Packaging applications functions

All computer systems performing regulated operations must be validated. To support computer systems validation, the applications developed using standard software packages are functionally tested (black box testing) and the installed versions recorded. 

Gnatenko, D. V., Saenko, E. L., Jesty, J., Cao, L. X., Hearing, P. and Bahou, W. F. (1999). Human factor VIII can be packaged and functionally expressed in an adeno-associated virus background Applicability to haemophilia A gene therapy. Br. J. Haematol. 104, 27-36. 

One of the first applications of biodegradable materials is based on the cooked, extruded, and expanded starch known from the food and chemical sectors (Fig. 14.23). Starch is cooked with water in the extruder and chemically modified as necessary or mixed with plasticizers, then expanded to a starch foam and dried. The extrudate is ground so that the functional properties thus created can be used in the food/chemicals sector. The foamed, cut, and dried extrudate is the end product for loose-fill packaging applications. The degree of expansion is a measure of the foam texture. It increases strongly with product temperature at the die, helped by a higher specific mechanical energy input. However, both measures increase the water-solubility of the product. 

It is generally known that only a very limited number of packaging materials such as glass or metal provide absolute protection properties concerning the penetration of chemical compounds from layers behind or from the environment. In the case of multi-layers with plastics materials as functional barriers there occurs, in most cases to a certain extent, an unavoidable mass transfer from the plastics layers into the product. This must be understood as a functional quantity which, however, must comply with food regulations. Therefore it is necessary firstly to understand functional barrier characteristics and mechanisms and, secondly, to define the functional barrier efficiency in relation to food safety and to establish appropriate test methods. This is especially important with those food packaging applications where recycled plastics are covered by plastics functional barriers. 

Oxygen barrier data for pure H40 systems and H40 network systems measured at RT and 0 and 50%RH are summarized in Table 1 which also reports Tg s and densities in the dry state. Due to the high concentration of hydroxyl functional groups in the periphery, excellent gas barrier characteristics for pure H40 are predicted. As seen in Table 1, the pure H40 at 0%RH displayed considerably better oxygen barrier characteristics than PET and comparable to those for EVOH with 48% (mol/mol) of ethylene. EVOH copolymers with low and moderate ethylene content are considered benchmark materials for packaging applications. When exposed to ambient humidity (50% RH) the barrier properties were reduced, but still better than PET. Figure 6 (a), (b), and... 

Pea is a renewable reservoir for functional macromolecules. Pea proteins or starches can be used for packaging applications, such as films, foams and controlled release systems. The functionality of the biopolymers is influenced by technological treatments and altered by physical, enzymatic or chemical modifications. This work is aimed at obtaining detailed knowledge about the structure-property relationships of pea-based biodegradable plastics. 

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