Polymers pharmaceutical packaging

The polymers mostly used in pharmaceutical packaging are polyethylene, polypropylene, PVC, polyamide, polystyrol, nylon, cellulose acetate, polyethylene terephthtalate, and blends thereof. Copolymers and rubbers are also used. The DSC melting curve of polyethylene used for packaging purposes is characteristic. Low- and high-density polyethylene are differentiated by their melting points. " Melting point and density of polyethylene are linearily correlated. " Crystallinity may be determined as described above for amorphous state. 

CASE STUDIES POLYMER ADDITIVES IN PHARMACEUTICAL PACKAGING... 

One way of classifying polymers in pharmaceutical applications is to divide them into three general categories according to their common uses (1) polymers in conventional dosage forms (2) polymers in controlled release dosage forms and (3) polymers for packaging. 

In tonnage terms, calcium carbonate is completely dominant a few figures are given in Chapter 6. The great majority of calcium carbonate is used in PVC and to a lesser extent unsaturated polyester thermosetting polymer. Much of it is destined for the construction market or the automotive, domestic appliance and household or consumer products industries. New applications include packaging, especially medical and pharmaceutical packaging, biaxially oriented PP film, flexible film, and injection and blow moulded articles. 

The use of plastics in modern pharmaceutical packaging products is described. Aspects covered include the continual quest for an ideal material and process, properties, machinery and selection criteria (FDA approval, tamper-evident packaging, product-package compatibility, sterilisation, polymer additives, smart design and environmentally-friendly packaging). 

Another concern is loss of dissolved material from the contents of a package into its polymer walls (Roberts et al., 1979). It is important in pharmaceutical packaging (Po-lack et al., 1979) and in loss of flavor or odor compounds (Hansen and Arora, 1989), both situations where low concentrations of dissolved material may be important. 

Bio-based materials are materials that are taken from or made from natural materials in living things. Examples include packing pellets made from corn and soybeans, polylactic acid (a polymer used to make plastic packaging), and various kinds of pharmaceuticals. 

Polyethylene. The most straightforward process for the production of polymers from ethylene is that of the direct polymerization of the olefin. The polymerization process usually requires pressures and temperatures of 15,000 to 30,000 pounds per square inch and 200° to 300° C., and may be effected in either gas or liquid phase reactions (9). The polymer of molecular weight above 20,000 is the white, translucent plastic, polyethylene, widely used in electrical insulation, packaging material for foods, cosmetics and pharmaceuticals, liners for paper bags, etc. Articles molded from polyethylene are semirigid or rigid, depending on their thickness, but in thin films the material has excellent flexibility, even at relatively low temperatures. 

Due to its particularly good polymer characteristics PVC has an enormously wide spectrum of applications. From the consumption of more than 5.5 x 106 t in Western Europe (1997), 60% is in the building field, with a tendency to rise. Blow molded containers for packaging liquid products (beverages, edible oils, detergents, cosmetics and pharmaceuticals) receive special consideration, as do dishes for fatty foods (highly... 

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