During the past 50 years, polymers have essentially changed human life, and the plastics industry has developed materials increasingly adapted to specific uses.1 The processing, durability, and end-use response of plastic items result from an adequate and precise combination of the desired polymer and additives. Additives such as lubricants, plasticizers, antioxidants, light stabilizers, colorants and dyestuffs, antistatic agents, surfactants, and preservatives are all commonly encountered in various polymer formulations, including synthetic polymers, biopolymers, composites, and biocomposites.2-92, 3, 4, 5, 6, 7, 8, 9

There are hundreds of chemical compounds that are currently used as additives in polymer formulations. Table 1 summarizes some of the most common among them. Of all additives used to modify polymer properties, plasticizers have gained industrial importance because they reduce melt viscosity, lower the viscosity modulus, and increase the flexibility and workability of the polymeric materials.10 Lubricants increase the overall rate of processing or improve the release properties during processing and molding operations.11 Antioxidants, in particular hindered phenols (Table 1), which can be natural, as in the case of -tocopherol,12 preserve polymer chemical and physical-mechanical properties both during processing and under use conditions.13 Natural antioxidants are used to replace synthetic ones mainly in biopolymers and biocomposites to render them completely compatible with different biologically active environments (e.g., natural environments, human body). Light stabilizers have the ability to reduce photo-oxidation and protect polymers from UV damage. In general, they respond to the structure of hindered amines, and are known as hindered amine light stabilizers (HALSs).5 One strategy to prevent bacterial attachment and proliferation on a polymer material is to kill the micro-organisms in contact with the substratum, which has led to the investigation of polymeric materials that contain immobilized biocides.14 Nowadays, and in response to the fact that polymers are currently exposed to outdoor environments, additives with the capacity of preventing or reducing biological attack, e.g., antifungals and biocides, are also included in polymer formulations.15 In contrast, aromatic ketones are being used to modify stable polymers commonly used in the manufacture of packaging materials, such as polystyrene and poly (vinylchloride) (PVC), in an attempt to make them degradable in natural environments.16 Flame retardants are a class of materials that are compounded into plastics to provide certain defined reactions during combustion.17

Table 1 Some common polymer additives

Additive	Chemical name	Acronym/commercial name
Lubricants	Stearic acid	SA
	Stearamide	STA
	N,N-9-Ethylenebistearamide	EBS
Plasticizers	Di(2-ethylhexyl)phthalate	DEHP; DOP
	Dibutylphthalate	DBP
	Di(2-ethylhexyl)adipate	DOA
	Trioctyltrimellitate	TOTM
	Triethyl citrate	TEC
	Dipropylene glycol dibenzoate	Benzoflex 9-88®
Antioxidants	Di-t-butyl-p-cresol	Bisphenol A®
	Dioctadecyl-(3,5-di-t-butyl-4-hydroxybenzyl)phosphate	Irganox ®1093
	2,2'-Methylene-bis-(4-methyl-6-t-butylphenol)	Cyanox 2246®
	Octadecyl-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate	Irganox ®1076
	-Tocopherol	Vitamin E
Light stabilizers	2-(2-Hydroxy-3,5-di-t-amylphenyl)-2H-benzotriazole	Tinuvin 328®
	2-Hydroxy-4-n-octoxybenzophenone	Chimassorb 81®
	Poly6-[(1,1,3,3-tetramethylbutyl)-imino]-1,3,5-triazine-2,4-diyl-(2,2,6,6-tetramethylpiperidyl)-imino-hexamethylene-[4-(2,2,6,6-tetramethylpiperidyl)]-imino	Chimassorb 944®
Organic flame retardants	Tetrabromobisphenol A	TBBA
	Hexabromocyclododecane	HBCD
	1,2,3,4,7,8,9,10,13,13,14,14-Dodecachloro-1,4,4,5,6,6,7,10,10,11,12,12a-dodecahydro-1,4,7,10-dimethanodibenzo[,ε]-cyclo-octene	Dechlorane Plus®

The identification and eventual determination of polymer additives is an important issue in many fields.18 In the area of packaging materials, additive migration from materials in contact with food may have potential toxic effects in humans.3 In biomedical applications, plasticizers present in polymers [e.g., diethylhexylphthalate (DEHP) in PVC] can readily leach into the liquids passing through them, particularly lipid-containing fluids, e.g., blood. There is great concern about the toxicity of DEHP, especially for risk groups such as patients on hemodialysis.19 International regulations require that pharmaceutical, biomedical, cosmetic, and packaging materials should not interact physically or chemically with their contents or environments. Therefore, the possible release of polymer additives by plastic items should be monitored and minimized. Chromatographic techniques, either on their own or in conjunction with powerful analytical techniques, in particular mass spectrometry (MS), have shown great potential in the identification and eventual determination of many of these compounds. As pointed out above, it is evident that the development of new reliable and rapid analysis methods for polymer additives is a challenging task for several reasons: quality control; additive depletion/stability during processing and lifetime; litigation; migration studies; contamination; government regulations; and development of new materials.19