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A bio-based polymeric ink for stereolithography developed through a two-step solvent-free process is herein proposed. Specifically, low-molecular-weight poly(hydroxybutyrate) (PHB)-diol oligomers are prepared via molten transesterification of bacterial PHB with 1,4-butanediol. Transesterification conditions such as diol concentration, catalyst amount, and reaction time are studied for optimizing the final oligomers' molecular weight and structural features. In the second step, the oligomeric hydroxyl terminals are converted into methacrylate moieties through a solvent-free end-capping reaction and diluted in propylene carbonate in order to obtain a photo-polymerizable ink with suitable viscosity. The ink is UV-cured, and the obtained material properties are investigated by FT-IR and differential scanning calorimetry measurements. The proposed method provides a valuable and environmentally friendly alternative to currently available synthetic routes, overcoming their typical disadvantages related to the used solvents and harsh conditions. Moreover, it opens up a sustainable route for converting polyesters into functionalized oligomeric derivatives, which can potentially find application in 3D printing of customized biomedical devices.
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Hidroxibutiratos/síntese química , Poliésteres/síntese química , Resinas Sintéticas/química , Estereolitografia , Hidroxibutiratos/química , Estrutura Molecular , Processos Fotoquímicos , Poliésteres/químicaRESUMO
OBJECTIVE: To evaluate the effect of a newly acquired spinal cord injury (SCI) by identifying profiles of psychological adaptation outcomes at discharge from inpatient rehabilitation, using several outcome measures in parallel and to examine biopsychosocial factors associated with profile membership. DESIGN: Cross-sectional analysis of data from the Swiss Spinal Cord Injury inception cohort study. SETTING: Inpatient rehabilitation. PARTICIPANTS: Individuals 16 years old or older with recently diagnosed SCI who finished clinical rehabilitation in 1 of the 4 major national rehabilitation centers (N=370). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Life satisfaction, general distress, and symptoms of depression and anxiety were assessed using a single item from the International SCI Quality of Life Basic Data Set, the Distress Thermometer, and the Hospital Anxiety and Depression Scale respectively. RESULTS: Using latent profile analysis, 4 profiles of psychological adaptation outcomes were identified displaying different levels of impact, ranging from Minimal to Severe. Regarding covariates associated with profile membership, higher optimism, purpose in life, and self-efficacy indicated a higher probability of having a Minimal impact profile. Additionally, males, individuals with better functional independence, and those with an absence of pain were more likely to show a Minimal impact profile. CONCLUSIONS: Among the participants, 70% showed Minimal or Low impact profiles. Our findings support that individuals can show positive responses across several outcome measures even at an early time after the injury onset (eg, at discharge from inpatient rehabilitation). Moreover, our results indicate that beyond functional independence, improvement, and pain management, a rehabilitation process that strengthens psychological resources might contribute to better adaptation outcomes.
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Adaptação Psicológica , Alta do Paciente , Traumatismos da Medula Espinal/psicologia , Traumatismos da Medula Espinal/reabilitação , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Medição da Dor , Escalas de Graduação Psiquiátrica , Qualidade de Vida , Centros de Reabilitação , Autoeficácia , SuíçaRESUMO
OBJECTIVES: In 2015 we identified three profiles of adaptation following spousal bereavement: Vulnerables; Copers and Resilients (Spahni, Morselli, Perrig-Chiello, & Bennett, 2015). However, adaptation to spousal bereavement is a dynamic process. Thus, we examine the trajectories of the same participants longitudinally over two years. We identify the stability and change in profiles of adaptation to widowhood; probability of stability and change; factors that influence trajectories in profile membership. METHODS: Data stem from a longitudinal questionnaire study of 309 older widowed people. The questionnaire included five measures of well-being, serving as the dependent variables of this analysis, and measures of personal resources and contextual factors, including social support, marital happiness, psychological resilience, and demography. Data was analysed using latent transition analysis of the variables loneliness, hopelessness, depressive symptoms, life satisfaction, and subjective health. RESULTS: The analysis replicated the three Wave 1 profiles as the best theoretical fit: Vulnerables; Copers; and Resilients. Stability was most common, but some participants moved to more or less adaptive profiles, the former being more frequent. Younger age, longer time since widowhood, new life perspectives facilitated adaptation. Those transitioning to less adaptive profiles were more likely to be women and older. DISCUSSION: The path to adaptation was not linear. Many of the explanatory variables contributed both to positive and negative adaptation. These include previous caring experience, education, psychological resilience and personal strength. This suggests these explanatory variables do not act in isolation but are likely to interact with each other, and with other, yet not measured, factors.
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Luto , Resiliência Psicológica , Viuvez , Adaptação Psicológica , Feminino , Humanos , SolidãoRESUMO
Background:One of the possible negative consequences of sexting is the non-consensual sharing of received-intimate content. This study aimed to determine the characteristics and motives of youths who shared received-intimate images without consent. Methods: Data were obtained from a self-administrated Swiss survey on sexual behaviours among young adults (aged 24-26 years). Out of the 7142 participants, 5175 responded to the question 'Have you ever shared (forwarding or showing) a sexy photograph/video of someone else (known or unknown) without consent'?; 85% had never shared (Never), 6% had shared once (Once) and 9% had shared several times (Several). Data are presented as relative risk ratios with 95% confidence intervals. Results: Participants who had shared received-intimate content without consent had higher odds of being male [2.73 (2.14-3.47)], foreign-born [1.45 (1.04-2.03)], reporting a non-heterosexual orientation [1.46 (1.10-1.93)], having sent one's own intimate image [1.76 (1.32-2.34)] and receiving a shared-intimate image of someone unknown [4.56 (3.28-6.36)] or known [2.76 (1.52-5.01)] compared with participants who had never shared. The main reported motivations were for fun (62%), showing off (30%) and failure to realise what they were doing (9%). Conclusions: Given the reported motivations, it appears crucial to remind youths of the seriousness of non-consensual sharing. Although females may also be perpetrators, the behaviour was more prevalent among males. Prevention and education need to consider a broad range of young people in their scenarios. Even if a particular focus on understanding and preventing males' perpetration must be considered, overall perpetration, including female's, must be discussed.
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Background The aims of this research were to determine personal differences depending on the reason for regretting or not first vaginal intercourse and its effects on sexual behaviour later on among young adults, and to assess the association between reasons for engaging in first vaginal intercourse and regretting it. METHODS: Data were drawn from the 2017 Swiss national survey on youth sexual behaviours among young adults (mean age 26 years) living in Switzerland. Out of the 7142 participants, 4793 (51% females) answered the question 'Looking back now to the first time you had vaginal intercourse, do you think that ' with five possible answers: (1) I should not have done it (6.7%); (2) I should have waited longer (7.7%); (3) I should have done it earlier (7.4%); (4) It was about the right time (67.9%); and (5) I don't know (10.3%). The five groups were compared on sociodemographic and sex behaviour-related variables, analysed separately by gender. RESULTS: One-third of participants regretted their first experience. In the multivariate analysis, compared with the 'right time' group, all other groups were more likely to find their first experience unpleasant and to have done it with a casual partner. Those in the 'I should not have done it' and 'I should have waited longer' groups were also more likely to have done it because of external pressure, especially among females. CONCLUSIONS: The study results underline the significance to choose the right time and the right partner for first vaginal intercourse and the importance of including partner respect and avoiding external pressure as part of sexual education.
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Coito/psicologia , Emoções , Comportamento Sexual/psicologia , Adulto , Feminino , Humanos , Masculino , Inquéritos e Questionários , SuíçaRESUMO
A new, facile and low-sample consuming technique for the determination of hydroxyl values (OHVs) in poly(hydroxyalkanoate)s (PHAs) is herein presented. After a fast, uncatalyzed and non-destructive trifluoroacetylation of all PHA hydroxyl groups, OHVs are calculated through 19F-NMR measurements, comparing integral values of the only two signals in the spectra: the fluorinated hydroxyl groups and the internal standard (trifluorotoluene) signals. Furthermore, the combined ex situ functionalization with a simple workup of the fluorinated polymer allowed to obtain spectra with an improved signal/noise ratio and short acquisition time if compared to 1H-NMR-based methods. The results obtained by 19F-NMR measurements are then validated by the established standard method based on acid/base titration and the 1H-NMR-based method. The proposed approach shows to be valuable not only for low molecular weight PHAs, but also for high molecular weight samples, which typically cannot be analysed by conventional 1H-NMR-based methods due to the very low concentration of hydroxyl terminal groups. Thanks to the observed high reliability, the method was also successfully applied to evaluate the OHVs of various commercial hydroxyl terminated polymers with different molecular weights in order to further show its wide applicability.
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BACKGROUND: Critical events in the second half of life, such as divorce, pose a significant threat to well-being. Individuals undergoing divorce often experience feelings of social loneliness and may benefit differently from available resources depending on how much time has passed since the event. Personality traits have been found to be related to adaptation, with particularly strong effects immediately after the critical event. Other resources, such as identity-stabilizing mechanisms (i.e., valued social groups and self-continuity), may play a role only later in adaptation. However, little is known about the benefits of these resources and their potentially time-dependent effects on social loneliness when one is overcoming later-life divorce. OBJECTIVES: This study investigates the role of psychological (e.g., personality, self-continuity, multiple important group memberships) and social resources (e.g., new partner, having someone to help deal with divorce) for social loneliness in two post-divorce phases, using a married group as the reference, controlling for sociodemographic aspects and health. METHODS: A representative sample of 850 divorced (aged 40-79 years) and 869 married individuals (aged 40-78 years) living in Switzerland were compared, using multiple regression analyses. RESULTS: Differential predictive patterns for social loneliness between the two divorced groups and the married group were observed. For the short-term divorced (up to 2 years after divorce), higher extroversion and agreeableness and lower neuroticism were associated with lower levels of loneliness. For the long-term divorced (2-5 years after divorce) and for those who remained married, extroversion was similarly important for loneliness. Additionally, higher levels of self-continuity and multiple group memberships predicted lower loneliness, but the short-term divorced did not benefit from them. Having someone to help overcome the divorce benefited members of both divorced groups. A new partner was related to less loneliness, but only in the long-term divorced group. CONCLUSIONS: Our findings demonstrate that the effects of psychological and social resources on social loneliness vary by adaptation phase. Although extroversion is beneficial for all divorced and married individuals, other personality traits play a more decisive role in the initial adaptation phase. Identity-promoting resources (i.e., multiple group memberships, perceived self-continuity) are beneficial only later in the adaptation process. To be successful, professional interventions must be tailored as needed.
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Divórcio/psicologia , Solidão/psicologia , Adaptação Psicológica , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Geriatria , Humanos , Masculino , Casamento/psicologia , Pessoa de Meia-Idade , Personalidade , Meio Social , Estresse Psicológico , Suíça , Fatores de TempoRESUMO
Following the status-anxiety hypothesis, the psychological consequences of income inequality should be particularly severe for economically vulnerable individuals. Oddly, however, income inequality is often found to affect vulnerable low-income and advantaged high-income groups equally. We argue that economic vulnerability is better captured by a financial-scarcity measure and hypothesize that income inequality primarily impairs the psychological health of people facing scarcity. First, repeated cross-sectional international data (from the World Values Survey: 146,034 participants; 105 country waves) revealed that the within-country effect of national income inequality on feelings of unhappiness was limited to individuals facing scarcity (≈25% of the World Values Survey population). Second, longitudinal national data (Swiss Household Panel: 14,790 participants; 15,595 municipality years) revealed that the within-life-course effect of local income inequality on psychological health problems was also limited to these individuals (< 10% of the Swiss population). Income inequality by itself may not be a problem for psychological health but, rather, may be a catalyst for the consequences of financial scarcity.
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BACKGROUND: Marital dissolution is known to be among the most stressful life events with long-reaching negative consequences on individuals' lives. A limitation in research to date is that most studies have focused on the impact of marital disruption on well-being outcomes in younger adults. Furthermore, although population-based studies on divorce document a broad range of negative effects, more fine-grained analyses reveal a large heterogeneity in people's adjustment, which is still not well understood. OBJECTIVE: The aim was to explore trajectories of psychological adaptation to marital breakup after a long-term marriage, and to examine variables accounting for recovery or chronicity in terms of intrapersonal resources (personality, trait resilience, and personal growth), relationship variables (satisfaction with ex-relationship, length of marriage, and time since divorce), and sociodemographic variables (age, gender, and financial situation). METHODS: Latent transition analysis is used to examine the course of psychological adaptation (i.e., depressive symptoms, life satisfaction, hopelessness, mourning, and subjective health) to divorce over 2 years among 5 profiles of 308 divorcees (mean age: 55.6 years; average duration of former marriage: 23.62 years). We present two larger groups of individuals, one of which adapted very well ('resilients', 29%) and the other quite well ('average copers', 49%), as well as three groups with major difficulties ('vulnerables', 6%; 'malcontents', 12%, and 'resigned', 4%). In a second step, the differences between transition patterns were explored on the basis of the distal variables (i.e., intrapersonal resources, relationship variables, and sociodemographics). RESULTS: Although the probability of upward changes was higher for those individuals with lower adaptation at time point 1, only a small number of individuals made an upward change from the maladapted to the well-adapted groups throughout the 2 years. The groups of copers and resilients remained stable in their psychological adaptation. The most consistent results related to upward changes were intrapersonal resources, namely the NEO personality traits and trait resilience. CONCLUSION: The majority of individuals divorcing after a long-term marriage adapt successfully over time. Adaptation trajectories depend primarily on intrapersonal resources. However, a minority of divorcees exhibit enduring difficulties. Knowledge about the diversity of these trajectories of vulnerability could be of great help for designing psychological interventions to better tackle this critical life event.
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Adaptação Psicológica , Divórcio/psicologia , Idoso , Feminino , Humanos , Acontecimentos que Mudam a Vida , Masculino , Casamento/psicologia , Pessoa de Meia-Idade , Técnicas Psicológicas , Fatores Socioeconômicos , Estresse Psicológico/diagnóstico , Estresse Psicológico/reabilitação , Suíça , TempoRESUMO
BACKGROUND: While the negative effects of spousal bereavement on well-being are well documented in empirical research, the large individual differences in psychological adaptation are still not well understood. OBJECTIVE: This contribution aims to identify patterns of psychological adaptation to spousal loss in old age and to shed light on the role of intra- and interpersonal resources and contextual factors as discriminant variables among these patterns. METHODS: The data stem from a cross-sectional questionnaire study of 402 widowed individuals (228 women, 174 men) aged between 60 and 89 years (mean age 74.41 years), who lost their partner within the last 5 years, and 618 married individuals, who served as controls (312 women, 306 men; mean age 73.82 years). RESULTS: The exploratory latent profile analysis of the well-being outcomes of depressive symptoms, hopelessness, loneliness, life satisfaction and subjective health revealed three different groups in the widowed sample: 'resilients' (54% of the sample), 'copers' (39%) and 'vulnerables' (7%). The most important variables for group allocation were intrapersonal resources - psychological resilience and the Big Five personality traits - but also the quality of the former relationship and how the loss was experienced. CONCLUSION: Successful adaptation to spousal loss is primarily associated with high scores in psychological resilience and extraversion and low scores in neuroticism. Our results shed light on the variability in psychological adaptation and underline the important role of intrapersonal resources in facing spousal loss in old age.
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Adaptação Psicológica , Envelhecimento/psicologia , Luto , Viuvez/psicologia , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Psicológicos , Personalidade , Resiliência Psicológica , Apoio Social , Inquéritos e QuestionáriosRESUMO
In Crimes of obedience, Kelman and Hamilton argue that societies can be protected by the degeneration of authority only when citizenship is based on a strong values orientation. This reference to values may be the weakest point in their theory because they do not explicitly define these values. Nevertheless, their empirical findings suggest that the authors are referring to specific democratic principles and universal values (e.g., equality, fairness, harmlessness). In this article, a composite index known as the value-oriented citizenship (VOC) index is introduced and empirically analysed. The results confirm that the VOC index discriminates between people who relate to authority based on values rather than based on their role or on rules in general. The article discusses the utility of the VOC index to develop Kelman and Hamilton's framework further empirically as well as its implications for the analysis of the relationship between individuals and authority.
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Comportamento Cooperativo , Sistemas Políticos , Controle Social Formal , Valores Sociais , Adolescente , Adulto , Idoso , Democracia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Justiça Social , Adulto JovemRESUMO
Arab nations are decades behind many other previously colonized nations in developing stronger economies, more democratic institutions, and more autonomy and self-government, in part as a result of external interference. The year 2011 brought the potential for greater Arab autonomy through popular uprisings against autocratic governments in Tunisia, Egypt, and Yemen, and through the Palestinian request for state recognition by the United Nations. We examined the psychology of support for Arab ascendancy among adults in 14 nations in the Balkans, the Middle East, Asia, Oceania, Europe, and North America. We predicted and found that people low on social dominance orientation endorsed forming an independent Palestinian state and desired that the Arab uprisings succeed. Rejection of ideologies that legitimize outside interference with Arabs mediated this support. Measures and model results were robust across world regions. We discuss theoretical implications regarding the advent of new ideologies and extending social dominance theory to address international relations.
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Árabes/legislação & jurisprudência , Política , Predomínio Social , Adolescente , Adulto , Idoso , Ásia , Europa (Continente) , Feminino , Humanos , Israel , Masculino , Pessoa de Meia-Idade , Nova Zelândia , Estados Unidos , Adulto JovemRESUMO
The onset of a chronic physical health condition (CHC) can highly impact individuals' well-being and mental health. Social support has been shown to help people rebound after the onset of a CHC. Nonetheless, little is known about the longitudinal pattern of social support and its reciprocal association with mental health in CHC. This study aimed to illustrate the longitudinal pattern of perceived social support and to examine the reciprocal association between perceived social support and psychological distress across 6 years. Two random intercept cross-lagged panel models were conducted, one for emotional and one for practical support, using yearly assessments of 582 Swiss Household Panel's participants reporting a CHC. A reciprocal association was found, with psychological distress 1 year after the onset being linked to less emotional support in the following year and vice versa, more emotional support being linked to less psychological distress the following year. A unidirectional association was found for practical support, with more psychological distress 1 year before the CHC onset being linked to more practical support at the onset year. This study underlines the importance of involving the social environment of individuals living with a CHC, especially around the first year after the onset.
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Angústia Psicológica , Apoio Social , Humanos , Saúde Mental , Estresse Psicológico/psicologia , Meio Social , Nonoxinol , Doença CrônicaRESUMO
OBJECTIVE: This study aims to explore the psychosocial factors which influenced the undergoing of prenatal genetic testing (PGT) in a sample of pregnant women. METHOD: An online questionnaire was emailed to a convenient sample of 105 pregnant women, recruited from among those attending two antenatal education programmes and via snowball sampling. RESULTS: A minority of respondents underwent chorionic villous sampling and amniocentesis (12 and 11, respectively). Advanced maternal age was related to undertaking PGT. The path analysis model (χ(2) (16, N = 97) = 19.01, ns; TLI = 0.95; RMSEA = 0.04; WRMR = 0.64) confirmed that three dimensions, namely having a more supporting attitude towards PGT (ß = 0.54, p < 0.001), perceiving PGT as reliable (ß = 0.29, p < 0.05) and the request for more scientific information (ß = 0.22, p < 0.01), related to test uptaking. CONCLUSION: Empirical researches investigating pregnant women's beliefs and attitudes relating to actual test uptake could help genetic counsellors and policy makers to better understand their client's profile in relation to the determining factors affecting the undertaking of PGT.
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Testes Genéticos , Conhecimentos, Atitudes e Prática em Saúde , Diagnóstico Pré-Natal/psicologia , Adulto , Cultura , Feminino , Testes Genéticos/estatística & dados numéricos , Humanos , Internet , Idade Materna , Projetos Piloto , Gravidez , Diagnóstico Pré-Natal/métodos , Diagnóstico Pré-Natal/estatística & dados numéricos , Psicologia , Inquéritos e Questionários , Adulto JovemRESUMO
Although daily hassles have been of interest since the 1980s, only a few tools have been developed to assess them. Most of them are checklists or open-ended questions that are demanding for participants in panel surveys. Therefore, to facilitate daily hassles integration into large surveys, the aim of this study was to present a new tool assessing daily hassles, the LIVES-Daily Hassles Scale (LIVES-DHS), and to examine its relation to life satisfaction, in a sample of 1,170 French- and German-speaking adults living in Switzerland. In a first random subsample, we conducted a principal axis factor analysis, and the results suggested a five-factor solution. Furthermore, we conducted a confirmatory factor analysis on a second random subsample, and it supported the hierarchical factor structure of the scale. The LIVES-DHS consists of 18 items represented by five factors that describe five sources of daily hassles: financial, physical, relational, environmental, and professional. The bivariate correlations showed that the LIVES-DHS could differentiate the concept of daily hassles from associated concepts. Finally, the hierarchical regression showed that daily hassles negatively predicted life satisfaction and added a significant incremental variance beyond that accounted for by age, gender, household income, education level, and personality traits.
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Satisfação Pessoal , Estresse Psicológico , Adulto , Humanos , Inquéritos e Questionários , SuíçaRESUMO
Fully biobased and biodegradable materials have attracted a growing interest in the food packaging sector as they can help to reduce the negative impact of fossil-based plastics on the environment. Moreover, the addition of functionalities to these materials by introducing active molecules has become an essential requirement to create modern packaging able to extend food's shelf-life while informing the consumer about food quality and freshness. In this study, we present an innovative bioplastic formulation for food packaging based on poly(hydroxybutyrate-co-valerate) (PHBV) and tannins as multifunctional additives. As a proof of concept, PHBV/tannin films were prepared by solvent casting, increasing the tannin content from 1 to 10 per hundred of resin (phr). Formic acid was used to reach a homogeneous distribution of the hydrophilic tannins into hydrophobic PHBV, which is remarkably challenging by using other solvents. Thanks to their well-known properties, the effect of tannins on the antioxidant, UV protection, and gas barrier properties of PHBV was evaluated. Samples containing 5 phr bioadditive revealed the best combination of these properties, also maintaining good transparency. Differential scanning calorimetry (DSC) investigations revealed that films are suitable for application from the fridge to potentially high temperatures for food heating (up to 200 °C). Tensile tests have also shown that Young's modulus (900-1030 MPa) and tensile strength (20 MPa) are comparable with those of the common polymers and biopolymers for packaging. Besides the improvement of the PHBV properties for extending food's shelf-life, it was also observed that PHBV/tannin could colorimetrically detect ammonia vapors, thus making this material potentially applicable as a smart indicator for food spoilage (e.g., detection of fish degradation). The presented outcomes suggest that tannins can add multifunctional properties to a polymeric material, opening up a new strategy to obtain an attractive alternative to petroleum-based plastics for smart food packaging applications.
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Poli-Hidroxialcanoatos , Animais , Taninos , Embalagem de Alimentos , Biopolímeros/química , PlásticosRESUMO
In the last two decades, the use of phthalates has been restricted worldwide due to their well-known toxicity. Nonetheless, phthalates are still widely used for their versatility, high plasticization effect, low cost, and lack of valuable alternatives. This study presents the fully bio-based and versatile glycerol trilevulinate plasticizer (GT) that was obtained by the valorization of glycerol and levulinic acid. The mild-conditions and solvent-free esterification used to synthesize GT was optimized by investigating the product by Fourier transform infrared and NMR spectroscopy. An increasing content of GT, from 10 to 40 parts by weight per hundred parts of resin (phr), was tested with poly(vinyl chloride), poly(3-hydroxybutyrate), poly(3-hydroxybutyrate-co-3-hydroxyvalerate), poly(lactic acid), and poly(caprolactone), which typically present complicated processability and/or mechanical properties. GT produced a significant plasticization effect on both amorphous and semicrystalline polymers, reducing their glass-transition temperature and stiffness, as observed by differential scanning calorimetry measurements and tensile tests. Remarkably, GT also decreased both the melting temperature and crystallinity degree of semicrystalline polymers. Furthermore, GT underwent enzyme-mediated hydrolysis to its initial constituents, envisioning a promising prospective for environmental safety and upcycling. Furthermore, 50% inhibitory concentration (IC50) tests, using mouse embryo fibroblasts, proved that GT is an unharmful alternative plasticizer, which makes it potentially applicable in the biomedical field.
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This work is focused on the application of Life Cycle Assessment (LCA) methodology for the quantification of the potential environmental impacts associated with the obtainment of levulinic acid from residual Cynara cardunculus L. biomass and its subsequent valorization in innovative bioplasticizers for tuning the properties as well as the processability of biopolymers. This potentially allows the production of fully biobased and biodegradable bioplastic formulations, thus addressing the issues related to the fossil origin and nonbiodegradability of conventional additives, such as phthalates. Steam explosion pretreatment was applied to the epigean residue of C. cardunculus L. followed by a microwave-assisted acid-catalyzed hydrolysis. After purification, the as-obtained levulinic acid was used to synthesize different ketal-diester derivatives through a three-step selective synthesis. The levulinic acid-base additives demonstrated remarkable plasticizing efficiency when added to biobased plastics. The LCA results were used in conjunction with those from the experimental activities to find the optimal compromise between environmental impacts and mechanical and thermal properties, induced by the bioadditives in poly(3-hydroxybutyrate), PHB biopolymer.
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A significant mechanical properties mismatch between natural bone and the material forming the orthopedic implant device can lead to its failure due to the inhomogeneous loads distribution, resulting in less dense and more fragile bone tissue (known as the stress shielding effect). The addition of nanofibrillated cellulose (NFC) to biocompatible and bioresorbable poly(3-hydroxybutyrate) (PHB) is proposed in order to tailor the PHB mechanical properties to different bone types. Specifically, the proposed approach offers an effective strategy to develop a supporting material, suitable for bone tissue regeneration, where stiffness, mechanical strength, hardness, and impact resistance can be tuned. The desired homogeneous blend formation and fine-tuning of PHB mechanical properties have been achieved thanks to the specific design and synthesis of a PHB/PEG diblock copolymer that is able to compatibilize the two compounds. Moreover, the typical high hydrophobicity of PHB is significantly reduced when NFC is added in presence of the developed diblock copolymer, thus creating a potential cue for supporting bone tissue growth. Hence, the presented outcomes contribute to the medical community development by translating the research results into clinical practice for designing bio-based materials for prosthetic devices.
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Most of the copper sulfide synthetic approaches developed until now are still facing issues in their procedure, such as long synthesis duration, high energetic consumption, and high implementation costs. This publication reports a facile and sustainable approach for synthesizing copper sulfides on a large scale. In particular, an industrial by-product of sulfur waste was used as a sulfurizing agent for copper sulfide synthesis in a water medium. The reaction was performed in the hydrothermal environment by following a novel proposed mechanism of copper sulfide formation. The investigation of morphological and optical properties revealed that the target products obtained by using waste possess the resembling properties as the ones synthesized from the most conventional sulfurizing agent. Since the determined band gap of synthesis products varied from 1.72 to 1.81 eV, the photocatalytic properties, triggered under visible light irradiation, were also investigated by degrading the methylene blue as a model pollutant. Importantly, the degradation efficiency of the copper sulfide synthesized from sulfur waste was equivalent to a sample obtained from a reference sulfurizing agent since the value for both samples was 96% in 180 min. This very simple synthetic approach opens up a new way for large-scale sustainable production of visible-light-driven photocatalysts for water purification from organic pollutants.