Diblock copolymers with polymethyl methacrylate and side chain liquid crystalline (LC) azopolymethacrylate blocks were synthesized by atom transfer radical polymerization (ATRP). The azobenzene content in these copolymers ranges from 52 to 7 wt %. For an azo content down to 20% they exhibit a LC behavior similar to that of the azo homopolymers. Thin films of these copolymers were characterized by transmission electron microscopy (TEM). A lamellar nanostructure was observed for azo content down to 20 wt %, while no structure is observed for the copolymer with a 7% azo content. The optical anisotropy induced in these films by illumination with linearly polarized 488 nm light was studied and the results compared with those of the azo homopolymer and of a random copolymer with a similar composition. The formation of azo aggregates inside the azo blocks is strongly reduced in going from the homopolymer to the copolymers. Photoinduced azo orientation perpendicular to the 488 nm light polarization was found in all the polymers. The orientational order parameter is very similar in the homopolymer and in the block copolymers with an azo content down to 20 wt %, while it is much lower in the random copolymer and in the 7 wt %. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 1899–1910, 2007

There is extensive evidence of gender inequality in research leading to insufficient representation of women in leadership positions. Numbers revealing a gender gap in research are periodically reported by national and international institutions but data on perceptions of gender equality within the research community are scarce. In the present study, a questionnaire based on the British Athena Survey of Science, Engineering and Technology (ASSET 2016) was distributed among researchers working in Spain. Consistent with the original UKbased study, women in research perceived a greater degree of gender inequality than men. This difference was consistent from junior to senior positions, within public and private universities as well as research centres, and across all research disciplines. When responses were compared with the existing UK-based questionnaire, researchers in Spain felt that women and men are treated more equally in the workplace, yet they perceived their home departments to be less supportive regarding matters of gender equality. The results of this study provide clear evidence that men and women do not share the same perceptions of gender equality in science and that their differing perceptions are relatively consistent across two major European countries. The fact that men occupy the majority of senior positions while not perceiving the same inequality as women do, may be critical when it comes to ensuring the fair ascent of women to senior positions in an academic system. These data encourage the implementation of measures to ensure that both men and women are aware of gender biases in research.PLOS ONE | https://doi.org/10.1371/journal.pone.research and innovation in Europe [2], showed that only 21% of grade A, top-level researchers were women and, strikingly, numbers have not improved much from the 20% observed in 2010. In the Spanish academic system, the representation of women is nearly identical to that of the rest of the EU (40.8% vs 41.0%), and women occupy 21.0% of senior positions in Spain vs 20.9% in the EU [2,3].Gender perceptions may influence women's ascent to senior positions [4]. Women are perceived as worse scientific leaders [5,6] and are stereotyped as not possessing the innate talent that is required in some fields [7]. These and other gender stereotypes may explain why women receive similar levels of research funding when they are judged on the quality of their research but less funding when judged on the excellence of the researcher [8], are less frequently invited to conferences [9,10], are less likely to be selected for scientific awards [11,12], are less represented on editorial boards [13], their work is less likely to be cited [14], they have less chances of being invited to participate in peer review [14,15], and they have a more restricted access to influential networks [16]. In 2015, Handley et al reported that men do not recognise the presence of gender bias in research to the same extent as women: when men and women were asked to read an abstract from a study reportin...

The synthesis and photopolymerization of various liquid crystalline dioxetanes is described. The effects of the spacer length, structure of the mesogenic group and oxetane group on the liquid crystalline properties, polymerization behaviour and optical properties (birefringence) of the oriented and crosslinked network formed in photo-polymerization are discussed. Thermally stable films with birefringence values up to 0.13 can be formed from these materials. The dioxetanes show significantly lower polymerization shrinkage than do structurally related diacrylates.

No abstract