Rotation and Heating

Process in which tubular products are fabricated through the application of resin and glass strand reinforcement to the inside of a mold that is rotated and heated. The process polymerizes the resin system. 

The MM2 force field3 is probably the most extensively parameterized and intensively used force field to date. It reproduces a variety of molecular properties such as geometry, dipole moments, conformational energies, barriers to rotation and heats of formation. Of particular importance for calculations of amines is that MM2 treats lone pairs on sp3 nitrogens (and oxygens) as pseudo atoms with a special atom type and parameters. A closely related force field, MM2 7, was derived from MM2 by Osawa and Jaime. MM2 uses the same potential functions as MM2, but employs a different set of parameters in an attempt to better reproduce barriers to rotation about single C—C bonds. 

Rotational Casting. Like rotomolding, the plastisol is poured into a cold mold, which is rotated and heated to gel the plastisol onto the walls of the mold. It is then heated to fuse, cooled to solidify, opened, and the product removed. Typical products are volley balls, basketballs, dolls, and auto parts. 

Experiments with gaseous reactants (propane and isobutane. Table III) were carried out by charging the liquefied gas from a weighed stainless-steel sampling cylinder into the sealed autoclave containing hydrochloric acid and, when used, a liquid alkane after which ethylene was charged and the autoclave was rotated and heated. 

The capillary is made in three operations. First, a 6-in. length of 6-mm glass tubing is rotated and heated in a small area over a very hot flame to... 

The use of biaxial rotation and heat for materials fabrication dates to R. Peters of Britain in 1855 for the manufacture of hollow artillery shells [41,42]. Rotational molding of polyethylene started in the early 1950s. 

Solvent is evaporated at 55°C under a gentle stream of nitrogen. Once perfectly dried, sample is then redissolved in the derivatizing reagent (80 p,L of 3N HCl in n-butanol). Vial is capped, rotated, and heated at 65°C for 20 min. 

This is the simplest and least costly form of the equipment but it requires the most labor. The mold is rolled into the oven for rotation and heating. The mold is moved out at the end of the cycle and another mold... 

Internal rotation and heat capacity of a few polymers at low tempera-... 

Figure 19 Steps involved in rotational molding, (a) Loading resin powder into the mold (b) rotating and heating (e) rotating and cooling (d) product removal.

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