Influence of polymeric flame retardants based on phosphorus‐containing polyesters on morphology and material characteristics of poly(butylene terephthalate)

Flame retarded poly(butylene terephthalate) (PBT) is required for electronic applications and is mostly achieved by low molar mass additives so far. Three phosphorus‐containing polyesters are suggested as halogen‐free and polymeric flame retardants for PBT. Flame retardancy was achieved according to cone calorimeter experiments showing that the peak heat release rate and total heat evolved were reduced because of flame inhibition and condensed‐phase activity. The presented polymers containing derivatives of 9,10‐dihydro‐9‐oxa‐10‐phosphaphenanthrene‐10‐oxide form immiscible blend systems with PBT. Shear‐rheology shows an increase in storage moduli at low frequencies. This is proposed as quantitative measure for the degree of phase interaction. The phase structure of the blends depends on the chemical structure of the phosphorus polyester and was quite different, depending also on the viscosity ratio between matrix and second phase. A lower viscosity ratio leads to two types of phases with spherical and additionally continuous droplets. Addition of the flame retardants showed no influence on the dielectric properties but on the mechanical behavior. The polymeric flame retardants significantly diminish the impact strength because of several reasons: (1) high brittleness of the phosphorus polyesters themselves, (2) thermodynamic immiscibility, and (3) weak phase adhesion. By adding a copolymer consisting of the two base polymers to the blend, an improvement of impact strength was obtained. The copolymer particularly acts as compatibilizer between the phases and therefore leads to a smaller phase size and to a stronger phase adhesion due to the formation of fibrils. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Pluralism at the edge of the millenium: Psychoanlysis traverses the continent and the ocean: A round table discussion with prominent analysts: Perspectives on therapeutic action.

The spring 1999 meeting of Division 39, prior to our entry into a new century, brought together prominent and diverse voices within psychoanalysis at a round table discussion. Rather than report on the questions posed for the panelists and their responses, the author presents a brief case vignette offered during the panel discussion. The various panelists' clinical and theoretical positions from their wide-ranging responses to the questions presented are extracted. The author applies their positions to this case and also offers some of the answers that directly related to the clinical presentation. It is believed that this format highlights the similarities and differences that did not emerge as sharply when the panelists offered their commentary to the more generalized queries. The panelists' views on idealization, an issue that further reflected their disparate stances, are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

High refractive index hyperbranched polymers with different naphthalene contents prepared through thiol-yne click reaction using di-substituted asymmetric bulky alkynes

In the present study, different aromatic moieties, naphthalene and benzene, were introduced into alkynes to constitute 1,3,5-tris(naphthylethynyl)benzene as B₃ monomer. This monomer could be reacted with different ratios of hexane-1,6-dithiol (A₂ monomer) via mono-selective Thiol-Yne reaction (TYR) to form hyperbranched polymers PI. TYR yielded in both, model reactions and polymerizations, mono-adducts with high regioselectivity and proved the absence of any bis-adducts. Polymers of very high molecular weights of up to 625,000 g/mol could be achieved without any sign of gel formation. All the polymers exhibit high transparency in the visible wavelength range and also show high refractive indices of up to 1.745 at 589.7 nm due to the high incorporation of naphthalene and phenyl groups. Besides, all polymers prove excellent solubility and processability together with excellent thermal properties.     

Biological activities of malvidin, a red wine anthocyanidin

Malvidin (mv) has been identified as a potential inhibitor of 3',5'-cyclic adenosine monophosphate (cAMP) phosphodiesterases (PDE). This study was to investigate if, as a possible consequence of intracellular PDE inhibition, the activity of the mitogen-activated protein kinase (MAPK) cascade is affected by mv treatment. At a concentration of 5 microM of mv a significant decrease of phosphorylated ERK1 and ERK2 (ERK, extracellular regulated kinase) in HT29 cells was observed. However, an increase in substance concentration led to a substantial recurrence of the phosphorylated enzymes. Cell cycle analysis underlined that indeed G(1)-relevant targets are only marginally affected by mv. The recurrence of phosphorylated ERK1/2 and the lack of effectiveness on the G(1)-passage up to 100 microM indicated that the inhibition of cAMP-specific PDEs is of minor relevance for the growth-inhibitory properties of mv in HT29 cells. In contrast, the release of cells, synchronised in the G(2)/M-phase of the cell cycle by nocodazole treatment, was effectively blocked in the presence of 1 microM mv. These results suggest that mv interferes with cellular targets relevant for G(2)/M-progression which have not been identified so far.     

Deformation bands, the LEDS theory, and their importance in texture development: Part II. Theoretical conclusions

The facts regarding “regular” deformation bands (DBs) outlined in Part I of this series of articles are related to the low-energy dislocation structure (LEDS) theory of dislocation-based plasticity. They prompt an expansion of the theory by including the stresses due to strain gradients on account of changing selections of slip systems to the previously known dislocation driving forces. This last and until now neglected driving force is much smaller than the components considered hitherto, principally due to the applied stress and to mutual stress-screening among neighbor dislocations. As a result, it permits a near-proof of the LEDS hypothesis, to wit that among all structures which, in principle, are accessible to the dislocations, that one is realized which has the lowest free energy. Specifically, the temperature rises that would result from annihilating the largest DBs amount to only several millidegrees Centigrade, meaning that they, and by implication the entire dislocation structures, are close to thermodynamical equilibrium. This is in stark contrast to the assumption of the presently widespread self-organizing dislocation structures (SODS) modeling that plastic deformation occurs far from equilibrium and is subject to Prigogine’s thermodynamics of energy-flow-through systems. It also holds out promise for future rapid advances in the construction of constitutive equations, since the LEDS hypothesis is the principal basis of the LEDS theory of plastic deformation and follows directly from the second law of thermodynamics in conjunction with Newton’s third law. By contrast, all other known models of metal plasticity are in conflict with the LEDS hypothesis. In regard to texture modeling, the present analysis shows that Taylor’s criterion of minimum plastic work is incorrect and should be replaced by the criterion of minimum free energy in the stressed state. Last, the LEDS hypothesis is but a special case of the more general low-energy structure (LES) hypothesis, applying to plastic deformation independent of the deformation mechanism. It is thus seen that plastic deformation is one of nature’s means to generate order, as a byproduct of the entropy generation when mechanical work is largely converted into heat.     

Lifestyle Meets Market: Bohemian Entrepreneurs in Creative Industries

By linking lifestyle studies with creative industries research, this article opens a new perspective on creativity and innovation management. We argue that artists in the creative industries have to bridge the gap between artistic work and the economic need for self‐management, and that a bohemian lifestyle essentially supports them in doing so. The bohemian lifestyle, which is characterized by a devotion to art for art’s sake, is an essential source for work motivation of artists and an increasing number of other creative workers. The article draws upon an empirical study into artistic work and employment in German theatres. Enacting a bohemian lifestyle enables actors as ‘bohemian entrepreneurs’ to integrate intensive self‐management and self‐marketing as well as subordination of private life to work into their artistic work life. Analysing the link between lifestyle and creative work is crucial for understanding the way in which creative workers become artists and, at the same time, entrepreneurs of their creative talent.