Poly , contact heating

Poly(alkylene glycol)s are also used as lubricity additives ia water-based synthetic cutting and grinding fluids (36), and ia aqueous metalworking fluids. Under the high frictional heating at the tool or die contact with the workpiece, the polyalkylene glycol comes out of solution ia fine droplets which coat the hot metal surfaces. 

A triangular shaped wheel cover with the center cut out to provide hub access was then applied to a wheel. The cover was constructed from a heat shrinkable poly- 10 olefin ftlm. Tape was attached to the apex points of the triangle. The tape liner was removed and the three adhesive sites were fastened to the spokes. As an identical complementary cover was then applied to the opposite face of the wheel in a mirror image fashion. The 1 adhesive contact points were positioned to encapsulate the spoke on either side within the adhesive contact point. Heat was then used to shrink the covers and achieve a wrinkle-free condition. This example demonstrates that design can play a part in providing a stylish wheel cover that is capable of individualizing the bicycle to meet a wide variety of consumer tastes. 

Citric acid esters are used as plasticizers ia plastics such as poly(viayl chloride), poly(vinhdene chloride), poly(viQyl acetate), poly(viQyl butyral), polypropylene, chlorinated rubber, ethylceUulose, and cellulose nitrate. Most citrate esters are nontoxic and are acceptable by the FDA for use in food-contact packaging and for flavor in certain foods. As a plasticizer, citrate esters provide good heat and light stabiUty and excellent flexibiUty at low temperatures. Triethyl citrate, tri- -butyl citrate, isopropyl citrate, and stearyl citrate are considered GRAS for use as food ingredients (224—228). 

Other developments in recent years have been the appearance of tough and heat-resistant materials closely related to poly(methyl methacrylate) and to interesting cross-linked polymers. Amongst these are the so-called hydrophilic polymers used in the making of soft contact lenses. 

Poly-tetrafluoroethylene or -hexafluoropropylene sealing tapes burned vigorously in contact with the alloy in a helium atmosphere [1], A teflon-coated magnetic stirrer bar used to stir the alloy under propane atmosphere ignited when the speed was increased and generated enough heat to melt the glass. Triboelectric initiation was postulated [2],... 

For post-type DTA s in which thermocouple junctions measure the temperature of the container of the sample (e.g. platinum or poly crystalline alumina crucibles), good mechanical contact between the sample and the bottom of the crucible will improve instrument sensitivity to transformations. Surface contact may be optimized by using samples shaped to match the crucible, or finely crushed granules, as opposed to more spherical or odd-shaped chunks. Optimum mechanical contact minimizes the lag time between when a reaction occurs and when heat propagates to/from the point of temperature measurement, and the reaction is recorded. 

In the two-step lithiation, 2 g of 3% crosslinked brominated macroporous poly(styrene-DVB-EVB) beads containing A.36 nmol of Br/g in AO ml of dry toluene under N2 were brought in contact with 1A.8 ml of 1.6 M n-BuLi, and the mixture was heated at 60°C with stirring for 3 hr. After cooling to 25°C, the beads were separated by filtration under N2, washed with dry toluene and then THF, and kept in THF suspension under N2 for further reaction. 

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