One of the advantages of manufacturing with polymers in general is that several functions can be integrated in one component. For example, if the part was made with metal, different materials should be used for the different functions, leading to additional costs related to the assembly . For example, some functions can be integrated in one plastic component using snap fits, pipe connectors, seals, sliding bearings, threads, gear racks, and reinforcements (ribs). In some cases, it is impossible to fulfill all the requirements with one polymeric material, so it is very usual to find products with two materials that are processed at the same time or in the same mold in a special type of injection molding called co-injection molding or multishot injection molding (MSM).
There are numerous methods for producing plastic parts and many will be discussed in this post. Of the various processes, molding and extrusion are the most predominant. The best method will depend on the polymer being used, the part geometry, and the part’s function. The definition of plastic molding is it is a group of manufacturing processes used with a closed tool called a mold, to produce parts. The inside of the mold is in the shape of the part, when the high temperature mold is filled with the molten polymer and closes, the part is formed during the curing. Extrusion is another polymer processing method that can be used to produce plastic parts that are typically linear in shape. The extrusion process also uses hot molten plastic and a heated tool, however the extrusion tool is an open tool, called a die.
In the United States, the Food and Drug Administration (FDA) is the entity in charge of approving materials that come into contact with human body, based on the material’s biocompatibility and biostability properties. There are a variety of methods that can be used to verify a material’s properties. However not all materials will require testing, the FDA states “if there is sufficient knowledge about the biocompatibility and toxicity of the material, then it is not necessary for further biocompatibility testing”.
Green Manufacturing (GM) can be defined as “manufacturing methods that support and sustain a renewable way of producing products and/or services that do not harm to the environment” . When the social and technological aspects of design, the reduction of environmental and health risks, worker protection and the use of the products are also included, we are talking about Environmentally Conscious Design and Manufacturing (ECD&M) . It may sound simple in words but the implementation of this methodology in a company requires the organization of production operations, management functions and personnel to facilitate the minimization of technical efforts and wastes .
Light can be defined as electromagnetic radiation which has different frequencies and wavelength. The spectrum that can be picked up by the retina of a human eye is called visible light . Materials through which light can refracted, reflected, transmitted, dispersed, polarized, detected and transformed are called optical materials .