Abstract: An injection molding assembly configured for use with an injection molding machine includes a mixing chamber configured for receiving a flowable molding material and a nozzle assembly connectable to the mixing chamber. The nozzle assembly includes a cap removably connectable to the mixing chamber for enclosing the mixing chamber, and a nozzle extending through the cap and configured to deliver the flowable molding material from the mixing chamber to a mold. The nozzle is rotatable relative to the cap when the cap is connected to the mixing chamber. Also disclosed is an injection molding machine having a feeding device for feeding a flowable molding material, a mixing chamber configured for receiving the flowable molding material from the feeding device, and the nozzle assembly.

Abstract: Provided is a method for preparing a polymeric article including introducing a polymerizable composition into a mold; sealing the composition within the mold using a sealing means; placing the mold into a convection cure oven; subjecting the polymerizable composition to a cure cycle sufficient to partially cure the composition; extracting the mold from the convection cure oven; optionally, removing the sealing means from the mold; placing the mold into an auxiliary curing chamber which is placed into the convection cure oven, or placing the mold into an auxiliary curing chamber which is within the convection cure oven; subjecting the polymerizable composition to a further cure cycle to complete polymerization of the composition, thereby forming a cured polymeric article; and removing the cured polymeric article from the mold.

Abstract: Provided is a method for preparing a polymeric article including introducing a polymerizable composition into a mold; sealing the composition within the mold using a sealing means; placing the mold into a convection cure oven; subjecting the polymerizable composition to a cure cycle sufficient to partially cure the composition; extracting the mold from the convection cure oven; optionally, removing the sealing means from the mold; placing the mold into an auxiliary curing chamber which is placed into the convection cure oven, or placing the mold into an auxiliary curing chamber which is within the convection cure oven; subjecting the polymerizable composition to a further cure cycle to complete polymerization of the composition, thereby forming a cured polymeric article; and removing the cured polymeric article from the mold.

Abstract: Described is a method of preparing a cured, non-elastomeric polymeric sheet derived from a polyisocyanate. The method comprises the following steps: combining a first component and second, separate component to form a reaction mixture; introducing the reaction mixture into a preheated sheet mold at a certain minimum fill rate, allowing the reaction mixture to gel; heating the reaction mixture to a temperature and for a time sufficient to yield a cured sheet having a thickness of at least 6.35 mm (0.25 in); and removing the cured sheet from the mold to yield a non-elastomeric polymeric sheet. When the active hydrogen functional groups in the second component include hydroxyl groups, the first and second components are initially heated to a temperature of at least 50° C., Polyurethane sheets formed by such processes demonstrate minimal optical defects and the process allows for the production of superior sheets of higher thicknesses than previously possible.