Rotational moulding machine (1) comprising a fixed frame (2), a support arm (3) comprising a first (4) and a second portion (5) rigidly joined together, the support arm (3) being rotationally fixed to the fixed frame (2) only at the first portion (4) to rotate about a first axis of rotation (101) substantially horizontal, a movable frame (6) rotationally fixed to the support arm (3) to rotate about a second axis of rotation (102) substantially perpendicular to the first axis of rotation (101), the movable frame (6) comprising a supporting portion (7) lying in a plane substantially perpendicular to the second axis of rotation (102), and an actuation system (8) rigidly fixed to the movable frame (6) at the supporting portion (7) and structured to secure a mould (20) and rotate the mould (20) about a third axis of rotation (103) substantially perpendicular to the second axis of rotation (102).

Rotational moulding machine (1) comprising a fixed frame (2), a support arm (3) comprising a first (4) and a second portion (5) rigidly joined together, the support arm (3) being rotationally fixed to the fixed frame (2) only at the first portion (4) to rotate about a first axis of rotation (101) substantially horizontal, a movable frame (6) rotationally fixed to the support arm (3) to rotate about a second axis of rotation (102) substantially perpendicular to the first axis of rotation (101), the movable frame (6) comprising a supporting portion (7) lying in a plane substantially perpendicular to the second axis of rotation (102), and an actuation system (8) rigidly fixed to the movable frame (6) at the supporting portion (7) and structured to secure a mould (20) and rotate the mould (20) about a third axis of rotation (103) substantially perpendicular to the second axis of rotation (102).

A method of preparing a carboxylic acid-modified nitrile-based copolymer latex is provided. The method of preparing a carboxylic acid-modified nitrile-based copolymer later includes emulsion-polymerizing a monomer mixture including a conjugated diene-based monomer, an ethylenically unsaturated nitrile-based monomer, and an ethylenically unsaturated acid monomer in the presence of a cross-linking agent including glyoxal.

A method of preparing a carboxylic acid-modified nitrile-based copolymer latex is provided. The method of preparing a carboxylic acid-modified nitrile-based copolymer later includes emulsion-polymerizing a monomer mixture including a conjugated diene-based monomer, an ethylenically unsaturated nitrile-based monomer, and an ethylenically unsaturated acid monomer in the presence of a cross-linking agent including glyoxal.

The rotational molding system comprising an internal air cooling system disposed on the mold and configured for one or more of selectively controlling air flow into or out of a cavity of the mold for actively cooling an interior surface of a part, pressurizing the cavity of the mold, allowing pressure equalization, or venting of off-gases. A first thermocouple and a second thermocouple disposed within the cavity to measure a temperature at the exterior surface of a part and the mold cavity. A control system in electronic communication with both said first thermocouple and said second thermocouple, may selectively operate the internal air cooling system to maintain the temperature of the cavity and the part's outside surface substantially the same. The mold and/or the oven containing the mold may be disposed for rotation about a first axis and a second axis during the rotational molding process.

The rotational molding system comprising an internal air cooling system disposed on the mold and configured for one or more of selectively controlling air flow into or out of a cavity of the mold for actively cooling an interior surface of a part, pressurizing the cavity of the mold, allowing pressure equalization, or venting of off-gases. A first thermocouple and a second thermocouple disposed within the cavity to measure a temperature at the exterior surface of a part and the mold cavity. A control system in electronic communication with both said first thermocouple and said second thermocouple, may selectively operate the internal air cooling system to maintain the temperature of the cavity and the part's outside surface substantially the same. The mold and/or the oven containing the mold may be disposed for rotation about a first axis and a second axis during the rotational molding process.

A cushion for a hot tub or spa is molded in a rotational molding process. The cushion includes a decorative outer surface made from a plastic material (e.g., an outer wall and side walls, etc.). The cushion includes a a back surface for interfacing with a hot-tub shell or spa shell with at least one projection extending from the back surface towards the decorative surface. The at least one projection is for supporting the force of an object that is resting on the cushion. The cushion if formed in a rotational molding process.

A cushion for a hot tub or spa is molded in a rotational molding process. The cushion includes a decorative outer surface made from a plastic material (e.g., an outer wall and side walls, etc.). The cushion includes a a back surface for interfacing with a hot-tub shell or spa shell with at least one projection extending from the back surface towards the decorative surface. The at least one projection is for supporting the force of an object that is resting on the cushion. The cushion if formed in a rotational molding process.

A ribbon liquefier comprising an outer liquefier portion configured to receive thermal energy from a heat transfer component, and a channel at least partially defined by the outer liquefier portion, where the channel has dimensions that are configured to receive the ribbon filament, and where the ribbon liquefier is configured to melt the ribbon filament received in the channel to at least an extrudable state with the received thermal energy to provide a melt flow. The dimensions of the channel are further configured to conform the melt flow from an axially-asymmetric flow to a substantially axially-symmetric flow in an extrusion tip connected to the ribbon liquefier.

The invention is a method of manufacturing a multi-color molded furniture item made by a multi-step molding process using heat zone control in the mold to apply different plastic charges to predefined portions of the mold. Controlling zones of the mold with heat by zone heating and thermal insulators separating mold zones for molding a part of different plastics differing in characteristics such as color, durability, surface finish and chemical resistance.