Plasticizers odor development

As a conclusion it results that neither the suspected methoxy propanol nor the MEK used as solvent could contain a high enough concentration of the off-odor-caus-ing ketone. The off-odor developed first after printing and subsequent evaporation of the solvent. Because of its relatively low solubility and good solubility in the plastic the unsaturated ketone was slowly set free during further storage of the packaging. 

Historical Perspective General Theory of Plasticization Plasticizer Compatibility Compatibility Stability Fusion Properties of Plasticizers Plasticizer Concentration Effects Heat Stability Odor Development... 

Vinyl stabilizers can aggravate oxidation or Inhibit it. The same is true for pigments, some of which are prooxidants while others are antioxidants. To assure satisfactory odor in use, a chemically stable plasticizer should be selected the vinyl composition should be well stabilized during processing and antioxidants added to the formulation, if not already present in the "stabilizer package" used. To assess potential odor development, it is prudent to test every new vinyl formulation by heating in a closed bottle at 50 C for several days. 

MAJOR USES Manufacture of other chemicals including benzyl compounds, synthetic tannins, dyes, perfumes, phamiaceutical products, fungicides, pesticides used in manufacturing process of photographic developer, penicillin precursors, rubber accelerators, lubricants, plastics, odorants, plasticizers. 

As mentioned above, prolonged exposure of the plasticizer to heat, affects its physical and chemical properties. This is also important for storage of the plasticizer in drums. If drums are stored exposed to direct sunlight the color of plasticizer is likely to degrade and an unpleasant odor develops which then affects the quality of the final product. 

Abstract Mate recognition is an essential component of successful reproductive behavior, and in rodent species, is primarily guided by the perception of social odors in the environment. Importantly, there is substantial evidence that species or sexual odor preferences may be regulated by early olfactory experience, although considerable variability in the plasticity of these behaviors has been observed. The current chapter summarizes what is known regarding the role of early olfactory experience in the development of adult odor preferences, synthesizing data across species, sex, and behavioral paradigms. 

Taken together, this body of work demonstrates that adult behavioral responses to social odors are shaped by early olfactory experience. Indeed, heterospecific or artificial odor cues associated with the rearing environment acquire attractive properties that can last into adulthood in many rodent species. Furthermore, early experience with opposite-sex odors appears to be critical for the normal development of appropriate behavioral responses to sexual odors in mice and hamsters. Importantly, the behavioral plasticity observed using these different experimental approaches may all be mediated by a classical conditioning model of olfactory learning. The experience-dependent development of odor preference in rodents therefore provides a powerful model for understanding how the olfactory system recognizes and learns the salience of social odors, a function that is critical for the appropriate expression of reproductive behavior. 

Phthalates were first introduced in the 1920s and quickly replaced the volatile and odorous camphor. In the earliest 1930s, the commercial availability of PVC and the development of DEHP caused the boom of the plasticizer PVC industry. 

Benzene is a volatile, colorless, highly flammable liquid that is consumed as a raw material for the manufacture of phenolic and polyester resins, polystyrene plastics, alkylbenzene surfactants, chlorobenzenes, insecticides, and dyes. It is hazardous both for its ignitability and toxicity (exposure to benzene causes blood abnormalities that may develop into leukemia). Naphthalene is the simplest member of a large number of multicychc aromatic hydrocarbons having two or more fused rings. It is a volatile white crystalline solid with a characteristic odor and has been used to make mothballs. The most important of the many chemical derivatives made from naphthalene is phthalic anhydride, from which phthalate ester plasticizers are synthesized. 

Uses Benzyl chloride is a colorless liquid with an irritating odor. It is used in the manufacture of plastics, dyes, synthetic tannins, perfumes, resins, gasoline additives, germicides, perfumes, photographic developers, rubbers, wetting agents, drugs, and pharmaceuticals. It also is used in production of benzal chloride, benzyl alcohol, and benzaldehyde.116... 

Odor compounds may also be released from the plastic materials used in cars. The variety of plastics and possible chemical compounds is broad, which makes the identification of odor causing compounds an extremely comphcated task. An effective and rapid screening of VOCs and semi-VOCs from materials used in automobiles was developed by utihzing the SPME technique [28]. The low molecular weight compoimds extracted from five different automobile materials included different benzene derivatives, aldehydes, esters, biphenyls, phthalates, butylated hydroxytoluene, phenols, alcohols, styrene, triethylene-diamine, carboxylic acids and ketones. A considerable munber of VOCs and semi-VOCs were detected, indicating that more attention should be paid to the selection of materials and additives for automotive parts. 

---