Search results for "Materiali"
showing 10 items of 876 documents
Mesophase formation in poly(propylene-ran-1-butene) by rapid cooling
2009
Abstract The effect of random insertion of low amount of 1-butene of less than about 11 mol% into the isotactic polypropylene chain on structure formation at non-isothermal crystallization at different rate of cooling was investigated by X-ray scattering, density measurements, and atomic force and polarizing optical microscopy. Emphasis is put on the evaluation of the condition of crystallization for replacement of lamellar crystals by mesomorphic nodules on increasing the cooling rate/supercooling. In the polypropylene homopolymer, mesophase formation occurs on cooling at rates larger about 150–200 K s −1 , while in case of poly(propylene- ran -1-butene) mesophase formation is observed on …
“Effect of Filler Type and Processing Apparatus on the Properties of the Recycled “Light Fraction” from Municipal Post-Consumer Plastics”
2001
Plastic waste or scraps are generated from two main sources: industrial wastes and post-consumer wastes. By using the flotation method, generally two fractions are obtained from municipal post-consumer wastes: a light fraction, floating on water, and a heavy fraction. The former is essentially made of low and high density polyethylene—LDPE, HDPE—and polypropylene—PP; the heavy fraction is formed by poly(vinyl chloride)—PVC—and poly(ethylene terephthalate)—PET. In this work, the recycling of a light fraction from municipal post-consumer plastics has been studied, considering also the effect of filler type—glass fibres, calcium carbonate and wood fibres—and processing apparatus—discountinous …
Use of PP-g-OXA in the Compatibilization of PP/LCP Blends
1999
Abstract Adding small amounts of liquid crystalline polymers (LCP) to flexible thermoplastic matrices (FTP) allows to enhance the mechanical and thermomechanical properties. Therefore it is possible to obtain materials with new properties only by simple mixing. A strong shortcoming is the incompatibility between LCP and FTP that leads to materials with very poor properties unusable for commercial pourposes. The presence of a compatibilizer is therefore required. Oxazoline functionality is known to be highly reactive toward many other functional groups and then oxazoline functionalized polymers can be efficiently used as compatibilizer precursors. In this work the compatibilizazion of polypr…
Multifunctional polyurethane foams with thermal energy storage/release capability
2020
In this work, polyurethane (PU) insulating panels containing different amounts of a microencapsulated paraffin with a nominal melting temperature of 24 °C, used as phase change material (PCM), were produced. The resulting panels behaved as multifunctional materials able to thermally insulate and simultaneously storing/releasing thermal energy near room temperature. The panels were characterized from a microstructural, thermal and mechanical point of view. Viscosity measurements highlighted an increase in the viscosity values of the PU liquid precursors due to the addition of the capsules, and this could lead to some difficulties during the production stages, especially in the mixing and foa…
Characterization of PLLA scaffolds for biomedical applications
2017
The porosity and pore size distribution of three-dimensional scaffolds have direct implications on their biomedical applications (tissue engineering, drug delivery, and wound dressing). Accordingly, in this paper, a fast, facile, and conservative method relying on low-field nuclear magnetic resonance (LF-NMR) for the evaluation of mean pore size and pore size distribution of polymeric scaffolds is reported. The applicability of the technique is demonstrated on poly-L-lactic acid scaffolds fabricated using the thermal induced phase separation. Results obtained through LF-NMR are successfully compared to scanning electron microscope and X-ray microcomputed tomography micrographs.
More Than Meets the Eye: Toward a Post-Materialist Model of Consciousness.
2015
Commonly accepted models of human consciousness have substantial shortcomings, in the sense that they cannot account for the entire scope of human experiences. The goal of this article is to describe a model with higher explanatory power, by integrating ideas from psychology and quantum mechanics. In the first part, the need for a paradigm change will be justified by presenting three types of phenomena that challenge the materialistic view of consciousness. The second part is about proposing an alternative view of reality and mind–matter manifestation that is able to accommodate these phenomena. Finally, the ideas from the previous parts will be combined with the psychological concepts deve…
Sports participation and cultural trends. Running as a reflection of individualisation and post-materialism processes in Spanish society
2014
AbstractThis article examines the relationship between cultural change processes and the practice of running. The empirical basis is the national survey on Spanish sport habits carried out in 2005. Specifically, the subsamples of runners (n = 343) and other sport modalities (n = 2,687) were used. The study reveals that runners are characterised by more post-materialist and individualist tendencies than the rest of the participants. The results suggest the existence of a close relationship between the predominant cultural orientations and certain types of sport activity.
The Lineup of Social Entrepreneurship
2021
As an introductory chapter to the second section, this chapter describes the sequence of the social entrepreneurship analysis followed from the macro perspective. As a chronology, the construction of social ventures begins with a social problem or an unjust social equilibrium. At this point, an individual tries to change the unjust situation through a disruptive idea. The big challenge for that individual arises because, as in any equilibrium situation, institutional forces make difficult the shift from one situation to another. One of the main issues linked to the institutional forces is legitimacy, which can be seen to a certain extent as conflicts of interest. Finally, social ventures an…
L’ecologisme dels pobles. “Poca gent et dirà que és ecologista, però fem com si ho fórem perquè ho hem viscut de sempre”
2019
Aquest article desafia el sentit comú que ens informa que el desenvolupament socioeconòmic, al llarg de la història, ha comportat una millor consciència medi ambiental, una visió comunament acceptada que ha rebut suport teòric de la tesi postmaterialista. A partir d’un estudi qualitatiu –portat a terme a pobles que envolten el Delta de l’Ebre i l’Albufera de València— l’anàlisi d’enquestes que tracten temes mediambiental i l’anàlisi de les petjades ecològica i material, demostrarem com aquesta manera postmaterialista d’entendre el medi ambient, aliena la conscienciació mediambiental de les pràctiques i estils de vida. I el que és encara més importat, aliena la consciència mediambiental del …
What is new in new materialism for a newcomer?
2018
AbstractHaving recently emerged as an intellectual project, new materialism (NM) is extending to different fields, including sport, exercise and health studies. However, it is still unclear why and how NM is new, which can jeopardise its potential impact in academia and society. The aim of this paper is to discuss the newness of NM and to explore how it plays out in relation to different issues, such as knowledge translation and partisan positions. At the same time, NM is used as a way of understanding my own positionality as a newcomer who is becoming an academic within a field having manifold intellectual debates while being shaped by a neoliberal rationality. Reasons as to why NM has to …