Rotomolding

Rotomolding. Nylon-6, nylon-11, and nylon-12 can be used in rotomolding and are generally suppHed for these appHcations as a powder or with a small pellet si2e. The process involves tumbling the resin in a heated mold to form large, thin-walled mol dings. Nylon-11 and nylon-12 use mold temperatures of 230—280°C and nylon-6 is processed at over 300°C. An inert gas atmosphere is preferred to avoid oxidation. 

Spray ing/bru shing/rolling Resin transfer molding Rotational casting Rotomolding Thermoforming Compounding/vulcani-zation... 

Rotational molding, of linear low density polyethylene, 20 200. See also Rotomolding... 

Rotomolding machine, 19 554 Rotomolding, of high density polyethylene, 20 175... 

Advances in Materials and Processes in Rotomolding. Proceedings of a conference held Independence, Ohio, 9th-11th June 2002. 

New York City, 2nd-6th May, 1999, p.1457-67.012 COMPARISON OF DRYING BLENDING-BASED AND MELT COMPOUNDING-BASED ROTOMOLDING TECHNIQUES FOR LLDPE FOAMS... 

Film, 72% injection molding, 9% rotomolding, 6% wire and cable, 3% miscellaneous, 10%... 

In rotational molding, also known as rotomolding, the mold (or cavity) is filled with material, either as a solid powder or liquid. The mold is closed, placed in a heated oven, and then rotated biaxially. The mold is then cooled, opened, and the article recovered. Powders of about 35 mesh (500 pm) are typical though different sizes are also employed. The distribution of particles and additives is determined by the mixing/rotation ratio. 

Polyethylene is readily fabricated by all methods of thermoplastic processing. The principal methods used are film and sheet extrusion, extrusion coating, injection molding, blow molding, pipe extrusion, wire and cable extrusion coating, rotomolding, and hot melt and powder coatings. 

Figure 3.74 Typical air temperature in the mold while rotomolding polyethylene parts.

Electrostatic powder coating using fine powders and rotomolding and lining using very fine pellets are other processing methods. Formulated primers are used to improve adhesion and moisture permeability for powder-coated metal substrates. For roto-lining, primers are usually not used.31... 

Other applications include rotomolded tanks and containers for the storage of corrosive chemicals, such as nitric or hydrochloric acid. Extruded sheets can be thermoformed into various parts, such as battery cases for heart pacemakers.58 ECTFE film is used as release sheet in the fabrication of high-temperature composites for aerospace applications. Braided cable jackets made from monofilament strands are used in military and commercial aircraft as a protective sleeve for cables.59... 

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. 

E-mail Address info rotomolding.org Web Address www.rotomolding.org Association of Rotational Molders (ARM) International represents the worldwide plastics rotational molding industry. 

Chroma Corp., McHenry, IL, Attention Rotomolders Clean Air Mixers Faster, PT, Sep. 2002. 

Henkel Loctite, Rotomolding Release Suits Multiple Releases, MP, Oct. 2002. 

New Single-Site Technology Produces LLDPEs for Film, Injection, and Rotomolding, PT, Sep. 2005. 

Other applications include rotomolded tanks and containers for the storage of corrosive chemicals, such as nitric or hydrochloric acid. Extruded sheets can be thermoformed into various parts, such as battery cases for heart pacemakers... 

This two-day seminar was presented in Atlanta, GA May 18-19, 1988 by Technomic Publishing Co., Lancaster, PA. It covered rigid, flexible, reticulated, syntactic, sintered, microporous, bead and rotomolded foams. 

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