Polymer tubing

Other tubes (long duration detector tubes, porous polymer tubes etc.)... 

Polymer synthesis, advances in, 20 442 Polymer tacticity, 20 533 Polymer tubing, aeration through,... 

Keywords. Viscoelasticity, Molecular rheology. Branched polymers. Tube model, Non-Newtonian flow... 

Porous polymers are usually most useful for the collection of high molecular weight and nonvolatile substances such as pesticides. They may also be suitable for sampling many of the compounds for which charcoal and silica gel methods have been validated. However, since charcoal and silica gel tubes are less expensive than porous polymer tubes, are commercially available, and are already widely used, they are the favored media. 

Plasticizer. The polymer tubing extractor contains the plasticizer l,2-bis(ethylhexyl) phthalate. Longer exposures to 0.1 M NaOH indicated that electroactive hydrolysis products of plasticizer, probably ethyl and hexyl alcohols, were produced, as suggested by the following peak currents given in nanoamperes (the times of the peak currents are given in parentheses) 30 (2 min), 7 (1 min), 5 (30 s), and 2 (15 s). The analytical procedure presented here uses back extraction times of less... 

Mixer inlay material Metals such as nickel or silver to a lesser extent silicon, stainless steels, polymers Tubing diameter 50 pm... 

Fig. 24.6. Inside an acid cooler. Fig. 9.5 gives an external view. Tubes start through the tube sheet , shown here. They extend almost to the far end of the cooler where there is another tube sheet . Cool water enters at this end and flows through the tubes to the far end. Between the tube sheets , the tubes are surrounded by warm acid moving turbulently around them. Heat transfers from the warm acid to the cool water (through the tube walls). The tube entering from the right contains a thermocouple. The polymer tubes in the foreground surround metal rods. The rods are bare between the tube sheets. An electrical potential applied between them and the water tubes anodically protects the tubes against acid side corrosion.

Rajamehendran intravaginal device 17 3-estradiol/ progesterone Poly(dimethylsiloxane) Two C-shaped polymer tubes (impregnated with active substances) tied together, forming umbrella-shaped device Excellent vaginal retention not commercially available... 

Apparatus. Reactions using HF were carried out in translucent fluorocarbon polymer tubing (FEP)(CHEMPLAST Inc., Wayne NJ 07470) heat sealed at one end and joined via compression fittings to a Teflon valve to a metal vacuum line equipped for fluorine handling as previously described [6,17]. 

Apparatus and Technique, All reactors were constructed in T shape from translucent fluorocarbon polymer tubing (FEP) (Chemplast, Inc., Wayne, NJ 07490) joined with Teflon Swagelok compression fittings and equipped with Teflon body valves, having Kel-F stems... 

The plastic is heated to a melted or viscous state and a section of molten polymer tubing (parison) is extruded usually downward from the die head into an open mold. The mold is closed around the parison, sealing it at one end. Compressed air is blown into the open end of the tube, expanding the viscous plastic to the walls of the cavity, thus forming the desired shape of the container. The material cools in the cavity and solidifies. The mold is opened and the molding is removed. This technique is used for the manufacture of bottles, toys, and large containers. 

The polymer tube is allowed to cool to room temperature and the vacuum released by opening the Young s tap the partial soluble and the swollen polymer is poured into a beaker (1 L) containing and excess of methanol (400 mL). The material is collected then swollen in dichloromethane (ca. 50 mL) and then precipitated into methanol (500 mL), and once again the solid collected. Finally, a further portion of dichloromethane is added and the... 

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