Applications rotomolding

Rotomolding. Nylon-6, nylon-11, and nylon-12 can be used in rotomolding and are generally supplied for these applications as a powder or with a small pellet size. The process involves tumbling the resin in a heated mold to form large, thin-walled moldings. 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. 

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... 

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... 

MAJOR APPLICATIONS Major applications include blown and cast films for bags, shrink-wrap, packaging, and injection molding. Such films exhibit exceptional toughness, dart impact, and puncture resistance when compared to blown films of LDPE. Other applications include blow molding, pipe and conduit, lamination, coextrusion, rotomolding, and wire and cable coatings. There is considerable use of blends of LLDPE with LDPE in a wide variety of applications. 

Melt processable nylons are needed for the application of this polymer to plastic products. They are fabricated by injection molding, extmsion, rotomolding, and powder coating. Recently, novel fabrication processes accompanying chemical reactions have been developed with significant commercial importance. The reaction injection molding, reactive extmsion, and reactive blending are typical examples. 

Plastics are available in the form of pellets, granules, and powder which can be extruded, blow molded, injection molded or rotomolded to fabricate products. In the global markets over many years, plastics have proven their utility and cost effectiveness. Even though the markets are mature, applications are continually being developed. New applications and developing markets are expected to increase the growth of plastics [8]. 

As of 2009, resins with Melt Index (L, ) values from about 0.5 to 20 and densities of 0.912-0.945 g/cc are available from Chevron Phillips Chemical Company for film, rotomolding and injection molding applications. The film applications would be for high strength and/or high clarity requirements [6]. 

Ideal non-tank applications for rotational molding are typically complex hollow forms in relatively low quantities (up to approximately 10,000 parts). There are obvious exceptions to this, for example children s toys. But for the most part, rotomolding offers benefits to end-users with low upfront costs in tooling and equipment and the ability to render almost any design that the molder can conceive. 

The process is inherently a low pressure one and is closely tied in many respects to die processing attributes of polyethylene. Material choices outside the polyethylene p ette are limited in comparison to other processes and thus rotomolding does not always suit applications that have more demanding performance criteria. Tolerance control, surface finish, and part stiffness are among the most common challenges. 

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