Plastic bottle

Abstract: Observers of deviant social behavior sometimes communicate disapproval directly or indirectly to the perpetrator of a deviant act. This reaction has been termed ‘social control’. Three field studies were conducted to explore the influence of the number of bystander-observers on the likelihood of social control. We predicted that the presence of others would inhibit people’s tendency to communicate their disapproval to the deviant but only if personal implication was low. In the first study, we measured participants’ perceptions of two fictive situations, one in which a deviant draws graffiti in an elevator of a shopping center and one in which a deviant litters in a small neighborhood park by throwing a plastic bottle in the bushes. As expected, participants considered both behaviors to be equally counternormative but felt personally more implicated by the littering behavior in the park. In Studies 2 and 3, the two situations were enacted with confederates of the experimenter. Nao¨ve bystanders served as participants, and social control was the primary dependent variable. Consistent with our hypothesis, we found evidence for a bystander effect in the low personal implication situation (‘graffiti in the elevator’) but not in the high personal implication situation (‘littering in park’). These results make clear that perceived personal implication moderates the extent to which people are inhibited by the presence of others when they decide whether they should exert social control or not. Copyright # 2002 John Wiley & Sons, Ltd. It is generally agreed that social norms are powerful determinants of human behavior (Asch, 1951; Cialdini, Kallgren, & Reno, 1991; Newcomb, 1961; Schachter & Singer, 1962; Schwartz, 1977; Sherif, 1936; Sherif, Harvey, White, Hood, & Sherif, 1961). Social norms are specific to particular groups, as each group creates its own standards for what attitudes or behaviors are acceptable and desirable. What is considered normative in one group may be seen as being a counternormative (deviant) behavior in another group. For example, in France it is considered polite to fill up a guest’s wine glass when it is still half full. A host who lets his or her guests empty their wine glasses is considered inattentive. In Germany, on the other hand, it is expected that hosts pour more wine only when the guest’s wine glass is empty. Filling up a wine glass that is still half full would be considered

Abstract: Chemical upcycling of waste polyolefins via hydrogenolysis offers unique opportunities for selective depolymerization compared to high temperature thermal deconstruction. Here, we demonstrate the hydrogenolysis of polyethylene into liquid alkanes under mild conditions using ruthenium nanoparticles supported on carbon (Ru/C). Reactivity studies on a model n-octadecane substrate showed that Ru/C catalysts are highly active and selective for the hydrogenolysis of C(sp3)-C(sp3) bonds at temperatures ranging from 200 to 250 °C. Under optimal conditions of 200 °C in 20 bar H2, polyethylene (average Mw ∼ 4000 Da) was converted into liquid n-alkanes with yields of up to 45% by mass after 16 h using a 5 wt % Ru/C catalyst with the remaining products comprising light alkane gases (C1-C6). At 250 °C, nearly stoichiometric yields of CH4 were obtained from polyethylene over the catalyst. The hydrogenolysis of long chain, low-density polyethylene (LDPE) and a postconsumer LDPE plastic bottle to produce C7-C45 alkanes was also achieved over Ru/C, demonstrating the feasibility of this reaction for the valorization of realistic postconsumer plastic waste. By identifying Ru-based catalysts as a class of active materials for the hydrogenolysis of polyethylene, this study elucidates promising avenues for the valorization of plastic waste under mild conditions.

Abstract: Disposal of plastic waste has become a widely discussed issue, due to the potential environmental impact of improper waste disposal. Polyethylene terephthalate (PET) packaging accounted for 44.7% of single-serve beverage packaging in the US in 2021, and 12% of global solid waste. A strategic solution is needed to manage plastic packaging solid waste. Major beverage manufacturers have pledged to reduce their environmental footprint by taking steps towards a sustainable future. The PET bottle has several properties that make it an environmentally friendly choice. The PET bottle has good barrier properties as its single-layer, mono-material composition allows it to be more easily recycled. Compared to glass, the PET bottle is lightweight and has a lower carbon footprint in production and transportation. With modern advancements to decontamination processes in the recycling of post-consumer recycled PET (rPET or PCR), it has become a safe material for reuse as beverage packaging. It has been 30 years since the FDA first began certifying PCR PET production processes as compliant for production of food contact PCR PET, for application within the United States. This article provides an overview of PET bottle-to-bottle recycling and guidance for beverage manufacturers looking to advance goals for sustainability.