Abstract: A thermal expansion valve unit comprises a closed vapor system, which includes a temperature sensing chamber in thermal communication with a source such as a two phase refrigerant, and a pressure chamber with a deformable member, the position of which controls the size of an expansion orifice. A line confining a selected vapor, which optionally may be a refrigerant, communicates between the interiors of the temperature sensing chamber and the pressure chamber. A heater, separately controllable, is thermally coupled to the temperature sensing chamber such that the selected refrigerant may be independently heated to change the pressure in the chamber. A thickness of insulating material is disposed between the temperature sensing chamber and the source to limit thermal energy loss to refrigerated elements in the system.

Abstract: A novel process has been developed for the crystallization of poly(ethylenenaphthalenedicarboxylate) (PEN) and its copolymers. The process comprises the step of maintaining the amount of water in said poly(ethylenenaphthalenedicarboxylate) below a critical moisture content ceiling throughout processing such that a separate drying step is not required.