Plastic packaging, analysis

Contaminants in recycled plastic packaging waste (HDPE, PP) were identified by MAE followed by GC-MS analysis [290]. Fragrance and flavour constituents from first usage were detected. Recycled material also contained aliphatic hydrocarbons, branched alkanes and alkenes, which are also found in virgin resins at similar concentration levels. Moreover, aromatic hydrocarbons, probably derived from additives, were found. Postconsumer PET was also analysed by Soxhlet extraction and GC-MS most of the extracted compounds (30) were thermally degraded products of additives and polymers, whereas only a few derived from the original contents... 

Food deterioration can occur by means other than transport of gases into the food container or water into or out of the container. The loss of food characteristics in plastics packaging may also occur from direct interaction of the food with the polymer. The measurement of these types of transport is often termed organoleptic analysis because they may involve human taste tests. The tainting of food by transport of substances from the polymer into the food is termed migration. The loss of flavor constituents from the food into the polymer is termed scalping (32). Water content can affect these transport characteristics as well. 

The fact that Raman measurements can usually be made through glass and plastic packaging, eliminating the need to prepare samples prior to analysis, makes Raman spectroscopy very attractive for forensic science. The availability of commercial portable instramentation and extended fiber optic probes makes Raman suitable for on-site forensic use, minimizing the risk of exposure of investigating personnel to potentially hazardous chemicals. Eor identification of explosives the SERS method has proved to be very useful. A tiny amount of explosive, diluted... 

No. 273 and No. 301 are the specification for plastics used in medical practice, in Japan. These testing items consist of extraction test, heavy metal analysis, acute toxicity test, hemolysis test and pyrogen test. All the results of the examination passed the regulations and indicate that the 1, 2-PBD is safe enough to be used as a plastic packaging for foods. In the case of acute toxicity, the number of deaths of the mice was zero. Further, it is assumed that the 1, 2-PBD has the possibi-bility to be applied to the medical plastics field. 

Figure 13.36. Cost-benefit analysis for mechanical recycling of plastics packaging from households in Austria 1996 (/t collected material [21]).

Franklin Associates, Ltd. Impact of plastics packaging on life cycle energy consumption greenhouse gas emissions in the United States and substitution analysis. Prairie Village Franklin Associates, Ltd 2014. 

The area of flavor and aroma barrier is receiving growing attention in the field of plastics packaging. The permeation of flavors is difficult to measure quantitatively because they contain many components. Many times, only a simple component of a flavor is measured if a quantitative value must be determined. Gas chromatography and mass spectrophotometric (GC/MS) techniques have been developed that allow the analysis of complex flavors. However, in most cases, the use of organoleptic testing provides reliable and pertinent data at a greatly reduced cost. 

Plastic products are prepared by addition of plasticisers. Esters of phthalic, of phosphoric and of aliphatic dicarboxyhc acids, epoxides and some high molecular weight compounds are especially suitable. Since some of these substances are highly toxic, a sensitive chemical method of detection was desirable. GC analysis is rendered difficult by the high boiling points of the plasticisers but identification with the help of TLC is most successful. Plasticisers authorised in the USA for use in plastic package... 

Bob A. Howell, PhD, is a Professor in the Department of Chemistry at Central Michigan University in Mount Pleasant, Michigan. He received his PhD in physical organic chemistry from Ohio University in 1971. His research interests include flame-retardants for polymeric materials, new polymeric fuel-cell membranes, polymerization techniques, thermal methods of analysis, polymer-supported organoplatinum antitumor agents, barrier plastic packaging, bioplastics, and polymers from renewable sources. 

The manufacturer of plastic packaging has to know in what amounts an additive migrates into food this amount must be determined by simulating all conditions in which it is used (temperature, contact time, food simulants). The food simulants used are distilled water, aqueous acetic acid, aqueous ethanol, and natural fats or oils 95% ethanol and ethyl acetate are recommended as fat simulants for PO. Only 10, 50, or 100 ppb (parts per billion) of additives are tolerated in food. Numerous methods of additive analysis have been developed [1,60]. 

Dynamic differential thermal analysis is used to measure the phase transitions of the polymer. IR is used to determine the degree of unsaturation in the polymer. Monitoring of the purity and raw is done commercially using gas phase chromatography for fractionization and R1 with UV absorption at 260 nanometers for polystyrene identification and measurement Polystyrene is one of the most widely used plastics because of fabrication ease and the wide spectrum of properties possible. Industries using styrene-based plastics are packaging, appliance, construction, automotive, radio and television, furniture, toy, houseware and baggage. Styrene is also used by the military as a binder in expls and rocket propints... 

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