessary to adjust the feed ratios of the two monomers to get a proper combination in the reactor to give a constant composition to the product. The next major development of a vinyl product was in the development of Lucite or Plexiglas polymers, which are clear, strong plastics. 

A very clear, transparent, strong plastic Good mechanical properties High impact strength Good thermal and oxidative stability... 

Figure 7.62 Schematic diagram of (a) corotating and (b) counterrotating twin screws. Reprinted, by permission, from A. B. Strong, Plastics Materials and Processing, 2nd ed., p. 365. Copyright 2000 by Prentice-Hall, Inc.

Butene is used in the plastics industry to make both homopolymers and copolymers. Polybutylene (1-polybutene), polymerized from 1-butene, is a plastic with high tensile strength and other mechanical properties that makes it a tough, strong plastic. High-density polyethylenes and linear low-density polyethylenes are produced through co-polymerization by incorporating butene as a comonomer with ethene. Similarly, butene is used with propene to produce different types of polypropylenes. 

Propylene (C3H6) is a gas with chemical, physical, and toxicological properties very similar to those of ethylene. It, too, is a simple asphyxiant. Its major use is in the manufacture of polypropylene polymer, a hard, strong plastic from which are made injection-molded bottles, as well as pipes, valves, battery cases, automobile body parts, and rot-resistant indoor-outdoor carpet. 

The Abrac A (Bush Roake Allen Ltd., London) belong to this class. In addition to their stabilizing properties, all these products have a strong plasticizing action, thus making possible a reduction in the quantity of other plasticizers used. Besides low volatility they show a low tendency... 

Preparation. HF should not be used at full (bottle) strength (typically 48%). A 5% to 10% solution is best. Once prepared, it should be stored in a polyethylene or other strong plastic container that can be closed. Because HF is a glass stripper, do not store the acid solution in a glass container. HF, at any concentration, should always be stored in a fume hood. 

Figure 5.15(c) represents the case where there is a preference for penetrant-penetrant pairs to be formed, such that solubility increases with the concentration of penetrant in the polymer. This type of behavior is observed in systems where the polymer is strongly plasticized by the penetrant, and localized penetrant clusters form, into which additional penetrant molecules preferentially accumulate. 

Low molecular weight substances offering a hi dipole moment, such as nitriles, amides, nitro compounds, etc., (Table 3) have a strong plasticization effect on poly-... 

The last kind of speargun requires ittle alteration and works on the ame principle as gas powered spear-uns. On the small home fire extinguishers there is usually a nozzle through which the fire extinguishing substance Is emitted. On some units there is a cone shaped pipe connected to this, which can easily be taken off, leaving nothing but the short nozzle, if this nozzle is plastic, a strong plastic sealant can be used... 

A large X-ray line broadening in both (1- and /-phases in compacted samples (Fig. 3) is an evidence of a strong plastic deformation in compact samples sintered under high quasihydrostatic pressure. 

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