Shape memory behavior of crystalline shape memory polyurethane (SPU) reinforced with graphene, which utilizes melting temperature as a shape recovery temperature, was examined with various external actuating stimuli such as direct heating, resistive heating, and infrared (IR) heating. Compatibility of graphene with crystalline SPU was adjusted by altering the structure of the hard segment of the SPU, by changing the structure of the graphene, and by changing the preparation method of the graphene/SPU composite. The SPU made of aromatic 4,4'-diphenylmethane diisocyanate (MSPU) exhibited better compatibility with graphene, having an aromatic structure, compared to that made of the aliphatic hexamethylene diisocyanate. The finely dispersed graphene effectively reinforced MSPU, improved shape recovery of MSPU, and served effectively as a filler, triggering shape recovery by resistive or IR heating. Compatibility was enhanced when the graphene was modified with methanol. This improved shape recovery by direct heating, but worsened the conductivity of the composite, and consequently the efficiency of resistive heating for shape recovery also declined. Graphene modified with methanol was more effective than pristine graphene in terms of shape recovery by IR heating.
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http://dx.doi.org/10.3390/ma7031520 | DOI Listing |
Biomech Model Mechanobiol
January 2025
CNR Istituto Officina Dei Materiali, Area Science Park Basovizza, S.S. 14, Km 163,5, 34149, Trieste, Italy.
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View Article and Find Full Text PDFInflammopharmacology
January 2025
Riphah Institute of Pharmaceutical Sciences, Riphah International University, Islamabad, 45210, Pakistan.
Flurbiprofen (FBP) is poorly water-soluble BCS class II drug with anti-inflammatory and analgesic effects, used to treat arthritis and degenerative joint diseases. This study was aimed to develop SNEDDS loaded with FBP. Six SNEDDS using two oils olive oil (F, F, F) and castor oil (F, F, F) with three different Smix ratios consisting of Tween 20 and PEG 400 (1:1, 1:2, 2:1) were prepared and characterized.
View Article and Find Full Text PDFAfter years of armed conflict in northern Uganda, many local people have turned to Evangelical churches for help with healing and recovery. We observe that the healing practices in these churches encourage particular notions of what the mind is, how the mind works and whether it is bounded or porous to the outside world. In the traditional cultural setting in which these people grew to adulthood, many accept that vengeance can attack supernaturally from without.
View Article and Find Full Text PDFIssues Ment Health Nurs
January 2025
Department of Regional Health Research, University of Southern Denmark, Odense, Denmark.
Friendships are vital for the well-being of young adults, yet their social network is often reduced during episodes of life-disruptive mental distress, such as psychosis. Despite this, our study shows that young adults do either maintain or build friendships during such periods and that these relationships are crucial for recovery in youth. As research on the role of friendships in the recovery journey of this group is limited, this study explores the significance of friendships for young adults engaged in early psychosis interventions to generate insights that can inform mental health recovery practices.
View Article and Find Full Text PDFPolymers (Basel)
December 2024
Faculty of Materials Science and Engineering, "Gheorghe Asachi" Technical University of Iași, Blvd. Dimitrie Mangeron 71A, 700050 Iasi, Romania.
The paper starts by describing the manufacturing process of cups thermoformed from extruded foils of 80% recycled PET (80r-PET), which comprises heating, hot deep drawing and cooling. The 80r-PET foils were heated up to 120 °C, at heating rates of the order of hundreds °C/min, and deep drawn with multiple punchers, having a depth-to-width ratio exceeding 1:1. After puncher-assisted deformation, the cups were air blown away from the punchers, thus being "frozen" in the deformed state.
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